LAT alleviates Th2/Treg imbalance in an OVA-induced allergic asthma mouse model through LAT-PLC-γ1 interaction
LAT alleviates Th2/Treg imbalance in an OVA-induced allergic asthma mouse model through LAT-PLC-γ1 interaction
复制标题
LAT 通过 LAT-PLC-gamma 1 相互作用缓解 OVA 诱导的过敏性哮喘小鼠模型中 Th2/Treg 失衡
DOI：
10.1016/j.intimp.2016.12.029
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发表时间：
2017-03-01
影响因子：
5.6
通讯作者：
Guo, Xue-jun
中科院分区：
文献类型：
--
作者：
Chen, Xi;Li, Xiao-ming;Guo, Xue-jun
引言：在哮喘中观察到T细胞活化连接蛋白（LAT）表达较低。LAT及其下游调节因子磷脂酶Cγ1（PLC -γ1）在T细胞抗原受体信号通路中起重要作用，它们的相互作用与CD4⁺细胞极化有关。在此，我们研究了LAT是否能够缓解CD4⁺细胞亚群之间的失衡以及可能的机制。
方法：建立卵清蛋白诱导的过敏性哮喘小鼠模型并导入LAT质粒。通过苏木精 - 伊红染色和过碘酸 - 希夫染色评估肺的病理变化。采用酶联免疫吸附测定法测量辅助性T细胞2（Th2）和调节性T细胞（Treg）释放的典型细胞因子，利用流式细胞术确定Th1、Th2和Treg细胞的数量。通过磁分离法分离肺CD4⁺T细胞。通过实时定量聚合酶链反应测定LAT和PLC -γ1的mRNA表达。进行免疫共沉淀以确认LAT和PLC -γ1之间的相互作用。通过蛋白质印迹法测定LAT、PLCγ1以及相应下游信号因子的蛋白质表达。
结果：将LAT DNA导入肺可通过减少过敏反应和Th2细胞因子分泌以及增加Treg细胞因子分泌来抑制过度活跃的Th2反应。LAT DNA导入可纠正肺中Th2/Treg失衡以及肺CD4⁺T细胞中磷酸化PLC -γ1表达的降低。哮喘后Raf - MEK - ERK和PI3K - AKT - CREB通路的过度激活可被LAT减弱。
结论：将LAT DNA特异性导入肺可抑制哮喘小鼠模型中过度活跃的Th2反应并纠正Th2/Treg失衡。LAT - PLC -γ1相互作用可能有助于LAT在体内的活性，并且LAT部分通过Raf - MEK - ERK和PI3K - AKT - CREB通路预防哮喘。LAT DNA的导入可为哮喘预防提供一种新的安全策略。（C）2016爱思唯尔公司。保留所有权利。
Introduction: Low expression of linker for activation of T cells (LAT) is observed in asthma. LAT and its downstream regulator, phospholipase Cgamma 1 (PLC-gamma 1) play important roles in the T cell antigen receptor signaling pathway, and their interaction is associated with CD4(+) cell polarization. Here, we investigated whether LAT can alleviate the imbalance among CD4(+) cell subgroups and the possible mechanism.Methods: An ovalbumin-induced allergic asthma mouse model was established and LAT plasmid was delivered. The pathological changes in lung were evaluated by hematoxylin and eosin and periodic acidSchiff staining. The typical cytoldnes released by T helper 2 (Th2) and regulatory T (Treg) cells were measured using enzymelinked immunosorbent assay and the number of Thl, Th2, and Treg cells were determined using flow cytometry. Lung CD4(+) T cells were isolated by magnetic isolation. The mRNA expression of LAT and PLC-gamma l was determined by real-time PCR. Co-Immunoprecipitation was performed to confirm the interaction between LAT and PLC-gamma 1. The protein expression of LAT, PLC gamma 1 and corresponding downstream signaling factors were determined by western blotting.Results: The delivery of LAT DNA to the lung could suppress an overactive Th2 response by decreasing allergicsesponse and Th2 cytokine secretion, and by increasing Treg cytokine secretion. The Th2/Freg imbalance in lung and decreased phosphorylated PLC-gamma 1 expression in lung CD4(+) T cells were rectified by LAT DNA delivery. Excessive activation of the Raf-MEK-ERK and PI3K-AICT-CREB pathways after asthma is attenuated by LAT.Conclusion: The sitespecific delivery of EAT DNA to the lung could suppress an overactive Th2 response and rectify the Th2/Treg imbalance in asthmatic mouse model. LAT-PLC-gamma 1 interaction may contribute to LAT activity in vivo and LAT protects against asthma partly via Raf-MEK-ERK and PI3K-AKT-CREB pathways. The delivery of LAT DNA could offer a novel and safe strategy for asthma prevention. (C) 2016 Elsevier B.V. All rights reserved.