美洲大蠊过敏原Per a 7表达鉴定及其对Th17类细胞因子表达的影响

Identification of American cockroach allergen Per a 7 and its effect on expressions of Th17 cells-related cytokines

目的鉴定美洲大蠊过敏原Per a 7表达,研究其对辅助性T细胞17(Th17细胞)相关基因和蛋白表达的影响。方法用含编码Per a 7基因的大肠杆菌诱导表达并纯化出Per a 7蛋白。将磁珠分离后CD4+T淋巴细胞与Per a 7激发活化的树突状细胞共培养。采用实时荧光定量PCR检测IL-17、RORγt和Foxp3mRNA表达,ELISA检测上清液中IL-17含量。结果成功克隆分子量约为33kD的重组蛋白Per a 7。重组Per a 7激发后树突状细胞与CD4+T淋巴细胞共培养后,IL-17、RORγt mRNA表达以及上清液中IL-17含量增加(P<0.05),而Foxp3mRNA表达无明显变化(P>0.05)。结论美洲大蠊过敏原Per a 7能激发树突状细胞诱导T淋巴细胞向Th17细胞方向分化,在过敏性疾病发生中起了重要的作用。

Objective To identify the expression of American cockroach allergen Per a 7 and investigate its effect on the expressions of Th17 cells-related gene and protein .Methods Per a 7 protein was induced by Origami stain encoding Per a 7 gene ,and highly purified by affinity chromatography .Then CD4＋ T lymphocytes were co-cultured with Per a 7-activated dendritic cells . The mRNA expressions of IL-17 ,RORγt and Foxp3 were detected by RT-PCR ,and content of IL-17 in the supernatant was determined by ELISA .Results The recombinant Per a 7 with the molecular weight of 33 kD was successfully cloned .The mRNA expressions of IL-17 ,RORγt and content of IL-17 in the supernatant were increased after Per a 7-activated dendritic cells were co-cultured with CD4＋ T lymphocytes（P〈0 .05） ,while the mRNA expression of Foxp3 was not obviously changed （P〉0 .05） .Conclusion Per a 7 plays an important role in the development of allergic diseases probably through dendritic cells-induced Th17 polarization of CD4＋ T lymphocytes .