TY - JOUR
T1 - Reduced Virus Load in Rhesus Macaques Immunized with Recombinant gp160 and Challenged with Simian Immunodeficiency Virus
AU - Ahmad, Shabbir
AU - Lohman, Barbara
AU - Marthas, Marta
AU - Giavedoni, Luis
AU - el-Amad, Zahwa
AU - Haigwood, Nancy L.
AU - Scandella, Carl J.
AU - Gardner, Murray B.
AU - Luciw, Paul A.
AU - Yilma, Tilahun
N1 - Copyright:
Copyright 2017 Elsevier B.V., All rights reserved.
PY - 1994/2
Y1 - 1994/2
N2 - As a safe alternative to inactivated and live-attenuated whole-virus SIV vaccines, we have evaluated the potential of SIVmac239 gp160 expressed by recombinant vaccinia virus (vSIVgp160) and baculovirus (bSIVgp160) to protectively immunize rhesus macaques against intravenous (iv) infection with pathogenic SIVmac isolates. Macaques were immunized with live vSIVgp160 and/or bSIVgp160 protein partially purified from insect cells. The challenge viruses, propagated in rhesus peripheral blood mononuclear cells, consisted of the molecular clone SIVmac239 and another genetically similar, uncloned isolate, SIVmac251. Although antibodies that bind gp130 were induced in all animals following immunization with SIVgp160, neutralizing antibodies were undetectable 1 week prior to virus challenge. These results differ from those for macaques vaccinated with inactivated, whole SIV. All animals became infected after iv inoculation with 1–10 AID50 of either challenge virus. For animals challenged with SIVmac251, but not those challenged with SIVmac239, the cell-free infectious virus load in plasma of vSIVgp160-primed, bSIVgp160-boosted macaques was significantly lower than in unimmunized controls at 2 weeks postchallenge. Virus virulence, immunization regimen, and challenge with homologous or heterologous virus are factors critical to the outcome of the study. Immunization with surface glycoprotein may not necessarily provide protective immunity against infection but may reduce virus load. The relationship between reduction in virus load by vaccination and delay in onset of disease remains to be determined.
AB - As a safe alternative to inactivated and live-attenuated whole-virus SIV vaccines, we have evaluated the potential of SIVmac239 gp160 expressed by recombinant vaccinia virus (vSIVgp160) and baculovirus (bSIVgp160) to protectively immunize rhesus macaques against intravenous (iv) infection with pathogenic SIVmac isolates. Macaques were immunized with live vSIVgp160 and/or bSIVgp160 protein partially purified from insect cells. The challenge viruses, propagated in rhesus peripheral blood mononuclear cells, consisted of the molecular clone SIVmac239 and another genetically similar, uncloned isolate, SIVmac251. Although antibodies that bind gp130 were induced in all animals following immunization with SIVgp160, neutralizing antibodies were undetectable 1 week prior to virus challenge. These results differ from those for macaques vaccinated with inactivated, whole SIV. All animals became infected after iv inoculation with 1–10 AID50 of either challenge virus. For animals challenged with SIVmac251, but not those challenged with SIVmac239, the cell-free infectious virus load in plasma of vSIVgp160-primed, bSIVgp160-boosted macaques was significantly lower than in unimmunized controls at 2 weeks postchallenge. Virus virulence, immunization regimen, and challenge with homologous or heterologous virus are factors critical to the outcome of the study. Immunization with surface glycoprotein may not necessarily provide protective immunity against infection but may reduce virus load. The relationship between reduction in virus load by vaccination and delay in onset of disease remains to be determined.
UR - http://www.scopus.com/inward/record.url?scp=0028220153&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0028220153&partnerID=8YFLogxK
U2 - 10.1089/aid.1994.10.195
DO - 10.1089/aid.1994.10.195
M3 - Article
C2 - 8198872
AN - SCOPUS:0028220153
SN - 0889-2229
VL - 10
SP - 195
EP - 204
JO - AIDS Research and Human Retroviruses
JF - AIDS Research and Human Retroviruses
IS - 2
ER -