Characterization of neutrophils and T lymphocytes associated with the murine vaginal epithelium

The murine vaginal epithelium was investigated as a site for the presence of leukocytes, using monoclonal antibodies to various cell surface antigens in conjunction with multiparameter flow cytometry. Two types of CD45⁺ leukocytes were found with distinct expression of Mac-1 and CD3. The Mac-1⁺ cells are neutrophils, as evidenced by their multilobed nuclei. Previously, we have shown that αβ T cells, γδ T cells, and a novel population of Thy- 1⁺CD3^- cells are associated with the vaginal epithelium. In addition, a small number of MHC class II⁺ cells were detected. B cells, macrophages, and natural killer cells were not detected and do not contribute to the cellular immunity of the vagina. It is known that the lumen of the murine vagina is lined with stratified squamous epithelium, which undergoes marked changes during the estrous cycle. The cellular number and composition of dissociated epithelial associated Mac-1⁺ cells, αβ T cells, γδ T cells, and Thy- 1⁺CD3^- cells did not change significantly during the estrous cycle or under the influence of the ovarian hormones 17 β-estradiol and progesterone. In summary, this study characterizes the leukocytes involved in mucosal immunity of the murine vagina.