屋尘螨变应原对人肥大细胞脱颗粒的影响

目的：阐明屋尘螨变应原Derp1对人肥大细胞HMC-1释放类胰蛋白酶水平的影响。方法：流式细胞法测定HMC-1细胞表面蛋白酶激活受体2（PAR2）表达水平；将Derp1、SLIGRL-NH2（PAR2激活剂）、LRGILS-NH2（PAR2对照肽）及Derp1+ FSLLY（ PAR2拮抗剂）分别处理HMC-1细胞，用ELISA检测药物刺激后类胰蛋白酶水平；采用钙绿实验检测PAR2生物学功能。结果：肥大细胞表面表达PAR2受体；Derp1单独作用于HMC-1可明显引起HMC-1细胞内钙流释放及类胰蛋白酶的释放，类胰蛋白酶释放水平明显高于SLIGRL-NH2及正常对照；将Derp1与FSLLY共同作用于HMC-1时，可部分抑制HMC-1细胞内的钙流释放及类胰蛋白酶的释放。结论：屋尘螨变应原Derp1可以通过激活人肥大细胞HMC-1表面PAR2受体引起肥大细胞脱颗粒释放类胰蛋白酶。

Effect of house duct mite on the degranulation of the mast cells

Objective:To study the effects of the house dust mite allergen Derp1 on the secretion of tryptase from the human mast cell line HMC-1. Methods: Flow cytometry assay was performed to determine the expression levels of protease activated receptor 2 (PAR2) on the surface of HMC-1 cells. HMC-1 cells were treated with Derp1, SLIGRL-NH2 (PAR2 agonist), LRGILS-NH2 (control peptide for PAR2) or Derp 1 + FSLLY (PAR2 antagonist), respectively, then the tryptase levels were measured using enzyme-linked immunosorbent assay (ELISA). Biological functions of PAR2 were determined using the calcium green indicator. Results:PAR2 receptor was expressed on the surfaces of mast cells. Derp1 alone induced a signiifcant release of intracellular calcium and tryptase in HMC-1 cells. The level of tryptase release was signiifcantly higher compared with the SLIGRL-NH2 treatment group and the normal control group. The combination of Derp1 with FSLLY could partly inhibit intracellular calcium and tryptase release in HMC-1 cells.Conclusion:Derp1 can induce HMC-1 cells degranulation to release tryptase by activating the PAR2 receptor on the cell surface.