CD4 and inflammatory bowel disease: Given that several studies have demonstrated that IL10-secreting regulatory T cells (Treg) confer significant protection against IBD by decreasing the activation of autoreactive Th1 cells35 and analogue 5 increased colonic IL10 levels (Figs. 3c, 4c and 5c) and MLN IL10-secreting CD4 cells (Fig. 6b), we examined the capacity of this analogue to increase the Treg population in colitic mice.