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  • 1.
    AbdelMageed, Manar
    et al.
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology. Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry. Department of Pathology, Faculty of Veterinary Medicine, Zagazig University, Zagazig 44511, Egypt.
    Ali, Haytham
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology. Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry. Department of Pathology, Faculty of Veterinary Medicine, Zagazig University, Zagazig 44511, Egypt.
    Ohlsson, Lina
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Lindmark, Gudrun
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Sitohy, Basel
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology. Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    The Chemokine CXCL16 Is a New Biomarker for Lymph Node Analysis of Colon Cancer Outcome2019In: International Journal of Molecular Sciences, ISSN 1661-6596, E-ISSN 1422-0067, Vol. 20, no 22, article id 5793Article in journal (Refereed)
    Abstract [en]

    hemokines are important in the development and progression of tumors. We investigated the expression of CXCL14 and CXCL16 in colon cancer. Expression of mRNA was assessed in primary tumors and lymph nodes and CXCL16 mRNA levels were correlated to patient’s survival. Protein expression was investigated by two-color immunofluorescence and immunomorphometry. CXCL14 and CXCL16 mRNA levels and protein expression were significantly higher in colon cancer primary tumors compared to apparently normal colon tissue. Positive cells were tumor cells, as revealed by anti-CEA and anti-EpCAM staining. CXCL16, but not CXCL14, mRNA levels were significantly higher in hematoxylin and eosin positive (H&E(+)) compared to H&E(−) colon cancer lymph nodes or control nodes (P < 0.0001). CXCL16 mRNA was expressed in 5/5 colon cancer cell lines while CXCL14 was expressed significantly in only one. Kaplan-Meier analysis revealed that colon cancer patients with lymph nodes expressing high or very high levels (7.2 and 11.4 copies/18S rRNA unit, respectively) of CXCL16 mRNA had a decreased mean survival time of 30 and 46 months at the 12-year follow-up (P = 0.04, P = 0.005, respectively). In conclusion, high expression of CXCL16 mRNA in regional lymph nodes of colon cancer patients is a sign of a poor prognosis.

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  • 2.
    AbdelMageed, Manar
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology. Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology. Department of Pathology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt.
    Ismail, Hager
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology. Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology. Department of Clinical Pathology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt.
    Ohlsson, Lina
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Lindmark, Gudrun
    Institution of Clinical Sciences, Lund University, Helsingborg, Sweden.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Sitohy, Basel
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology. Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Clinical significance of stem cell biomarkers epcam, lgr5 and lgr4 mrna levels in lymph nodes of colon cancer patients2022In: International Journal of Molecular Sciences, ISSN 1661-6596, E-ISSN 1422-0067, Vol. 23, no 1, article id 403Article in journal (Refereed)
    Abstract [en]

    The significance of cancer stem cells (CSCs) in initiation and progression of colon cancer (CC) has been established. In this study, we investigated the utility of measuring mRNA expression levels of CSC markers EpCAM, LGR5 and LGR4 for predicting survival outcome in surgically treated CC patients. Expression levels were determined in 5 CC cell lines, 66 primary CC tumors and 382 regional lymph nodes of 121 CC patients. Prognostic relevance was determined using Kaplan‐Meier survival and Cox regression analyses. CC patients with lymph nodes expressing high levels of EpCAM, LGR5 or LGR4 (higher than a clinical cutoff of 0.07, 0.06 and 2.558 mRNA cop-ies/18S rRNA unit, respectively) had a decreased mean survival time of 32 months for EpCAM and 42 months for both LGR5 and LGR4 at a 12‐year follow‐up (p = 0.022, p = 0.005 and p = 0.011, respec-tively). Additional patients at risk for recurrence were detected when LGR5 was combined with the biomarkers CXCL17 or CEA plus CXCL16. In conclusion, the study underscores LGR5 as a particularly useful prognostic biomarker and illustrates the strength of combining biomarkers detecting different subpopulations of cancer cells and/or cells in the tumor microenvironment for predicting recurrence.

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  • 3.
    Ali, Haytham
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology. Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology. Department of Animal and Veterinary Sciences, College of Agricultural and Marine Sciences, Sultan Qaboos University, Muscat, Oman.
    AbdelMageed, Manar
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology. Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology. Department of Pathology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt.
    Ohlsson, Lina
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Lindmark, Gudrun
    Institution of Clinical Sciences, Lund University, Lund, Sweden.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Sitohy, Basel
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology. Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology.
    Detection of lymph node metastasis in colon cancer by ectopically expressed fibroblast markers FOXQ1 and THBS22023In: Frontiers in Oncology, E-ISSN 2234-943X, Vol. 13, article id 1297324Article in journal (Refereed)
    Abstract [en]

    Introduction: Approximately 25% of colon cancer (CC) patients having curative surgery will relapse. Therefore, it is crucial to identify patients with increased recurrence risk to offer them adjuvant chemotherapy. Three markers with prominent expression in fibroblasts: forkhead box Q1 (FOXQ1), matrix metalloproteinase-11 (MMP11), and thrombospondin-2 (THBS2), and the fibroblast expressed chemokine CXCL12 were selected for studies because of the critical role of fibroblasts in the microenvironment of the tumor.

    Methods: The expression levels of the biomarkers were assessed in primary CC tumors, lymph nodes of CC patients and controls, and CC cell lines at mRNA and protein levels by real-time qRT-PCR and immunohistochemistry, respectively.

    Results: FOXQ1, MMP11, and THBS2 mRNAs were expressed at significantly higher levels in primary tumors compared to normal colon (P=0.002, P<0.0001, and P<0.0001, respectively). In contrast, CXCL12 mRNA levels were higher in normal colon tissue. FOXQ1, MMP11, and THBS2 levels were also expressed at significantly higher levels in metastasis-positive lymph nodes compared to both metastasis-negative- and control nodes (P<0.0001/P=0.002, P<0.0001/P<0.0001, and P<0.0001/P<0.0001, respectively). Immuno-morphometry revealed that 30–40% of the tumor cells expressed FOXQ1, MMP11, and THBS2. FOXQ1 and THBS2 were barely detected in normal colon epithelium (P<0.0001), while MMP11 was expressed in normal colon epithelium at high levels.

    Discussion: We conclude that CC tumor cells show ectopic expression of FOXQ1 and THBS2 possibly making these tumor cells independent of fibroblast cell support. The high expression levels of these two biomarkers in metastatic lymph nodes suggest that they are potential indicators of patients at risk for recurrence.

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  • 4.
    Ali, Haytham
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology. Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology. Department of Pathology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt.
    AbdelMageed, Manar
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology. Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology. Department of Pathology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt.
    Olsson, Lina
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Israelsson, Anne
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Lindmark, Gudrun
    Department of Clinical Sciences, Lund University, Helsingborg, Sweden.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Sitohy, Basel
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology.
    Utility of G protein-coupled receptor 35 expression for predicting outcome in colon cancer2019In: Tumor Biology, ISSN 1010-4283, E-ISSN 1423-0380, Vol. 41, no 6, article id 1010428319858885Article in journal (Refereed)
    Abstract [en]

    The utility of mRNA and protein determinations of G protein-coupled receptor 35, that is, GPR35a (GPR35 V1) and GPR35b (GPR35 V2/3), as indicators of outcome for colon cancer patients after curative surgery was investigated. Expression levels of V1 and V2/3 GPR35, carcinoembryonic antigen and CXCL17 mRNAs were assessed in primary tumours and regional lymph nodes of 121 colon cancer patients (stage I–IV), colon cancer cell lines and control colon epithelial cells using real-time quantitative reverse transcriptase-polymerase chain reaction. Expression of G protein-coupled receptor 35 was investigated by two-colour immunohistochemistry and immunomorphometry. GPR35 V2/3 mRNA, but not V1 mRNA, was expressed in colon cancer cell lines, primary colon tumours and control colon epithelial cells. Haematoxylin and eosin positive (H&E(+)), but not H&E(–), lymph nodes expressed high levels of GPR35 V2/3 mRNA (P<0.0001). GPR35b and carcinoembryonic antigen proteins were simultaneously expressed in many colon cancer tumour cells. Kaplan–Meier and hazard ratio analysis revealed that patients with lymph nodes expressing high levels of GPR35 V2/3 mRNA and, in particular, in the group of patients with lymph nodes also expressing carcinoembryonic antigen mRNA, had a short disease-free survival time, 67 months versus 122 months at 12-year follow-up (difference: 55 months, P = 0.001; hazard ratio: 3.6, P = 0.002). In conclusion, high level expression of G protein-coupled receptor 35 V2/3 mRNA in regional lymph nodes of colon cancer patients is a sign of poor prognosis.

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  • 5.
    Ali, Haytham
    et al.
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology. Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry. Department of Pathology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt.
    Ohlsson, Lina
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Lindmark, Gudrun
    Institution of Clinical Sciences, Lund University, SE, Lund, Sweden.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Sitohy, Basel
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology. Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    The myeloid cell biomarker EMR1 is ectopically expressed in colon cancer2021In: Tumor Biology, ISSN 1010-4283, E-ISSN 1423-0380, Vol. 43, no 1, p. 209-223Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: The microenvironment of colon cancer (CC) is heterogeneous including cells of myeloid lineage affecting tumor growth and metastasis. Two functional subtypes of myeloid cells have been identified; one (M1) is tumor-inhibitory and the other one (M2) is tumor-promoting. Whether the three myeloid markers EMR1, CD206 and CD86 are expressed only in the infiltrating myeloid cells or also in the tumor cells was investigated.

    METHODS: Expression of the myeloid markers was investigated in CC at the mRNA and protein levels in primary tumors and lymph nodes. mRNA expression was also determined in 5 CC cell lines. Protein expression was investigated by two-color immunofluorescence and consecutive-sections-immune-staining combined with morphometry using specific antibodies for the myeloid cell markers and the epithelial cell markers CEACAM5 and EpCAM.

