Lohman BL, Van Rompay KK, McChesney MB, McGowan E, Joye S, Luciw P, Marthas M, Pedersen NC; Symposium on Nonhuman Primate Models for AIDS.
J Med Primatol. 1993 Sep-Oct; 22: abstract no. 60.
California Regional Primate Research Center, University of California, Davis 95616.
The molecularly cloned SIVmac1A11 is a model for a live virus vaccine because rhesus macaques infected with this virus are transiently viremic, do not develop disease, and withstand low-dose challenge with a pathogenic strain of SIVmac. The molecular clone SIVmac239 causes persistent viremia and a fatal immunodeficiency disease in macaques. Recombinant viruses constructed with reciprocal exchanges of the surface envelope from the genomes of 1A11 and 239 produce low-level persistent viremia and no disease 2 years after infection. We have evaluated these viruses as vaccines. Effectiveness was based on SIV-specific cellular and humoral immune responses before and after IV challenge with uncloned SIVmac251. Two years after initial infection 2 of 4 macaques infected with 1A11 and all macaques infected with the recombinant viruses had detectable CTL responses against p55-gag and gp160-env. None of the monkeys had SIV neutralization titers greater than 1:100. Following IV challenge with SIVmac251, all monkeys immunized with SIVmac1A11 became infected; 3 with persistent, high level viremia (> 10 TCID50 per 10(6) PBMC) while one was transiently infected (virus isolation negative after 2 weeks post challenge (pc)). Two of 3 monkeys immunized with the recombinant containing 239 env in 1A11 background were infected; one with persistent high level viremia, one with transient viremia. One remains virus isolation negative. Two out of 3 monkeys immunized with the recombinant containing 1A11 env in 239 background were infected; both with low level viremia (< or = 10 TCID50 per 10(6) PBMC). One monkey remains virus isolation negative. Lymph node biopsies were taken at 12 weeks pc for quantitation of virus load as a measure of persistent infection and the cultures are in progress. It appears the low level persistent viremia with these envelope recombinants increases their immunogenicity compared to SIVmac1A11.
Publication Types:
Keywords:
- Animals
- Antigens, Viral
- Gene Products, env
- Genes, env
- Genes, gag
- Macaca mulatta
- Membrane Glycoproteins
- Orthopoxvirus
- Simian immunodeficiency virus
- T-Lymphocytes, Cytotoxic
- Vaccines, Attenuated
- Viremia
- genetics
- gp120 protein, Simian immunodeficiency virus
- immunology
Other ID:
UI: 102207790
From Meeting Abstracts