title: HIV-2 infects resting CD4+ T cells but not monocyte-derived dendritic cells.
abstract: BACKGROUND
  Human Immunodeficiency Virus-type 2 (HIV-2) encodes Vpx that degrades SAMHD1, a cellular restriction factor active in non-dividing cells. HIV-2 replicates in lymphocytes but the susceptibility of monocyte-derived dendritic cells (MDDCs) to in vitro infection remains partly characterized.
  
  
  RESULTS
  Here, we investigated HIV-2 replication in primary CD4+ T lymphocytes, both activated and non-activated, as well as in MDDCs. We focused on the requirement of Vpx for productive HIV-2 infection, using the reference HIV-2 ROD strain, the proviral clone GL-AN, as well as two primary HIV-2 isolates. All HIV-2 strains tested replicated in activated CD4+ T cells. Unstimulated CD4+ T cells were not productively infected by HIV-2, but viral replication was triggered upon lymphocyte activation in a Vpx-dependent manner. In contrast, MDDCs were poorly infected when exposed to HIV-2. HIV-2 particles did not potently fuse with MDDCs and did not lead to efficient viral DNA synthesis, even in the presence of Vpx. Moreover, the HIV-2 strains tested were not efficiently sensed by MDDCs, as evidenced by a lack of MxA induction upon viral exposure. Virion pseudotyping with VSV-G rescued fusion, productive infection and HIV-2 sensing by MDDCs.
  
  
  CONCLUSIONS
  Vpx allows the non-productive infection of resting CD4+ T cells, but does not confer HIV-2 with the ability to efficiently infect MDDCs. In these cells, an entry defect prevents viral fusion and reverse transcription independently of SAMHD1. We propose that HIV-2, like HIV-1, does not productively infect MDDCs, possibly to avoid triggering an immune response mediated by these cells.
authors.forename: Lise
authors.initials: L
authors.lastname: Chauveau
authors.forename: Isabel
authors.initials: I
authors.lastname: Puigdomenech
authors.forename: Diana
authors.initials: D
authors.lastname: Ayinde
authors.forename: Ferdinand
authors.initials: F
authors.lastname: Roesch
authors.forename: Françoise
authors.initials: F
authors.lastname: Porrot
authors.forename: Daniela
authors.initials: D
authors.lastname: Bruni
authors.forename: Benoit
authors.initials: B
authors.lastname: Visseaux
authors.forename: Diane
authors.initials: D
authors.lastname: Descamps
authors.forename: Olivier
authors.initials: O
authors.lastname: Schwartz
mesh_terms: D015496:CD4-Positive T-Lymphocytes / Q000821:virology*; D002478:Cells, Cultured; D003713:Dendritic Cells / Q000821:virology*; D015498:HIV-2 / Q000502:physiology*; D006801:Humans; D054334:Viral Regulatory and Accessory Proteins / Q000378:metabolism; D053586:Virus Internalization; D014779:Virus Replication
chemical_list: C074286:VPX protein, Human immunodeficiency virus 2; D054334:Viral Regulatory and Accessory Proteins