Abstract
To examine the possibility of gene transfer into tissue-engineered human oral epithelium using a gene gun, we transferred the β-galactosidase expression vector and Hepatitis B surface antigen (HBsAg) expression vector as a marker gene. The gene gun uses gold particles coated with DNA and directly bombards the tissue. This approach of allowing DNA to penetrate directly through cell membranes into cytoplasm or even nuclei is highly effective for gene delivery. We evaluated the efficiency, the efficacy of gene transfer into the tissue-engineered oral epithelium in vitro at several pressures of helium gas, and the duration of transfected gene expressions. High β-galactosidase activity with low damage to the tissue-engineered epithelium was found at 300-350 psi using helium gas. HBsAg expressions were detected by radioimmunoassay (RIA) in the culture medium from day 1 to 13, reaching a maximum at day 3 after bombardment. These results suggest that the gene gun may be a feasible and effective tool for the tissue-engineered oral epithelial gene transfer.
