title: The platelet activating factor receptor is not required for exacerbation of bacterial pneumonia following influenza.
abstract: Pneumonia caused by Streptococcus pneumoniae is a significant cause of morbidity and mortality during influenza virus epidemics. We had previously advanced the hypothesis that interactions of pneumococcus with the receptor for platelet activating factor (PAFR) in the lung were facilitated by antecedent influenza virus infection and play a major role in the pathogenesis of bacterial superinfections. Although influenza enhanced the adherence of pneumococci to respiratory epithelial cells in vitro, chemical or antibody-mediated blockade of the PAFR did not affect adherence. In agreement with these data, mice lacking PAFR had similar bacterial loads within the lung compartment when compared to heterozygous littermates and were not protected from secondary pneumococcal pneumonia after influenza. Lack of support for this hypothesis and the observation of enhanced inflammation during secondary pneumococcal pneumonia in mice lacking PAFR may moderate enthusiasm for treatment strategies targeting the interaction of bacteria with PAFR.
authors.affiliation: Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, Tennessee 38105-2794, USA. jon.mccullers@stjude.org
authors.forename: Jonathan A
authors.initials: JA
authors.lastname: McCullers
authors.forename: Amy R
authors.initials: AR
authors.lastname: Iverson
authors.forename: Raelene
authors.initials: R
authors.lastname: McKeon
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Murray
mesh_terms: D000818:Animals; D001422:Bacterial Adhesion; D004195:Disease Models, Animal; D005260:Female; D053118:Influenza A Virus, H1N1 Subtype / Q000472:pathogenicity*; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D009976:Orthomyxoviridae Infections / Q000150:complications*; D010980:Platelet Membrane Glycoproteins / Q000235:genetics / Q000502:physiology*; D011018:Pneumonia, Pneumococcal / Q000150:complications* / Q000821:virology; D043562:Receptors, G-Protein-Coupled / Q000235:genetics / Q000502:physiology*; D013296:Streptococcus pneumoniae / Q000472:pathogenicity*; D015163:Superinfection
chemical_list: D010980:Platelet Membrane Glycoproteins; D043562:Receptors, G-Protein-Coupled; C039351:platelet activating factor receptor