TY - JOUR
T1 - The acute-phase response and serum amyloid A inhibit the inflammatory response to Acinetobacter baumannii Pneumonia
AU - Renckens, Rosemarijn
AU - Roelofs, Joris J. T. H.
AU - Knapp, Sylvia
AU - de Vos, Alex F.
AU - Florquin, Sandrine
AU - van der Poll, Tom
PY - 2006
Y1 - 2006
N2 - BACKGROUND: Acinetobacter baumannii is an emerging pathogen in nosocomial pneumonia. Trauma and postsurgical patients display a profound acute-phase protein response and are susceptible to pneumonia. METHODS: To study the way in which the acute-phase response induced by sterile tissue injury influences pulmonary host defense, mice were injected subcutaneously with turpentine or saline in both hind limbs either 2 or 5 days before intranasal inoculation with A. baumannii. RESULTS: Turpentine-injected mice demonstrated strong increases in levels of the acute-phase proteins serum amyloid A (SAA) and serum amyloid P. The inflammatory response to A. baumannii was significantly impaired in turpentine-injected mice, as shown by decreased local cytokine and chemokine levels, reduced neutrophil influx and lung myeloperoxidase activity, less pulmonary inflammation on histological examination, and lower total protein levels in their bronchoalveolar lavage fluid, which was associated with reduced bacterial clearance of A. baumannii. The late acute-phase protein response still caused lower pulmonary cytokine levels and neutrophil recruitment. Furthermore, previous injection of SAA, a major acute-phase protein, also reduced inflammatory responses to A. baumannii pneumonia. CONCLUSIONS: These data suggest that the acute-phase response and SAA inhibit the local inflammatory response to A. baumannii pneumonia, which may facilitate bacterial outgrowth
AB - BACKGROUND: Acinetobacter baumannii is an emerging pathogen in nosocomial pneumonia. Trauma and postsurgical patients display a profound acute-phase protein response and are susceptible to pneumonia. METHODS: To study the way in which the acute-phase response induced by sterile tissue injury influences pulmonary host defense, mice were injected subcutaneously with turpentine or saline in both hind limbs either 2 or 5 days before intranasal inoculation with A. baumannii. RESULTS: Turpentine-injected mice demonstrated strong increases in levels of the acute-phase proteins serum amyloid A (SAA) and serum amyloid P. The inflammatory response to A. baumannii was significantly impaired in turpentine-injected mice, as shown by decreased local cytokine and chemokine levels, reduced neutrophil influx and lung myeloperoxidase activity, less pulmonary inflammation on histological examination, and lower total protein levels in their bronchoalveolar lavage fluid, which was associated with reduced bacterial clearance of A. baumannii. The late acute-phase protein response still caused lower pulmonary cytokine levels and neutrophil recruitment. Furthermore, previous injection of SAA, a major acute-phase protein, also reduced inflammatory responses to A. baumannii pneumonia. CONCLUSIONS: These data suggest that the acute-phase response and SAA inhibit the local inflammatory response to A. baumannii pneumonia, which may facilitate bacterial outgrowth
U2 - https://doi.org/10.1086/498876
DO - https://doi.org/10.1086/498876
M3 - Article
C2 - 16362882
SN - 0022-1899
VL - 193
SP - 187
EP - 195
JO - Journal of infectious diseases
JF - Journal of infectious diseases
IS - 2
ER -