    RESULTS: EMR1 and CD86, but not CD206, mRNA levels were significantly higher in CC primary tumors compared to apparently normal colon tissue (P <  0.0001). EMR1 mRNA levels were significantly higher in both hematoxylin-eosin positive (H&E(+)) and H&E(-) lymph nodes of CC patients compared to control nodes (P = 0.03 and P = 0.01, respectively). EMR1 and CD206 mRNAs were expressed in 4/5 and 5/5 CC cell lines, respectively, while CD86 mRNA was not expressed. Immuno-morphometry revealed that about 20% of the tumor cells expressed EMR1 and CD206. Positive cells were tumor cells as revealed by anti-CEACAM5 and anti-EpCAM staining. The number of EMR1, CD206 and CD86 positive cells were significantly increased in CC primary tumors compared to normal colon tissue (P <  0.0001). However, CD206 was also expressed in normal colonocytes. Only EMR1 showed significantly increased numbers of positive tumor cells in H&E(+) nodes compared to H&E(-) nodes (P = 0.001). EMR1 expression in CC tumor cells correlated with CXCL17 expressing tumor cells.

    CONCLUSION: EMR1, like the chemokine CXCL17, is ectopically expressed in colon cancer possibly in the same cancer cells.

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  • 6.
    Baranov, Vladimir
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Carcinoembryonic antigen (CEA) and CEA-related cell adhesion molecule 1 (CEACAM1), apically expressed on human colonic M cells, are potential receptors for microbial adhesion.2004In: Histochemistry and Cell Biology, ISSN 0948-6143, E-ISSN 1432-119X, Vol. 121, no 2, p. 83-9Article in journal (Refereed)
    Abstract [en]

    In the human gut mucosa, specialized M cells deliver intact foreign macromolecules and commensal bacteria from the lumen to organized mucosal lymphoid tissues triggering immune responses. M cells are also major sites of adhesion and invasion for enteric pathogens. The molecular features of M cell apical surfaces that promote microbial normal attachment are still largely unknown. We have demonstrated previously that in the human colonic epithelium, carcinoembryonic antigen (CEA) and CEA-related cell adhesion molecule 1 (CEACAM1) are integral components of the apical glycocalyx which participate in epithelial-microbial interactions. In this study, based on the reactivity of specific monoclonal antibodies and on immunoelectron microscopy, we show that M cells of human colonic solitary lymphoid follicles express CEA and CEACAM1 on the apical surface. Recently these highly glycosylated molecules have been characterized as protein receptors for different bacteria. This leads us to propose a role for CEA and CEACAM1 in the adherence of enteric bacteria to the apical membrane of colonic M cells. We also hypothesize that, unlike colonic enterocytes, M cells lack the defense mechanism that eliminates CEA and CEACAM1 upon microbial binding and which is based on vesiculation of microvillus plasma membrane.

  • 7.
    Baranov, Vladimir
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology. Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Nagaeva, Olga
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Mincheva-Nilsson, Lucia
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Lipids are a constitutive component of cytolytic granules.2000In: Histochemistry and Cell Biology, ISSN 0948-6143, E-ISSN 1432-119X, Vol. 114, no 2, p. 167-71Article in journal (Refereed)
    Abstract [en]

    Cytolytic granules are specific organelles of activated cytotoxic lymphocytes mediating storage and regulated excretion of lytic molecules for killing of target cells. A variety of the other granule components may also participate in granule-mediated cytotoxicity. In this study, the subcellular localization of lipids in the granules of human decidual CD56+ natural killer-like cells was determined by staining with malachite green aldehyde and imidazole-buffered osmium tetroxide. Lipids were shown, for the first time, to be a constitutive component of cytolytic granules. Lipids formed an additional structural microdomain, located between the granule-limiting membrane and the granule core. Images of the granules on serial sections suggested that intragranular lipids wrap the core. We speculate that granule lipids participate in packing of lytic molecules inside the granules, in autocrine signaling ending granule secretion, and in the killing process.

  • 8. Baranov, Vladimir
    et al.
    Yeung, Moorix Mo-Wai
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Expression of carcinoembryonic antigen and nonspecific cross-reacting 50-kDa antigen in human normal and cancerous colon mucosa: comparative ultrastructural study with monoclonal antibodies1994In: Cancer Research, ISSN 0008-5472, E-ISSN 1538-7445, Vol. 54, no 12, p. 3305-3314Article in journal (Refereed)
    Abstract [en]

    The precise localization of carcinoembryonic antigen (CEA) and non-specific cross-reacting 50-kDa antigen (NCA 50) in normal colon mucosa and colon adenocarcinoma was investigated by using an indirect immunoperoxidase electron microscopic technique with specific monoclonal antibodies. In normal adult colon both antigens were localized to microvesicles and filaments of the "fuzzy coat" on the apical surface of the epithelial cells. In addition, NCA 50 was found in the narrow spaces between adjoining microvilli. Mature columnar cells at the free luminal surface contained most of the antigen positive material. CEA and NCA 50 were also detected as intracellular components of goblet cells. In multilayered tumor glands, the cell surface expression of the antigens was dependent on the position of the tumor cell in the gland. The neoplastic cells showed either a predominant apical labeling or a positive staining of almost the entire cell surface. Some of the neoplastic cells contained CEA in so-called "intracellular lumina." In contrast to normal colon epithelial cells most tumor cells synthesized NCA 50 actively. In normal colonic mucosa, unlike in cancerous tissue, CEA and NCA 50 appear to be released via vesicles formed from the microvillous membrane of mature columnar cells. These results are consistent with the hypothesis that CEA and NCA play a role in the nonspecific defense against microorganisms in the large intestine.

  • 9.
    Bas, A
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Forsberg, G
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry. Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Sjöberg, Veronika
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hernell, Olle
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Aberrant extrathymic T cell receptor gene rearrangement in the small intestinal mucosa: a risk factor for coeliac disease?2009In: Gut, ISSN 0017-5749, E-ISSN 1468-3288, Vol. 58, no 2, p. 189-195Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Coeliac disease is a small intestine enteropathy caused by permanent intolerance to wheat gluten. Gluten intake by patients with coeliac disease provokes a strong reaction by intestinal intraepithelial lymphocytes (IELs), which normalises on a gluten-free diet. AIM: To investigate whether impaired extrathymic T cell maturation and/or secondary T cell receptor (TCR) gene recombination in IELs are features of coeliac disease which could contribute to the failure of establishing tolerance to gluten.

    METHODS: Expression levels of the four splice-forms of recombination activating gene-1 (RAG1) mRNA and preT alpha-chain (preTalpha) mRNA were determined in IEL-subsets of children with coeliac disease and controls. Frequencies of RAG1 expressing IELs were determined by immunomorphometry.

    RESULTS: In controls, the RAG1-1A/2 splice-form selectively expressed outside the thymus, was dominant and expressed in both mature (TCR(+)) and immature (CD2(+)CD7(+)TCR(-)) IELs ( approximately 8 mRNA copies/18S rRNA U). PreTalpha was expressed almost exclusively in CD2(+)CD7(+)TCR(-) IELs ( approximately 40 mRNA copies/18S rRNA U). By contrast, RAG1 and preTalpha mRNA levels were low in patients with coeliac disease compared to controls, both with active disease and with inactive, symptom-free disease on a gluten-free diet (p values <0.01 for mature and <0.05 for immature IELs). Similarly, the frequencies of RAG1+ IELs were significantly lower in patients with coeliac disease compared to controls (p<0.001).

    CONCLUSIONS: Patients with coeliac disease appear to have an impaired capacity for extrathymic TCR gene rearrangement. This is an inherent feature, which probably plays a pivotal role in the failure to efficiently downregulate the T cell response to gluten.

  • 10.
    Bas, Anna
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Forsberg, Göte
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology. Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Utility of the housekeeping genes 18S rRNA, β-actin, and glyceraldehyde-3-phosphate-dehydrogenase (GAPDH) for normalisation in real-time quantitative RT-PCR analysis of gene expression in human T lymphocytes2004In: Scandinavian Journal of Immunology, ISSN 0300-9475, E-ISSN 1365-3083, Vol. 59, no 6, p. 566-573Article in journal (Refereed)
    Abstract [en]

    The accuracy of 18S rRNA, β-actin mRNA and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA as indicators of cell number when used for normalization in gene expression analysis of T lymphocytes at different activation stages was investigated. Quantitative real-time reverse transcriptase-polymerase chain reaction was used to determine the expression level of 18S rRNA, β-actin mRNA, GAPDH mRNA and mRNA for six cytokines in carefully counted samples of resting human peripheral blood mononuclear cells (PBMCs), intestinal lymphocytes and PBMCs subjected to polyclonal T-cell activation. The 18S rRNA level in activated and resting PBMCs and intestinal lymphocytes was essentially the same, while the levels of β-actin and GAPDH mRNAs fluctuated markedly upon activation. When isolated γδTCR+, CD4+ and CD8+ subpopulations were studied, 18S rRNA levels remained unchanged after 21 h of activation but increased slightly after 96 h. In contrast, there was a 30–70-fold increase of GAPDH mRNA/cell in these cell populations upon activation. Cytokine analysis revealed that only normalization to 18S rRNA gave a result that satisfactorily reflected their mRNA expression levels per cell. In conclusion, 18S rRNA was the most stable housekeeping gene and hence superior for normalization in comparative analyses of mRNA expression levels in human T lymphocytes.

