Roxithromycin (ROX) is a macrolide antibiotic with a variety of immunological effects. Mast cells (MCs) play a key role in host defense, mediating hypersensitivity and pseudo-allergic reactions. Mas-related G protein-coupled receptor X2 (MrgprX2) is the main receptor related to pseudo-allergy. In this study, we investigated the anti-pseudo-allergy effect of ROX and its underlying mechanism. The effects of ROX on passive cutaneous anaphylaxis (PCA) and active systemic allergy were examined, degranulation, Ca²⁺ influx, and cytokine release were studied in vivo and in vitro. Interactions between ROX and MrgprX2 protein were also detected through surface plasmon resonance. The PCA and active systemic allergy induced by compound 48/80 were inhibited by ROX. An intermolecular interaction was detected between the ROX and MrgprX2 protein. In conclusion, ROX could inhibit pseudo-allergic reactions, and this effect involves the Ca²⁺/PLC/IP3 pathway of MrgprX2. This study provides new insight into the anti-pseudo-allergy effects of ROX.

罗红霉素（ROX）是一种大环内酯类抗生素，具有多种免疫作用。肥大细胞（MCs）在宿主防御，介导超敏反应和伪过敏反应中起关键作用。Mas相关的G蛋白偶联受体X2（MrgprX2）是与拟变态反应相关的主要受体。在这项研究中，我们研究了ROX的抗伪过敏作用及其潜在机制。研究了ROX对被动性皮肤过敏反应（PCA）和主动性全身过敏的影响，并在体内和体外研究了脱颗粒，Ca ^2+内流和细胞因子释放。ROX和MrgprX2蛋白之间的相互作用也通过表面等离子体共振检测。化合物48/80诱导的PCA和活性全身过敏被ROX抑制。检测到ROX和MrgprX2蛋白之间的分子间相互作用。总之，ROX可以抑制假性过敏反应，这种作用涉及MrgprX2的Ca ²⁺ / PLC / IP3途径。这项研究为ROX的抗伪过敏效应提供了新的见解。