title: MC5r and A2Ar Deficiencies During Experimental Autoimmune Uveitis Identifies Distinct T cell Polarization Programs and a Biphasic Regulatory Response.
abstract: Autoantigen-specific regulatory immunity emerges in the spleen of mice recovering from experimental autoimmune uveitis (EAU), a murine model for human autoimmune uveoretinitis. This regulatory immunity provides induced tolerance to ocular autoantigen, and requires melanocortin 5 receptor (MC5r) expression on antigen presenting cells with adenosine 2 A receptor (A2Ar) expression on T cells. During EAU it is not well understood what roles MC5r and A2Ar have on promoting regulatory immunity. Cytokine profile analysis during EAU revealed MC5r and A2Ar each mediate distinct T cell responses, and are responsible for a functional regulatory immune response in the spleen. A2Ar stimulation at EAU onset did not augment this regulatory response, nor bypass the MC5r requirement to induce regulatory immunity. The importance of this pathway in human autoimmune uveitis was assayed. PBMC from uveitis patients were assayed for MC5r expression on monocytes and A2Ar on T cells, and comparison between uveitis patients and healthy controls had no significant difference. The importance for MC5r and A2Ar expression in EAU to promote the induction of protective regulatory immunity, and the expression of MC5r and A2Ar on human immune cells, suggests that it may be possible to utilize the melanocortin-adenosinergic pathways to induce protective immunity in uveitic patients.
authors.affiliation: Department of Ophthalmology/Dean McGee Eye Institute, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA.
authors.forename: Darren J
authors.initials: DJ
authors.lastname: Lee
authors.affiliation: Massachusetts Eye Research and Surgery Institute, Waltham, Massachusetts, USA.|Ocular Immunology and Uveitis Foundation, Waltham, Massachusetts, USA.
authors.forename: Janine
authors.initials: J
authors.lastname: Preble
authors.affiliation: Massachusetts Eye Research and Surgery Institute, Waltham, Massachusetts, USA.|Ocular Immunology and Uveitis Foundation, Waltham, Massachusetts, USA.
authors.forename: Stacey
authors.initials: S
authors.lastname: Lee
authors.affiliation: Massachusetts Eye Research and Surgery Institute, Waltham, Massachusetts, USA.|Ocular Immunology and Uveitis Foundation, Waltham, Massachusetts, USA.|Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: C Stephen
authors.initials: CS
authors.lastname: Foster
authors.affiliation: Department of Ophthalmology, Boston University School of Medicine, Boston, Massachusetts, USA.
authors.forename: Andrew W
authors.initials: AW
authors.lastname: Taylor
mesh_terms: D000818:Animals; D001327:Autoimmune Diseases / Q000097:blood / Q000276:immunology*; D016022:Case-Control Studies; D016764:Cell Polarity / Q000235:genetics*; D016207:Cytokines / Q000378:metabolism; D006801:Humans; D051379:Mice; D008810:Mice, Inbred C57BL; D043683:Receptors, Adenosine A2 / Q000235:genetics*; D044101:Receptors, Melanocortin / Q000235:genetics*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*; D014605:Uveitis / Q000097:blood / Q000276:immunology*
chemical_list: D016207:Cytokines; D043683:Receptors, Adenosine A2; D044101:Receptors, Melanocortin; C086971:melanocortin 5 receptor