  • 11. Bas, Anna
    et al.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Extrathymic TCR gene rearrangement in human small intestine: identification of new splice forms of recombination activating gene-1 mRNA with selective tissue expression.2003In: Journal of Immunology, ISSN 0022-1767, E-ISSN 1550-6606, Vol. 171, no 7, p. 3359-71Article in journal (Refereed)
    Abstract [en]

    Two new 5'-untranslated region (5'UTR) exons were identified in the human gene for the lymphocyte-specific endonuclease recombination activating gene-1 (RAG1) required for the somatic recombination yielding functional Ag receptors. These 5'UTR exons were used in three different splice forms by jejunal lymphocytes of the T cell lineage. RAG1 mRNA containing the previously described 5'UTR exon was not expressed in these cells. Conversely, one of the new 5'UTR exons was not expressed in thymus. The new RAG1 mRNA splice forms were all expressed in immature T cells (CD2(+)CD7(+)CD3(-)). This cell population also expressed high levels of mRNA for the pre-T alpha-chain. In situ hybridization demonstrated jejunal cells expressing the new splice forms of RAG1 mRNA, both intraepithelially and in lamina propria. Pre-T alpha-chain mRNA-expressing cells were detected at the same sites. These results strongly suggest ongoing TCR gene rearrangement in human small intestinal mucosa, yielding T cells specially adapted for this environment. This seems to be achieved by two parallel processes, extrathymic T cell development and peripheral Ag-driven TCR editing.

  • 12. Bjerner, J
    et al.
    Lebedin, Y
    Bellanger, L
    Kuroki, M
    Shively, J E
    Varaas, T
    Nustad, K
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Børmer, O P
    Protein epitopes in carcinoembryonic antigen. Report of the ISOBM TD8 workshop.2002In: Tumor Biology, ISSN 1010-4283, E-ISSN 1423-0380, Vol. 23, no 4, p. 249-62Article in journal (Refereed)
    Abstract [en]

    To characterize antigenic sites in carcinoembryonic antigen (CEA) further and to investigate whether there are differences between colon tumor CEA and meconium CEA (NCA-2) that can be detected by anti-CEA monoclonal antibodies (MAb), 19 new anti-CEA MAb were analyzed with respect to specificity, epitope reactivity and affinity. Their reactivities were compared with 10 anti-CEA MAb with known CEA-domain binding specificity that have previously been classified into five nonoverlapping epitope groups, GOLD 1-5. Cross-inhibition assays with antigen-coated microtiter plates and immunoradiometric assays were performed in almost all combinations of MAbs, using conventionally purified CEA (domain structure: N-A1B1-A2B2-A3B3-C) from liver metastasis of colorectal carcinomas, recombinant CEA, meconium CEA (NCA-2), truncated forms of CEA and NCA (CEACAM6) as the antigens. The affinity of the MAbs for CEA was also determined. The new MAbs were generally of high affinity and suitable for immunoassays. Three new MAbs were assigned to GOLD epitope group 5 (N-domain binding), 3 MAbs to group 4 (A1B1 domain), 1 to group 3 (A3B3 domain), 3 to group 2 (A2B2 domain) and 3 to group 1 (also the A3B3 domain). Three MAbs formed a separate group related to group 4, they were classified as GOLD 4' (A1B1 domain binding). The remaining 3 MAbs appear to represent new subspecificities with some relationship to GOLD groups 1, 2 or 4, respectively. Five MAbs, all belonging to epitope group 1 and 3, reacted strongly with tumor CEA but only weakly or not at all with meconium CEA, demonstrating that the two products of the CEA gene differ from each other, probably due to different posttranslational modifications.

  • 13.
    Eltorky, Hagar
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology. Umeå University, Faculty of Medicine, Department of Diagnostics and Intervention. Department of Biochemistry, Faculty of Science, Zagazig University, Zagazig, Egypt.
    AbdelMageed, Manar
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology. Umeå University, Faculty of Medicine, Department of Diagnostics and Intervention. Department of Pathology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt.
    Ismail, Hager
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology. Umeå University, Faculty of Medicine, Department of Diagnostics and Intervention. Department of Clinical Pathology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt.
    Zahran, Faten
    Department of Biochemistry, Faculty of Science, Zagazig University, Zagazig, Egypt.
    Guirgis, Adel
    Department of Molecular Biology, Genetic Engineering, Biotechnology Research Institute, University of Sadat City, Menoufia, Sadat, Egypt.
    Ohlsson, Lina
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Lindmark, Gudrun
    Institution of Clinical Sciences, Lund University, Lund, Sweden.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Sitohy, Basel
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology. Umeå University, Faculty of Medicine, Department of Diagnostics and Intervention.
    LGR6 is a prognostic biomarker for less differentiated tumors in lymph nodes of colon cancer patients2024In: Frontiers in Oncology, E-ISSN 2234-943X, Vol. 14, article id 1393075Article in journal (Refereed)
    Abstract [en]

    Introduction: The aim was to investigate whether the stem cell marker LGR6 has prognostic value in colon cancer, alone or in combination with the prognostic biomarkers CEA and CXCL16.

    Methods: LGR6 mRNA levels were determined in 370 half lymph nodes of 121 colon cancer patients. Ability to predict relapse after curative surgery was estimated by Kaplan-Meier survival model and Cox regression analyses.

    Results: Patients with high LGR6 levels [LGR6(+)] had a decreased mean survival time of 11 months at 5-year follow-up and 47 months at 12-year follow-up, respectively, with hazard ratios of 3.2 and 2.8. LGR6 mRNA analysis added prognostic value to CEA and CXCL16 mRNA analysis. In the poor prognosis groups CEA(+) and CXCL16(+), further division was achieved by LGR6 analysis. LGR6(+) patients had a very poor prognosis. LGR6 also identified a small number of CEA(-), TNM stage I patients who relapsed suggesting stem cell origin of these tumors. LGR6 and LGR5 levels correlated strongly in lymph nodes of stage I and IV patients but not in stage II patients, suggesting that these stem cell markers are differentially regulated.

    Conclusion: This study highlights LGR6 as a useful prognostic biomarker independently and in combination with CEA, CXCL16 or LGR5 identifying different risk groups.

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  • 14.
    Fahlgren, Anna
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Baranov, Vladimir
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Frängsmyr, L
    Zoubir, F
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Interferon-gamma tempers the expression of carcinoembryonic antigen family molecules in human colon cells: a possible role in innate mucosal defence.2003In: Scandinavian Journal of Immunology, ISSN 0300-9475, E-ISSN 1365-3083, Vol. 58, no 6, p. 628-41Article in journal (Refereed)
    Abstract [en]

    Four carcinoembryonic antigen-related cell adhesion molecule (CEACAM)s, i.e. CEA, CEACAM1, CEACAM6 and CEACAM7, are localized to the apical glycocalyx of normal colonic epithelium and have been suggested to play a role in innate immunity. The expression of these molecules in colon carcinoma cells was studied at the mRNA and protein levels after treatment with interferon-gamma (IFN-gamma), interleukin-1beta, live bacteria or lipopolysaccharide. The colon carcinoma cell lines LS174T and HT-29 were studied in detail using real-time quantitative reverse transcriptase-polymerase chain reaction, immunoflow cytometry and immunoelectron microscopy. IFN-gamma, but not the other agents, modified expression of CEA, CEACAM1 and CEACAM6. None of the agents upregulated CEACAM7 expression. Two expression patterns were seen. HT-29 cells, which initially showed low quantities of mRNAs and proteins, displayed marked upregulation of both mRNAs and proteins. LS174T cells transcribed stable high levels of mRNA before and after treatment. Additionally, IFN-gamma induced increased cell surface expression of CEA, CEACAM1 and CECAM6. IFN-gamma has two important effects on the expression levels of the CEA family molecules in colon epithelial cells: direct upregulation of CEACAM1 and promotion of cell differentiation resulting in increased expression of CEA and CEACAM6 and decreased expression of CEACAM7.

  • 15.
    Fahlgren, Anna
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Baranov, Vladimir
    Frängsmyr, Lars
    Zoubir, Fairouz
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Interferon-γ tempers the expression of carcinoembryonic antigen (CEA) family molecules – a role in innate colonic defence.2003In: Scandinavian Journal of Immunology, Vol. 58, no 6, p. 628-641Article in journal (Refereed)
  • 16.
    Fahlgren, Anna
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Danielsson, Åke
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Hammarstrom, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    β-Defensin-3 and -4 in intestinal epithelial cells display increased mRNA expression in ulcerative colitis2004In: Clinical and Experimental Immunology, ISSN 0009-9104, E-ISSN 1365-2249, Vol. 137, no 2, p. 379-385Article in journal (Refereed)
    Abstract [en]

    mRNA expression of two recently described human beta-defensins (hBD-3 and hBD-4) in epithelial cells of normal small and large intestine and the impact of chronic intestinal inflammation on their expression levels was investigated. Intestinal specimens from patients with ulcerative colitis (UC), Crohn's disease (CD) and controls with no history of inflammatory bowel disease were studied. hBD-3 and hBD-4 mRNAs were determined in freshly isolated epithelial cells by real-time quantitative reverse transcription-polymerase chain reaction (QRT-PCR) and by in situ hybridization. The effect of proinflammatory cytokines on hBD-3 and hBD-4 mRNA expression in colon carcinoma cells was also investigated. Purified epithelial cells of normal small and large intestine expressed both hBD-3 and hBD-4 mRNA, with higher expression levels of hBD-3 mRNA. In situ hybridization revealed higher levels of mRNA expression in the crypt- compared to the villus/luminal-compartment. Interferon (IFN)-gamma, but not tumour necrosis factor (TNF)-alpha or IL-1beta, augmented hBD-3 mRNA expression. None of these agents stimulated hBD-4 expression. Colonic epithelial cells from patients with UC displayed a significant increase in hBD-3 and hBD-4 mRNA compared to epithelial cells of controls. In contrast, small intestinal epithelial cells from CD patients did not show increased expression levels compared to the corresponding control cells. Moreover, Crohn's colitis did not show increased expression of hBD-4 mRNA, while the data are inconclusive for hBD-3 mRNA. We conclude that the chronic inflammatory reaction induced in the colon of UC patients enhances hBD-3 and hBD-4 mRNA expression in the epithelium, whereas in CD this is less evident.

