K. Venugopal et al., IMMUNITY TO ST-LOUIS ENCEPHALITIS-VIRUS BY SEQUENTIAL IMMUNIZATION WITH RECOMBINANT VACCINIA AND BACULOVIRUS DERIVED PRM E PROTEINS/, Vaccine, 13(11), 1995, pp. 1000-1005
St. Louis encephalitis (SLE) is an important mosquito-borne disease of
great public health concern in parts of the United States, South Amer
ica and Canada. Protective immunogens of flaviviruses produced in diff
erent expression systems have been shown to be effective against virul
ent virus infection in laboratory animal models. Here we show that the
pre-membrane and envelope (PrM/E) of SLE virus expressed in insect an
d mammalian cell systems using baculovirus and vaccinia virus, respect
ively, are processed correctly and showed similar antigenic characteri
stics as the authentic proteins, Immunization with the recombinant pro
teins individually or in combination resulted in neutralizing and prot
ective immune responses. A schedule consisting of initial immunization
with recombinant vaccinia virus followed by a secondary boost with re
combinant baculovirus protein resulted in higher levels of neutralizin
g and protective immune responses. The advantages of the use of such a
combined approach as a general immunization strategy are discussed.