Wang S, Manning S, Kensil C, Lu S; Conference on Advances in AIDS Vaccine Development.
Conf Adv AIDS Vaccine Dev 1997 Conf Adv AIDS Vaccine Dev 1997 Bethesda Md. 1997 May 4-7; 120 (Poster 15).
University of Massachusetts Medical Center, Worcester, MA. Fax: (508) 856-5981.
Raising a higher and more persistent immune response is critical in developing a DNA-based vaccine against HIV-1 infections. One potential method of optimization is the use of an immunological adjuvant with the DNA-based vaccines. QS-21 was selected for its known adjuvant effect for subunit vaccines. Groups of 6-8 week old female Balb/C mice were gene-gun inoculated with DNA vaccines encoding for HIV-1 gp120 envelope proteins with or without a QS-21 injection. QS-21 was given subcutaneously at the same skin site of gene gun inoculation two days prior to or one day post DNA immunizations. Each mouse received two DNA immunizations separated one month apart. Serum anti-gp120 IgG levels were examined by ELISA after primary and booster immunizations. QS-21 was effective in stimulating higher antibody responses after the booster immunization when it was given two days prior to DNA immunizations. In contrast, no adjuvant effect was observed if QS-21 was given one day post-DNA immunization. Mice receiving DNA vaccine alone, or with QS-21 one day post DNA immunizations, had an anti-gp120 IgG titer of 1:900 while those receiving QS-21 two days prior to the DNA immunizations had an anti-gp120 titer of 1:8100, a 9-fold increase from the usual level. QS-21 did not cause a shift in antibody isotypes. Anti-gp120 antibodies in all of the above study groups are predominantly IgG1 subtype. DNA vaccination is effective in inducing antibody responses against conformational epitopes but its use may be limited if it is unable to mount strong immune responses against certain weak antigens. Including effective adjuvants in a DNA vaccination regimen may provide a viable approach to overcome this problem.
Publication Types:
Keywords:
- Adjuvants, Immunologic
- Animals
- Female
- Gene Products, env
- Genes, env
- HIV Envelope Protein gp120
- HIV Infections
- HIV-1
- Immunization
- Immunization, Secondary
- Mice
- QS 21
- Saponins
- Vaccination
- Vaccines, DNA
- genetics
- immunology
Other ID:
UI: 102225667
From Meeting Abstracts