Transcriptional profiling of small intestinal lamina propria Dendritic cells by microarray

CD103+CD11b+ dendritic cells (DC) are unique to the intestine, but the factors governing their differentiation are unclear. Here we show that transforming growth factor receptor 1 (TGF beta 1) has an indispensable, cell intrinsic role in the development of these cells. Deletion of Tgfbr1 results in markedly fewer intestinal CD103+CD11b+ DCs and a reciprocal increase in the CD103–CD11b+ DC subset. Transcriptional profiling identifies markers that define the CD103+CD11b+ DC lineage, including CD101, TREM1 and Siglec-F, and shows that the absence of CD103+CD11b+ DCs in CD11c-Cre.Tgfbr1fl/fl mice reflects defective differentiation from CD103–CD11b+ intermediaries, rather than an isolated loss of CD103 expression. The defect in CD103+CD11b+ DCs is accompanied by reduced generation of antigen-specific, inducible FoxP3+ regulatory T (Treg) cells in vitro and in vivo, and by reduced numbers of endogenous TH17 cells in the intestinal mucosa. Thus, TGF beta 1 mediated signalling may explain the tissue-specific development of these unique DCs. Dendritic cell and Macrophage subpopoulations were isolated from the Small Intestine of Healthy Steady State mice, RNA was isolated and sent for microarray analysis