FIGURE 4.

RA suppressed Th2 development in the presence of TGF-β1. A, naïve T cells were cultured under the Th0/iTreg condition with the indicated cytokines, 10 nm RA, with or without IL-4 for 3 days. The Foxp3 levels were determined by fluorescence-activated cell sorting, and the percentage of Foxp3⁺ cells is shown in the graph. B, effect of RA on Th2 development. Naïve T cells were cultured under the indicated conditions for 3 days, and then the cells were restimulated with plate-bound anti-CD3 Ab for 24 h. IL-4 production was determined by enzyme-linked immunosorbent assay (ELISA). IL-4 and GATA3 mRNA expression was determined by real-time PCR.