title: Mouse macrophage innate immune response to Chikungunya virus infection.
abstract: BACKGROUND
  Infection with Chikungunya alphavirus (CHIKV) can cause severe arthralgia and chronic arthritis in humans with persistence of the virus in perivascular macrophages of the synovial membrane by mechanisms largely ill-characterized.
  
  
  RESULTS
  We herein analysed the innate immune response (cytokine and programmed cell death) of RAW264.7 mouse macrophages following CHIKV infection. We found that the infection was restrained to a small percentage of cells and was not associated with a robust type I IFN innate immune response (IFN-α4 and ISG56). TNF-α, IL-6 and GM-CSF expression were upregulated while IFN-γ, IL-1α, IL-2, IL-4, IL-5, IL-10 or IL-17 expression could not be evidenced prior to and after CHIKV exposure. Although CHIKV is known to drive apoptosis in many cell types, we found no canonical signs of programmed cell death (cleaved caspase-3, -9) in infected RAW264.7 cells.
  
  
  CONCLUSIONS
  These data argue for the capacity of CHIKV to infect and drive a specific innate immune response in RAW264.7 macrophage cell which seems to be polarized to assist viral persistence through the control of apoptosis and IFN signalling.
authors.affiliation: GRI/IRG (EA4517), Immunopathology and infectious diseases research grouping, University of La Reunion, CHU and CYROI research centres, St-Denis, La Reunion, France.
authors.forename: Shiril
authors.initials: S
authors.lastname: Kumar
authors.forename: Marie-Christine
authors.initials: MC
authors.lastname: Jaffar-Bandjee
authors.forename: Claude
authors.initials: C
authors.lastname: Giry
authors.forename: Léa
authors.initials: L
authors.lastname: Connen de Kerillis
authors.forename: Andres
authors.initials: A
authors.lastname: Merits
authors.forename: Philippe
authors.initials: P
authors.lastname: Gasque
authors.forename: Jean-Jacques
authors.initials: JJ
authors.lastname: Hoarau
mesh_terms: D000818:Animals; D017209:Apoptosis; D002460:Cell Line; D002646:Chikungunya virus / Q000276:immunology*; D016207:Cytokines / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D020869:Gene Expression Profiling; D007113:Immunity, Innate; D008264:Macrophages / Q000276:immunology* / Q000821:virology*; D051379:Mice; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D016207:Cytokines