VEGFR-3对脉络膜新生血管的影响及其机制的初步研究

Choroidal neovascularization (CNV) is the leading cause of irreversible serious visual impairment in age-related macular degeneration. Suppression of CNV formation and development is the only effective treatment. It had been proved that vascular endothelial growth factor (VEGF) plays an important role in CNV production but its underlying mechanisms remain unclear. Our previous study found that VEGF receptor 3 was highly expressed in CNV tissues. The decreased expression of VEGFR-3 could inhibit the tube formation. The intravitreal injection of anti-VEGFR-3 antibody could significantly reduce CNV Lesion volume and fluorescence contrast leakage. In order to explore the effect of VEGFR-3 in pathogenesis of CNV, the present study aimed to culture hRVEC cells in vitro with VEGFR-3 overexpression or knockdown to study the effect of different stimuli and VEGFR-3 expression on hRVEC cells; In vitro co-culture of hRVEC and ARPE-19 cells, upregulation or downregulation of VEGFR-3 expression, mimicking the changes of the behavior of vascular endothelial cells. The mouse CNV model was constructed to verify the correlation between VEGFR-3 and CNV, and the retinal choroidal morphology and histopathological changes in mice after VEGFR-3 antagonism were also observed. The expression of ERK1/2, pERK1/2, PI3K and AKT in hRVECs with knockdown or overexpression of VEGFR-3 were collected, and the possible regulatory pathway connected the expression of VEGFR-3 with CNV occurrence and development was explored. This study will provide a new theoretical basis for exploring the pathogenesis of CNV and proving new potential therapeutic targets.

脉络膜新生血管（CNV）是年龄相关性黄斑变性发生不可逆性严重视力损伤的主要致病因素，抑制其生成和发展是目前唯一有效的治疗手段。VEGF在CNV生成中具有重要作用，但机制仍不甚明确。课题组前期研究发现VEGF受体3在CNV组织中高表达；siRNA敲减VEGFR-3抑制内皮细胞成管；VEGFR-3拮抗后CNV病灶容积缩小，渗漏减轻。为探索VEGFR-3在CNV发病中的作用机制，本课题拟通过研究研究不同刺激因素及VEGFR-3表达改变对内皮细胞成管的影响；共培养hRVEC和ARPE-19细胞，调节VEGFR-3表达观察其对血管内皮细胞功能的影响；观察抗VEGFR-3抗体作用后小鼠CNV形态与组织病理学改变；敲减或过表达VEGFR-3情况下检测ERK1/2、PI3K、AKT的表达水平，探索VEGFR-3在CNV中的可能调控通路。该研究将为探索CNV发病机制和新的潜在治疗靶点提供新的理论依据。

脉络膜新生血管（CNV）是年龄相关性黄斑变性发生不可逆性严重视力损伤的主要致病因素，抑制其生成和发展是目前唯一有效的治疗手段。VEGF在CNV生成中具有重要作用，但机制仍不甚明确。前期研究发现VEGFR-3在CNV组织中高表达；siRNA敲减VEGFR-3抑制内皮细胞成管。通过本项目的研究，我们对VEGFR-3在CNV发病中的作用机制进行了进一步的探讨。研究探索了炎症及促炎因子IFNγ通过RPE细胞表达VEGF-R3在CNV中发挥的作用，发现炎症刺激（IFNγ）可以导致RPE的VEGF-R3和VEGF-C表达均升高，初步阐释了其在RPE细胞中发挥的作用。此外，IFNγ处理同样可以上调HUVECs细胞的VEGF-R3表达。在体外培养siRNA 敲减VEGFR-3表达的hRVEC细胞中，给予不同浓度VEGF-A、VEGF-C、IFNγ处理，研究不同刺激因素及VEGFR-3表达改变对hRVEC细胞成管作用的影响，并明确不同刺激因素和VEGFR-3表达在内皮细胞成管过程中的协同或拮抗作用。此外，还通过小鼠CNV模型的玻璃体腔注射抗VEGFR-3抗体作用，观察小鼠CNV形态与组织病理学改变。总的来说，本项目的初步研究结果阐述了血管内皮细胞生长受体3（VEGFR-3）在脉络膜新生血管形成中的可能作用机制，且玻璃体腔注射抗VEGER-3抗体可以减小CNV病灶容积，这为CNV提供了潜在的新治疗靶点和理论依据。