1017 MRGPRX2-mediated mast cells activation regulates neutrephil infiltration in the early inflammatory reaction of psoriasis

Psoriasis is a chronic and recurrent inflammatory disease. Adaptive immunity plays an important role in psoriasis. Recent studies have confirmed that innate immune also necessary for psoriasis pathogenesis. The number of mast cells (MCs) has been reported to be significantly increased psoriatic lesions, which significant activation. However, the mechanism function MC activation not thoroughly reported. Whether MAS-related G protein-coupled receptor X2 (MRGPRX2), directly mediates many disease, associated with early reaction elucidated. To determine correlation between MRGPRX2 reaction, we marked MCs via immunohistochemistry immunofluorescence staining analyzed tumor necrosis factor (TNF)-α/interleukin (IL)-123/IL-17 axis. knock-in (MRGPRX2+/+) Mrgprb2 knockout (Mrgprb2-/-) mice were used as imiquimod (IMQ) model analyze neutrophil infiltration Finally, conditioned culture was show effect on results showed expression correlated levels TNF-α IL-17. MRGPRX2-mediated occurred stage IMQ mouse model, whereas Mrgprb2-/- reduced cytokine release, inflammation, infiltration. Furthermore, application tryptase, mediated by aggravated skin lesions inflammation model. induced chemotaxis tryptase chemokines release vitro. Our study clarified key regulatory reactions lesions.