title: CD4+ T cell expressed CD80 regulates central nervous system effector function and survival during experimental autoimmune encephalomyelitis.
abstract: CD80 expressed on the surface of APCs provides a positive costimulatory signal to naive CD4+ T cells during activation. Therefore, it was hypothesized that treatment of SJL mice with various forms of anti-CD80 mAb during remission from the acute phase of relapsing experimental autoimmune encephalomyelitis (R-EAE) would ameliorate disease progression. We previously reported that treatment of SJL mice with anti-CD80 Fab during R-EAE remission blocked activation of T cells specific for endogenous myelin epitopes, inhibiting epitope spreading and clinical disease progression; however, treatment with the native form of the same anti-CD80 mAb exacerbated disease progression. The current data show that intact anti-CD80 mAb binds both CNS-infiltrating CD4+ T cells and CD11c+ dendritic cells and that exacerbation of R-EAE directly correlates with increased survival and activity of myelin-specific CD4+ T cells, while the percentage of CD11c+ dendritic cells in the CNS and their APC activity was not altered. In vitro data show that cross-linking CD80 on the surface of CD4+ T cells activated in the presence of Th1-promoting cytokines increases the level of T cell activation, effector function, and survival by directly up-regulating the expression levels of transcripts for T-bet, IFN-gamma, and Bcl-xL. These findings indicate a novel regulatory role for CD80-mediated intracellular signals in CD4+ T cells and have important implications for using anti-costimulatory molecule mAb therapy in established autoimmune disease.
authors.affiliation: Department of Microbiology-Immunology and Interdepartmental Immunobiology Center, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA.
authors.forename: Joseph R
authors.initials: JR
authors.lastname: Podojil
authors.forename: Adam P
authors.initials: AP
authors.lastname: Kohm
authors.forename: Stephen D
authors.initials: SD
authors.lastname: Miller
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D000938:Antigen-Presenting Cells / Q000276:immunology / Q000378:metabolism; D018122:B7-1 Antigen / Q000276:immunology* / Q000378:metabolism*; D039521:CD11c Antigen / Q000378:metabolism; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D002470:Cell Survival / Q000276:immunology; D002478:Cells, Cultured; D003713:Dendritic Cells / Q000276:immunology / Q000378:metabolism; D004681:Encephalomyelitis, Autoimmune, Experimental / Q000276:immunology* / Q000378:metabolism / Q000473:pathology*; D000939:Epitopes / Q000276:immunology; D005260:Female; D007371:Interferon-gamma / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology; D051379:Mice; D018991:Myelin Proteolipid Protein / Q000276:immunology / Q000494:pharmacology; D010446:Peptide Fragments / Q000276:immunology / Q000494:pharmacology; D020825:T-Box Domain Proteins; D014157:Transcription Factors / Q000235:genetics; D051020:bcl-X Protein / Q000235:genetics; D000098815:T-bet Transcription Factor
chemical_list: D000911:Antibodies, Monoclonal; D018122:B7-1 Antigen; D039521:CD11c Antigen; D000939:Epitopes; D018991:Myelin Proteolipid Protein; D010446:Peptide Fragments; D020825:T-Box Domain Proteins; D000098815:T-bet Transcription Factor; D014157:Transcription Factors; D051020:bcl-X Protein; D007371:Interferon-gamma