CD33 and autoimmune thrombocytopenic purpura: Our findings are in line with a previous report describing an increase in CD33+/CD11b+/HLA-DR− MDSC in immune thrombocytopenia (ITP) patients treated with both IVIg and dexamethasone after 6 days [76], and also agree with an enhancement of CD33+/CD11b+/HLA-DR− cells in spleen cells from ITP patients exposed in vitro to IVIg for 90 h [77].