CD33 and inflammatory bowel disease: Overall, the above studies demonstrated the accumulation of MDSCs in human IBD, and revealed that CD14+HLA-DR-/low MDSCs from the peripheral blood of IBD patients inhibited anti-CD3/CD28–stimulated autologous mononuclear cells while CD33+CD15+CD14–HLA-DR–/low MDSCs promoted the proliferation of autologous T cells.