Induction or Type 1 Immune Responses to SIV by IFN-Gamma.
Abstract
We report the results of our experiment to address problems associated with efficacy of subunit vaccines and safety of live attenuated vaccines by inducing a Type 1 immune response using IFN-gamma Rhesus macaques were vaccinated with either a recombinant vaccinia virus (rVV) vaccine expressing the SIV gag, gp160, nef, and human lFN-gamma genes or one expressing only the three SlV proteins. The animals were given three inoculations of rVVs (0, 8, 26 weeks), boosted with baculovirus-expressed gag and gp 160 (61 weeks) and then inoculated with a high dose (100 TCID50) of a live attenuated SIV vaccine, SIV (63 weeks). All animals had low to undetectable virus titers by 14 weeks post-inoculation. Fifty weeks post-inoculation, the animals were challenged with 10 TCIDS0 of SIVmac251. Twelve weeks after the challenge, 80 % of the vaccinated animals have low to undetectable virus loads whereas the naive controls have high virus loads decreasing CD4+ cell counts and one animal has early signs of SAIDS. Monkeys that received the rVV expressing human IFN-gamma have lower but not statistically significant average virus loads and CD4+ cell counts. These results show that this vaccine regime is effective in decreasing virus load but not infection with a high dose intravenous challenge virus.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1999
- Accession Number
- ADA371068
Entities
People
- Tilahun D. Yilma
Organizations
- University of California