Development of induciblydiversified antibody-expressing cell library that enables antibody phenotypic screening

2021 Fiscal Year Final Research Report

• Project/Area Number: 19H02924
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 38060:Applied molecular and cellular biology-related
• Research Institution: Tokyo University of Pharmacy and Life Science
• Principal Investigator: TOMIZUKA KAZUMA 東京薬科大学, 生命科学部, 教授 (40444640)
• Co-Investigator(Kenkyū-buntansha): 堀田 秋津 京都大学, iPS細胞研究所, 講師 (50578002) ; 香月 康宏 鳥取大学, 医学部, 准教授 (90403401)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: ゲノム編集 / ヒト抗体 / 相補性決定領域 / Wnt/βカテニンシグナル / ペプチド医薬 / 指向性進化 / 抗体医薬

Outline of Final Research Achievements

The aim of this study is to create a cultured cell library expressing antibody molecules/peptides with more than 10 million of diverse specificities and to develop a technology to obtain functional antibodies/peptides by phenotypic screening using the library. In 293T cells, which express human antibody molecules on the plasma membrane, we optimized the conditions for genome editing targeting the CDR3 region of the human heavy chain, and succeeded in randomizing 10 amino acids with a high efficiency of more than 10%. This result indicates that a library size of more than 10 million per 100 million cells is feasible. Furthermore, after loading the Wnt / β-catenin signal reporter system on the above cell line, diversification is induced, and the search for the signal-regulating antibody and peptide is underway.

Free Research Field

ゲノム工学

Academic Significance and Societal Importance of the Research Achievements

哺乳類細胞において、ゲノム編集技術による標的蛋白質の10アミノ酸ランダム化が10%以上という高い効率で起こることが示された。すなわち、様々な表現型アッセイ系と本手法の組み合わせにより、これまで難しかった哺乳類細胞を用いた指向性進化研究が可能となると考える。また抗体・ペプチド創薬における表現型スクリーニングを可能とする本システムは、新規医薬候補品の創出に大きく寄与すると期待される。