title: A lymph node-derived cytopathic simian immunodeficiency virus Mne variant replicates in nonstimulated peripheral blood mononuclear cells.
abstract: Lymph nodes (LNs) are sites of active human immunodeficiency virus type 1 (HIV-1) and simian immunodeficiency virus (SIV) replication and disease at both early and late stages of infection. Consequently, variant viruses that replicate efficiently and subsequently cause immune dysfunction may be harbored in this tissue. To determine whether LN-associated SIVs have an increased capacity to replicate and induce cytopathology, a molecular clone of SIV was isolated directly from DNA extracted from unpassaged LN tissue of a pig-tailed macaque (Macaca nemestrina) infected with SIVMne. The animal had declining CD4+ T-lymphocyte counts at the time of the LN biopsy. In human CD4+ T-cell lines, the LN-derived virus, SIVMne027, replicated with relatively slow kinetics and was minimally cytopathic and non-syncytium inducing compared to other SIVMne clones. However, in phytohemagglutinin-stimulated pig-tailed macaque peripheral blood mononuclear cells (PBMCs), SIVMne027 replicated efficiently and was highly cytopathic for the CD4+ T-cell population. Interestingly, unlike other SIVMne clones, SIVMne027 also replicated to a high level in nonstimulated macaque PBMCs. High-level replication depended on the presence of both the T-cell and monocyte/macrophage populations and could be enhanced by interleukin-2 (IL-2). Finally, the primary determinant governing the ability of SIVMne027 to replicate in nonstimulated and IL-2-stimulated PBMCs mapped to gag-pol-vif. Together, these data demonstrate that LNs may harbor non-syncytium-inducing, cytopathic viruses that replicate efficiently and are highly responsive to the effects of cytokines such as IL-2.
authors.affiliation: Department of Microbiology, University of Washington, Seattle 98195, USA.
authors.forename: J T
authors.initials: JT
authors.lastname: Kimata
authors.forename: A
authors.initials: A
authors.lastname: Mozaffarian
authors.forename: J
authors.initials: J
authors.lastname: Overbaugh
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000821:virology; D002460:Cell Line; D002678:Chimera / Q000235:genetics; D003588:Cytopathogenic Effect, Viral; D005814:Genes, Viral; D015750:Genes, gag; D015751:Genes, pol; D014644:Genetic Variation; D006801:Humans; D066298:In Vitro Techniques; D007376:Interleukin-2 / Q000494:pharmacology; D007700:Kinetics; D007963:Leukocytes, Mononuclear / Q000276:immunology / Q000821:virology; D008198:Lymph Nodes / Q000821:virology; D008254:Macaca nemestrina; D008969:Molecular Sequence Data; D017386:Sequence Homology, Amino Acid; D016097:Simian Acquired Immunodeficiency Syndrome / Q000821:virology; D015302:Simian Immunodeficiency Virus / Q000235:genetics / Q000472:pathogenicity* / Q000502:physiology*; D014779:Virus Replication / Q000235:genetics
chemical_list: D007376:Interleukin-2