DNA IMMUNIZATION OF NEONATES INDUCES IMMUNITY DESPITE THE PRESENCE OFMATERNAL ANTIBODY

Neonatal animals were not considered as suitable vaccine recipients ei ther because of immune immaturity or because passively delivered antib ody interferes with immune induction. In this report, we evaluated the response of neonatal mice to immunization with naked DNA encoding a h erpes simplex virus (HSV) protein, and determined if maternally derive d HSV antibody interfered with immunogenicity. Our results show that n eonatal mice develop effective humoral and T cell responses after immu nization with either DNA or inactivated vaccines. The nature of the re sponses to HSV immunization, however, was more Th2-like in neonates th an in adults. Whereas neonatal mice from HSV-naive mothers responded w ell to both DNA and inactivated vaccines, only DNA immunization induce d effective immunity in neonates born to immune mothers. Our results i ndicate that DNA vaccines might provide a useful means of immunizing y oung animals that still possess high levels of potentially interfering maternal antibody.