The Mas-related G protein–coupled receptor X2 (MRGPRX2) is a multiligand receptor responding to various exogenous and endogenous stimuli. Being highly expressed on skin mast cells, MRGPRX2 triggers their degranulation and release of proinflammatory mediators, and it promotes multicellular signaling cascades, such as itch induction and transmission in sensory neurons. The expression of MRGPRX2 by skin mast cells and the levels of the MRGPRX2 agonists (eg, substance P, major basic protein, eosinophil peroxidase) are upregulated in the serum and/or skin of patients with inflammatory and pruritic skin diseases, such as chronic spontaneous urticaria or atopic dermatitis. Therefore, MRGPRX2 and its agonists might be potential biomarkers for the progression of cutaneous inflammatory diseases and the response to treatment. In addition, they may represent promising targets for prevention and treatment of signs and symptoms in patients with skin diseases or drug reactions. To assess this possibility, this review explores the role and relevance of MRGPRX2 and its activators in cutaneous inflammatory disorders and chronic pruritus.

Mas 相关 G 蛋白偶联受体 X2 (MRGPRX2) 是一种多配体受体，可响应各种外源性和内源性刺激。在皮肤肥大细胞上高度表达，MRGPRX2 触发它们的脱颗粒和促炎介质的释放，并促进多细胞信号级联，例如感觉神经元中的瘙痒诱导和传递。皮肤肥大细胞对 MRGPRX2 的表达和 MRGPRX2 激动剂（例如 P 物质、主要碱性蛋白、嗜酸性粒细胞过氧化物酶）的水平在患有炎症和瘙痒性皮肤病（例如慢性自发性皮肤病）的患者的血清和/或皮肤中上调荨麻疹或特应性皮炎。因此，MRGPRX2及其激动剂可能是皮肤炎症性疾病进展和治疗反应的潜在生物标志物。此外，它们可能是预防和治疗皮肤病或药物反应患者的体征和症状的有希望的目标。为了评估这种可能性，本综述探讨了 MRGPRX2 及其激活剂在皮肤炎症性疾病和慢性瘙痒中的作用和相关性。