急性肺损伤时HMGB1调控iPS和中性粒细胞竞争性组织归巢的作用及机制研究

Neutrophil infiltration is one of the key events of acute lung injury. Our previous research confirmed that the high mobility group protein (HMGB1) in the regulation of neutrophils (PMN) play an important role in tissue infiltration; induced pluripotent stem (iPS) cells transplantion ameliorate ischemia-reperfusion injury of lung by inhibiting PMN infiltration. Furthermore, studies have shown that integrin α4β1 is the important molecular for PMN ahesion with endothelial cell.Interesting, our newly researches revealed that the protection has been inhibited in the injuried tissue by downregulated the expression of integrin α4β1. Thus, we hypothesis that HMGB1 regulation of iPS and PMN competitive with homing and infiltration in injuried tissue. Through lung ischemia-reperfusion induced acute lung injury after neutrophil depletion and microfluid chip model, using the technology of transgenic and RNAi, to demonstrate that HMGB1 regulate the iPS,PMN competitive homing and infiltration in the lung tissue.In depth to investigate the role of integrin α4β1 mediated HMGB1 regulation of iPS,PMN competitive homing and infiltration in the injured lung tissue. This study is to provide a potential new means for improving the effectiveness of iPS targeted therapy.

中性粒细胞（PMN）的浸润是急性肺损伤的关键事件之一。我们证实高迁移率族蛋白（HMGB1）在调控PMN的组织浸润中起到重要作用；诱导性多能干细胞（iPS）治疗可缓解PMN浸润，减轻急性肺损伤。研究表明整合素α4β1是介导PMN与内皮细胞粘附的重要分子之一。我们最新发现抑制iPS整合素α4β1的表达，显著降低了iPS在多种损伤组织中的归巢。据此假设HMGB1可调控PMN与iPS的竞争性组织浸润和归巢。本项目拟通过左侧肺缺血再灌注损伤，结合外周血PMN去除和回输，利用微流控芯片、转基因及RNA干扰等技术，明确HMGB1对iPS和PMN在肺组织竞争性浸润和归巢的调控；进而检测HMGB1中和抗体存在的条件下，PMN和过表达整合素α4β1的iPS，以及在HMGB1刺激时，PMN和抑制整合素α4β1的iPS在细胞水平和肺损伤模型中的竞争性归巢作用，为提高iPS治疗效果提供潜在的新手段。

本项目研究内容①HMGB1调控iPS、PMN竞争性组织归巢和浸润，保护损伤肺组织的作用，同时静脉移植诱导性多能干细胞（iPSC）可在损伤肺组织中定向归巢和浸润，并不形成畸胎瘤；② 整合素α4β1在HMGB1调控iPS、PMN竞争性与血管内皮细胞粘附、跨内皮细胞迁移的作用。.取得的主要进展包括：① PMN在损伤肺组织中的归巢受到移植iPSC的干扰；②iPS与PMN在1:1，1:5的比例显著减轻肺缺血再灌注诱导肺功能损害、肺血管通透性、肺泡通透性和肺组织病理改变。而1:9的比例则抑制iPSC的定向归巢，从而干扰其靶向治疗效果； ③ 静脉移植整合素α4敲除的iPS未能改善缺血再灌注引起的PMN浸润、肺功能和病理改变；④ HMGB1介导iPS和PMN与血管内皮细胞的粘附、迁移和跨内皮细胞浸润，伴有整合素α4高表达，而HMGB1对整合素α4敲除的iPS生物学功能无影响。⑤ iPS与PMN 1:1，1:5的比例抑制PMN的粘附、迁移和跨内皮细胞浸润。.因此，通过调控iPS与PMN的比例，从而强化iPS的治疗效果，可有效减少PMN浸润导致组织损伤和缩短机体缺乏PMN保护的空窗期。.目前，已培养研究生4名，其中已毕业1名。总结论文9篇，已在Theranostics, Toxicol Lett，Bioorg Med Chem, Immunol Lett发表SCI论文5篇，其中第一作者和通讯作者4篇（一区1篇IF=8.75；1篇2区，2篇3区）；2篇论文已修回（Ebiomedicine IF=6.8，J molecular medicine IF=4.99）；其他数据已经整理并撰写成文待发表2篇。