title: Mechanisms of PDL1-mediated regulation of autoimmune diabetes.
abstract: The PD-1-PDL1 pathway plays a critical role in regulating autoimmune diabetes as blockade or deficiency of PD-1 or PDL1 results in accelerated disease in NOD mice. We explored the cellular mechanisms involved in the regulation of these autoimmune responses by investigations involving various gene-deficient mice on the NOD background. Administration of blocking anti-PDL1 antibody to CD4+ T cell-deficient, CD8+ T cell-deficient and B cell-deficient mice demonstrated that PDL1-mediated regulation of autoreactive CD4+ and CD8+ T cells is critical for diabetes development. This concept was confirmed by adoptive transfer studies utilizing lymphocytes from BDC2.5 and 4.1 (CD4+) TCR transgenic mice and 8.3 (CD8+) TCR transgenic mice; efforts showing increased proliferation of both CD4+ and CD8+ T cells following PDL1 blockade in vivo. Furthermore, we observed that anti-PDL1-mediated acceleration is dependent upon events occurring in the pancreatic lymph nodes during early disease stages, but becomes independent of the pancreatic lymph nodes during later disease stages. These data provide strong evidence that PDL1 regulates autoimmune diabetes by limiting the expansion of CD4+ and CD8+ autoreactive T cells, and define the timing and locale of PDL1-mediated regulation of type 1 diabetes.
authors.affiliation: Transplantation Research Center, Brigham and Women's Hospital and Children's Hospital Boston, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Indira
authors.initials: I
authors.lastname: Guleria
authors.forename: Melanie
authors.initials: M
authors.lastname: Gubbels Bupp
authors.forename: Shirine
authors.initials: S
authors.lastname: Dada
authors.forename: Brian
authors.initials: B
authors.lastname: Fife
authors.forename: Qizhi
authors.initials: Q
authors.lastname: Tang
authors.forename: Mohammed Javeed
authors.initials: MJ
authors.lastname: Ansari
authors.forename: Subbulaxmi
authors.initials: S
authors.lastname: Trikudanathan
authors.forename: Nidyanandh
authors.initials: N
authors.lastname: Vadivel
authors.forename: Paolo
authors.initials: P
authors.lastname: Fiorina
authors.forename: Hideo
authors.initials: H
authors.lastname: Yagita
authors.forename: Miyuki
authors.initials: M
authors.lastname: Azuma
authors.forename: Mark
authors.initials: M
authors.lastname: Atkinson
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Bluestone
authors.forename: Mohamed H
authors.initials: MH
authors.lastname: Sayegh
mesh_terms: D019264:Adoptive Transfer; D000818:Animals; D015551:Autoimmunity; D018122:B7-1 Antigen / Q000276:immunology*; D060890:B7-H1 Antigen; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D003922:Diabetes Mellitus, Type 1 / Q000276:immunology* / Q000503:physiopathology*; D005260:Female; D005434:Flow Cytometry; D008562:Membrane Glycoproteins / Q000276:immunology*; D051379:Mice; D016688:Mice, Inbred NOD; D008822:Mice, Transgenic; D010455:Peptides / Q000276:immunology*
chemical_list: D018122:B7-1 Antigen; D060890:B7-H1 Antigen; C498919:Cd274 protein, mouse; D008562:Membrane Glycoproteins; D010455:Peptides