目的： 探讨支气管上皮细胞与嗜酸性粒细胞联合培养过程中炎性介质的释放及其机制. 方法：应用流式细胞微珠实验(CBA)方法定量比较嗜酸性粒细胞、支气管上皮细胞及其联合培养上清液中单核细胞趋化蛋白(MCP)1的释放以及p38 MAPK抑制剂SB 203580干预的影响;
【关键词】支气管,上皮细胞,嗜酸细胞,单核细胞化学吸引蛋白质1,p38 MAPK
Regulatory role of p38 MAPK for MCP1 release from activated bronchial epithelial cells by eosinophils
【Abstract】 AIM: To investigate the release of monocyte chemoattractant protein (MCP)1 from the coculture of human bronchial epithelial cells and eosinophils and the related mechanisms. METHODS: MCP1 in culture supernatant was determined by Cytometric Bead Array (CBA) Kit in flow cytometry to compare MCP1 release in bronchial epithelial cells and eosinophils cultured alone or together, and investigate the inhibitive effect of SB 203580, a selective inhibitor of p38 MAPK, on MCP1 release. The reverse transcriptasepolymerase chain reaction (RTPCR) was used to analyze the gene expression of MCP1 in bronchial epithelial cells during coculture with eosinophils and the effect of SB 203580. RESULTS: The interaction of eosinophils and bronchial epithelial cells was found to upregulate the gene expression of MCP1 in epithelial cells. MCP1 in coculture supernatant of bronchial epithelial cells and eosinophils was elevated significantly [(1266±127) ng/L vs (134±25) ng/L,P<0.001]. Fixed eosinophils, which lost the ability to release MCP1, could also elevate epithelial cells to release MCP1 [(773±48) ng/L vs (107±15) ng/L, P<0.001] in coculture. SB 203580 could effectively inhibit MCP1 gene expression of bronchial epithelial cells during coculture with eosinophils, and decreased the release of MCP1 in the coculture of epithelial cells and eosinophils or fixed eosinophils [(1335±115) ng/L vs (481±42) ng/L, (868±89) ng/L vs (239±26) ng/L, P<0.001]. CONCLUSION: Eosinophils can activate bronchial epithelial cells to express MCP1 in coculture by p38 MAPK pathway so as to regulate the airway inflammatory reaction.
【Keywords】 bronchi; epithelial cells; eosinophils; monocyte chemoattractant protein1; p38 MAPK
【摘要】 用逆转录聚合酶链反应(RTPCR)分析联合培养过程中嗜酸性粒细胞对支气管上皮细胞MCP1基因表达的活化及SB 203580对MCP1表达的抑制作用. 结果： 经嗜酸性粒细胞活化后，支气管上皮细胞中MCP1基因表达明显上调;嗜酸性粒细胞和支气管上皮细胞联合培养上清液中MCP1蛋白质释放显著增加[(1266±127) ng/L vs (134±25) ng/L, P<0.001];多聚甲醛固定后的嗜酸性粒细胞不能释放MCP1，但其在与支气管上皮细胞联合培养过程中仍可增加支气管上皮细胞释放MCP1 [(773±48) ng/L vs (107±15) ng/L, P<0.001];p38 MAPK抑制剂SB 203580可有效抑制嗜酸性粒细胞活化支气管上皮细胞表达MCP1基因，显著降低正常嗜酸性粒细胞和多聚甲醛固定嗜酸性粒细胞与支气管上皮细胞联合培养过程中MCP1的释放[(1335±115) ng/L vs (481±42) ng/L和(868±89) ng/L vs (239±26) ng/L, P<0.001]. 结论： 嗜酸性粒细胞可通过p38 MAPK信号传导通路活化支气管上皮细胞表达MCP1，调控过敏性气道炎症反应.
0引言
过敏性哮喘的显著特点就是大量炎性细胞，特别是嗜酸性粒细胞在支气管炎症部位聚积，活化后的嗜酸性粒细胞可通过脱颗粒释放嗜酸性粒细胞阳性蛋白(ECP)、主要碱性蛋白(MBP)等毒性蛋白，而这些毒性蛋白可造成支气管上皮损伤[1]. 损伤的支气管上皮修复和气道重建可导致气道水肿、增厚、狭窄和对不同刺激的反应性增高，从而引发常见的咳嗽、呼吸困难等一系列临床症状. 支管上皮对外环境的屏障功能已被广泛认识，但作为哮喘炎症反应的发生部位，其在过敏性哮喘发生、发展中的免疫调控作用未能引起广泛重视. 我们通过嗜酸粒细胞与支气管上皮细胞接触培养为实验模型，探讨哮喘过程中嗜酸粒细胞从外周血移行至支气管上皮后，通过活化支气管上皮释放炎性介质细胞趋化因子MCP1，调控过敏性哮喘炎性反应的过程.
1材料和方法
1.1材料密度1.082 kg/L Percoll溶液: 混合87.92 mL Percoll原液(密度1.130, 瑞典Amersham公司产品)，15 mL 1.5 mol/L NaCl
