OBJECTIVETo study the effects of vitamin A on the development of T lymphocytes in peripheral blood and small intestine and on the cytokine response of intestinal mucosa in mice.

METHODSTwenty young mice were randomly fed with forage containing vitamin A 250 or 4 IU/g (n=10 each). Three weeks later, the levels of CD4+ CD25+ T subsets in peripheral blood and intestinal mucosa were measured by flow cytometry. The levels of cytokines IFN-γ, IL-4, IL-17 and IL-23 in stool were measured using ELISA.

RESULTSThe levels of CD4+ CD25+ T subsets in peripheral blood and intestinal mucosa in the 250 IU/g vitamin A group were significantly higher than those in the 4 IU/g vitamin A group (P<0.05). The IL-4 level in stool increased, in contrast, the IL-23 level in stool decreased significantly in the 250 IU/g vitamin A group when compared with the 4 IU/g vitamin A group (P<0.05).

CONCLUSIONSvitamin A may promote the development of CD4+ CD25+ T lymphocytes in peripheral blood and small intestine. Moreover, it may be involved in intestinal mucosa-associated immune response by regulating cytokines IL-4 and IL-23.