Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE credits
Background: Periodontitis, peri-implantitis, and endodontic infections are oral diseases driven by polymicrobial communities, in which Filifactor alocis is commonly found. One of its virulence factors is the exotoxin FtxA, which is unknown in its effect on surrounding tissue. Recent studies showed expanded lifespan of neutrophils in the presence of Filifactor alocis by avoidance of apoptosis.
Aim: The aim of this study was to examine whether FtxA from Filifactor alocis affects apoptosis in THP-1 cells.
Material and methods: THP-1 cells cultivated in RPMI with PMA to make the cells adhere to the bottom of the dish and differentiate to macrophage-like cells. The cells were then stimulated with Staurosporine, Fa1, Fa12 and FtxA and incubated for 6 hours and 24 hours respectively. The proteins were then extracted and used for BCA assay to estimate the protein concentration to be able to run a Western Blot.
Results: At 6 hours all different stimulations of the THP-1 cells showed faint bands of the proteins, except for GAPDH which showed a clear band in all different samples. At 24-hour stimulation with only Staurosporine, or with Staurosporine and Fa12, respectively, clear bands were present of the proteins. At 24-hour stimulation with Staurosporine and Fa1 or with Staurosporine and FtxA, respectively, faint or nearly absent bands were present of the proteins.
Conclusion: The results from this pilot study suggest that FtxA may stop caspase activation and thereby prevent apoptosis. However, the effect of FtxA was only observed after 24 hours, and further investigation is needed to solidify these findings.
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