Intramuscular injection of an expression vector containing the gene for HIV gp 120 induces antibodies to the gp 120 protein.
Int Conf AIDS 1990 Jun 20-23; 6:326 (abstract no. 1048) Rhodes G, Felgner P, Wolff J, Haigwood N; Vical Inc., San Diego, California, USA
It has recently been demonstrated that the injection of DNA containing reporter genes into mouse muscle results in the expression of substantial amounts of the protein encoded by the gene [J. Wolf et al., Science, in press]. We have investigated the usefulness of this technique for immunization. We employed a construct consisting of a CMV early promotor which drives the synthesis of the gp-120 protein from HIV. The protein retains the signal sequences and is efficiently secreted from the cell. Two immunization procedures were tested. (1) Mice were injected intermuscularly with 20 ug of this plasmid. (2) Mouse fibroblasts were transfected using cationic liposomes and the transfected cells were injected. Serum samples were obtained weekly and assayed for the presence of IgG + IgM antibodies to gp-120. In both cases we find that a single injection produces a transient immune response which peaks between one and two weeks after injection. One of the major problems of recombinant subunit vaccines is that the antigen is seldom properly glycosylated in the heterologous expression systems used to produce the protein. This delivery technique may provide a solution to this problem since the antigen is produced in the host species of the virus.
Keywords: AEGIS, Genetic Vectors, Antibodies, Injections, Intramuscular, Glycoproteins, Plasmids, HIV, Vaccines, Synthetic, Indicators and Reagents, DNA, Immunization, Liposomes, Laboratory Techniques and Procedures, Promoter Regions (Genetics), Mice, Inbred BALB C, Mice, Animal, genetics, ICA6
