抑制iPLA2β增强视网膜色素上皮细胞在黄斑病变中的存活及视功能再建

Age related macular degeneration (AMD) is the most common cause of irreversible vision loss in elder people. There is currently no cure available. Fetal Retinal Pigment Epithelium cells (fRPE) has been confirmed with low immune response and has been used in one of the AMD clinical trials. Six AMD patients were enrolled and five showed vision improved. However, longer cell survival in diseased area and vision regeneration would needs to be clarified. We have showed that calcium-independent phospholipase A2β (iPLA2β) expresses in RPE cells and play an important role in RPE survival, proliferation, phagocytosis and apoptosis. This project would utilize dCas9-VP64 or dCas9-Krab system to induce or suppress the expression of iPLA2β, in NaIO3 induced ARPE-19/fRPE cell damage system, ex vivo ARPE-19/fRPE cell transplantation system, and in vivo transplantation system in rat, describe the possible protective role of iPLA2β inhibition. Furthermore, using fundus, OCT and ERG to compare the vision regeneration after transplantation with pre-treated iPLA2β-ARPE-19/fRPE. This study would describe a new protective way for transplanted RPE cells, which would also improve vision regeneration.

老年性黄斑病变(AMD)是导致中老年患者视功能下降的不可逆视网膜损伤，目前尚无有效治疗方法。胎儿来源的视网膜色素上皮细胞(fRPE)移植已经成为此类疾病重要细胞替代疗法。然而宿主局部病理微环境是制约移植后细胞长期疗效的瓶颈，从代谢调控角度能否实现fRPE的内源性保护并增强其在病理环境下的生存及疗效，尚不明确。我们前期证明iPLA2β参与RPE细胞凋亡，是下游分泌炎症物质前体的关键调控分子，因此抑制iPLA2β可能延长细胞在病变环境内存活并提高视功能。本项目拟利用dCas9体系调节iPLA2β表达，利用离体移植模型，观察iPLA2β表达的调节对RPE的保护效应，并建立NaIO3诱导大鼠RPE损伤模型，借助活体成像及功能检查与组织学方法确认低表达iPLA2β的RPE细胞于病变区域的存活能力及功能再建能力，阐明iPLA2β介导的内源性RPE保护机制，为新干预靶点提供依据。