Immunotolerance of islet transplantation using bioengineering cell sheet by induced loss of antigenicity

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K16282
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 55010:General surgery and pediatric surgery-related
• Research Institution: University of the Ryukyus (2020); Nagasaki University (2018-2019)
• Principal Investigator: Shinichiro Ono 琉球大学, 病院, 助教 (90567174)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: 膵島細胞移植 / 細胞シート / MHC class I / immunotolerance / loss of antigenicity

Outline of Final Research Achievements

To suppress the expression of HLA class I molecules, we designed guide RNA contrasts targeting β2 microglobulin that is required for the expression of HLA class I. Using lentiviral vector containing this guide RNA constructs, we generated HLA class I deficient HepG2 cell. We analyzed the expression of HLA of gene-edited T cells by flow cytometry analysis. By staining with HLA-A, B, C antibody, HLA deficient cells were found in approximately 25% of HepG2 cell. To enrich the HLA class I deficient cells, we performed beads selection and sorted HLA deficient cells with high purity, 99%. After establish of this technique, we adopted this technique to islet cell. In islet cell, MHC class I expression was not constant and could not be completed.

Free Research Field

膵島細胞移植

Academic Significance and Societal Importance of the Research Achievements

本研究の意義は2点ある。1．移植医療における安全確実な免疫寛容導入、2．臓器移植に取って代わる、より効率的な組織（細胞）移植の普及、である。免疫寛容導入については前述の如く移植医療の究極的ゴールであり、近年では制御性Ｔ細胞を用いた細胞療法などが試みられているが、「安全確実」とはいえず、やはり代替治療が望まれる。本研究のようにグラフトの抗原性を消失させる試みの成功例は過去に報告がなく、その独創性は極めて高いと考えたが、最終的な結果を得ることが出来なかった。