Adenine base editing rescues disrupted BCKDH function and reduces BCAAs toxic accumulation in maple syrup urine disease patient iPSC-hepatic organoids

作者：Haiyan Zhang, Zirui Wan, Xiaomei Li, Bin Wang, Jingyun Guan, Yue Li, Xiaohua Jin, Xu Ma, Guohua Liu · 发表于：Stem Cell Research & Therapy · 年份：2025 · DOI：10.1186/s13287-025-04630-w · 被引用次数：3 · 研究领域：Metabolism and Genetic Disorders、Genomics and Rare Diseases、Pharmacogenetics and Drug Metabolism

BACKGROUND: Maple syrup urine disease (MSUD) is an inherited metabolic disorder caused by a deficiency in the activity of the hepatic branched-chain α-ketoacid dehydrogenase (BCKDH) complex, which leads to the toxic accumulation of three branched-chain amino acids (BCAAs) and their respective α-ketoacid, resulting in severe neurotoxicity, coma and even death without effective therapeutic measures. METHODS: In this study, we established the patient induced pluripotent stem cells (iPSC)-derived hepatic organoids (HOs), analyzed the characteristics, and applied adenine base editor (ABE8e) to correct a mutation (T322I) of the BCKDHB (branched chain keto acid dehydrogenase E1, beta polypeptide) gene in patient induced pluripotent stem cells (iPSC)-derived hepatic organoids (HOs). qRT-PCR and western blot analysis were performed to assess the expression level of BCKDHA (branched chain keto acid dehydrogenase E1, alpha polypeptide) and BCKDHB. The effects of base editing were comprehensively analyzed using both bulk RNA sequencing and single-cell RNA sequencing (scRNA-Seq). RESULTS: Immunofluorescence and RT-PCR arrayed the high expression of hepatoblast specific proteins in HOs, such as α-1-anti-trypsin (A1AT), hepatocyte nuclear factor-4-alpha (HNF4A), cytokeratin18 (CK18), albumin (ALB), cytochrome P450 family 3 subfamily A member 4 (CYP3A4) and cytochrome P450 family 3 subfamily A member 7(CYP3A7). Functional experiments indicated that these HOs recapitulated characteristics of ...