Hepatocyte-specific gene expression by baculovirus pseudotyped with vesicular stomatitis virus envelope glycoprotein.

We have developed the recombinant baculovirus pseudotyped with vesicular stomatitis virus (VSV) G protein. The VSV-G gene was under the control of the polyhedrin promoter so that it was expressed at high levels in infected insect cells but not in mammalian cells. The presence of VSV-G protein in purified baculovirus preparations was confirmed by Western analysis. This recombinant baculovirus also carried human AFP (alpha-fetoprotein) promoter for hepatocyte-specific gene expression. After an in vitro infection by a recombinant baculovirus carrying the luciferase gene under the control of human AFP promoter/enhancer (BacG-AFP-Luc(+)), the luciferase gene was expressed in AFP-producing Huh7, Hep3B, and HepG2 cell lines, but not in AFP-nonproducing cell lines. BacG-AFP-Luc(+) transduced with human hepatoma cells in vitro at an efficiency about fivefold greater than the recombinant baculovirus lacking VSV-G (the virus Bac-AFP-Luc(+)). The utilization of the AFP promoter/enhancer in a baculovirus vector could provide benefits in gene therapy applications.