title: The role of CD28 and cytotoxic T-lymphocyte antigen-4 (CTLA-4) in regulatory T-cell biology.
abstract: The profound influence of CD28 and cytotoxic T-lymphocyte antigen-4 (CTLA-4) on T-cell immunity has been known for over a decade, yet the precise roles played by these molecules still continue to emerge. Initially viewed as molecules that provide cell-intrinsic costimulatory and inhibitory signals, recent evidence suggests that both CD28 and CTLA-4 are also important in the homeostasis and function of a population of suppressive cells, termed regulatory T cells (Tregs). Here we review the main features of the CD28 and CTLA-4 system and examine how these impact upon Treg biology.
authors.affiliation: MRC Centre for Immune Regulation, University of Birmingham Medical School, Birmingham, UK. D.M.Sansom@bham.ac.uk
authors.forename: David M
authors.initials: DM
authors.lastname: Sansom
authors.forename: Lucy S K
authors.initials: LS
authors.lastname: Walker
mesh_terms: D015703:Antigens, CD; D000943:Antigens, Differentiation / Q000235:genetics / Q000378:metabolism*; D018106:CD28 Antigens / Q000378:metabolism*; D060908:CTLA-4 Antigen; D002448:Cell Adhesion / Q000276:immunology; D002465:Cell Movement / Q000276:immunology; D051858:Forkhead Transcription Factors / Q000378:metabolism; D006801:Humans; D008024:Ligands; D008213:Lymphocyte Activation; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*; D016212:Transforming Growth Factor beta / Q000378:metabolism
chemical_list: D015703:Antigens, CD; D000943:Antigens, Differentiation; D018106:CD28 Antigens; D060908:CTLA-4 Antigen; C556706:CTLA4 protein, human; C418974:FOXP3 protein, human; D051858:Forkhead Transcription Factors; D008024:Ligands; D016212:Transforming Growth Factor beta