Live Staphylococcus aureus and bacterial soluble factors induce different transcriptional responses in human airway cells

Physiol Genomics. 2005 Feb 10;20(3):244-55. doi: 10.1152/physiolgenomics.00135.2004. Epub 2004 Dec 14.

Abstract

To characterize the response of respiratory epithelium to infection by Staphylococcus aureus (S. aureus), human airway cells were incubated for 1 to 24 h with a supernatant of a S. aureus culture (bacterial supernatant), then profiled with a pangenomic DNA microarray. Because an upregulation of many genes was noticed around 3 h, three independent approaches were then used to characterize the host response to a 3-h contact either with bacterial supernatant or with live bacteria: 1) a DNA microarray containing 4,200 sequence-verified probes, 2) a semiquantitative RT-PCR with a set of 537 pairs of validated primers, or 3) ELISA assay of IL-8, IL-6, TNFalpha, and PGE(2). Among others, Fos, Jun, and EGR-1 were upregulated by the bacterial supernatant and by live bacteria. Increased expression of bhlhb2 and Mig-6, promoter regions which harbor HIF responding elements, was explained by an increased expression of the HIF-1alpha protein. Activation of the inducible form of cyclooxygenase, COX-2, and of the interleukins IL-1, IL-6, and IL-8, as well as of the NF-kappaB pathway, was observed preferentially in cells in contact with bacterial supernatant. Early infection was characterized by an upregulation of anti-apoptotic genes and a downregulation of pro-apoptotic genes. This correlated with a necrotic, rather than apoptotic cell death. Overall, this first global description of an airway epithelial infection by S. aureus demonstrates a larger global response to bacterial supernatant (in term of altered genes and variation factors) than to exponentially growing live bacteria.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Culture Techniques
  • Cell Extracts / pharmacology
  • Computational Biology
  • DNA, Complementary / genetics
  • Humans
  • Oligonucleotide Array Sequence Analysis*
  • RNA / genetics
  • Respiratory Mucosa / drug effects
  • Respiratory Mucosa / microbiology*
  • Respiratory Mucosa / physiology*
  • Staphylococcus aureus / physiology*
  • Transcription, Genetic* / drug effects

Substances

  • Cell Extracts
  • DNA, Complementary
  • RNA