X-Gal histology in murine colon transduced by vesicular stomatitis virus G protein (VSV-G)-pseudotyped lentivirus (LV) encoding β-Gal in vivo. The time course of β-Gal expression in the colon of BALB/c mice. Each group had 6 mice. The colon was removed at the indicated time points. The number of X-Gal-positive cells in murine colon transduced by LV-β-Gal in vivo. All values were expressed as means ± SD. *p < 0.05 compared with the results of normal control (NC).