The cellular interplay between RPE cells and macrophages through extracellular vesicles

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K09807
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 56060:Ophthalmology-related
• Research Institution: Kyoto Prefectural University of Medicine
• Principal Investigator: Hamuro Junji 京都府立医科大学, 医学(系)研究科(研究院), 客員教授 (80536095)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 網膜色素上皮細胞 / マイクロ / ミトコンドリア機能 / miR-494-3p / 細胞外小胞 / 加齢黄斑変性

Outline of Final Research Achievements

The production of MCP1, IL6 and VEGF was synergistically elevated when Mps and RPE cells were co-cultured. The protein expressions of these cytokines were increased even in Transwell inserts vertically connected with 0.40 μm membrane filters. Semi-purified CD63+ extracellular vesicle (EV) released from RPE cells, enhanced the secretion of these cytokines. Culture chamber separation horizontally connected with 0.03μm membrane filters reduced this increased cytokine secretion. The increased EV production was associated with elevated production of these cytokines from induced pluripotent stem cell-derived (iPS)-hRPE cells. The microarray analysis revealed a
the selectively increased release of miR-494-3p in EVs during the interplay with Mps. The transfection of the miR mimics modulated the functional homeostasis of mitochondria in hRPE cells through the inhibition of PTEN/PI3K signal pathway. MiR-494-3p may be a candidate molecular target for the diagnosis and therapy of AMD.

Free Research Field

細胞生物学、再生医療、免疫学

Academic Significance and Societal Importance of the Research Achievements

本研究は、RPEとMps間の細胞間ネットワークの破綻によるRPE細胞のミトコンドリア機能変性をAMDの早期病態の実態とする新概念である。病態増悪経路に細胞外小胞（EV）が関与することを明らかにし、miR494-3pを機能分子として同定したことは世界初である。本研究で確立した擬似モデル系を創薬探索系として活用することで、早期診断技術と併せてコンパニオン診断薬への道も拓かれる可能性も秘める。RPE細胞のミトコンドリア機能不全を修復する新規作用機序を持つAMD治療に繋げられる可能性がある。安価安全な医療・早期診断技術開発の基盤を構築するものである。