Establishment of UGT1A1-knockout human iPS-derived hepatic organoids for UGT1A1-specific kinetics and toxicity evaluation

Tomohiro Shintani; Chiharu Imamura; Yukiko Ueyama-Toba; Jumpei Inui; Akira Watanabe; Hiroyuki Mizuguchi

doi:10.1016/j.omtm.2023.08.003

Establishment of UGT1A1-knockout human iPS-derived hepatic organoids for UGT1A1-specific kinetics and toxicity evaluation

Mol Ther Methods Clin Dev. 2023 Aug 11:30:429-442. doi: 10.1016/j.omtm.2023.08.003. eCollection 2023 Sep 14.

Authors

Tomohiro Shintani¹, Chiharu Imamura², Yukiko Ueyama-Toba^{1

2

3

4}, Jumpei Inui¹, Akira Watanabe², Hiroyuki Mizuguchi^{1

2

3

4

5

6}

Affiliations

¹ Laboratory of Biochemistry and Molecular Biology, Graduate School of Pharmaceutical Sciences, Osaka University, Osaka 565-0871, Japan.
² Laboratory of Biochemistry and Molecular Biology, School of Pharmaceutical Sciences, Osaka University, Osaka 565-0871, Japan.
³ Laboratory of Functional Organoid for Drug Discovery, National Institute of Biomedical Innovation, Health and Nutrition, Osaka 567-0085, Japan.
⁴ Integrated Frontier Research for Medical Science Division, Institute for Open and Transdisciplinary Research Initiatives, Osaka University, Osaka 565-0871, Japan.
⁵ Global Center for Medical Engineering and Informatics, Osaka University, Osaka 565-0871, Japan.
⁶ Center for Infectious Disease Education and Research, Osaka University, Osaka 565-0871, Japan.

Abstract

Uridine diphosphate glucuronosyltransferases (UGTs) are highly expressed in the liver and are involved in the metabolism of many drugs. In particular, UGT1A1 has a genetic polymorphism that causes decreased activity, leading to drug-induced hepatotoxicity. Therefore, an in vitro evaluation system that accurately predicts the kinetics of drugs involving UGT1A1 is required. However, there is no such evaluation system because of the absence of the UGT1A1-selective inhibitor. Here, using human induced pluripotent stem (iPS) cells, genome editing technology, and organoid technology, we generated UGT1A1-knockout human iPS hepatocyte-derived liver organoids (UGT1A1-KO i-HOs) as a model for UGT1A1-specific kinetics and toxicity evaluation. i-HOs showed higher gene expression of many drug-metabolizing enzymes including UGT1A1 than human iPS cell-derived hepatocyte-like cells (iPS-HLCs), suggesting that hepatic organoid technology improves liver functions. Wild-type (WT) i-HOs showed similar levels of UGT1A1 activity to primary human (cryopreserved) hepatocytes, while UGT1A1-KO i-HOs completely lost the activity. Additionally, to evaluate whether this model can be used to predict drug-induced hepatotoxicity, UGT1A1-KO i-HOs were exposed to SN-38, the active metabolite of irinotecan, an anticancer drug, and acetaminophen and confirmed that these cells could predict UGT1A1-mediated toxicity. Thus, we succeeded in generating model cells that enable evaluation of UGT1A1-specific kinetics and toxicity.

Keywords: UGT1A1; drug metabolism; drug-induced hepatotoxicity; genome editing; hepatic organoids; human induced pluripotent stem cells.