Co-delivery of IL-2 or liposomes augment the responses of mice to a DNA vaccine for pseudorabies virus IE180.
Recently we have demonstrated, with a DNA vaccine, that the immediate early protein (IE180) of pseudorabies virus provides a moderate level of protection in mice. In order to improve its immunogenicity and protective capacity, this IE180 DNA vaccine was delivered to C3H/HeJ mice either in combination with an IL-2 expressing plasmid or complexed with cationic liposomes. Co-delivery of the vaccine and IL-2 DNA by gene gun resulted in seroconversion in 5/5 of the vaccinated mice after a single administration, whereas two intramuscular (i.m.) injections were required to achieve seroconversion in all mice. Antibody and delayed-type hypersensitivity responses were augmented in mice, which received the DNA vaccine and the IL-2 gene compared to those of mice receiving the DNA vaccine alone. In addition, the time of death after challenge was significantly delayed in mice, which received the IL-2 gene. The proportion of surviving mice (40%), however, was similar to that obtained in mice which received the vaccine alone by gene gun. Liposome-mediated vaccine delivery also resulted in a higher rate of seroconversion when compared with that induced by the naked DNA vaccine. Thus, all vaccinated mice seroconverted after either two i.v. or three i.m. injections of the liposome/DNA complex, with 40 and 25% of these mice being protected against challenge, respectively. These data support that co-administration of the IE180 DNA vaccine with the IL-2 gene or delivery in liposomes are two effective approaches to increase its immunogenicity.
Bu
J
J
Department of Pathobiology and Veterinary Science, University of Connecticut, Storrs, CT 06269, USA.
Song
Y
Y
Rompato
G
G
Burgess
D J
DJ
Garmendia
A E
AE
D000818:Animals; D000914:Antibodies, Viral / Q000096:biosynthesis / Q000097:blood; D005260:Female; D005822:Genetic Vectors; D011558:Herpesvirus 1, Suid / Q000276:immunology; D006968:Hypersensitivity, Delayed; D017874:Immediate-Early Proteins / Q000276:immunology*; D007273:Injections, Intramuscular / Q000662:veterinary; D007275:Injections, Intravenous / Q000662:veterinary; D007376:Interleukin-2 / Q000008:administration & dosage / Q000235:genetics* / Q000276:immunology; D008081:Liposomes; D051379:Mice; D008809:Mice, Inbred C3H; D011557:Pseudorabies / Q000517:prevention & control*; D022421:Pseudorabies Vaccines / Q000008:administration & dosage* / Q000235:genetics / Q000276:immunology; D019444:Vaccines, DNA / Q000008:administration & dosage* / Q000235:genetics / Q000276:immunology
D000914:Antibodies, Viral; D017874:Immediate-Early Proteins; D007376:Interleukin-2; D008081:Liposomes; D022421:Pseudorabies Vaccines; D019444:Vaccines, DNA; C047583:pseudorabies virus immediate early proteins