<P> The regulatory T cells (Tregs / ˈtiːrɛɡ /), formerly known as suppressor T cells, are a subpopulation of T cells that modulate the immune system, maintain tolerance to self - antigens, and prevent autoimmune disease . Tregs are immunosuppressive and generally suppress or downregulate induction and proliferation of effector T cells . Tregs express the biomarkers CD4, FOXP3, and CD25 and are thought to be derived from the same lineage as naïve CD4 cells . Because effector T cells also express CD4 and CD25, Tregs are very difficult to effectively discern from effector CD4+, making them difficult to study . Recent research has found that the cytokine TGFβ is essential for Tregs to differentiate from naïve CD4+ cells and is important in maintaining Treg homeostasis . </P> <P> Mouse models have suggested that modulation of Tregs can treat autoimmune disease and cancer and can facilitate organ transplantation . Their implications for cancer are complicated . Tregs tend to be upregulated in individuals with cancer, and they seem to be recruited to the site of many tumors . Studies in both humans and animal models have implicated that high numbers of Tregs in the tumor microenvironment is indicative of a poor prognosis, and Tregs are thought to suppress tumor immunity, thus hindering the body's innate ability to control the growth of cancerous cells . Recent immunotherapy research is studying how regulation of T cells could possibly be utilized in the treatment of cancer . </P>

What is the role of suppressor t cells
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