title: A novel human CD4+ T-cell inducer subset with potent immunostimulatory properties.
abstract: The complexity of immunoregulation has focused attention on the CD4+ T "suppressor" regulatory cell (Treg), which helps maintain balance between immunity and tolerance. An immunoregulatory T-cell population that upon activation amplifies cellular immune responses was described in murine models more than 30 years ago; however, no study has yet identified a naturally occurring T "inducer" cell type. Here, we report that the ectoenzyme CD39/NTPDase1 (ecto-nucleoside triphosphate diphosphohydrolase 1) helps to delineate a novel population of human "inducer" CD4+ T cells (Tind) that significantly increases the proliferation and cytokine production of responder T cells in a dose-dependent manner. Furthermore, this unique Tind subset produces a distinct repertoire of cytokines in comparison to the other CD4+ T-cell subsets. We propose that this novel CD4+ T-cell population counterbalances the suppressive activity of suppressor Treg in peripheral blood and serves as a calibrator of immunoregulation.
authors.affiliation: Division of Experimental Medicine, Department of Medicine, University of California San Francisco, and HIV/AIDS Division, San Francisco General Hospital, San Francisco, CA 94110, USA. lndhlovu@medsfgh.ucsf.edu
authors.forename: Lishomwa C
authors.initials: LC
authors.lastname: Ndhlovu
authors.forename: Fabio E
authors.initials: FE
authors.lastname: Leal
authors.forename: Ijeoma G
authors.initials: IG
authors.lastname: Eccles-James
authors.forename: Aashish R
authors.initials: AR
authors.lastname: Jha
authors.forename: Marion
authors.initials: M
authors.lastname: Lanteri
authors.forename: Philip J
authors.initials: PJ
authors.lastname: Norris
authors.forename: Jason D
authors.initials: JD
authors.lastname: Barbour
authors.forename: Douglas J
authors.initials: DJ
authors.lastname: Wachter
authors.forename: Jan
authors.initials: J
authors.lastname: Andersson
authors.forename: Kjetil
authors.initials: K
authors.lastname: Taskén
authors.forename: Eirik A
authors.initials: EA
authors.lastname: Torheim
authors.forename: Einar M
authors.initials: EM
authors.lastname: Aandahl
authors.forename: Esper G
authors.initials: EG
authors.lastname: Kallas
authors.forename: Douglas F
authors.initials: DF
authors.lastname: Nixon
mesh_terms: D015703:Antigens, CD / Q000276:immunology*; D001081:Apyrase / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology / Q000276:immunology*; D049109:Cell Proliferation; D016207:Cytokines / Q000096:biosynthesis / Q000276:immunology; D006801:Humans; D016176:T-Lymphocyte Subsets / Q000166:cytology / Q000276:immunology*
chemical_list: D015703:Antigens, CD; D016207:Cytokines; D001081:Apyrase; C067869:CD39 antigen