Problem: Although T lymphocytes at the human vaginal mucosa have been partially characterized, there remains a paucity of information regarding cell-mediated immune mechanisms at this mucosal site. In mice and humans, there are several phenotypic distinctions between vaginal T lymphocytes and those in the peripheral circulation. Recently, we observed as well that the N-terminus of the CD4 protein on murine vaginal T lymphocytes is atypically expressed compared to its systemic counterpart, and that the atypical expression extends to the mRNA level.
Method of study: The purpose of this study was to evaluate the CD4 protein on human vaginal T lymphocytes by flow cytometry and RT-PCR.
Results: Results showed that, in contrast to mice, the CD4 protein on human vaginal and peripheral blood T lymphocytes are similar at both the molecular and protein levels.
Conclusions: These results indicate that based on several differences between human and mouse vaginal T cells, caution is urged when using mice as a model to study human vaginal immunity.