CD28 and inflammatory bowel disease: In this study, CD3+, CD4+, CD8+, CD28+, and naive T cells were inhibited in high-dose cyclophosphamide-induced immunotoxicity mice after treatment with HEP3 (Figure 4), and also the immunohistochemistry of colon tissues in the IBD model rats showed the same results that Foxp3, IL-10, TNF-α, and NF-κB p65 improved to near normal (Figures 1C and 9), indicating that HEP3 might improve the immune function via regulating the proliferation and differentiation of T cells with the help of gut microbiota, but much more details need to be revealed.