Protection afforded by live attenuated SIV is associated with rapid killing kinetics of CTLs

Abstract

Background: Live attenuated SIV vaccines are highly efficacious, but how they mediate protection is poorly understood. A feature of the effectiveness of live attenuated vaccines is their ability to control high dose challenge viruses early, without a large peak of acute viraemia. We hypothesized that long-lived antigen exposure from live attenuated SIV may result in CD8+ cytotoxic T lymphocytes persistently capable of rapidly cytolytic potential. Methods: We employed a kinetic degranulation assay to study multiple tetramer+ SIV-specific CTL specificities before and after the SIVmac251 challenge of pigtail macaques inoculated with a live attenuated SIV. Results: Live attenuated SIV-vaccinated..