  • 17.
    Fahlgren, Anna
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Danielsson, Åke
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Increased expression of antimicrobial peptides and lysozyme in colonic epithelial cells of patients with ulcerative colitis.2003In: Clinical Experimental Immunology, Vol. 131, no 1, p. 90-101Article in journal (Refereed)
  • 18.
    Forsberg, Göte
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Fahlgren, Anna
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hörstedt, Per
    Umeå University, Faculty of Science and Technology, Department of Plant Physiology. Umeå University, Faculty of Science and Technology, Umeå Plant Science Centre (UPSC).
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hernell, Olle
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Presence of bacteria and innate immunity of intestinal epithelium in childhood celiac disease2004In: American Journal of Gastroenterology, ISSN 0002-9270, E-ISSN 1572-0241, Vol. 99, no 5, p. 894-904Article in journal (Refereed)
    Abstract [en]

    OBJECTIVES: Exposure to gliadin and related prolamins and appropriate HLA-DQ haplotype are necessary but not sufficient for contracting celiac disease (CD). Aberrant innate immune reactions could be contributing risk factors. Therefore, jejunal biopsies were screened for bacteria and the innate immune status of the epithelium investigated.

    METHODS: Children with untreated, treated, challenged CD, and controls were analyzed. Bacteria were identified by scanning electron microscopy. Glycocalyx composition and mucin and antimicrobial peptide production were studied by quantitative RT-PCR, antibody and lectin immunohistochemistry.

    RESULTS: Rod-shaped bacteria were frequently associated with the mucosa of CD patients, with both active and inactive disease, but not with controls. The lectin Ulex europaeus agglutinin I (UEAI) stained goblet cells in the mucosa of all CD patients but not of controls. The lectin peanut agglutinin (PNA) stained glycocalyx of controls but not of CD patients. mRNA levels of mucin-2 (MUC2), alpha-defensins HD-5 and HD-6, and lysozyme were significantly increased in active CD and returned to normal in treated CD. Their expression levels correlated to the interferon-gamma mRNA levels in intraepithelial lymphocytes. MUC2, HD-5, and lysozyme proteins were seen in absorptive epithelial cells. beta-defensins hBD-1 and hBD-2, carcinoembryonic antigen (CEA), CEA cell adhesion molecule-1a (CEACAM1a), and MUC3 were not affected.

    CONCLUSIONS: Unique carbohydrate structures of the glycocalyx/mucous layer are likely discriminating features of CD patients. These glycosylation differences could facilitate bacterial adhesion. Ectopic production of MUC2, HD-5, and lysozyme in active CD is compatible with goblet and Paneth cell metaplasia induced by high interferon-gamma production by intraepithelial lymphocytes.

  • 19.
    Forsberg, Göte
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Hernell, O
    Umeå University, Faculty of Medicine, Department of Clinical Sciences.
    Melgar, S
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Israelsson, A
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Paradoxical coexpression of proinflammatory and down-regulatory cytokines in intestinal T cells in childhood celiac disease2002In: Gastroenterology, ISSN 0016-5085, E-ISSN 1528-0012, Vol. 123, no 3, p. 667-678Article in journal (Refereed)
  • 20.
    Frängsmyr, Lars
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Baranov, Vladimir
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Prall, F
    Yeung, Moorix Mo-Wai
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Wagener, C
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Cell- and region-specific expression of biliary glycoprotein and its messenger RNA in normal human colonic mucosa1995In: Cancer Research, ISSN 0008-5472, E-ISSN 1538-7445, Vol. 55, no 14, p. 2963-2967Article in journal (Refereed)
    Abstract [en]

    The localization of biliary glycoprotein (BGP) and its mRNA in normal colonic mucosa was studied by immunohistochemistry and in situ hybridization. BGP mRNA was confined to columnar epithelial cells and expressed abundantly in the superficial mature cells and at low levels in differentiating cells in the upper crypts. Epithelial expression of BGP coincided with that of BGP mRNA. Ultrastructurally, BGP was localized to microfilaments of the fuzzy coat of the columnar cells at the luminal surface and the upper crypts. Additionally, BGP was found in cryptal caveolated cells. The results are consistent with primary transcriptional regulation of BGP production and suggest that BGP synthesis is controlled by the degree of cytodifferentiation. The fuzzy-coat localization of BGP implies a role in nonspecific defense mechanisms against pathogens.

  • 21.
    Frängsmyr, Lars
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Virology.
    Israelsson, Anne
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Teglund, S
    Matsunaga, T
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Evolution of the carcinoembryonic antigen family: Structures of CGM9, CGM11 and pregnancy-specific glycoprotein promoters.2000In: Tumor Biology, ISSN 1010-4283, E-ISSN 1423-0380, Vol. 21, no 2, p. 63-81Article in journal (Refereed)
  • 22.
    Goldsteins, Gundars
    et al.
    Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine).
    Andersson, Karin
    Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine).
    Olofsson, Anders
    Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine).
    Dacklin, Ingrid
    Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine).
    Edvinsson, Åsa
    Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine).
    Baranov, Vladimir
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Sandgren, Ola
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Ophthalmology.
    Thylén, Christina
    Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine).
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Lundgren, Erik
    Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine).
    Characterisation of two highly amyloidogenic mutants of transthyretin1997In: Biochemistry, ISSN 0006-2960, E-ISSN 1520-4995, Vol. 36, no 18, p. 5346-5352Article in journal (Refereed)
    Abstract [en]

    The plasma protein transthyretin (TTR) has the potential to form amyloid under certain conditions. More than 50 different point mutations have been associated with amyloid formation that occurs only in adults. It is not known what structural changes are introduced into the structure of this otherwise stable molecule that results in its aggregation into insoluble amyloid fibrils. On the basis of calculations of the frequency of known mutations over the polypeptide, we have constructed two mutants in the D-strand of the polypeptide. These molecules, containing either a deletion or a substitution at amino acid positions 53−55, were unstable and spontaneously formed aggregates upon storage in TBS (pH 7.6). The precipitates were shown to be amyloid by staining with thioflavin T and Congo Red. Their ultrastructure was very similar to that of amyloid fibrils deposited in the vitreous body of patients with familial amyloidotic polyneuropathy type 1 with an amino acid replacement in position 30 (TTRmet30). Like amyloid isolated from the vitreous body of the eye, the amyloid precipitates generated from the TTR mutants exposed a trypsin cleavage site between amino acid residues 48 and 49, while plasma TTRmet30 isolated from amyloidosis patients as well as wild-type TTR only showed minor trypsin sensitivity. Our data indicate that the mutants we have constructed are similar to amyloid precursors or may share structural properties with intermediates on a pathway leading to amyloid deposits of plasma TTR.

  • 23.
    Hammarström, Marie-Louise
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Lindmark, Gudrun
    Olsson, Lina
    HiloProbe AB.
    Israelsson, Anne
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Biomarkör-mRNA analyser som komplement till histopatologisk undersöknig av lymfkörtelstatus vid kolorektal cancer2020In: Cancerläkaren, ISSN 2003-0290, no 2, p. 33-34Article in journal (Other academic)
  • 24.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Biomarker mRNAs as prognostic tools for lymph node analysis in colorectal cancer2019In: Biomarkers in Medicine, ISSN 1752-0363, E-ISSN 1752-0371, Vol. 13, no 10, p. 801-803Article in journal (Other academic)
  • 25.
    Hammarström, Sten
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Baranov, Vladimir
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Is there a role for CEA in innate immunity in the colon?2001In: Trends in Microbiology, ISSN 0966-842X, E-ISSN 1878-4380, Vol. 9, no 3, p. 119-25Article in journal (Refereed)
    Abstract [en]

    Carcinoembryonic antigen (CEA) is a well known tumor marker associated with the progression of colorectal tumors. The CEA family of glycoproteins has been fully characterized and the function of some of its members is now beginning to be understood. Here, we advance the hypothesis that, rather than functioning in cell adhesion as has been suggested previously, CEA plays a role in protecting the colonic mucosa from microbial invasion. This hypothesis is based on new microscopic, molecular, phylogenetic and microbiological evidence.

  • 26.
    Hammarström, Sten
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Berzins, Klavs
    Biberfeld, Peter
    Engvall, Eva
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Holm, Göran
    Troye-Blomberg, Marita
    Wahlgren, Mats
    Peter Perlmann 1919-2005.2006In: Scandinavian Journal of Immunology, ISSN 0300-9475, E-ISSN 1365-3083, Vol. 63, no 6, p. 487-9Article in journal (Refereed)
  • 27.
    Hedberg, Maria E.
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Israelsson, Anne
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Moore, Edward R. B.
    Svensson-Stadler, Liselott
    Wai, Sun Nyunt
    Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine).
    Pietz, Grzegorz
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Sandström, Olof
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Hernell, Olle
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarstrom, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Prevotella jejuni sp nov., isolated from the small intestine of a child with coeliac disease2013In: International Journal of Systematic and Evolutionary Microbiology, ISSN 1466-5026, E-ISSN 1466-5034, Vol. 63, no 11, p. 4218-4223Article in journal (Refereed)
    Abstract [en]

    Five obligately anaerobic, Gram-stain-negative, saccharolytic and proteolytic, non-spore-forming bacilli (strains CD3 :27, CD3 :28(T), CD3 :33, CD3 :32 and CD3 :34) are described. All five strains were isolated from the small intestine of a female child with coeliac disease. Cells of the five strains were short rods or coccoid cells with longer filamentous forms seen sporadically. The organisms produced acetic acid and succinic acid as major metabolic end products. Phylogenetic analysis based on comparative 16S rRNA gene sequence analysis revealed close relationships between CD3 : 27, CD3 :28(T) and CD3 :33, between CD3 :32 and Prevotella histicola CCUG 55407(T), and between CD3 :34 and Prevotella melaninogenica CCUG 4944B(T). Strains CD3 : 27, CD3 :28(T) and CD3 :33 were clearly different from all recognized species within the genus Prevotella and related most closely to but distinct from P. melaninogenica. Based on 16S rRNA, RNA polymerase) beta-subunit (rpoB) and 60 kDa chaperonin protein subunit (cpn60) gene sequencing, and phenotypic, chemical and biochemical properties, strains CD3 :27, CD3 :28(T) and CD3 :33 are considered to represent a novel species within the genus Prevotella, for which the name Prevotella jejuni sp. nov. is proposed. Strain CD3 : 28(T) (=CCUG 60371(T)=DSM 26989(T)) is the type strain of the proposed novel species. All five strains were able to form homologous aggregates, in which tube-like structures were connecting individual bacteria cells. The five strains were able to bind to human intestinal carcinoma cell lines at 37 degrees C.

