title: CD4+ CD25+ suppressor T cells: more questions than answers.
abstract: Several mechanisms control discrimination between self and non-self, including the thymic deletion of autoreactive T cells and the induction of anergy in the periphery. In addition to these passive mechanisms, evidence has accumulated for the active suppression of autoreactivity by a population of regulatory or suppressor T cells that co-express CD4 and CD25 (the interleukin-2 receptor alpha-chain). CD4+ CD25+ T cells are powerful inhibitors of T-cell activation both in vivo and in vitro. The enhancement of suppressor-cell function might prove useful for the treatment of immune-mediated diseases, whereas the downregulation of these cells might be beneficial for the enhancement of the immunogenicity of vaccines that are specific for tumour antigens.
authors.affiliation: Laboratory of Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA. EShevach@niaid.nih.gov
authors.forename: Ethan M
authors.initials: EM
authors.lastname: Shevach
mesh_terms: D000069594:Abatacept; D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology; D015703:Antigens, CD; D000943:Antigens, Differentiation / Q000378:metabolism; D015704:CD4 Antigens / Q000378:metabolism*; D060908:CTLA-4 Antigen; D016207:Cytokines / Q000378:metabolism; D006706:Homeostasis; D006801:Humans; D007108:Immune Tolerance; D018796:Immunoconjugates; D066298:In Vitro Techniques; D008213:Lymphocyte Activation; D051379:Mice; D018448:Models, Immunological; D051381:Rats; D015375:Receptors, Interleukin-2 / Q000378:metabolism*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*; D013950:Thymus Gland / Q000166:cytology / Q000276:immunology; D016212:Transforming Growth Factor beta / Q000378:metabolism
chemical_list: D015703:Antigens, CD; D000943:Antigens, Differentiation; D015704:CD4 Antigens; D060908:CTLA-4 Antigen; C556706:CTLA4 protein, human; C556707:Ctla4 protein, mouse; D016207:Cytokines; D018796:Immunoconjugates; D015375:Receptors, Interleukin-2; D016212:Transforming Growth Factor beta; D000069594:Abatacept