Airway interleukin-8 in elderly patients with bacterial lower respiratory tract infections.
We investigated the interleukin-8 (IL-8) levels and neutrophil numbers in the sputum of 9 elderly patients with lower respiratory tract infections, including Pseudomonas aeruginosa infection, before and after treatment with various antimicrobial agents. The IL-8 levels in sputum supernatants and the neutrophil numbers in sputum smears from 9 patients decreased significantly after the elimination of the causative respiratory pathogens. We also demonstrated that human recombinant IL-8 at a range of 6.25-25 ng/ml significantly enhanced opsonophagocytic killing of P. aeruginosa immunotype-1 strain by human neutrophils in the presence of a serotype-specific anti-lipopolysaccharide monoclonal antibody and fresh normal human serum. These data suggest that the level of IL-8 production in the airways of patients with lower respiratory tract infections is dependent on bacterial densities, and indicate the important role of IL-8 not only in neutrophil migration but also in opsonophagocytic killing of bacteria in the lower respiratory tract.
Ponglertnapagorn
P
P
Department of Internal Medicine, Nagasaki University, Japan.
Oishi
K
K
Iwagaki
A
A
Sonoda
F
F
Watanabe
K
K
Nagatake
T
T
Matsushima
K
K
Matsumoto
K
K
D000368:Aged; D001424:Bacterial Infections / Q000276:immunology*; D001987:Bronchiectasis / Q000276:immunology*; D001991:Bronchitis / Q000276:immunology*; D001996:Bronchopneumonia / Q000276:immunology*; D005260:Female; D006801:Humans; D016209:Interleukin-8 / Q000276:immunology* / Q000494:pharmacology; D008297:Male; D008875:Middle Aged; D018410:Pneumonia, Bacterial / Q000276:immunology; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D011993:Recombinant Fusion Proteins / Q000494:pharmacology; D012141:Respiratory Tract Infections / Q000276:immunology; D012709:Serum Albumin; D013183:Sputum / Q000276:immunology
D016209:Interleukin-8; D011993:Recombinant Fusion Proteins; D012709:Serum Albumin