I have over 20 years of research experience in stem cell biology and cellular reprogramming. Our group has recently developed a novel culture medium that reprograms PHHs into a proliferative precursor state, generating precursors of chemically expanded hepatocytes (pre-cHep). pre-cHep can undergo ~20 population doublings (~1 million-fold expansion) in 30 days while retaining liver repopulation capacity following transplantation into immunocompromised mice, unlike any other previously reported PHH alternatives. Upon in vitro differentiation, chemically expanded hepatocytes (cHep) exhibit mature hepatocyte characteristics, including ALBUMIN secretion and induction of CYP1A2, CYP3A4, and CYP2B6, closely resembling PHHs in 3D culture.