fig3

Figure 3. IL-31 induces the polarization of naive CD4⁺ T cells toward Th2 by upregulating the STAT6 signaling pathway. (A) ELISA measuring changes in IL-4 expression in naive CD4⁺ T cells induced by rh-IL-31 (n = 3); (B) The increase in IL-4 expression in naive CD4⁺ T cells mediated by FAP⁺CAFs can be blocked by IL-31 antibodies (n = 3); (C) Western blot analysis of the effects of rh-IL-31 on signaling pathway activity in naive CD4⁺ T cells; (D) Western blot results showing that the increase in pSTAT6 expression in naive CD4⁺ T cells mediated by FAP⁺CAFs can be blocked by IL-31 antibodies; (E and F) ELISA measuring the effects of relevant small molecule inhibitors on the increase in IL-4 expression in naive CD4⁺ T cells mediated by IL-31 (n = 3); (G) Flow cytometric analysis of whether the increase in CCR4 expression in naive CD4⁺ T cells mediated by IL-31 can be blocked by pSTAT6 inhibitor. ^**P < 0.01; ^***P < 0.001; bars: means ± standard deviation. CAFs: Cancer-associated fibroblasts.