Anti-Inflammatory Role of IL-17 in Experimental Autoimmune Uveitis

Department of Ophthalmology and Visual Sciences, Kentucky Lions Eye Center, University of Louisville, KY 40202, USA.
The Journal of Immunology (Impact Factor: 5.36). 04/2009; 182(5):3183-90. DOI: 10.4049/jimmunol.0802487
Source: PubMed

ABSTRACT Previous studies have shown that IL-17 is a strong proinflammatory cytokine and that IL-17-producing autoreactive T cells play a major role in the pathogenesis of autoimmune diseases. In a previous study, we showed that injection of experimental autoimmune uveitis-susceptible mice with anti-IL-17 Abs blocked subsequent disease development. To determine whether administration of IL-17 to experimental autoimmune uveitis-susceptible Lewis rats and B10RIII mice injected with disease-inducing peptides enhanced disease susceptibility, we injected the recipient animals with various doses of human rIL-17 (hIL-17). Unexpectedly, the treated animals showed significant amelioration of disease; in addition, both the intensity of the autoreactive response and cytokine production by the autoreactive T cells induced by immunization with uveitogenic peptides were significantly decreased. Our results show that IL-17 has anti-inflammatory activity and that this cytokine can suppress the development of autoimmune disease.

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