The activity of β-gal enzyme has been estimated within cells by using fluorescein isothiocyanate-cholera toxin B as a florescent probe that illustrates the level of GM1 ganglioside, the β-gal substrate.
Histological analysis showed that beta-Gal protein was expressed in vivo in the lungs and the CLN of animals immunized with i.n. administered beta-Gal DNA.The immune responses generated by i.n. administration of gB DNA with or without cholera toxin (CT) were compared to those generated by intramuscular (i.m.) gB DNA and i.n. live HSV administration.Three i.n. doses of gB DNA over a 3-week period resulted in a distal mucosal immunoglobulin A (IgA) response.