巨噬细胞集落刺激因子诱导的M2样小胶质细胞对氧诱导视网膜病变中血管化进程的作用及机制研究

Present study about molecular mechanism of ischemic retinopathy are largely unknown, the therapeutic modalities to limit the adverse consequences of aberrant neovascularization are invasive and /or tissue-destructive. Rather than prevent or eliminate the neovasculature, we propose to improve the vascularition. Microglial cells are the resident macropahges in retina, they can scan their territorial domains by communicate with retina neurons. More recently, a potential role of microglia in retinal blood vessel formation has been suggested. But the molecular mechanism of cross-talk between microglia and blood vessel are not clearly understood. Notch1/DII4 are the important negative regulator to inhibit pathological neovascularization. Previous research suggested Notch1/DII4 maybe the signal between microglia and vascular tip cells. Study are administrated in oxygen-induced-retinopathy mice, with co-culture of microglia and endothelial cells. The purpose of the study is to observe the M2-like microglia in the retina of M-CSF administrated and the relationship between microglia and vascular repair. Overexpression or silence Notch1 gene in M2-like microglia are used to demonstrated if the notch1 is a key regulator in vascular tube formation in vivo. DII4-Fc are used to inhibited Notch1/DII4 pathway to explore the cross-talk between M2-like microglia and vascular tip cells. This study will explore the molecular mechanism between microglia and vascular repair in ischemic retinopathy and provide a new target.

视网膜缺血性疾病的分子病理机制及治疗仍是目前研究的难点。近年来的治疗方法大多针对其并发症，均不能有效改善和恢复视网膜血供，如何改善视网膜微环境、促进无血管灌注区视网膜正常血管化，成为这类疾病防治研究中的关键。视网膜微环境中小胶质细胞的作用研究日益突出，它除了与神经细胞对话外，还可促进视网膜无灌注区尽快血管化，但是该过程的具体分子对话机制仍不清楚。研究提示Notch1/DII4可能是小胶质细胞和新生血管芽尖端对话的重要信号分子。本研究采用氧诱导视网膜病变模型，体外小胶质细胞和微血管内皮细胞共培养模式，研究巨噬细胞集落刺激因子诱导的视网膜M2样小胶质细胞增加和视网膜无灌注区血管化进程的时空变化关系，分析二者之间的关联，并深入探讨M2样小胶质细胞和新生血管芽尖端对话的信号途径，阐明M2样小胶质细胞和血管芽吻合成枝之间的分子机制，为视网膜缺血性疾病开拓新治疗思路。

我们研究了OIR模型中视网膜MG细胞的谱系变化。选取ob/ob小鼠作为缺血性视网膜病变早期模型，观察研究MG细胞的谱系变化。根据其动态变化过程，分析研究DR模型及其他缺血性视网膜病变模型早期缺血-血管闭塞-新生血管阶段MG变化、免疫反应及血管的关系的动态变化。根据巨噬细胞性质特点，我们亦研究了thioridazine在体外对黑色素瘤的影响。细胞实验发现高剂量的thioridazine可以更明显地抑制黑色素肿瘤细胞增殖。Thioridazine体外可诱导肿瘤细胞发生自噬，体内也有一定抗肿瘤作用。通过观察流式细胞术检测肿瘤相关巨噬细胞和自然杀伤细胞（NK细胞）的变化，进一步验证了thioridazine肿瘤微环境中免疫细胞影响着肿瘤的生长和转移等生物学行为。同时我们发现thioridazine治疗组，肿瘤血管的数量明显下降，说明thioridazine在体内的抗肿瘤作用可能与其抗血管生成相关。