title: Characterization of peripheral regulatory CD4+ T cells that prevent diabetes onset in nonobese diabetic mice.
abstract: The period that precedes onset of insulin-dependent diabetes mellitus corresponds to an active dynamic state in which pathogenic autoreactive T cells are kept from destroying beta cells by regulatory T cells. In prediabetic nonobese diabetic (NOD) mice, CD4+ splenocytes were shown to prevent diabetes transfer in immunodeficient NOD recipients. We now demonstrate that regulatory splenocytes belong to the CD4+ CD62Lhigh T cell subset that comprises a vast majority of naive cells producing low levels of IL-2 and IFN-gamma and no IL-4 and IL-10 upon in vitro stimulation. Consistently, the inhibition of diabetes transfer was not mediated by IL-4 and IL-10. Regulatory cells homed to the pancreas and modified the migration of diabetogenic to the islets, which resulted in a decreased insulitis severity. The efficiency of CD62L+ T cells was dose dependent, independent of sex and disease prevalence. Protection mechanisms did not involve the CD62L molecule, an observation that may relate to the fact that CD4+ CD62Lhigh lymph node cells were less potent than their splenic counterparts. Regulatory T cells were detectable after weaning and persist until disease onset, sustaining the notion that diabetes is a late and abrupt event. Thus, the CD62L molecule appears as a unique marker that can discriminate diabetogenic (previously shown to be CD62L-) from regulatory T cells. The phenotypic and functional characteristics of protective CD4+ CD62L+ cells suggest they are different from Th2-, Tr1-, and NK T-type cells, reported to be implicated in the control of diabetes in NOD mice, and may represent a new immunoregulatory population.
authors.affiliation: Centre National de la Recherche Scientifique, Unité Mixte de Recherche 8603, Université Paris V, Hôpital Necker, Paris, France. lepault@necker.fr
authors.forename: F
authors.initials: F
authors.lastname: Lepault
authors.forename: M C
authors.initials: MC
authors.lastname: Gagnerault
mesh_terms: D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D002454:Cell Differentiation / Q000276:immunology; D002465:Cell Movement / Q000276:immunology; D016207:Cytokines / Q000096:biosynthesis; D003922:Diabetes Mellitus, Type 1 / Q000209:etiology / Q000276:immunology* / Q000473:pathology / Q000517:prevention & control*; D005260:Female; D016130:Immunophenotyping; D007515:Islets of Langerhans / Q000276:immunology / Q000473:pathology; D007694:Killer Cells, Natural / Q000276:immunology; D019041:L-Selectin / Q000096:biosynthesis / Q000502:physiology; D008297:Male; D051379:Mice; D016688:Mice, Inbred NOD; D016513:Mice, SCID; D013154:Spleen / Q000276:immunology / Q000473:pathology; D016176:T-Lymphocyte Subsets / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D018418:Th2 Cells / Q000276:immunology
chemical_list: D016207:Cytokines; D019041:L-Selectin