title: Bystander CD4+ T lymphocytes survive in HIV-infected human lymphoid tissue.
abstract: HIV infection is associated with depletion of CD4(+) T cells. The mechanisms of this phenomenon remain to be understood. In particular, it remains controversial whether and to what extent uninfected ("bystander") CD4(+) T cells die in HIV-infected individuals. We address this question using a system of human lymphoid tissue ex vivo. Tissue blocks were inoculated with HIV-1. After productive infection was established, they were treated with the reverse transcriptase inhibitor nevirapine to protect from infection those CD4(+) T cells that had not yet been infected. These CD4(+) T cells residing in HIV-infected tissue are by definition bystanders. Our results demonstrate that after nevirapine application the number of bystander CD4(+) T cells is conserved. Thus, in the context of HIV-infected human lymphoid tissue, productive HIV infection kills infected cells but is not sufficient to cause the death of a significant number of uninfected CD4(+) T cells.
authors.affiliation: Laboratory of Molecular and Cellular Biophysics, and NASA/NIH Center for Three-Dimensional Tissue Culture, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892, USA.
authors.forename: Jean-Charles
authors.initials: JC
authors.lastname: Grivel
authors.forename: Angelique
authors.initials: A
authors.lastname: Biancotto
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Ito
authors.forename: Rosangela G
authors.initials: RG
authors.lastname: Lima
authors.forename: Leonid B
authors.initials: LB
authors.lastname: Margolis
mesh_terms: D017209:Apoptosis; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology* / Q000502:physiology / Q000821:virology; D005434:Flow Cytometry; D015658:HIV Infections / Q000276:immunology / Q000473:pathology*; D015497:HIV-1 / Q000276:immunology*; D006801:Humans; D066298:In Vitro Techniques; D008221:Lymphoid Tissue / Q000166:cytology / Q000276:immunology / Q000821:virology*; D014066:Palatine Tonsil / Q000166:cytology / Q000821:virology