The interaction of vitamin A deficiency and rotavirus infection in the mouse.

Weanling mice were fed on a control diet ad lib., a vitamin A-deficient diet ad lib. or pair-fed to the intake of the vitamin A-deficient group. Vitamin A deficiency was induced by 63-70 d of age. On day 77 mice were given 30 microliters rotavirus/mouse orally and examined histologically 1 week later. There were no changes in relative liver weight in any of the groups, but following infection animals deficient in vitamin A showed a significant increase in spleen weight compared with the other groups. The relative weight of the thymus was reduced by vitamin A deficiency, in both non-infected and infected animals. The histology of the spleen, thymus and small intestine was similar in all three dietary groups before infection. The number of goblet cells per duodenal villus in vitamin A-deficient animals was significantly lower than that of control and pair-fed animals. In the small intestine of vitamin A-deficient animals, rotavirus infection caused dramatic changes to the mucosa, with almost complete destruction of the tips of the villi, but control and pair-fed animals had normal villi. It is concluded that although rotavirus infection and vitamin A-deficiency cause few changes alone, in their action together there is significant destruction of the mucosal barrier of the small intestine.