IL4 and colitis: Moreover, to monitor the secretory proteins related to colitis, we assessed the concentrations of cytokines in mouse serum using an ELISA kit, and the results showed that BPIS treatment significantly reduced the level of inflammatory factors TNF-α, IL-1β, and IL-6 (Figures 2B–D) but elevated the level of the Treg-type cytokines IL-10 (Figure 2E), Th2-type cytokines IL-4 (Figure 2F), and IL-5 (Figure 2G).