IL-23/IL-17轴调控巨噬细胞极性进而影响视网膜新生血管形成的作用及机制研究

Neovascularization is the common pathological changes of many blinding eye diseases. Our previous studies have proved that macrophages are closely associated with RNV, and detected significantly high expression of IL-23 and IL-17A in neovascularized mice eyes . IL-17A was demonstrated to regulate RNV through modulating Mf polarization. Based on these previous findings, the current study hypothesized that IL-23/IL-17 axis affects retinal neovascularization via modulation of Mf polarization. Actually, this study is supposed to explore the role and modulation mechanisms of IL-23/IL-17 axis on Mf polarization and NV with the application of previously established RNV mice model with wild type or IL-17A knockout background and cell models mimicking retinal neovascularization diseases, to address the following issues:1. Whether Mf polarization induced by IL-17A is regulated by IL-23? 2. How IL-23/IL-17 axis modulates Mf polarization so as to influence RNV? Therefore, the current study is aimed to further clarify the potential role of Mf in IL-23/IL-17 axis modulation of RNV, thus providing fundamental evidence for IL-23/IL-17 axis and Mf as potential targets for the treatment of such retinal neovascularization diseases as diabetic retinopathy and proliferative vitreous retinopathy.

新生血管形成(NV)是许多致盲性眼病共有的病理改变。我们前期研究证实了巨噬细胞(Mf)与视网膜新生血管（RNV）形成密切相关,NV疾病小鼠视网膜IL-23、IL-17A表达显著升高，且IL-17A能参与调控Mf极化和RNV形成。基于此，本项目提出假说：IL-23/IL-17轴在RNV形成中通过参与调控Mf型别，进而影响NV形成。据此，本课题拟在野生型及IL-17A敲除小鼠RNV疾病模型和细胞膜型中探讨以下科学问题：1、IL-17A参与调节的Mf型别及效应变化是否受到IL-23调控？2、IL-23/IL-17轴如何调节Mf型别来发挥其影响RNV形成的作用？旨在进一步阐明Mf在IL-23/IL-17轴调控RNV形成中的潜在作用，进而为把IL-23/IL-17轴和Mf作为DR、PVR等NV性眼病的新治疗靶点提供坚实的实验依据。

本课题聚焦于视网膜新生血管形成，它是许多难治性致盲眼病的共同病理改变。课题组前期研究已证实炎症因子通过调控Mf极性影响新生血管形成。在此基础上，本课题进一步对IL-23/IL-17轴调控Mf极性进而影响RNV形成的机制进行了研究。课题组采用模拟DR病理机制的缺氧动物（OIR小鼠）、细胞模型，应用视网膜铺片、切片免疫荧光染色、RT-PCR、Western blot等检测方法，研究缺氧情况下视网膜IL-23/IL-17及相关炎症因子表达、巨噬细胞（Mf）数量及功能改变、NV发生情况的改变，结果发现：在OIR小鼠模型中，RNV的形成伴随视网膜中Mf流入增多、IL-23/IL-17因子、NLRP3表达增强，通过抑制IL-23/IL-17轴能减少Mf流入、NLRP3炎症小体活化及RNV形成；同时，研究发现IL-23通过IL-17促进Mf中NLRP3炎症小体活化，重组IL-23或IL-17蛋白可促进OIR小鼠视网膜中Mf增殖与迁移、RNV形成，而Mf消除后，IL-23/IL-17表达、NLRP3活化、RNV形成均减少。此外，课题组在研究过程中发现炎症因子IL-17对光感受器细胞具有保护作用：课题组研究发现缺氧情况下，OIR小鼠IL-17表达增加、Muller细胞活化增强，Muller细胞来源的神经营养因子NT-3可通过TrkC/ERK信号通路抑制缺氧情况下光感受器细胞凋亡；通过对IL-17基因敲除小鼠的研究发现，IL-17敲除能抑制缺氧情况下视网膜Muller细胞ERK信号通路活化、减少神经营养因子NT-3表达，进而光感受器细胞细胞凋亡增加。.基于上述研究结果，我们认为IL-23/IL-17轴、Mf有望成为VEGF以外的潜在抗NV形成的治疗靶点。本项目为进一步研究替代或联合抗VEGF疗法，治疗RNV性眼病提供了坚实的实验依据，具有潜在的临床应用指导意义。