Diminished CD103 (αEβ7) Expression on Resident T Cells from the Female Genital Tract of HIV-Positive Women.

Background: Tissue resident memory T cells (TrM) provide an enhanced response against infection at mucosal surfaces, yet their function has not been extensively studied in humans, including the female genital tract (FGT).

Methods: Using polychromatic flow cytometry, we studied TrM cells, defined as CD62L-CCR7-CD103CD69 CD4 and CD8 T cells in mucosa-derived T cells from healthy and HIV-positive women.

Results: We demonstrate that TrM are present in the FGT of healthy and HIV-positive women. The expression of the mucosal retention receptor, CD103, from HIV-positive women was reduced compared to healthy women and was lowest in women with CD4 counts < 500 cells/mm. Furthermore, CD103 expression on mucosa-derived CD8 T cells correlated with antigen-specific IFN-γ production by mucosal CD4 T cells and was inversely correlated with T-bet from CD8CD103 mucosa-derived T cells.

Conclusions: These data suggest that CD4 T cells, known to be impaired during HIV-1 infection and necessary for the expression of CD103 in murine models, may play a role in the expression of CD103 on resident T cells from the human FGT.