biostudies-literatureHess SMedical Research CouncilWellcome Trust100820https://www.ebi.ac.uk/biostudies/studies/S-EPMC9729881biostudies-literatureUnknown3(11)Ideal therapies for regenerative medicine or healthy aging require healthy organ growth and rejuvenation, but no organ-level approach is currently available. Using Mycobacterium leprae (ML) with natural partial cellular reprogramming capacity and its animal host nine-banded armadillos, we present an evolutionarily refined model of adult liver growth and regeneration. In infected armadillos, ML reprogram the entire liver and significantly increase total liver/body weight ratio by increasing healthy liver lobules, including hepatocyte proliferation and proportionate expansion of vasculature, and biliary systems. ML-infected livers are microarchitecturally and functionally normal without damage, fibrosis, or tumorigenesis. Bacteria-induced reprogramming reactivates liver progenitor/developmenCell reports. MedicineIn vivo partial reprogramming by bacteria promotes adult liver organ growth without fibrosis and tumorigenesis.PMC9729881MR/P011292/1095898/Z/11/ZYamane KHess SPena MAdams LKendall TJTruman RSoong DRambukkana AfalseIn vivo partial reprogramming by bacteria promotes adult liver organ growth without fibrosis and tumorigenesis.Ideal therapies for regenerative medicine or healthy aging require healthy organ growth and rejuvenation, but no organ-level approach is currently available. Using Mycobacterium leprae (ML) with natural partial cellular reprogramming capacity and its animal host nine-banded armadillos, we present an evolutionarily refined model of adult liver growth and regeneration. In infected armadillos, ML reprogram the entire liver and significantly increase total liver/body weight ratio by increasing healthy liver lobules, including hepatocyte proliferation and proportionate expansion of vasculature, and biliary systems. ML-infected livers are microarchitecturally and functionally normal without damage, fibrosis, or tumorigenesis. Bacteria-induced reprogramming reactivates liver progenitor/developmen2022-01-01T00:00:00Z2022 Nov2026-07-14T14:26:51.048Z2025-04-19T12:14:48.935ZS-EPMC97298813638410310.1016/j.xcrm.2022.100820