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  • 28.
    Hedberg, Maria E
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Moore, Edward RB
    Svensson-Stadler, Liselott
    Hörstedt, Per
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Pathology.
    Baranov, Vladimir
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Hernell, Olle
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Wai, Sun Nyunt
    Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine).
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Lachnoanaerobaculum a new genus in Lachnospiraceae; characterization of Lachnoanaerobaculum umeaense gen. nov., sp. nov., isolated from human small intestine, Lachnoanaerobaculum orale gen. nov., sp. nov., isolated from saliva and reclassification of Eubacterium saburreum (Prevot) Holdeman and Moore 1970 as Lachnoanaerobaculum saburreum comb. nov.2012In: International Journal of Systematic and Evolutionary Microbiology, ISSN 1466-5026, E-ISSN 1466-5034, Vol. 62, no 11, p. 2685-2690Article in journal (Refereed)
    Abstract [en]

    Two new obligately anaerobic Gram-positive, saccharolytic and non-proteolytic spore-forming bacilli (strain CD3:22 and N1) are described. Strain CD3:22 was isolated from a biopsy of the small intestine of a child with celiac disease and strain N1 from the saliva of a healthy young man. The cells of both strains were observed to be filamentous with lengths of approximately 5 to >20 µm, some of them curving and with swellings. The novel organisms produced H2S, NH3, butyric acid and acetic acid as major metabolic end products. Phylogenetic analyses, based on comparative 16S rRNA gene sequencing, revealed close relationships (98 % sequence similarity) between the two isolates, as well as the type strain of Eubacterium saburreum CCUG 28089T and four other Lachnospiraceae bacterium/E. saburreum-like organisms. This group of bacteria were clearly different from any of the 19 known genera in the family Lachnospiraceae. While Eubacterium spp. are reported to be non-spore-forming, reanalysis of E. saburreum CCUG 28089T confirmed that the bacterium, indeed, is able to form spores. Based on 16S rRNA gene sequencing, phenotypic and biochemical properties, CD3:22 (CCUG 58757T) and N1 (CCUG 60305T) represent new species of a new and distinct genus, named Lachnoanaerobaculum, in the family Lachnospiraceae [within the order Clostridiales, class Clostridia, phylum Firmicutes]. Strain CD3:22 is the type strain of the type species, Lachnoanaerobaculum umeaense gen. nov., sp. nov., of the proposed new genus. Strain N1 is the type strain of the species, Lachnoanaerobaculum orale gen. nov., sp. nov. Moreover, E. saburreum CCUG 28089T is reclassified as Lachnoanaerobaculum saburreum comb. nov.

  • 29.
    Hedberg, Maria
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Hernell, Olle
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Baranov, Vladimir
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Wai, Sun Nyunt
    Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine).
    Moore, Edward
    Sahlgrenska Universitetssjukhuset, Göteborgs Universitet.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Clostridiales bacterium CD3:22-an anaerobic spore-forming bacterium isolated from small intestine in a celiac disease patient2010Report (Other academic)
  • 30.
    Ismail, Hager
    et al.
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology. Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry. Department of Clinical Pathology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt.
    AbdelMageed, Manar
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology. Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry. Department of Pathology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt.
    Lindmark, Gudrun
    Institution of Clinical Sciences, Lund University, Helsingborg, Sweden.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Sitohy, Basel
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology. Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Prognostic Significance of GPR55 mRNA Expression in Colon Cancer2022In: International Journal of Molecular Sciences, ISSN 1661-6596, E-ISSN 1422-0067, Vol. 23, no 9, article id 4556Article in journal (Refereed)
    Abstract [en]

    G protein-coupled receptor 55 (GPR55) probably plays a role in innate immunity and tumor immunosurveillance through its effect on immune cells, such as T cells and NK cells. In this study, the prognostic value of GPR55 in colon cancer (CC) was investigated. mRNA expression levels of GPR55 were determined in 382 regional lymph nodes of 121 CC patients with 12 years observation time after curative surgery. The same clinical material had previously been analyzed for expression levels of CEA, CXCL16, CXCL17, GPR35 V2/3 and LGR5 mRNAs. Clinical cutoffs of 0.1365 copies/18S rRNA unit for GPR55 and 0.1481 for the GPR55/CEA ratio were applied to differentiate between the high-and low-GPR55 expression groups. Kaplan–Meier survival analysis and Cox regression risk analysis were used to determine prognostic value. Improved discrimination between the two groups was achieved by combining GPR55 with CEA, CXCL16 or CXCL17 compared with GPR55 alone. The best result was obtained using the GPR55/CEA ratio, with an increased mean survival time of 14 and 33 months at 5 and 12 years observation time, respectively (p = 0.0003 and p = 0.003) for the high-GPR55/CEA group. The explanation for the observed improvement is most likely that GPR55 is a marker for T cells and B cells in lymph nodes, whereas CEA, CXCL16 and CXCL17, are markers for tumor cells of epithelial origin.

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  • 31.
    Lindmark, Gudrun
    et al.
    Department of Clinical Sciences, Lund University, Helsingborg, Sweden; Specialistläkarna, Malmö, Sweden.
    Olsson, Lina
    HiloProbe AB, Umeå, Sweden.
    Sitohy, Basel
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology. Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology.
    Israelsson, Anne
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Blomqvist, Joel
    HiloProbe AB, Umeå, Sweden.
    Kero, Sara
    HiloProbe AB, Umeå, Sweden.
    Roshdy, Tamer
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology. Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology. Department of Molecular Biology, Genetic Engineering, and Biotechnology Research Institute, University of Sadat City, Sadat City, Menoufia, Egypt.
    Söderholm, Mattias
    Department of Surgery, Blekinge Hospital, Karlskrona, Sweden.
    Turi, Annamaria
    Department of Clinical Pathology and Cytology, Blekinge Hospital, Karlskrona, Sweden.
    Isaksson, Jessica
    Department of Clinical Pathology and Cytology, Blekinge Hospital, Karlskrona, Sweden.
    Sakari, Thorbjörn
    Department of Surgical Sciences, Uppsala University Hospital, Uppsala, Sweden; Department of Surgery, Gävle Hospital, Gävle, Sweden.
    Dooper, Michiel
    Department of Clinical Pathology and Cytology, Gävle Hospital, Gävle, Sweden.
    Dafnis, George
    Colorectal Unit, Department of Surgery and Urology, Mälarsjukhuset, Eskilstuna, Sweden.
    Forsberg, Pehr
    Unilabs, Clinical Pathology and Cytology, Mälarsjukhuset, Eskilstuna, Sweden.
    Skovsted, Susanne
    Unit for Surgery, Örnsköldsvik Hospital, Örnsköldsvik, Sweden.
    Walldén, Maria
    Centrum for Surgery, Sundsvall Hospital, Sundsvall, Sweden.
    Kung, Chih-Han
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery. Department of Surgery, Skellefteå Hospital, Skellefteå, Sweden.
    Rutegård, Martin
    Umeå University, Faculty of Medicine, Wallenberg Centre for Molecular Medicine at Umeå University (WCMM). Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Nordmyr, Johanna
    Department of Clinical Pathology, Linköping University Hospital, Linköping, Sweden.
    Muhrbeck, Måns
    Department of Surgery in Norrköping, Linköping University, Norrköping, Sweden; Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    qRT-PCR analysis of CEACAM5, KLK6, SLC35D3, MUC2 and POSTN in colon cancer lymph nodes: An improved method for assessment of tumor stage and prognosis2024In: International Journal of Cancer, ISSN 0020-7136, E-ISSN 1097-0215, Vol. 154, no 3, p. 573-584Article in journal (Refereed)
    Abstract [en]

    One fourth of colorectal cancer patients having curative surgery will relapse of which the majority will die. Lymph node (LN) metastasis is the single most important prognostic factor and a key factor when deciding on postoperative treatment. Presently, LN metastases are identified by histopathological examination, a subjective method analyzing only a small LN volume and giving no information on tumor aggressiveness. To better identify patients at risk of relapse we constructed a qRT-PCR test, ColoNode, that determines levels of CEACAM5, KLK6, SLC35D3, MUC2 and POSTN mRNAs. Combined these biomarkers estimate the tumor cell load and aggressiveness allocating patients to risk categories with low (0, −1), medium (1), high (2) and very high (3) risk of recurrence. Here we present result of a prospective, national multicenter study including 196 colon cancer patients from 8 hospitals. On average, 21 LNs/patient, totally 4698 LNs, were examined by both histopathology and ColoNode. At 3-year follow-up, 36 patients had died from colon cancer or lived with recurrence. ColoNode identified all patients that were identified by histopathology and in addition 9 patients who were undetected by histopathology. Thus, 25% of the patients who recurred were identified by ColoNode only. Multivariate Cox regression analysis proved ColoNode (1, 2, 3 vs 0, −1) as a highly significant risk factor with HR 4.24 [95% confidence interval, 1.42-12.69, P =.01], while pTN-stage (III vs I/II) lost its univariate significance. In conclusion, ColoNode surpassed histopathology by identifying a significantly larger number of patients with future relapse and will be a valuable tool for decisions on postoperative treatment.

