Retinoic acid imprints gut-homing specificity on T cells.

Mitsubishi Kagaku Institute of Life Sciences, 11 Minamiooya, Machida-shi, Tokyo 194-8511, Japan.
Immunity (Impact Factor: 19.75). 11/2004; 21(4):527-38. DOI: 10.1016/j.immuni.2004.08.011
Source: PubMed

ABSTRACT For a preferential homing of T cells to the gut, expression of the integrin alpha4beta7 and the chemokine receptor CCR9 is essential and is induced by antigenic stimulation with dendritic cells from the gut-associated lymphoid organs. Here, we show that the vitamin A (retinol) metabolite, retinoic acid, enhances the expression of alpha4beta7 and CCR9 on T cells upon activation and imprints them with the gut tropism. Dendritic cells from the gut-associated lymphoid organs produced retinoic acid from retinol. The enhanced alpha4beta7 expression on T cells by antigenic stimulation with these dendritic cells was suppressed by the retinal dehydrogenase inhibitor citral and the retinoic acid receptor antagonist LE135. Accordingly, vitamin A deficiency caused a reduction in alpha4beta7(+) memory/activated T cells in lymphoid organs and a depletion of T cells from the intestinal lamina propria. These findings revealed a novel role for retinoic acid in the imprinting of gut-homing specificity on T cells.

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