Abstract
Purpose:
To determine whether exosomes isolated from the sera of EAU mice contain uveitogenic interphotoreceptor petinoid binding protein (IRBP), and whether these IRBP-containing exosomes are immunogenic or tolerogenic.
Methods:
EAU was induced in C57BL/6 (B6) mice by immunization with IRBP1-20 peptides emulsified with complete Freund’s adjuvant. Exosomes were extracted from the sera of naïve and diseased mice by ultra-speed centrifuge. The presence of IRBP in the exosomes was examined by western blot using anti-IRBP Ab. IRBP-specific T cell responses after incubation with IRBP containing exosomes were tested by T cell proliferation assay. The severity of EAU treated with or without IRBP-containing exosomes was evaluated by histology.
Results:
Exosomes from the sera of EAU mice expressed significantly high level of IRBP compared to those from naïve mice. These IRBP containing exosomes inhibited the proliferation of uveitogenic T cells in vitro and suppressed the uveitis induced by IRBP-specific T cells in vivo.
Conclusions:
IRBP-containing exosomes was detected in the peripheral blood, which might deliver immunosuppressive signals to autoimmune T cells and might be used as a novel therapy for autoimmune uveitis.
Keywords: 432 autoimmune disease •
745 uvea •
555 immunomodulation/immunoregulation