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  • 32. Lundqvist, C
    et al.
    Melgar, S
    Yeung, M M
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Intraepithelial lymphocytes in human gut have lytic potential and a cytokine profile that suggest T helper 1 and cytotoxic functions.1996In: Journal of Immunology, ISSN 0022-1767, E-ISSN 1550-6606, Vol. 157, no 5, p. 1926-34Article in journal (Refereed)
    Abstract [en]

    The functional properties of intraepithelial lymphocytes (IEL) in normal human jejunum, ileum, and colon were investigated. Cytokine mRNA expression in IEL and enterocytes was determined by reverse transcriptase-PCR and IFN-gamma+ IEL by immunohistochemistry. Polyclonal activators were used to study proliferation and IFN-gamma secretion of IEL, and an anti-CD3-mediated redirected cytotoxicity assay was used to determine the lytic potential of IEL. Freshly isolated IEL at all three gut levels expressed mRNA for IL-1 beta, IL-2, IL-8, IFN-gamma, and TNF-alpha. Approximately 10% of IEL produced IFN-gamma, suggesting that IEL are immunologically active in vivo, performing similar functions along the intestine. IEL could be stimulated further in vitro to express IL-10, TNF-beta, and TGF-beta 1, while no Th2-type cytokines were induced, suggesting suppressive and cytolytic functions for IEL. All three jejunal IEL subpopulations (CD4-CD8-TCR-gamma delta+, CD4+TCR-alpha beta+, CD8+TCR-alpha beta+) expressed the same four cytokines, IL-2, IL-8, IFN-gamma, and TNF-alpha, indicating that CD4+TCR-alpha beta+ IEL are Th1 cells and that TCR-gamma delta+ IEL and CD8+TCR-alpha beta+ IEL include cytotoxic effector cells. Indeed, freshly isolated jejunal IEL displayed cytolytic activity. IEL were induced to proliferation by anti-CD3/TCR complex mAbs and leukoagglutinin, but not by Con A. There was no correlation between the magnitude of the proliferative response and the amounts of secreted IFN-gamma. Enterocytes expressed IL-1 beta and IL-8, and sometimes TNF-alpha. Although jejunal enterocytes express HLA-DR and hsp60, Ag presentation by these cells may induce anergy since their cytokine profile is different from that of classical APCs.

  • 33.
    Lundqvist, Carina
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Baranov, Vladimir
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Athlin, Leif
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Cytokine profile and ultrastructure of intraepithelial lymphocytes in human gut suggest that they are activated cells with T helper 1 and cytotoxic functionsManuscript (preprint) (Other academic)
  • 34.
    Lundqvist, Carina
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Baranov, Vladimir
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Athlin, Leif
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Intra-epithelial lymphocytes. Evidence for regional specialization and extrathymic T cell maturation in the human gut epithelium1995In: International Immunology, ISSN 0953-8178, E-ISSN 1460-2377, Vol. 7, no 9, p. 1473-1487Article in journal (Refereed)
    Abstract [en]

    The human gut epithelium is a unique immunological compartment, containing substantial amounts of intra-epithelial lymphocytes (IEL) with unknown functions. In this study we show that distinct and unusual subpopulations of IEL are present at different levels of human intestine. IEL phenotypes in normal jejunum, ileum and colon were compared using immunoflow cytometry and immunohistochemistry. The expression of mRNA for recombination-activating gene-1 (RAG-1) in IEL from all three levels was compared using reverse-transcription polymerase chain reaction, and the morphology of IEL in situ was determined using immunoelectron microscopy. Surface marker profiles of isolated intestinal epithelial cells at all three levels were also investigated. On average the proportion of TCR gamma delta IEL was comparable in jejunum than ileum and colon and varied in phenotype with gut level. CD4-CD8-TCR alpha beta IEL dominated in colon but were absent in jejunum. CD8+ TCR alpha beta IEL were present at all levels but only in jejunum did they constitute the majority of all IEL. CD4+ TCR alpha beta IEL were present in similar frequencies at all levels of the gut. In general, the majority of IEL had an activated phenotype (CD45RO+, alpha E beta 7+). Furthermore, IEL exhibited phenotypes which are rare in peripheral blood. The thymocyte markers CD1a and CD1c as well as the NK cell marker CD56 were expressed on a fraction of TCR alpha beta and TCR gamma delta IEL. A small population of 'null' cells (CD45+ TCR/CD#-CD20-CD14-CD15- cells) was also present at equal proportions along the gut. Jejunal but not colonic IEL expressed RAG-1 mRNA suggesting that extrathymic T cell maturation occurs in the epithelium of small intestine. RAG-1 was expressed in CD2+TCR/CD3- and CD3+/TCR-IEL. Ultrastructurally, IEL often formed small clusters and intimate contacts with epithelial cells, suggesting cell cooperation within the epithelium. Some IEL had pseudopodium-like extensions penetrating the epithelial basement membrane suggesting transmigration. Epithelial cells in small intestine but not colon expressed heat shock protein 60 and HLA-DR. CD1a, CD1b and CD1c were not expressed on intestinal epithelial cells at any level. The distinct surface marker profiles of IEL and epithelial cells along small and large intestine suggest functional regional specialization and are compatible with the hypothesis that TCR alpha beta IEL participate in immune reactions to lumenal antigens while TCR gamma delta IEL perform surveillance of the epithelium.

  • 35.
    Lundqvist, Carina
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Baranov, Vladimir
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Teglund, S
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Cytokine profile and ultrastructure of intraepithelial gamma delta T cells in chronically inflamed human gingiva suggest a cytotoxic effector function1994In: Journal of Immunology, ISSN 0022-1767, E-ISSN 1550-6606, Vol. 153, no 5, p. 2302-2312Article in journal (Refereed)
    Abstract [en]

    We have shown that gamma delta T cells in human gingiva have an intraepithelial location and, that in the chronic inflammatory disease periodontitis, the expression of CD45RO and CD8 or CD4 is induced on gamma delta T cells. To study the role of gamma delta T cells in local antibacterial responses, we determined the cytokine profiles of isolated human gingival cells. Different T cell subpopulations, isolated by positive selection with mAb-coated magnetic beads and macrophages, as well as epithelial cells, were analyzed for expression of mRNA for 15 cytokines by reverse transcriptase-PCR. The ultrastructure of gingival gamma delta T cells was also studied. The gamma delta T cells expressed mRNA for IFN-gamma, TNF-alpha, TGF-beta 1, and IL-6. Expression of IFN-gamma was a consequence of inflammation. CD4+ gamma delta T cells expressed IFN-gamma only, whereas CD8+ gamma delta T cells expressed all four cytokines. CD8+ cells expressing IFN-gamma, TNF-alpha, and IL-6 in combination suggest a cytotoxic effector function. Gingival gamma delta T cells contained cytoplasmic electron-dense membrane-bound granules and multivesicular bodies that are ultrastructural characteristics of cytotoxic cells. Epithelial cells from inflamed gingiva expressed HLA-DR, CD1a, CD1c, and heat shock protein 60 on the cell surface. They also expressed mRNA for IL-1 beta, IL-6, IL-8, TNF-alpha, and TGF-beta 1. Thus, epithelial cells may function as accessory cells in immune activation and, at the same time, be target cells for CD8+ gamma delta T cells reactive with CD1 Ag or heat shock protein. These results suggest that gamma delta T cells constitute a first line of defense in gingiva, preventing entrance of pathogens by cytotoxicity against infected and stressed epithelial cells, and by control of epithelial cell growth through secretion of regulatory cytokines.

  • 36.
    Lundqvist, Carina
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Athlin, Leif
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Isolation of functionally active intraepithelial lymphocytes and enterocytes from human small and large intestine1992In: JIM - Journal of Immunological Methods, ISSN 0022-1759, E-ISSN 1872-7905, Vol. 152, no 2, p. 253-263Article in journal (Refereed)
    Abstract [en]

    A mild purification method has been developed for the isolation of human intraepithelial lymphocytes (IEL) and enterocytes from the same individual. The isolation procedure includes mechanical disruption of the mucosal layer, treatment with reducing agent and sedimentation followed by Percoll gradient centrifugation. Finally, epithelial cells are removed from the IEL fraction using magnetic beads coated with the anti-epithelial antigen monoclonal antibody (mAb) BerEP4. Leucocytes are removed from the enterocyte fraction using magnetic beads coated with mAbs directed against common leucocyte antigen (CD45). Using this procedure IEL and enterocytes have been isolated from apparently normal jejunal, ileal and colonic tissue specimens. Recoveries of IEL were 7 x 10(5), 4 x 10(5) and 1 x 10(5)/cm2 mucosa from jejunum, ileum and colon respectively. 1-2 x 10(6) enterocytes/cm2 mucosa were recovered from small intestine while the corresponding value for colonic biopsies was approximately 2 x 10(5) enterocytes/cm2. The IEL fraction was pure as judged by the low percentages of B cells, macrophages and BerEP4 positive cells (less than 4%) present in the purified fraction. The enterocyte fraction contained less than 2% CD45+ cells. The two cell fractions were viable and expanded in vitro. Enterocytes expanded spontaneously while IEL required initial stimulation with mitogens. The isolation procedure described here will make it possible to study the function of human IEL, interactions between IEL and enterocytes and the role of both cell types in local immunity.

