Wang Haiyan, Yi Tingting, Zheng Yanshan, He Shaoheng
Allergy and Inflammation Research Institute, The Key Immunopharmacology Laboratory of Guangdong Province, Shantou University Medical College, Shantou 515041, China.
Eur J Cell Biol. 2007 Apr;86(4):233-42. doi: 10.1016/j.ejcb.2006.12.003. Epub 2007 Feb 5.
Hypersecretion of cytokines and serine proteases has been observed in asthma. However, the influence of proteases and protease-activated receptors (PARs) on monocyte chemoattractant protein-1 (MCP-1) release from airway epithelial cells remains largely unknown. In the present study, A549 cells were challenged with agonists of PARs, and levels of MCP-1 released in the supernatant and mRNA expression were examined by ELISA and real time polymerase chain reaction (PCR), respectively. The results show that thrombin, tryptase, elastase and trypsin induced an up to 6.5-, 1.8-, 1.6-, and 3.1-fold increase in MCP-1 release from A549 cells, respectively, following a 16-h incubation period. The protease-induced secretion of MCP-1 can be abolished by specific protease inhibitors. Agonist peptides of PAR-1 and PAR-2 stimulate MCP-1 secretion up to 15- and 12.7-fold, respectively. Real-time PCR showed that MCP-1 mRNA is up-regulated by the serine proteases tested and by agonist peptides of PAR-1 and PAR-2. In conclusion, serine proteases can stimulate MCP-1 release from A549 cells possibly through a PARs-related mechanism, suggesting that they are likely to contribute to MCP-1-related airway inflammatory disorders in man.
在哮喘中已观察到细胞因子和丝氨酸蛋白酶的分泌过多。然而，蛋白酶和蛋白酶激活受体（PARs）对气道上皮细胞释放单核细胞趋化蛋白-1（MCP-1）的影响在很大程度上仍不清楚。在本研究中，用PARs激动剂刺激A549细胞，分别通过酶联免疫吸附测定（ELISA）和实时聚合酶链反应（PCR）检测上清液中释放的MCP-1水平和mRNA表达。结果显示，在16小时的孵育期后，凝血酶、类胰蛋白酶、弹性蛋白酶和胰蛋白酶分别使A549细胞释放的MCP-1增加了6.5倍、1.8倍、1.6倍和3.1倍。蛋白酶诱导的MCP-1分泌可被特异性蛋白酶抑制剂消除。PAR-1和PAR-2的激动剂肽分别刺激MCP-1分泌达15倍和12.7倍。实时PCR显示，所测试的丝氨酸蛋白酶以及PAR-1和PAR-2的激动剂肽可上调MCP-1 mRNA。总之，丝氨酸蛋白酶可能通过与PARs相关的机制刺激A549细胞释放MCP-1，这表明它们可能在人类MCP-1相关的气道炎症性疾病中发挥作用。
