Single nutrient deficiency and cell-mediated immune responses. III. Vitamin A

Weanling rats were fed vitamin-A deficient diet for 3–4 weeks until the weight plateaued. The weight of the thymus and the spleen and the number of mononuclear cells contained in these lymphoid organs were similar in vitamin A-deficient animals and pair-fed controls. Lymphocyte stimulation response to phytohemagglutinin and antibody plaque forming cell number were decreased. Serum thymine hormone activity in the vitamin A-deficient group and pair-fed controls was comparable. These data confirm the important role of vitamin A in modulating cell-mediated immunity.