酒精性肝炎中调节性NKT10细胞对NK细胞的过度负调及其病理机制

Immune mechanisms leading to liver injury following chronic alcohol ingestion are poorly understood. The over-activation of NKT cells and suppression of NK cells induced by chronic alcohol consumption contributes to the progression of alcoholic liver disease. But how interactions between NKT cells and NK cells wad still unknown. In our previous studies, the IL-10-production NKT subset (NKT10), which was a distinct regulatory invariant NKT cell, was increased in liver of alcohol fed mice. The aims of this project to verify whether the NKT10 cells to promote the progression of ALD by inhibition NK cell through IL-10. The characteristics of NKT10 cell including phenotypes, secretion of IL-10, distribution in liver tissue, and the correlation of NKT10 with the suppression of NK cell functions are studied. That NKT10 cells transfusion to NKT deficient mice to verify the regulation of NKT10 cells to NK cells. NK cell functions are recovered in IL-10 deficient mice or by blocking IL-10, which leading to ameliorate ALD. Data from cell interaction in vitro (co-incubated culture, soluble molecular detection, antibody blocking etc.) indicate the regulation of NKT10 cells on NK cells and the key role of IL-10.

酒精性肝炎免疫机制研究相对滞后并面临全球性挑战。最近分别发现自然杀伤T（NKT）细胞过度活化或NK细胞功能被抑制是导致酒精性肝病（ALD）发生发展的重要原因，誉为本领域二大重要进展，但二类细胞间是否存在内在联系仍然不明。我们预实验发现，酒精饲喂小鼠肝脏升高的iNKT细胞为分泌IL-10的调节性iNKT细胞亚群（NKT10亚群）。本课题拟验证NKT10细胞是否通过IL-10对NK细胞进行直接负调来促进ALD的发生，将系统观察酒精饲喂小鼠肝脏NKT10细胞表型特征、IL-10分泌、肝组织分布等特性，以及与NK细胞功能受抑的相关性；对NKT缺陷鼠回输NKT10细胞来验证对NK细胞的负调；观察IL-10缺陷鼠或IL-10抗体对NK细胞功能恢复和治疗ALD的作用；通过体外细胞互作（细胞共孵育、可溶性分子检测、抗体阻断等）阐明NKT10细胞对NK细胞的负调效应及IL-10的关键作用。

酒精性肝炎免疫机制研究相对滞后并面临全球性挑战。研究发现NKT细胞过度活化或NK细胞功能被抑制是导致酒精性肝病（ALD）发生发展的重要原因，但二类细胞间是否存在内在联系仍然不明。本课题拟验证NKT细胞通过对NK细胞的负调来促进ALD的发生。在chronic-binge酒精性肝损伤模型中，我们发现：1）肝脏NK细胞的比例与数目与NKT细胞呈负向变化；2）NK细胞可以通过分泌IFN-γ在ALD中发挥保护作用；3）NKT细胞通过分泌IL-10抑制NK细胞的数量和功能进而促进ALD的发生，阻断IL-10可以抑制ALD的发生。这些结果提示IL-10可能是ALD重要的干预靶点，为临床治疗ALD提供理论依据。