CD8⁺CXCR5⁺ T cells regulate pathology in the genital tract.

We have identified a CD8⁺CXCR5⁺ T cell that prevents the development of oviduct dilation following C. muridarum genital infection. Phenotypic studies show that CD8⁺CXCR5⁺ cells express markers of T regulatory cells (FoxP3, CD25, and GITR) but do not express a necessary component of cytotoxic cells (perforin). Cxcr5⁻/⁻ mice have significantly lower numbers of CD8⁺ cells and lack the CD8⁺CXCR5⁺ population while the total number of CD4⁺ cells is equivalent between mouse strains. The transfer of CD8⁺ splenocytes from WT mice reduces the oviduct dilation seen in Cxcr5⁻/⁻ mice following C. muridarum infection. Future studies will investigate the mechanism by which this cell type regulates genital tract pathology.