High attenuation and immunogenicity of a simian immunodeficiency virus expressing a proteolysis-resistant inhibitor of NF-kappaB.
NF-kappaB/IkappaB proteins play a major role in the transcriptional regulation of human immunodeficiency virus, type-1 (HIV-1). In the case of simian immunodeficiency virus (SIV) the cellular factors required for the viral transcriptional activation and replication in vivo remain undefined. Here, we demonstrate that the p50/p65 NF-kappaB transcription factors enhanced the Tat-mediated transcriptional activation of SIVmac239. In addition, IkappaB-alpha S32/36A, a proteolysis-resistant inhibitor of NF-kappaB, strongly inhibited the Tat-mediated transactivation of SIVmac239. Based on this evidence, we have generated a self-regulatory virus by endowing the genome of SIV-mac239 with IkappaB-alpha S32/36A; the resulting virus, SIVIkappaB-alpha S32/36A, was nef-deleted and expressed the NF-kappaB inhibitor. We show that SIVIkappaB-alpha S32/36A was highly and stably attenuated both in cell cultures and in vivo in rhesus macaque as compared with a nef-deleted control virus. Moreover, the high attenuation was associated with a robust immune response as measured by SIV-specific antibody production, tetramer, and intracellular IFN-gamma staining of SIV gag-specific T cells. These results underscore the crucial role of NF-kappaB/IkappaB proteins in the regulation of SIV replication both in cell cultures and in monkeys. Thus, inhibitors of NF-kappaB could efficiently counteract the SIV/HIV replication in vivo and may assist in developing novel approaches for AIDS vaccine and therapy.
Quinto
Ileana
I
Department of Clinical and Experimental Medicine, Medical School, University of Catanzaro, 88100 Catanzaro, Italy. quinto@dbbm.unina.it
Puca
Antimina
A
Greenhouse
Jack
J
Silvera
Peter
P
Yalley-Ogunro
Jake
J
Lewis
Mark G
MG
Palmieri
Camillo
C
Trimboli
Francesca
F
Byrum
Russ
R
Adelsberger
Joseph
J
Venzon
David
D
Chen
Xueni
X
Scala
Giuseppe
G
D016915:AIDS Vaccines; D000818:Animals; D000914:Antibodies, Viral / Q000096:biosynthesis; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D002478:Cells, Cultured; D008253:Macaca mulatta; D016328:NF-kappa B / Q000037:antagonists & inhibitors* / Q000502:physiology; D015302:Simian Immunodeficiency Virus / Q000276:immunology* / Q000472:pathogenicity*; D020079:Terminal Repeat Sequences; D014613:Vaccines, Attenuated; D014779:Virus Replication
D016915:AIDS Vaccines; D000914:Antibodies, Viral; D016328:NF-kappa B; D014613:Vaccines, Attenuated