CD3+CD20+ T cells and their roles in human diseases

Abstract CD3 + CD20 + T cells are a population of CD3 + T cells co-expressing CD20 that make up to ∼3–5% of the CD3 + T-cell compartment in the peripheral blood of human beings. In healthy individuals, CD3 + CD20 + T cells are heterogeneous for containing a lower proportion of CD4 + cells, but produce higher levels of IL-17A and/or IFN-γ than those of CD3 + CD20 − T cells. Recently, emerging studies have shown a pathogenic behavior of CD3 + CD20 + T cells in autoimmune diseases and CD20 + T-cell malignancies, and patients with the diseases may benefit from anti-CD20 immunotherapy to deplete these cells. However, CD3 + CD20 + T cells may also play a protective role in ovarian cancer and HIV infection for their strong propensity to IFN-γ production. In this review, we will describe the current knowledge about CD3 + CD20 + T-cell biology, and discuss their functional roles in autoimmune diseases as well as cancer and infectious diseases.