Nonviral HVJ (Hemagglutinating Virus of Japan) Liposome-Mediated Retrograde Gene Transfer of Human Hypatocyte Growth Factor in the Rat Nervous System Promotes Functional and Histological Recovery of Crushed Nerve

Hepatocyte growth factor (HGF) is known to be involved in many biological functions, such as organ regeneration and angiogenesis, as well as exerting neurotrophic effects on motor, sensory, and parasympathetic neurons. In this study, the authors gave repeated intramuscular injections of the human HGF gene, using a nonviral hemagglutinating virus of Japan (HVJ) liposome method, to examine whether transfection of the rat nervous system with this gene was able to exert neurotrophic effects to facilitate recovery of a crushed nerve. The expression of HGF protein and HGF mRNA indicated that gene transfer into the nervous system did occur via retrograde axonal transport. At 4 weeks after crush, electrophysiological examination of the crushed nerve showed a significantly shorter mean latency and a significantly greater mean maximum M-wave amplitude with repeated injections of HGF gene. Furthermore, histological findings showed that the mean diameter of the axons, the axon number, and the axon population were significantly larger in the group with the repeated injections of HGF gene. The results showed that repeated human HGF gene transfer into the rat nervous system was able to promote crushed nerve recovery, both electrophysiologically and histologically, and suggested that HGF gene transfer has the potential for the treatment of human crushed nerve.