IL-33对双阴性T细胞的免疫调控作用及其在Con A诱导免疫性肝损伤中的应用研究

Immune cells play a key role in the development of liver injury. Immunotherapy based on immune cells and cytokines is a new therapeutic target in acute liver injure. We recently found that DNT cells were significantly increased and inhibited liver immune injury in Con A induced autoimmune hepatitis. Nevertheless, the origin of DNT cells is rare and in immune anergic state. Il-33 is a dual-direction regulation cytokine which can mediate tissue-protective functions during the recovery phase. We found that ST2, the receptor of IL-33, was expressed on DNT cells, and IL-33 stimulation could promote proliferation and inhibit apoptosis and ever augment the suppression function of DNT cells, but the mechanism was unclear. In this study, we aim to determine the effect of Il-33 on DNT cells proliferation, apoptosis and immune regulation function. Then, test the expression of Bcl-2, Bcl-xL, Survivin, Perforin with flow cytometry and qPCR. Next, explore the main molecular in the regulation and the function of MyD88-TRAF6-NF-κB signal with RNA interference or gene knockout methods. At last, identify the protection function combined DNT cells and IL-33 in Con A induced autoimmune hepatitis. This study will give support to its feasibility in application as a promising cell-based strategy for treatment of liver immune mediated injury.

免疫因素参与肝损伤的发生、发展，基于免疫调节细胞的免疫疗法可为急性肝损伤治疗提供新的靶点。DNT细胞可减轻ConA诱导的免疫性肝损伤，前期研究显示DNT细胞表达IL-33受体ST2，且IL-33可促进DNT细胞增殖，使其凋亡减少，并增强其免疫抑制功能，但作用机制尚不清楚。我们拟通过体外实验明确IL-33对DNT细胞增殖、凋亡及免疫抑制功能的影响；其次通过流式细胞仪及荧光定量PCR检测发挥作用效应分子Bcl-2、Bcl-xL、Survivin及Perforin等变化；再次采用RNA干扰、基因敲除等相关技术探讨IL-33调控DNT细胞作用的靶分子及MyD88-TRAF6-NF-κB信号通路的作用；最后通过ConA诱导免疫性肝损伤模型，观察联合应用DNT细胞和IL-33对急性肝损伤的预防及治疗作用。本研究将为急性肝损伤的免疫治疗提供新的方向及理论依据。

肝脏损伤如不能得到有效及时的治疗，重者可致肝衰竭，病死率高。同时慢性肝损伤肝脏内长期炎症反应可致肝纤维化、肝硬化、肝衰竭，并增加肝癌发生风险，给社会经济带来很大负担。早期有效控制肝脏炎症，减少肝细胞破坏对延缓肝损伤病程及减少并发症的发生发展有重要的意义。过继转移DNT细胞可减轻Con A引起的免疫性肝损伤，为急性肝损伤的治疗提供了新的思路。但DNT细胞同时存在来源少、远期治疗效果欠佳等问题，如何进一步优化DNT细胞功能具有重要的意义，是重要的科学问题。.我们前期基础发现DNT细胞表达细胞因子IL-33受体ST2，在此课题中，我们首先通过体内外实验明确IL-33对DNT细胞增殖、凋亡及免疫抑制功能的影响；其次进一步阐明了IL-33调控DNT细胞存活的靶点及其机制；最后通过建立Con A诱导免疫性肝损伤模型，观察联合应用DNT细胞和IL-33对急性肝损伤的治疗作用，进一步证实了IL-33对改善DNT细胞功能的优势。本研究聚焦DNT细胞对肝损伤的治疗，为优化DNT细胞的功能提供了重要的理论基础和依据，也为急性肝损伤的治疗提供了更优的免疫细胞治疗技术。.围绕DNT细胞及肝脏免疫，在国自然青年项目经费的资助下，以第一作者身份即将发表SCI论文1篇（Cell Death Dis，IF：9.685），核心期刊1篇（已经接收）。