The application of a lentiviral vector for gene transfer in fetal human hepatocytes

Background The applications of traditional retroviral vectors are limited b ecause proviral integrations into the host genome require DNA synthesis. Le ntiviruses are considered to be advantageous because of their ability to in fect non-dividing cells. Methods To demonstrate the potential of lentiviral vectors, we used a human immunodeficiency virus (HN)-1 virus encoding the green fluorescence protei n (GFP) to infect fetal human hepatocytes. GFP-expressing cells were transp lanted into the liver of Balb/C SCID mice via intrasplenic injection. Results Primary fetal hepatocytes incorporated the GFP reporter with high ( 30-40%) efficiency. A cell Line derived from human fetal liver (HFL) exhibi ted similar transduction efficiency to the lentiviral vector. To demonstrat e the relationship between lentiviral gene transfer and cell proliferation, cells were subjected to gamma-irradiation, which attenuated the replicatio n of primary fetal hepatocytes. However, lentiviral gene transfer was unaff ected by this decrease in cell proliferation. GFP expression in transduced cells was preserved during multiple passages in cell culture. When GFP-expr essing cells were transplanted into the liver of Balb/C SCID mice via intra splenic injection, GFP expression was observed throughout the 3 week durati on of the study. Conclusion These studies establish that human hepatocytes are amenable to l entiviral gene transfer with sustained transgene expression. Incorporation of lentiviral vectors will be helpful in testing strategies for hepatic gen e therapy. Copyright (C) 2000 John Wiley & Sons, Ltd.