Early activation of MAP kinases by influenza A virus X-31 in murine macrophage cell lines

PLoS One. 2014 Aug 28;9(8):e105385. doi: 10.1371/journal.pone.0105385. eCollection 2014.

Abstract

Early molecular responses to Influenza A (FLUA) virus strain A/X-31 H3N2 in macrophages were explored using J774.A1 and RAW 264.7 murine cell lines. NF-kappa B (NFκB) was reported to be central to FLUA host-response in other cell types. Our data showed that FLUA activation of the classical NFκB dependent pathway in these macrophages was minimal. Regulator proteins, IkappaB-alpha and -beta (IκBα, IκBβ), showed limited degradation peaking at 2 h post FLUA exposure and p65 was not observed to translocate from the cytoplasm to the nucleus. Additionally, the non-canonical NFκB pathway was not activated in response to FLUA. The cells did display early increases in TNFα and other inflammatory cytokine and chemokine production. Mitogen activated phosphokinase (MAPK) signaling pathways are also reported to control production of inflammatory cytokines in response to FLUA. The activation of the MAPKs, cJun kinases 1 and 2 (JNK 1/2), extracellular regulated kinases 1 and 2 (ERK 1/2), and p38 were investigated in both cell lines between 0.25 and 3 h post-infection. Each of these kinases showed increased phosphorylation post FLUA exposure. JNK phosphorylation occurred early while p38 phosphorylation appeared later. Phosphorylation of ERK 1/2 occurred earlier in J774.A1 cells compared to RAW 264.7 cells. Inhibition of MAPK activation resulted in decreased production of most FLUA responsive cytokines and chemokines in these cells. The results suggest that in these monocytic cells the MAPK pathways are important in the early response to FLUA.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Cell Line
  • Enzyme Inhibitors / pharmacology
  • Influenza A virus*
  • JNK Mitogen-Activated Protein Kinases / metabolism*
  • Macrophages / drug effects
  • Macrophages / metabolism*
  • Macrophages / virology
  • Mice
  • NF-kappa B / metabolism
  • Phosphorylation / drug effects
  • Signal Transduction / drug effects
  • Signal Transduction / physiology*
  • p38 Mitogen-Activated Protein Kinases / metabolism*

Substances

  • Enzyme Inhibitors
  • NF-kappa B
  • JNK Mitogen-Activated Protein Kinases
  • p38 Mitogen-Activated Protein Kinases

Grants and funding

Research was supported by the Armed Forces Radiobiology Research Institute under project RAB3AM. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Federal Agencies reserve the right to review research publications and grant approval for release to the public domain. This approval has been received. The opinions expressed in this manuscript are those of the authors only and do not necessarily reflect those of AFRRI, the Uniformed Services University of the Health Sciences or the Department of Defense.