调节性T细胞缺陷在NTG患者HSP介导的自身免疫相关视神经节细胞丢失中的作用机制

Progressive retinal ganglion cell (RGC) loss are observed in the normal tension glaucoma (NTG) patients whose intraocular pressure (IOP) fluctuate within the normal range. This phenomenon suggests other factors than IOP may play an important role in the progression of glaucoma. Obvious activation of heat-shock protein (HSP) specific immune responses in glaucoma patients was reported in many studies. Meanwhile, glaucomatous RGC loss was also observed in HSP60 related immune response animal model. In our previous studies, we found that serum HSP60 antibody titer elevated in NTG patients. And we found the imbalance of pro-and anti-inflammatory factors in normal tension glaucoma patients after exposed to HSP60 antigen. In this study, to assess the role of regulatory T cells deficiency in HSP induced autoimmune destruction in RGC, the association between actual pathogenesis and immune response will be evaluated via analysis of peripheral blood samples of NTG patients. HSP60 abdominal immune animal model will be built to simulate the possible role of HSP60 in RGC injury. The count, function and infiltration of regulatory T cells and Th2 will be observed to explore the immune factor to RGC deficiency in NTG patients. Moreover, we will delete Treg cells in rat models to simulate the role of regulatory T cells defect in RGC damage in NTG patients and manipulate upper-stream malt 1 gene to investigate possible related pathological mechanism to RGC injury. The study on regulatory T cells may bring a new way for NTG therapy.

正常眼压性青光眼（NTG）眼压正常仍有视网膜神经节细胞（RGC）凋亡，说明有其他因素在其发病中起重要作用。研究显示青光眼患者体内存在明显的热休克蛋白（HSP）相关免疫反应，HSP60腹腔免疫模型中有与青光眼相似的RGC丢失。我们发现NTG患者的外周血中HSP60抗体增加、HSP60刺激后发挥抑炎作用的调节性T细胞（Treg）与发挥促炎作用的Th2细胞失衡。本研究对NTG患者外周血淋巴细胞进行HSP60刺激，观察Treg细胞在数量和功能上的缺陷情况；同时在血眼屏障破坏后的HSP60腹腔免疫动物模型中去除Treg细胞或调节其上游调控因素MALT1基因，观察Treg细胞缺陷下Th2细胞数量、功能改变、视网膜浸润情况，检测视网膜及血清抗体、细胞因子水平及RGC丢失情况，寻找自身免疫机制致RGC损伤的证据，为NTG的治疗提供新思路。

本研究通过临床样本及动物实验，运用多种分子生物学手段首先明确了NTG患者外周血淋巴细胞的表达情况及其在Treg细胞在数量和功能上的缺陷情况；其次在眼压正常的自身免疫性小鼠青光眼模型中，发现了细菌HSP与Th1细胞所介导的自身免疫反应可能是导致非眼压依赖性RGC丢失的主要原因，同时Treg缺陷引起的免疫耐受失衡加剧了这一过程。最后，在高眼压动物模型中发现小胶质细胞的激活极化可能参与了青光眼的免疫反应，导致RGC在解除高眼压后持续性丢失。综上所述，本研究为青光眼发病机制中的免疫相关因素提供了重要的理论支持，为青光眼的免疫学治疗提供了新思路。