The<unk> s <unk> s or<unk> <unk> s), formerly known as suppressor<unk> s, are a subpopulation of<unk> s that modulate the immune system, maintain tolerance to self-antigens, and prevent autoimmune disease.<unk> <unk> s are immunosuppressive and generally suppress or downregulate induction and proliferation of effector<unk> s.<unk> <unk> s express the biomarkers CD4, FOXP3, and CD25 and are thought to be derived from the same lineage as naïve CD4+<unk> s. Because effector<unk> s also express CD4 and CD25,<unk> <unk> s are very difficult to effectively discern from effector CD4+, making them difficult to study. Research has found that the cytokine transforming growth factor beta (TGF-β) is essential for<unk> <unk> s to differentiate from naïve CD4+<unk> s and is important in maintaining<unk> <unk>  homeostasis. Mouse models have suggested that modulation of<unk> <unk> s can treat autoimmune disease and cancer and can facilitate organ transplantation and wound healing. Their implications for cancer are complicated.<unk> <unk> s 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<unk> <unk> s in the tumor microenvironment is indicative of a poor prognosis, and<unk> <unk> s are thought to suppress tumor immunity, thus hindering the body's innate ability to control the growth of cancerous<unk> s. Immunotherapy research is studying how regulation of<unk> s could possibly be utilized in the treatment of cancer.
Regulatory T cell
Regulatory B cell
Cytokine-induced killer cell
Natural killer T cell
Memory B cell
Naive T cell
Nonspecific immune cell
Natural killer cell