Psoriasis is a chronic inflammatory skin disease. IL-23 plays a critical role in its pathogenesis by inducing production of IL-17A from pathological Th17 cells and IL-17A–producing γδ T cells. However, the mechanisms regulating the IL-23/IL-17 axis in psoriasis are incompletely understood. In this study, we show that, in comparison with wild-type mice, those deficient in the CD96 immunoreceptor had lower production of IL-17A in their dermal γδ T cells and milder psoriasis-like dermatitis after topical application of imiquimod (IMQ). Moreover, transfer of CD96-deficient dermal γδ T cells into the skin of Rag1-deficient mice resulted in them developing milder IMQ-induced dermatitis compared with Rag1-deficient mice transferred with wild-type dermal γδ T cells. In γδ T cells in vitro, CD96 provides a costimulatory signal for the production of IL-23–induced IL-17A. In mice given an anti-CD96 neutralizing Ab, IL-17A production from dermal γδ T cells decreased and IMQ-induced dermatitis was milder compared with mice given a control Ab. These results suggest that CD96 is a potential molecular target for the treatment of psoriasis.
This work was supported by Ministry of Education, Culture, Sports, Science, and Technology of Japan Grants 16H06387 (to A.S.), 21H02708 and 21K19369 (to K.S.), and 21K06943 (to K.O.), Japan Agency for Medical Research and Development Grant A19-39 (to K.S.), and by Japan Society for the Promotion of Science Grant-in-Aid 20J40217 (to K.O.). The sponsors had no control over the interpretation, writing, or publication of this work.
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