  • 37.
    Melgar, S
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Öberg, Åke
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Danielsson, Åke
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Cytolytic capabilities of lamina propria and intraepithelial lymphocytes in normal and chronically inflamed human intestine2004In: Scandinavian Journal of Immunology, ISSN 0300-9475, E-ISSN 1365-3083, Vol. 60, no 1-2, p. 167-177Article in journal (Refereed)
    Abstract [en]

    Cell-mediated lymphocyte cytotoxicity in ileum and colon of patients with ulcerative colitis (UC), Crohn's disease (CD) and controls was investigated. Frequencies of cells expressing perforin and Fas-ligand (FasL) were determined by immunomorphometry. mRNA expression of perforin, granzyme B and FasL in T cells and subsets was assayed by reverse transcriptase-polymerase chain reaction. Cytotoxicity of intraepithelial and lamina propria lymphocytes was analysed without ex vivo activation in three functional assays: (1) anti-CD3-dependent T-cell receptor (TCR)-/CD3-mediated redirected cytotoxicity, (2) Fas-/FasL-mediated TCR-/CD3-independent cytotoxicity and (3) natural killer (NK) cell cytotoxicity. Inflammation in ileum of CD patients caused increased frequency of perforin-expressing cells and enhanced perforin-dependent TCR-/CD3-mediated cytotoxicity. In contrast, lymphocytes in the inflamed colon of UC or Crohn's colitis patients did not display this cytotoxicity nor did lymphocytes of normal colon. Normal colon lymphocytes showed spontaneous Fas-/FasL-mediated cytotoxicity. This activity was retained but not enhanced in inflamed UC colon. In contrast, a significant increase of FasL-expressing cells was seen in situ. Inflammation did not induce NK cell activity in colonic lymphocytes. Intestinal lymphocytes comprise effectors active in two different cytolytic processes. 'Classical' cytotoxic T lymphocytes in small intestine and lymphocytes executing TCR-/CD3-independent FasL-/Fas-mediated killing of unknown biological role present throughout the intestinal mucosa. Ongoing normal cytolytic processes seem to be enhanced by chronic inflammation.

  • 38. Melgar, S
    et al.
    Yeung, M M-W
    Bas, A
    Forsberg, G
    Suhr, O
    Oberg, A
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Danielsson, A
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Over-expression of interleukin 10 in mucosal T cells of patients with active ulcerative colitis.2003In: Clinical and Experimental Immunology, ISSN 0009-9104, E-ISSN 1365-2249, Vol. 134, no 1, p. 127-37Article in journal (Refereed)
    Abstract [en]

    Ulcerative colitis (UC), a chronic inflammatory bowel disease, exhibits pronounced increase of T lymphocytes in the inflamed mucosa. To understand the role of intestinal T lymphocytes in the pathogenesis of UC their cytokine production in the mucosa was analysed. Intestinal T lymphocytes of UC, Crohn's disease and control patients were analysed for cytokine mRNA levels by real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR) directly after isolation without in vitro stimulation. Frequencies of cytokine positive cells were determined in UC and control colon by immunomorphometry. T lymphocytes in normal colon expressed interleukin (IL)-2, interferon (IFN)-gamma, tumour necrosis factor (TNF)-alpha and transforming growth factor (TGF)-beta1, but not IL-4, IL-5 or IL-10. In UC, a highly significant increase in IL-10 mRNA levels in T lymphocytes and an increased frequency of IL-10 positive cells was seen in colon. IL-10 mRNA levels were also elevated in T lymphocytes of the non-inflamed ileum and correlated with disease activity at both locations. CD4+ T lymphocytes were the major source of IL-10 mRNA. IL-2, IFN-gamma and TNF-alpha mRNA levels were decreased in colonic T lymphocytes, and virtually no IL-2, IFN-gamma, TNF-alpha or TGF-beta positive cells were detected in basal lymphoid aggregates. However, scattered IL-10 positive cells were found here. Lamina propria outside the aggregates contained IL-10-, IFN-gamma, TNF-alpha and TGF-beta but not IL-2 positive cells. T cells of UC patients did not express IL-4 or IL-5. Taken, together the data suggest a generalized activation of IL-10 producing CD4+ T cells along the intestine of UC patients. The local environment seems to determine the biological consequences of elevated IL-10.

  • 39. Melgar, Silvia
    et al.
    Bas, Anna
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Human small intestinal mucosa harbours a small population of cytolytically active CD8+ alphabeta T lymphocytes.2002In: Immunology, Vol. 106, no 4, p. 476-485Article in journal (Refereed)
  • 40.
    Melgar, Silvia
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Yeung, M.M.
    Forsberg, G.
    Omholt, K.
    Suhr, Ole
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Öberg, Å.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Danielsson, Åke
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Mucosal T cells of patients with active ulcerative colitis express increased levels of the immune-regulatory cytokine interleukin-10Manuscript (preprint) (Other academic)
  • 41.
    Mincheva-Nilsson, Lucia
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Baranov, Vladimir
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Yeung, M M
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Immunomorphologic studies of human decidua-associated lymphoid cells in normal early pregnancy.1994In: Journal of Immunology, ISSN 0022-1767, E-ISSN 1550-6606, Vol. 152, no 4, p. 2020-32Article in journal (Refereed)
    Abstract [en]

    Human decidual lymphocytes from early, normal pregnancy were characterized in situ with respect to ultrastructure and distribution of subsets. The ultrastructure of isolated decidual gamma delta T cells was also studied. CD45+ cells comprised 11 +/- 2% of all decidual cells. The majority were localized in large lymphoid cell clusters (LCC), near endometrial glands, or as intraepithelial lymphocytes (IEL) in glandular epithelium. The major cell populations in LCC were CD56+TCR-gamma delta+ cells, CD56+ cells, TCR-alpha beta+CD4+ cells, and TCR-alpha beta+CD8+ cells. All expressed activation markers (CD45RO, Kp43, and/or HML-1) and MHC class II Ag (HLA-DR, HLA-DP, and/or HLA-DQ). No B cells were found. Almost all IEL were activated TCR-gamma delta+ cells (CD56+ and CD56-). The glandular epithelial cells expressed heat shock protein 60 at the basolateral side facing the TCR-gamma delta+ IEL. Decidual lymphocytes displayed cytoplasmic processes, microvilli, characteristic cytoplasmic granules, and had intimate contact with neighboring cells. Lymphocytes in the outer rim of LCC and the stroma showed signs of cellular movement. Two main morphotypes of gamma delta T cells could be distinguished. One had single microvilli, membrane-bound granules, and nuclear inclusions. The other had many microvilli, nonmembrane-bound granules and cytoplasmic multivesicular bodies. Our data suggest that LCC are centers of immune reactivity where T and NK cells become activated. The activated cells may guard against infections and undue trophoblast invasion and/or be involved in modulating the local maternal immune system toward unresponsiveness against the semiallogeneic fetus.

  • 42.
    Mincheva-Nilsson, Lucia
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Juto, Per
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Virology.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Human milk contains proteins that stimulate and suppress T lymphocyte proliferation1990In: Clinical and Experimental Immunology, ISSN 0009-9104, E-ISSN 1365-2249, Vol. 79, no 3, p. 463-469Article in journal (Refereed)
    Abstract [en]

    The modulatory effect of human milk proteins from colostrum and late milk on the proliferative response of human T lymphocytes activated by mitogens (OKT3 and leucoagglutinin from Phaseolus vulgaris) and alloantigens was studied. High concentrations (10-100 micrograms/ml) of crude colostral milk proteins had an inhibitory effect on T cell growth while low concentrations (0.1-1 microgram/ml) enhanced T cells growth. In contrast, proteins from late milk did not inhibit T lymphocyte proliferation while the enhancing effect was retained. Colostrum was fractionated by ammonium sulphate precipitation and gel filtration on sepharose 6B. The inhibitory activity was recovered in a protein fraction containing lactoferrin as its major component. Lactoferrin was, however, not responsible for the observed inhibition. On the contrary, lactoferrin in most cases augmented the proliferative response induced by polyclonal activators. The inhibitory activity was found to bind concanavalin A-sepharose suggesting an association with glycoprotein. Inhibitory fractions contained glycoproteins of the following molecular sizes 26, 74/76 (doublet), 84, 145 and 160 kD under reducing conditions. The inhibitory effect appeared to be lymphocyte specific since the active fraction did not inhibit the growth of tissue culture cells (HeLa cells and human fibroblasts) or bacteria. Furthermore, the fraction was not toxic for lymphocytes. The inhibitory colostrum factor may prevent the newborn from overreacting immunologically against the environmental antigens encountered at birth.

  • 43.
    Mincheva-Nilsson, Lucia
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Activated human gamma delta T lymphocytes express functional lactoferrin receptors.1997In: Scandinavian Journal of Immunology, ISSN 0300-9475, E-ISSN 1365-3083, Vol. 46, no 6, p. 609-18Article in journal (Refereed)
    Abstract [en]

    Lactoferrin (Lf), an iron-binding protein in milk, mucosal secretions and neutrophil granules has bactericidal properties and is a source of iron for breast-fed infants. In this paper the authors show that most in vivo activated lymphocytes, i.e. freshly isolated lymphocytes from first trimester human decidua, and most in vitro activated human blood lymphocytes, express lactoferrin receptors (Lf-R), while unstimulated blood lymphocytes do not. All major lymphocyte subsets, i.e. alpha beta T cells, gamma delta T cells, CD8+ T cells, CD4+ T cells, B cells and NK cells, express Lf-R after activation. The proportion of Lf-R expressing activated gamma delta T cells is significantly larger than that of activated alpha beta T cells. Lf-R and transferrin receptors (Tr-R/CD71) show the same kinetics of appearance on activated blood lymphocytes and are, to a large extent, expressed on the same cells. However, 35% of decidual lymphocytes and 15% of activated blood lymphocytes express Lf-R only. Addition of Lf to cultures containing an optimal concentration of Tr augments the proliferative response to polyclonal T cell activators and alloantigens, suggesting that presently used standard culture conditions for in vitro activation are suboptimal in particular for gamma delta T cells. Lf-R on decidual lymphocytes contain bound Lf, which probably is produced locally. The results suggest that Lf is a growth-supporting factor, especially important in local immune responses in the mucosa.

