SIV escape mutants in rhesus macaques vaccinated with NEF-derived lipopeptides and challenged with pathogenic SIVmac251.
BACKGROUND
Emergence of viral variants that escape CTL control is a major hurdle in HIV vaccination unless such variants affect gene regions that are essential for virus replication. Vaccine-induced multispecific CTL could also be able to control viral variants replication. To explore these possibilities, we extensively characterized CTL responses following vaccination with an epitope-based lipopeptide vaccine and challenge with pathogenic SIVmac251. The viral sequences corresponding to the epitopes present in the vaccine as well as the viral loads were then determined in every macaque following SIV inoculation.


RESULTS
In most cases, the emergence of several viral variants or mutants within vaccine CTL epitopes after SIV challenge resulted in increased viral loads except for a single macaque, which showed a single escape viral variant within its 6 vaccine-induced CTL epitopes.


CONCLUSIONS
These findings provide a better understanding of the evolution of CD8+ epitope variations after vaccination-induced CTL expansion and might provide new insight for the development of an effective HIV vaccine.
Villefroy
Pascale
P
Institut Cochin, Département d'Immunologie, Hôpital Cochin, 27, rue du Faubourg Saint-Jacques, Paris, F-75014, France. villefroy@cochin.inserm.fr
Letourneur
Franck
F
Coutsinos
Zoe
Z
Mortara
Lorenzo
L
Beyer
Christian
C
Gras-Masse
Helene
H
Guillet
Jean-Gerard
JG
Bourgault-Villada
Isabelle
I
D000818:Animals; D015693:Gene Products, nef / Q000235:genetics / Q000276:immunology*; D008074:Lipoproteins / Q000235:genetics / Q000276:immunology; D008253:Macaca mulatta / Q000276:immunology* / Q000821:virology*; D009154:Mutation / Q000235:genetics; D012367:RNA, Viral / Q000097:blood; D018449:SAIDS Vaccines / Q000008:administration & dosage / Q000276:immunology*; D016097:Simian Acquired Immunodeficiency Syndrome / Q000276:immunology* / Q000821:virology*; D015302:Simian Immunodeficiency Virus / Q000235:genetics* / Q000276:immunology / Q000472:pathogenicity; D013602:T-Lymphocytes, Cytotoxic / Q000502:physiology; D019562:Viral Load; D014766:Viremia
D015693:Gene Products, nef; D008074:Lipoproteins; D012367:RNA, Viral; D018449:SAIDS Vaccines