PROTECTIVE IMMUNITY AGAINST RESPIRATORY SYNCYTIAL VIRUS IN EARLY-LIFEAFTER MURINE MATERNAL OR NEONATAL VACCINATION WITH THE RECOMBINANT-G FUSION PROTEIN BBG2NA

Maternal and neonatal immunization were evaluated for their capacity t o induce protective immunity against respiratory syncytial virus (RSV) lower respiratory tract infections in early life. Murine models were studied by use of a novel recombinant vaccine candidate, designated BB G2Na, which was derived in part from the RSV (Long) G protein. Materna l immunization resulted in the passive transfer of high levels of RSV- A antibodies to the offspring, which protected them from RSV challenge for up to 14 weeks. Indeed, protection correlated with the detection of RSV antibodies in the serum. Neonatal immunization with BBG2Na indu ced significant antibody responses even in the first week of life. Mos t importantly, these neonatal responses were not inhibited by the pres ence of RSV maternal antibodies. Consequently, the combination of mate rnal and neonatal immunization with BBG2Na resulted in the continual p resence of protective levels of antibodies in the offspring.