  • 44.
    Mincheva-Nilsson, Lucia
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Human decidual leukocytes from early pregnancy contain high numbers of gamma delta+ cells and show selective down-regulation of alloreactivity.1992In: Journal of Immunology, ISSN 0022-1767, E-ISSN 1550-6606, Vol. 149, no 6, p. 2203-11Article in journal (Refereed)
    Abstract [en]

    The mononuclear lymphoid cell population in human pregnant uterus mucosa, decidua, from early normal pregnancies was studied phenotypically and functionally. The phenotype was determined in situ by immunohistochemistry, and in isolated decidual mononuclear cell preparations by immunofluorescence and flow cytometry. A mild isolation procedure of gentle mechanical disruption followed by density gradient centrifugation was used. Leukocytes comprised a large part of the decidual tissue. They were present in aggregates mainly situated adjacent to the glandular epithelium. In addition, individual leukocytes were present intraepithelially, as well as scattered between the stromal cells and around vessels and lacunes. Four lymphocyte populations of approximately the same size were identified: TCR gamma delta+/CD56+ cells, TCR gamma delta+/CD56- cells, TCR gamma delta-/CD56+ cells, and TCR alpha beta+/CD8+ cells. TCR gamma delta- expressing cells comprised about 60% of the T cells. They were CD4-/CD8-, and about half of the TCR gamma delta+ cells expressed the memory/activation marker CD45RO. The Kp 43 Ag, earlier described on activated CD56+ and TCR gamma delta+ cells in peripheral blood, was essentially only expressed on the TCR gamma delta-/CD56+ cell population in decidua. At least 50% of the TCR alpha beta+ cells were CD8+. The function(s) of either one of these populations might be to prevent immunologic reactions against the fetus, to protect the uterus from unwanted extensive invasion of trophoblasts, or to protect the uteroplacental unit from infection. Decidual T cells did not respond to stimulation by alloantigens or mitogenic anti-CD3 mAb but responded to the same extent as PBMC to mitogenic lectins. The surface density of the TCR/CD3 complex was low on freshly isolated decidual lymphocytes, but could be up-regulated upon stimulation with PMA/Ionomycin. Local selective down-regulation of surface expression of the TCR/CD3 complex and of activation involving this complex might be one of the mechanisms by which a maternal immunologic reaction against the semiallogeneic fetus is prevented.

  • 45.
    Mincheva-Nilsson, Lucia
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Immunomodulatory role of decidual epithelial cells in early human pregnancyManuscript (preprint) (Other academic)
  • 46.
    Mincheva-Nilsson, Lucia
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Kling, M
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Nagaeva, O
    Sundqvist, K G
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Baranov, Vladimir
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Gamma delta T cells of human early pregnancy decidua: evidence for local proliferation, phenotypic heterogeneity, and extrathymic differentiation.1997In: Journal of Immunology, ISSN 0022-1767, E-ISSN 1550-6606, Vol. 159, no 7, p. 3266-77Article in journal (Refereed)
    Abstract [en]

    The uterine mucosa in pregnancy, the decidua, allows placenta formation and survival of the fetus despite the fact that it is semiallogeneic. Decidua contains large numbers of lymphocytes, of which CD56+ cells dominate, followed by T cells expressing either alpha beta or gamma delta TCR. We have investigated the developmental relationship between the CD56- and TCR gamma delta-expressing cells in early pregnancy decidua using dual labeling immunoelectron microscopy, immunoflow cytometry, and cell fractionation. Lymphocyte subpopulations were, in addition, analyzed for expression of the cytokine receptor for IL-7 and c-kit and for mRNA expression of recombinase-activating genes 1 and 2. Four different cell populations could be distinguished: CD56+bright, CD56+dim/TCR gamma delta+low, CD56+dim/TCR gamma delta+high, and TCR gamma delta+low. Recombinase-activating genes 1 and 2 were expressed in the CD56+bright cells and to a limited degree in CD56+dim/TCR gamma delta+low cells. c-kit was preferentially expressed on the CD56+bright cells, while IL-7R was preferentially expressed on CD56+dim/TCR gamma delta+low and CD56+dim/TCR gamma delta+high cells. The CD56+dim TCR gamma delta+low and CD56+dim/TCR gamma delta+high cells displayed the characteristic morphology of large granular lymphocytes, while single positive TCR gamma delta+low cells were usually smaller and did not contain cytoplasmic granules. The gamma delta 1 gene segment was almost exclusively used in the TCR. Gamma delta T cells in mitosis were seen. We suggest that human early pregnancy decidua is a transient site for extrathymic maturation and that the progenitors of TCR gamma delta+ cells are bone marrow-derived immature cells expressing the CD56 (neural cell adhesion molecule) homing receptor.

  • 47.
    Mincheva-Nilsson, Lucia
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Nagaeva, Olga
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Sundqvist, Karl-Gösta
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Baranov, Vladimir
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    gammadelta T cells of human early pregnancy decidua: evidence for cytotoxic potency.2000In: International Immunology, ISSN 0953-8178, E-ISSN 1460-2377, Vol. 12, no 5, p. 585-96Article in journal (Refereed)
    Abstract [en]

    The immune compromise in decidua allows a semiallogeneic fetus to survive without impairing the ability of the maternal immune system to fight infections. Cytotoxic mechanisms are likely to be important in this compromise. Using RT-PCR, immunoflow cytometry and immunoelectron microscopy, the cytotoxic potential of isolated human decidual gammadelta T cells was studied. mRNA for perforin (Pf), granzymes A and B, granulysin and Fas ligand (FasL) was simultaneously expressed in decidual gammadelta T cells. Pf and FasL were not expressed on the cell surface. However, the cells constitutively synthesized Pf and stored it in cytolytic granules. Within the granules Pf mainly resided in the granule core formed by Pf-containing microvesicles. Ultrastructurally, three groups of Pf-containing granules were distinguished. They probably represent different stages of granule maturation in a process where Pf-containing microvesicles first attach to the core cortex and then are translocated across the cortex into the core. Presynthesized FasL was also stored in the core and microvesicles of the cytolytic granules. Upon degranulation by ionomycin/Ca(2+) treatment, FasL was rapidly translocated to the cell surface, demonstrating that its surface expression was not controlled by de novo biosynthesis. Thus decidual gammadelta T cells appear to perform Pf- and FasL-mediated cytotoxicity utilizing a common secretory mechanism based on cytolytic granule exocytosis. The first cytochemical visualization of lipids in the cytolytic granules is provided. These intragranular lipids probably wrap up the core and participate in packaging of the cytotoxic proteins as well as in the killing process. An ultrastructural model of a cytolytic granule is presented.

  • 48. Moore, Edward R.B.
    et al.
    Salvà‐Serra, Francisco
    Jaén‐Luchoro, Daniel
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Hedberg, Maria E.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Lachnoanaerobaculum2021In: Bergey's Manual of Systematics of Archaea and Bacteria (BMSAB), John Wiley & Sons, 2021Chapter in book (Refereed)
    Abstract [en]

    The genus Lachnoanaerobaculum comprises obligately anaerobic, Gram-stain-positive chemoorganotrophic, saccharolytic, and nonproteolytic bacilli. Cells are spore forming, rod shaped, and filamentous, 5 to greater than 20 μm in length, some cells with curving and swelling. All species of the genus grow with glucose as the sole carbon source. All species produce H2S, NH3, butyric acid, acetic acid, and lactic acid as metabolic end products. The predominant cellular fatty acids are C14:0, C16:0, and C18:1 ω7c DMA. The G + C contents of genomic DNA of the species are 35.0–37.8 mol%. Phylogenetic relationships of the species of Lachnoanaerobaculum, based on comparative 16S rRNA gene sequence analyses, indicate that they cluster within the phylum Firmicutes, within the family Lachnospiraceae, and exhibit a clear delineation to the other genera of the family, with a relatively close relationship to Johnsonella species. The first described strain of Lachnoanaerobaculum umeaense, the type species of the genus, was isolated from the jejunal mucosa of a child with coeliac disease. Strains of the species of Lachnoanaerobaculum are typically found in intestinal microbiota and oral microbiota of the human microbiome, isolated from the human gut, saliva, blood, amniotic fluid, and, predominantly, from the oral cavity.

  • 49. Nap, M
    et al.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Börmer, O
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Wagener, C
    Handt, S
    Schreyer, M
    Mach, J P
    Buchegger, F
    von Kleist, S
    Specificity and affinity of monoclonal antibodies against carcinoembryonic antigen.1992In: Cancer Research, ISSN 0008-5472, E-ISSN 1538-7445, Vol. 52, no 8, p. 2329-39Article in journal (Refereed)
    Abstract [en]

    The binding specificities of 52 well-characterized monoclonal antibodies (Mabs) against carcinoembryonic antigen (CEA) from 12 different research groups were studied by immunohistochemistry and immuno flow cytometry. In addition, the binding constant for the interaction between Mab and CEA was determined by a solution-phase assay. Cryostat sections of colon carcinoma and normal colon, stomach, liver, pancreas, and spleen were studied by immunohistochemistry. Peripheral blood granulocytes, monocytes, and lymphocytes were assayed by immuno flow cytometry. The Mabs used here have previously been classified into five essentially nonoverlapping epitope groups (GOLD 1-5) (Cancer Res., 49: 4852-4858, 1989). Most Mabs cross-reacted with different normal tissues, ranging from highly cross-reactive Mabs (positive reaction with 8 of 9 discriminating tissues) to relatively specific Mabs (positive reaction with 1 of 9 discriminating tissues). Five Mabs (10%) were specific, reacting only with colon carcinoma, normal colon mucosa, and normal gastric foveola. There was a correlation between epitope group and binding specificity. Mabs with a high degree of CEA specificity almost exclusively belonged to epitope groups 1, 2, and 3, while highly cross-reactive Mabs belonged to epitope groups 4 and 5. There was no correlation between antibody specificity and affinity for CEA. Specific Mabs with high as well as low affinity were found.

  • 50. Ohlsson, L
    et al.
    Israelsson, A
    Öberg, Å
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Lindmark, G
    Colon cancer: Detection of tumour cells in lymph nodes of colon cancer patients using real-time quantitative reverse transcriptase-polymerase chain reaction (qRT- PCR).2009In: Methods of Cancer Diagnosis, Therapy and Prognosis: Vol. 4: Colorectal Cancer / [ed] M. A. Hayat, Springer, 2009, p. 257-268Chapter in book (Refereed)
12 1 - 50 of 80
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