亮肽素、TLCK和乳铁蛋白对人结肠肥大细胞类胰蛋白酶释放的影响

目的：探讨亮肽素、N-甲苯磺酰-L-赖氨酸氯甲基化酮（TLCK）和乳铁蛋白对人结肠肥大细胞释放类胰蛋白酶的影响。 方法： 人结肠组织经酶消化后，细胞成份用全HBSS重新悬浮。激发过程在LP4试管中、37 ℃ 条件下完成。类胰蛋白酶水平用酶联免疫吸附试验（ELISA）方法测定。 结果： 亮肽素、TLCK和乳铁蛋白无明显刺激人结肠肥大细胞释放类胰蛋白酶的作用。但可以剂量依赖性的方式抑制抗IgE抗体诱导的类胰蛋白酶释放，抑制范围在36.6%-47.6%。在37 ℃条件下同结肠细胞预培养20 min与无预培养相比，亮肽素和TLCK对抗IgE抗体诱导的类胰蛋白酶释放的抑制作用无明显改变。亮肽素、TLCK和乳铁蛋白均可以抑制CI诱导的类胰蛋白酶释放，抑制范围在27.1%-44.1%。在37 ℃条件下同结肠细胞预培养20 min与无预培养相比，亮肽素对CI诱导的类胰蛋白酶释放的抑制作用明显增强，TLCK则无此特点。 结论： 我们首次发现类胰蛋白酶抑制剂可抑制人结肠肥大细胞IgE依赖性和非依赖性类胰蛋白酶释放，提示类胰蛋白酶抑制剂可治疗炎症性肠病或其它肥大细胞相关疾病。

Effect of leupeptin, TLCK and lactoferrin on tryptase release from human colon mast cells

AIM: To investigate the ability of leupeptin, TLCK and lactoferrin on tryptase release from human colon mast cells. METHODS: Human mast cells were dispersed from colon tissue with collagenase and hyaluronidase, and were challenged with stimulus for 15 min at 37 ℃. Tryptase concentrations were measured with a sandwich ELISA procedure. RESULTS: Leupeptin, TLCK and lactoferrin were not able to provoke significant tryptase release from human colon mast cells. But they were able to inhibit anti-IgE and calcium ionophore (CI)-induced tryptase release in a concentration-dependent manner. Preincubation of inhibitors of leupeptin and TLCK with cells for 20 min before challenging with anti-IgE failed to enhance their inhibitory actions. The extent of inhibition by leupeptin was increased when colon mast cells were preincubated for 20 min before CI being added. However, the same treatment failed to improve the action of TLCK. CONCLUSION: We found for the first time that leupeptin, TLCK and lactoferrin were able to inhibit anti-IgE and calcium ionophore-induced tryptase release from human colon mast cells, which may indicate a potential of a novel therapy for the treatment of inflammatory bowel disease or other mast cells-related diseases.