Adenovirus vectors as potential vaccines against herpes simplex virus

Increased attention is being paid to adenoviruses as expression vectors and as recombinant virus vaccines. Adenovirus serotypes 4 and 7 have been administered orally to large numbers of military recruits as vaccines, and no adverse effects have been noted. We have constructed recombinant adenovirus vectors expressing glycoproteins of herpes simplex virus (HSV) that induce humoral and cellular immunity to HSV. Mice vaccinated with an adenovirus vector expressing HSV glycoprotein B (gB) were protected from a lethal challenge with HSV. Further studies are under way in monkeys to examine the possibility that oral administration of adenovirus vectors can produce protective immunity. In addition, adenovirus vectors have been used to identify viral antigens that are recognized by cytotoxic T lymphocytes and to further characterize these T cell responses. A small region in HSV gB, which acts as a major target for HSV-specific cytotoxic T lymphocytes, was defined with use of adenovirus vectors expressing deleted forms of gB.