ICOS and colitis: In contrast with mice in the DSS group, the numbers of CD4+CXCR5+ BCL-6+ (Figures 4A–C), CD4+CXCR5+ICOS+ (Figures 3A,B,F), and CD4+CXCR5+PD-1+ (Figures 4A,B,E) T cells were decreased, and CD4+CXCR5+Blimp-1+ T cells (Figures 4A,B,D) were significantly increased after colitis was treated with SSP and 5-ASA for 7 days.