title: Establishment of a novel CCR5 and CXCR4 expressing CD4+ cell line which is highly sensitive to HIV and suitable for high-throughput evaluation of CCR5 and CXCR4 antagonists.
abstract: BACKGROUND
  CCR5 and CXCR4 are the two main coreceptors essential for HIV entry. Therefore, these chemokine receptors have become important targets in the search for anti-HIV agents. Here, we describe the establishment of a novel CD4+ cell line, U87.CD4.CCR5.CXCR4, stably expressing both CCR5 and CXCR4 at the cell surface.
  
  
  RESULTS
  In these cells, intracellular calcium signalling through both receptors can be measured in a single experiment upon the sequential addition of CXCR4- and CCR5-directed chemokines. The U87.CD4.CCR5.CXCR4 cell line reliably supported HIV-1 infection of diverse laboratory-adapted strains and primary isolates with varying coreceptor usage (R5, X4 and R5/X4) and allows to investigate the antiviral efficacy of combined CCR5 and CXCR4 blockade. The antiviral effects recorded in these cells with the CCR5 antagonist SCH-C and the CXCR4 antagonist AMD3100 were similar to those noted in the single CCR5- or CXCR4-transfected U87.CD4 cells. Furthermore, the combination of both inhibitors blocked the infection of all evaluated HIV-1 strains and isolates.
  
  
  CONCLUSIONS
  Thus, the U87.CD4.CCR5.CXCR4 cell line should be useful in the evaluation of CCR5 and CXCR4 antagonists with therapeutic potential and combinations thereof.
authors.affiliation: Rega Institute for Medical Research, Katholieke Universiteit Leuven, B-3000 Leuven, Belgium. katrien.princen@rega.kuleuven.ac.be
authors.forename: Katrien
authors.initials: K
authors.lastname: Princen
authors.forename: Sigrid
authors.initials: S
authors.lastname: Hatse
authors.forename: Kurt
authors.initials: K
authors.lastname: Vermeire
authors.forename: Erik
authors.initials: E
authors.lastname: De Clercq
authors.forename: Dominique
authors.initials: D
authors.lastname: Schols
mesh_terms: D019380:Anti-HIV Agents / Q000494:pharmacology*; D001596:Benzylamines; D065100:CCR5 Receptor Antagonists; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects / Q000276:immunology* / Q000821:virology*; D020013:Calcium Signaling / Q000187:drug effects / Q000502:physiology; D002460:Cell Line; D045744:Cell Line, Tumor; D018925:Chemokines / Q000494:pharmacology; D000080027:Cyclams; D003497:Cyclic N-Oxides / Q000494:pharmacology; D006571:Heterocyclic Compounds / Q000494:pharmacology; D006801:Humans; D019169:Jurkat Cells; D010091:Oximes; D010880:Piperidines / Q000494:pharmacology; D011725:Pyridines / Q000494:pharmacology; D019713:Receptors, CCR5 / Q000502:physiology*; D019718:Receptors, CXCR4 / Q000037:antagonists & inhibitors / Q000502:physiology*
chemical_list: D019380:Anti-HIV Agents; D001596:Benzylamines; D065100:CCR5 Receptor Antagonists; D018925:Chemokines; D000080027:Cyclams; D003497:Cyclic N-Oxides; D006571:Heterocyclic Compounds; D010091:Oximes; D010880:Piperidines; D011725:Pyridines; D019713:Receptors, CCR5; D019718:Receptors, CXCR4; C438583:Ancriviroc; C088327:plerixafor