title: Memory T cells need CD28 costimulation to remember.
abstract: The activation and expansion of naïve T cells require costimulatory signals provided by CD28 and TNF family members. In contrast, for many years it was believed that memory T cells do not require CD28 costimulation for expansion during secondary responses. This was based on in vitro experiments that suggested the re-activation of memory T cells is somewhat independent of costimulation. Recent in vivo evidence, however, has challenged this and shown that both CD4+ and CD8+ memory T cells require CD28 costimulation for maximal expansion and pathogen clearance. This requirement has important implications for host immunity, vaccine development and immunotherapeutics.
authors.affiliation: Drexel University College of Medicine, Department of Microbiology and Immunology, 2900 Queen Lane, Philadelphia, PA 19129, United States. Alina.Boesteanu@Drexelmed.edu
authors.forename: Alina C
authors.initials: AC
authors.lastname: Boesteanu
authors.forename: Peter D
authors.initials: PD
authors.lastname: Katsikis
mesh_terms: D000375:Aging / Q000276:immunology; D000818:Animals; D001327:Autoimmune Diseases / Q000276:immunology; D018106:CD28 Antigens / Q000276:immunology / Q000378:metabolism*; D002454:Cell Differentiation; D006084:Graft Rejection / Q000276:immunology; D006801:Humans; D007156:Immunologic Memory; D007239:Infections / Q000276:immunology; D008213:Lymphocyte Activation / Q000276:immunology; D009369:Neoplasms / Q000276:immunology* / Q000473:pathology; D020239:Receptor Cross-Talk / Q000276:immunology; D015398:Signal Transduction / Q000276:immunology; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology / Q000378:metabolism*; D048069:Tumor Necrosis Factors / Q000276:immunology*
chemical_list: D018106:CD28 Antigens; D048069:Tumor Necrosis Factors