Distinct transcriptome profiles of Gag-specific CD8+T cells temporally correlated with the protection elicited by SIV Delta nef live attenuated vaccine

• Type of Material: Article
• Authors: Wuxun Lu, University of Nebraska; Yanmin Wan, University of Nebraska; Fangrui Ma, University of Nebraska; R. Paul Johnson, Emory University; Qinghseng Li, University of Nebraska
• Language: English
• Date: 2017-03-23
• Publisher: PUBLIC LIBRARY SCIENCE
• Publication Version: Final Published Version
• Copyright Statement: © 2017 Lu et al
• License: Creative Commons Attribution 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.1371/journal.pone.0173929
• Title of Journal or Parent Work: PLOS ONE
• Volume: 12
• Issue: 3
• Start Page: e0173929
• End Page: e0173929
• Grant/Funding Information: This work was supported by NIH grant DK087625 (to Li, Q.). The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
• Keywords: CYTOTOXIC T-LYMPHOCYTES; Science & Technology - Other Topics; BLOCKADE; SIMIAN IMMUNODEFICIENCY VIRUS; Science & Technology; CD28 EXPRESSION; REPLICATION; IMMUNE-RESPONSES; RHESUS MACAQUES; Multidisciplinary Sciences; MEMORY; DIFFERENTIATION; CHALLENGE
• Research Categories: Biology, Neuroscience; Biology, Cell; Health Sciences, Immunology

Abstract

The live attenuated vaccine (LAV) SIVmac239Δnef (SIVΔnef) confers the best protection among all the vaccine modalities tested in rhesus macaque model of HIV-1 infection. This vaccine has a unique feature of time-dependent protection: Macaques are not protected at 3-5 weeks post vaccination (WPV), whereas immune protection emerges between 15 and 20 WPV. Although the exact mechanisms of the time-dependent protection remain incompletely understood, studies suggested that both cellular and humoral immunities contribute to this time-dependent protection. To further elucidate the mechanisms of protection induced by SIVΔnef, we longitudinally compared the global gene expression profiles of SIV Gag-CM9+ CD8+ (Gag-specific CD8+) T cells from peripheral blood of Mamu-A∗01+ rhesus macaques at 3 and 20 WPV using rhesus microarray. We found that gene expression profiles of Gag-specific CD8+ T cells at 20 WPV are qualitatively different from those at 3 WPV. At 20 WPV, the most significant transcriptional changes of Gag-specific CD8+ T cells were genes involved in TCR signaling, differentiation and maturation toward central memory cells, with increased expression of CCR7, TCRα, TCRΒ, CD28 and decreased expression of CTLA-4, IFN-γ, RANTES, granzyme A and B. Our study suggests that a higher quality of SIV-specific CD8+ T cells elicited by SIVΔnef over time contributes to the maturation of time-dependent protection.