The vitamin A metabolite retinoic acid (RA) seems to be a double-edge sword in CD4+ T cell biology, sustaining the development of foxp3+ Treg cells, but also being essential for the stability of the Th1 lineage. Here we explored the role of RA signalling in CD4+ T cells during the development of intestinal inflammation in the T cell transfer colitis model. RA signalling-deficient CD4+ T cells are less potent at inducing intestinal inflammation compared to their RA signalling-proficient counterparts and exhibit a differentiation skewing towards more IL-17+ and foxp3+ cells, while their capacity to differentiate into Th1 cells is compromised. In vitro studies confirm the inefficacy of RA signalling-deficient T cells to generate bona fide Th1 cells and demonstrate their aberrant increased RORγt expression, while their Th17 differentiation remains unaffected. Surprisingly, RA signalling-deficient and –proficient Tregs are equally competent to inhibit colitis development. Together our results indicate that RA, through its receptor RARα, negatively regulates the early expansion of CD4+ T cells during colitis and is necessary for the generation of colitogenic Th1/Th17 cells, while it is dispensable for the protective function of Treg cells. We are currently deciphering the mechanisms of these effects of RA on CD4+ T cells.
|Number of pages||1|
|Publication status||Published - 2016|
|Event||10th European Mucosal Immunology Group meeting - Copenhagen, Denmark|
Duration: 19 Oct 2016 → 21 Oct 2016
Conference number: 10
|Conference||10th European Mucosal Immunology Group meeting|
|Period||19/10/2016 → 21/10/2016|