Expansion of CD4+CD25+ helper T cells without regulatory function in smoking and COPD
2011 (English)In: Respiratory research (Online), ISSN 1465-993X, Vol. 12, no 74, 8- p.Article in journal (Refereed) Published
Background: Regulatory T cells have been implicated in the pathogenesis of COPD by the increased expression of CD25 on helper T cells along with enhanced intracellular expression of FoxP3 and low/absent CD127 expression on the cell surface.
Method: Regulatory T cells were investigated in BALF from nine COPD subjects and compared to fourteen smokers with normal lung function and nine never-smokers.
Results: In smokers with normal lung function, the expression of CD25+CD4+ was increased, whereas the proportions of FoxP3+ and CD127+ were unchanged compared to never-smokers. Among CD4+cells expressing high levels of CD25, the proportion of FoxP3+ cells was decreased and the percentage of CD127+ was increased in smokers with normal lung function. CD4+CD25+ cells with low/absent CD127 expression were increased in smokers with normal lung function, but not in COPD, when compared to never smokers.
Conclusion: The reduction of FoxP3 expression in BALF from smokers with normal lung function indicates that the increase in CD25 expression is not associated with the expansion of regulatory T cells. Instead, the high CD127 and low FoxP3 expressions implicate a predominantly non-regulatory CD25+ helper T-cell population in smokers and stable COPD. Therefore, we suggest a smoking-induced expansion of predominantly activated airway helper T cells that seem to persist after COPD development.
Place, publisher, year, edition, pages
London: BioMed Central , 2011. Vol. 12, no 74, 8- p.
Respiratory Medicine and Allergy
IdentifiersURN: urn:nbn:se:umu:diva-49393DOI: 10.1186/1465-9921-12-74PubMedID: 21651772OAI: oai:DiVA.org:umu-49393DiVA: diva2:455582