Figure 4.

The role of RA in the regulation of CD4+ T cells and gut-homing molecules. Splenic CD4⁺ T cells were isolated from NOD/ShitJ mice and then cultured under Th17 differentiation conditions with or without RA for 3 days. (A) Bar graphs show average frequencies of CD4⁺IL-17⁺ (Th17), CD4⁺CXCR5⁺ IL-17⁺ (T_FH17), and CD4⁺CD25⁺Foxp3⁺ (Treg) cells under the indicated conditions. (B) Bar graph shows average levels of secretory IL-17, as determined in the culture supernatant by enzyme-linked immunosorbent assay (ELISA) under the indicated conditions. (C) Bar graphs show average frequencies of CCR9⁺ (top and left), α4β7⁺ (top and right), and CCR9⁺α4β7⁺ (bottom) in CD4⁺IL-17⁺ cells under the indicated conditions. Data are means ± SEM from three independent experiments. *p < 0.05, **p < 0.01, ***p < 0.001.