INVESTIGATION OF PROMOTER FUNCTION IN HUMAN AND ANIMAL-CELLS INFECTEDWITH HUMAN RECOMBINANT ADENOVIRUSES EXPRESSING ROTAVIRUS ANTIGEN VP7SC

Human adenovirus (Ad) vectors are being used increasingly for a variet y of applications in vaccination and gene therapy. The ability of vect ors to enter cells and the efficiency of promoters expressing the ther apeutic gene or vaccine antigen are critical to the outcome of such ex periments. To identify promoters which might be suitable for use under a variety of conditions we have investigated the expression of a rota virus antigen, VP7sc, employing several commonly used promoters carrie d in E1-substituted Ad vectors both in cell types which support virus replication and in cells which do not. Although not all gene construct ions were identical, wide variations in promoter function were evident even in human 293 cells which support virus replication. The simian v irus type 40 (SV40) early and beta-actin promoters expressed poorly; t he SV40 late promoter was somewhat better. The human IE94 cytomegalovi rus (CMV) promoter and a modified Ad major late promoter were best, fu nctioning equally well but with different kinetics. In other human cel l lines the CMV promoter was more versatile, generally providing susta ined expression at a significant level, in one case for at least 6 day s. In addition, as mouse, rabbit and pig models of rotavirus infection are under investigation and VP7sc is a vaccine antigen, we also inves tigated the ability of the recombinant adenoviruses to infect cells fr om these and other sources. VP7sc expression was detected in several h eterologous cell types, illustrating the ubiquity of the human Ad rece ptor and the versatility of human Ad as vectors when suitable promoter s are used.