In vivo expansion of gene-targeted hepatocytes through transient inhibition of an essential gene.
Marco De GiorgiSo Hyun ParkAdam CastorenoMingming CaoAyrea HurleyLavanya SaxenaMarcel A ChuecosChristopher J WalkeyAlexandria M DoerflerMia N FurgursonM Cecilia LjungbergKalyani R PatelSarah HydeTyler ChickeringStephanie LefebvreKelly WassarmanPatrick MillerJune QinMark K SchlegelIvan ZlatevRich Gang LiJong KimJames F MartinKarl-Dimiter BissigVasant JadhavGang BaoWilliam R LagorPublished in: bioRxiv : the preprint server for biology (2023)
Homology Directed Repair (HDR)-based genome editing is an approach that could permanently correct a broad range of genetic diseases. However, its utility is limited by inefficient and imprecise DNA repair mechanisms in terminally differentiated tissues. Here, we tested "Repair Drive", a novel method for improving targeted gene insertion in the liver by selectively expanding correctly repaired hepatocytes in vivo . Our system consists of transient conditioning of the liver by knocking down an essential gene, and delivery of an untargetable version of the essential gene in cis with a therapeutic transgene. We show that Repair Drive dramatically increases the percentage of correctly targeted hepatocytes, up to 25%. This resulted in a five-fold increased expression of a therapeutic transgene. Repair Drive was well-tolerated and did not induce toxicity or tumorigenesis in long term follow up. This approach will broaden the range of liver diseases that can be treated with somatic genome editing.