Sex differences of subpopulation composition of lymphocytes in the peripheral blood in experimental acute and chronic ulcerative colitis

Abstract

We studied sex differences lymphocytes subpopulations of peripheral blood in adult C57Bl/6 mice during acute and chronic colitis, induced with 1% DSS. We measured subpopulations of lymphocytes with flow cytometry. We showed that in the control group the female mice had statistically significantly higher values of the relative number of regulatory and cytotoxic T lymphocytes comparing to the males. During acute colitis the females showed an increase in the relative number of Thelpers and a decrease of cytotoxic Tlymphocytes, which reflects the activation of immune response. The males had a decrease in the absolute number of leukocytes, lymphocytes and cytotoxic and regulatory T lymphocytes, probably because of an increase in migration of these cells to the inflammation locus and local lymph nodes. In chronic colitis the females had a decrease in the absolute number of leukocytes, lymphocytes, T helpers, cytotoxic T lymphocytes and B lymphocytes when comparing with acute colitis. During chronic colitis the males had a decrease in the absolute number of T helpers and B lymphocytes but an increase of regulatory T cells in comparison with the control group; in comparison with acute colitis the males with chronic colitis had higher relative and absolute number of regulatory T cells. The increase of T regulatory lymphocytes is due to an increase in their proliferation rate in the thymus and increase of their migration to the inflammatory locus – the colon. Future clinical studies may be based on these results, which show that the treatment of colitis, especially with immunotropic agents, must take sex differences into account.