[Research progress in heterogeneity of human CD4(+)FOXP3(+)T cells]

It is now established that CD4(+)CD25(+)regulatory T (Treg) cells expressing transcription factor FOXP3, a regulatory subpopulation of T cells, is indispensable for the maintenance of immunological self-tolerance and immune homeostasis. FOXP3 expression in Treg cells is specific and it is the key control factor for the development, activation and function of Treg cells. At present, CD4(+)FOXP3(+)T lymphocytes are often used to define Treg cells for scientific research. But recent studies show that human CD4(+)FOXP3(+)T cells are phenotypically and functionally heterogeneous, including suppressive and non suppressive T cells. The different functions of these cell subsets can be distinguished by phenotypic differences. This review discusses the recent research progress about phenotypic characteristics and functional heterogeneity of CD4(+)FOXP3(+)T cell subsets.