The study on mechanisms of species- and position-specific cartilage growth using human limb organoids

2021 Fiscal Year Final Research Report

• Project/Area Number: 20K22652
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0702:Biology at cellular to organismal levels, and related fields
• Research Institution: Kyoto University
• Principal Investigator: Tsutsumi Rio 京都大学, 高等研究院, 特定研究員 (60876241)
• Project Period (FY): 2020-09-11 – 2022-03-31
• Keywords: オルガノイド / 四肢発生 / 形態形成

Outline of Final Research Achievements

The research aims to establish reconstitutive models of limb cartilage morphogenesis in three-dimensional culture using the cells differentiated mouse and human pluripotent stem cells, to elucidate cellular behaviors governing tissue morphogenesis and their species-specificities. As there has not been an experimental model in which limb cartilage morphogenesis can be recapitulated in vitro, first we collected limb bud cells from mouse embryos and cultured them in a three-dimensional environment. We found the number, shapes, and growth of the cartilage could be manipulated in our model. Next, to establish human version of the in vitro limb morphogenesis model, we differentiated human pluripotent stem cells in two- and three-dimensional culture and recapitulated the morphogenetic process such that limb mesenchyme arise from the lateral plate and successfully derived limb mesenchyme-like cells.

Free Research Field

幹細胞工学、発生生物学、進化生物学

Academic Significance and Societal Importance of the Research Achievements

本研究では、三次元培養で四肢形態形成を再構成するモデルを新たに確立するとともに、ヒト肢芽細胞様の細胞を分化させることで、ヒトの四肢形態形成を培養下で再現することに繋がる成果を得た。このことは、以下4点の発展の可能性を切り開くものであったと考えている。(1)四肢発生に関わる分子が、どのような細胞挙動を制御し、それが組織レベルの形態変化に影響を及ぼすのかを明らかにする発生生物学的知見の解明。(2)四肢形態の種ごとの違いを細胞レベルで理解する進化発生学的知見の解明。(3)ヒトの四肢先天異常の原因となる遺伝変異や薬剤の検証モデルの確立。(4)ヒト四肢の欠損に対する移植治療の確立。