title: Role of CD 11/CD 18 in neutrophil emigration during acute and recurrent Pseudomonas aeruginosa-induced pneumonia in rabbits.
abstract: This study examined CD11/CD18-mediated adhesion in neutrophil emigration during acute and recurrent Pseudomonas aeruginosa-induced pneumonia. Neutrophil emigration during acute pneumonia was studied in anti-CD18 antibody or murine-IgG-pretreated rabbits 4 hours after intrabronchial instillation of P. aeruginosa. To examine emigration in recurrent pneumonias, rabbits given P. aeruginosa on day 0 received anti-CD18 antibody or IgG on day 7. A second instillate was placed either at the initial site or in a separate lobe, and emigration into alveolar spaces was quantitated morphometrically after 4 hours. The results show that CD11/CD18 was required for neutrophil emigration in acute pneumonias and in recurrent pneumonias that occurred at a site distant from the initial infection. However, when the recurrent pneumonia occurred in the previously inflamed site, CD11/CD18 was not required. When the same number of organisms were instilled on days 0 and 7, emigration was reduced to 15 to 20 percent of the number that migrated initially and only CD18-independent adhesion pathways were used. Increasing the concentration of organisms threefold increased emigration through both CD18-dependent and CD18-independent pathways. These data indicate that P. aeruginosa induces CD11/CD18-dependent emigration during acute pneumonia and recurrent pneumonia at previously uninflamed sites. However, adhesion pathways are altered in regions of chronic inflammation, and a greater proportion of neutrophil emigration occurs through CD11/CD18-independent pathways.
authors.affiliation: Herman B. Wells Center for Pediatric Research, Department of Pediatrics, Indiana University, Indianapolis, USA.
authors.forename: T
authors.initials: T
authors.lastname: Kumasaka
authors.forename: N A
authors.initials: NA
authors.lastname: Doyle
authors.forename: W M
authors.initials: WM
authors.lastname: Quinlan
authors.forename: L
authors.initials: L
authors.lastname: Graham
authors.forename: C M
authors.initials: CM
authors.lastname: Doerschuk
mesh_terms: D000208:Acute Disease; D000818:Animals; D018845:CD11 Antigens / Q000502:physiology*; D018821:CD18 Antigens / Q000502:physiology*; D002634:Chemotaxis, Leukocyte / Q000276:immunology*; D009504:Neutrophils / Q000276:immunology*; D018410:Pneumonia, Bacterial / Q000209:etiology / Q000276:immunology* / Q000473:pathology*; D011550:Pseudomonas aeruginosa; D011817:Rabbits; D012008:Recurrence
chemical_list: D018845:CD11 Antigens; D018821:CD18 Antigens