title: Homeostatically Maintained Resting Naive CD4+T Cells Resist Latent HIV Reactivation.
abstract: Homeostatic proliferation (HSP) is a major mechanism by which long-lived naïve and memory CD4+T cells are maintainedin vivoand suggested to contribute to the persistence of the latent HIV-1 reservoir. However, while manyin vitrolatency models rely on CD4+T cells that were initially differentiated via T-cell receptor (TCR) stimulation into memory/effector cells, latent infection of naïve resting CD4+T cells maintained under HSP conditions has not been fully addressed. Here, we describe anin vitroHSP culture system utilizing the cytokines IL-7 and IL-15 that allows studying latency in naïve resting CD4+T cells. CD4+T cells isolated from several healthy donors were infected with HIV pseudotypes expressing GFP and cultured under HSP conditions or TCR conditions as control. Cell proliferation, phenotype, and GFP expression were analyzed by flow cytometry. RNA expression was quantified by qRT-PCR. Under HSP culture conditions, latently HIV-1 infected naïve cells are in part maintained in the non-dividing (= resting) state. Although a few HIV-1 provirus+cells were present in these resting GFP negative cells, the estimated level of GFP transcripts per infected cell seems to indicate a block at the post-transcriptional level. Interestingly, neither TCR nor the prototypic HDAC inhibitor SAHA were able to reactivate HIV-1 provirus from these cells. This lack of reactivation was not due to methylation of the HIV LTR. These results point to a mechanism of HIV control in HSP-cultured resting naïve CD4+T cells that may be distinct from that in TCR-stimulated memory/effector T cells.
authors.affiliation: Department of Medical Technology, School of Human Sciences, Tokyo University of TechnologyTokyo, Japan; Department of Immunology, National Institute of Infectious DiseasesTokyo, Japan.
authors.forename: Yasuko
authors.initials: Y
authors.lastname: Tsunetsugu-Yokota
authors.affiliation: Department of Immunology, National Institute of Infectious Diseases Tokyo, Japan.
authors.forename: Mie
authors.initials: M
authors.lastname: Kobayahi-Ishihara
authors.affiliation: Department of Immunology, National Institute of Infectious DiseasesTokyo, Japan; Department of Life Science and Medical Bioscience, Graduate School of Advanced Science and Engineering, Waseda UniversityTokyo, Japan.
authors.forename: Yamato
authors.initials: Y
authors.lastname: Wada
authors.affiliation: Department of Immunology, National Institute of Infectious Diseases Tokyo, Japan.
authors.forename: Kazutaka
authors.initials: K
authors.lastname: Terahara
authors.affiliation: Department of Life Science and Medical Bioscience, Graduate School of Advanced Science and Engineering, Waseda University Tokyo, Japan.
authors.forename: Haruko
authors.initials: H
authors.lastname: Takeyama
authors.affiliation: AIDS Research Center, National Institute of Infectious Diseases Tokyo, Japan.
authors.forename: Ai
authors.initials: A
authors.lastname: Kawana-Tachikawa
authors.affiliation: Department of Pathology, National Institute of Infectious Diseases Tokyo, Japan.
authors.forename: Kenzo
authors.initials: K
authors.lastname: Tokunaga
authors.affiliation: Graduate School of Frontier Sciences, University of Tokyo Tokyo, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Yamagishi
authors.affiliation: Infection Biology Group, Department of Experimental and Health Sciences, University Pompeu Fabra Barcelona, Spain.
authors.forename: Javier P
authors.initials: JP
authors.lastname: Martinez
authors.affiliation: Infection Biology Group, Department of Experimental and Health Sciences, University Pompeu FabraBarcelona, Spain; Institució Catalana de Recerca i Estudis Avançats (ICREA)Barcelona, Spain.
authors.forename: Andreas
authors.initials: A
authors.lastname: Meyerhans
keywords: HIV; cytokines; homeostatic proliferation; latency; naïve CD4 T cells