title: M1 polarization of human monocyte-derived macrophages restricts pre and postintegration steps of HIV-1 replication.
abstract: OBJECTIVE
  Functional polarization of human monocyte-derived macrophages (MDMs) into M1 cells leads to inhibition of R5 HIV-1 replication and viral DNA synthesis in comparison to control, unpolarized cells together with CD4 downregulation from the cell surface and upregulation of CCR5-binding chemokine secretion. We here investigated whether a postentry restriction of virus replication is also induced by M1 polarization of MDM.
  
  
  METHODS
  MDM were first polarized to M1 cells by 18 h stimulation with interferon-[gamma] and tumor necrosis factor-[alpha]; the cytokines were then removed and the cells were infected with vesicular stomatitis virus G-protein pseudotyped enhanced green fluorescence protein HIV-1 (HIV-GFP) generating a single-round infection cycle.
  
  
  METHODS
  HIV-1 expression was monitored in terms of eGFP expression by fluorescence activated cell sorter (FACS) analysis and real-time PCR analysis of total HIV-1 gag DNA, 2-long terminal repeat DNA, proviral DNA, and multiply spliced RNA transcripts. Expression of apolipopoprotein B mRNA-editing, enzyme-catalytic, polypeptide-like 3G (APOBEC3G), and APOBEC3A was tested by western blotting and FACS analysis.
  
  
  RESULTS
  Inhibition of HIV-GFP expression was observed in M1-MDM along with impaired viral DNA synthesis, delayed proviral integration, and reduced proviral transcription. Although APOBEC3G levels were similar in M1 and unpolarized MDM, APOBEC 3A was selectively expressed only by M1 cells.
  
  
  CONCLUSIONS
  M1 polarization of in-vitro differentiated primary MDM determines a transient, but profound restriction of HIV-1 replication affecting multiple (entry and postentry) steps in the virus life cycle likely involving the upregulated expression of APOBEC3A.
authors.forename: Luca
authors.initials: L
authors.lastname: Cassetta
authors.forename: Anna
authors.initials: A
authors.lastname: Kajaste-Rudnitski
authors.forename: Tiziana
authors.initials: T
authors.lastname: Coradin
authors.forename: Elisa
authors.initials: E
authors.lastname: Saba
authors.forename: Giulia
authors.initials: G
authors.lastname: Della Chiara
authors.forename: Marialuisa
authors.initials: M
authors.lastname: Barbagallo
authors.forename: Francesca
authors.initials: F
authors.lastname: Graziano
authors.forename: Massimo
authors.initials: M
authors.lastname: Alfano
authors.forename: Edana
authors.initials: E
authors.lastname: Cassol
authors.forename: Elisa
authors.initials: E
authors.lastname: Vicenzi
authors.forename: Guido
authors.initials: G
authors.lastname: Poli
mesh_terms: D002454:Cell Differentiation; D002478:Cells, Cultured; D017930:Genes, Reporter; D049452:Green Fluorescent Proteins / Q000032:analysis / Q000235:genetics; D015497:HIV-1 / Q000276:immunology* / Q000502:physiology*; D006801:Humans; D008264:Macrophages / Q000276:immunology* / Q000821:virology*; D018116:Vesiculovirus / Q000235:genetics; D014779:Virus Replication
chemical_list: C485184:enhanced green fluorescent protein; D049452:Green Fluorescent Proteins