title: In vitro migratory responses of swine neutrophils to actinobacillus pleuropneumoniae.
abstract: Swine neutrophils were quantitatively examined for the direct and indirect migratory responses to Actinobacillus pleuropneumoniae (APP) in vitro and the effects of pseudorabies virus (PrV), frequently co-infecting with APP, were also observed. About 30% of swine neutrophils responded to viable APP, while 3.2% of the neutrophils responded to 0.1% casein which served as the control. The migration of APP was not affected by preincubation of neutrophils with PrV, which inhibited the random migration. When the random migration was normalized to 1, the chemotactic indices for APP, opsonized-APP and casein were 64, 70 and 8.5, respectively. Heat-killed APP or E. coli lipopolysaccharide stimulated the production of interleukin-8 activity by adherent peripheral blood mononuclear cells (PBMC). Preincubation of PBMC with PrV inhibited the production of neutrophil attractant activity when stimulated with heat-killed APP. The results suggested that the direct chemotaxis of neutrophils to viable APP might contribute to early infiltration in Actinobacillus pleuropneumonia, and that PrV might inhibit indirect recruitment of neutrophils to infected lungs by compromising the functions of PBMC.
authors.affiliation: Department of Veterinary Medicine, National Taiwan University, 142 Chou-San Road, Taipei 106, Taiwan.
authors.forename: F I
authors.initials: FI
authors.lastname: Wang
authors.forename: J W
authors.initials: JW
authors.lastname: Yang
authors.forename: S Y
authors.initials: SY
authors.lastname: Hung
authors.forename: I J
authors.initials: IJ
authors.lastname: Pan
mesh_terms: D016977:Actinobacillus pleuropneumoniae / Q000276:immunology*; D000818:Animals; D002364:Caseins / Q000494:pharmacology; D002448:Cell Adhesion; D002634:Chemotaxis, Leukocyte; D017077:Culture Media, Conditioned; D011558:Herpesvirus 1, Suid / Q000276:immunology / Q000502:physiology; D016209:Interleukin-8 / Q000096:biosynthesis; D007700:Kinetics; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D009504:Neutrophils / Q000276:immunology*; D013552:Swine / Q000276:immunology*; D013553:Swine Diseases / Q000276:immunology
chemical_list: D002364:Caseins; D017077:Culture Media, Conditioned; D016209:Interleukin-8; D009240:N-Formylmethionine Leucyl-Phenylalanine