Abstract: Objective To explore the anti-infective mechanism of carboxyamidotriazole (CAI) through studying the effects of CAI on the proliferation, apoptosis and degranulation of RBL-2H3 mass cells. Methods Compound 48/80 (C48/80) was used to induce the model of activation and degranulation in RBL-2H3 cells. The morphological change of cell degranulation was observed by neutral red staining. The release levels of histamine and β-hexosaminidase were measured by ELISA method and chromogenic assay, respectively. The cell activity was determined by CCK-8 method. And cell apoptosis was detected by Hoechst 33342 fluorescent staining. Results Compared with the control group, 10, 20, 40 mol/L CAI inhibited C48/80-induced degranulation of RBL-2H3 cells in different degrees. CAI (20, 40 mol/L) reduced the histamine release (P<0.01), and CAI (40 mol/L) decreased the β-hexosaminidase release (P<0.01). In addition, the viability and apoptosis of RBL-2H3 cells were not affected at the concentrations of CAI used. Conclusions CAI can effectively inhibit the activation and degranulation of RBL-2H3 mast cells, and this effect is not through cytotoxicity. The anti-infection effect of CAI may partially due to the down-regulation of mast cell activity.

Key words: Keywords carboxyamidotriazole, RBL-2H3 cells, C48/80, degranulation