Direct in vivo protein transduction into a specific restricted brain area in rats

Attempts at protein transduction into specific restricted brain areas have remained unsuccessful. We attempted targeted, direct in vivo protein transduction by microinjecting β-galactosidase (β-gal) with hemagglutinating virus of Japan envelope (HVJ-E) vector into the rat nucleus tractus solitarius (NTS). The medulla oblongata including the NTS was removed 6 h post-injection and cryostat sections were histochemically stained to detect β-gal enzymatic activity. β-gal-positive cells were present in these sections as was β-gal activity determined by colorimetric analysis. β-gal-positive cells were not present in the rats microinjected only β-gal protein without HVJ-E vector. Our findings suggest that direct in vivo protein transduction into specific restricted brain areas is possible. The type of targeted delivery system we present may have wide applications in the administration of therapeutic proteins to the central nervous system.