title: Generation of transmitted/founder HIV-1 infectious molecular clones and characterization of their replication capacity in CD4 T lymphocytes and monocyte-derived macrophages.
abstract: Genome sequences of transmitted/founder (T/F) HIV-1 have been inferred by analyzing single genome amplicons of acute infection plasma viral RNA in the context of a mathematical model of random virus evolution; however, few of these T/F sequences have been molecularly cloned and biologically characterized. Here, we describe the derivation and biological analysis of ten infectious molecular clones, each representing a T/F genome responsible for productive HIV-1 clade B clinical infection. Each of the T/F viruses primarily utilized the CCR5 coreceptor for entry and replicated efficiently in primary human CD4(+) T lymphocytes. This result supports the conclusion that single genome amplification-derived sequences from acute infection allow for the inference of T/F viral genomes that are consistently replication competent. Studies with monocyte-derived macrophages (MDM) demonstrated various levels of replication among the T/F viruses. Although all T/F viruses replicated in MDM, the overall replication efficiency was significantly lower compared to prototypic "highly macrophage-tropic" virus strains. This phenotype was transferable by expressing the env genes in an isogenic proviral DNA backbone, indicating that T/F virus macrophage tropism mapped to Env. Furthermore, significantly higher concentrations of soluble CD4 were required to inhibit T/F virus infection compared to prototypic macrophage-tropic virus strains. Our findings suggest that the acquisition of clinical HIV-1 subtype B infection occurs by mucosal exposure to virus that is not highly macrophage tropic and that the generation and initial biological characterization of 10 clade B T/F infectious molecular clones provides new opportunities to probe virus-host interactions involved in HIV-1 transmission.
authors.affiliation: Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA.
authors.forename: Christina
authors.initials: C
authors.lastname: Ochsenbauer
authors.forename: Tara G
authors.initials: TG
authors.lastname: Edmonds
authors.forename: Haitao
authors.initials: H
authors.lastname: Ding
authors.forename: Brandon F
authors.initials: BF
authors.lastname: Keele
authors.forename: Julie
authors.initials: J
authors.lastname: Decker
authors.forename: Maria G
authors.initials: MG
authors.lastname: Salazar
authors.forename: Jesus F
authors.initials: JF
authors.lastname: Salazar-Gonzalez
authors.forename: Robin
authors.initials: R
authors.lastname: Shattock
authors.forename: Barton F
authors.initials: BF
authors.lastname: Haynes
authors.forename: George M
authors.initials: GM
authors.lastname: Shaw
authors.forename: Beatrice H
authors.initials: BH
authors.lastname: Hahn
authors.forename: John C
authors.initials: JC
authors.lastname: Kappes
mesh_terms: D015496:CD4-Positive T-Lymphocytes / Q000276:immunology / Q000821:virology*; D002478:Cells, Cultured; D005260:Female; D016679:Genome, Viral; D015658:HIV Infections / Q000276:immunology / Q000821:virology*; D015497:HIV-1 / Q000235:genetics / Q000502:physiology*; D006801:Humans; D008264:Macrophages / Q000276:immunology / Q000821:virology*; D008297:Male; D008969:Molecular Sequence Data; D014779:Virus Replication