title: Channel catfish, Ictalurus punctatus rafinesque, neutrophil adhesion to selected extracellular matrix proteins, lipopolysaccharide, and catfish serum.
abstract: Adhesion of leukocytes to endothelium and extracellular matrix proteins is an important step in the inflammatory process. Therefore, the adhesion of channel catfish neutrophils to a surface coated with extracellular matrix proteins, LPS, and non-immune catfish serum was evaluated. Stimulation of neutrophils with phorbol dibutyrate (PDBU) resulted in at least two-fold increases in cellular adhesion to all substrates tested except laminin. When EDTA was included during or after PDBU stimulation, neutrophil adhesion to fibrinogen and LPS coated surfaces was reduced to the level of unstimulated neutrophils or to 50-60% of that for stimulated neutrophils. Similarly, EDTA and Ca2+/Mg2+ deficient medium reduced homotypic aggregation of PDBU stimulated neutrophils to background levels. Adhesion of stimulated neutrophils to fibrinogen coated surfaces was inhibited 44, 33, and 50% when soluble fibrinogen, fibronectin, and serum, respectively, were used to block the adhesion assay. The tripeptide integrin adhesion recognition sequence, Arg-Gly-Asp (RGD), caused 83% reduction and the fibrinogen-binding inhibitor protein caused 10% reduction in binding of stimulated neutrophils to fibrinogen coated surfaces. Two hexapeptides tested did not reduce neutrophil adhesion to fibrinogen. The binding of channel catfish neutrophils to the matrices used in the present study is suggestive that integrin mediated adhesion occurs during biological and pathological processes of teleosts.
authors.affiliation: College of Veterinary Medicine, Mississippi State University, MS 39762-9825, USA.
authors.forename: A J
authors.initials: AJ
authors.lastname: Alnsworth
authors.forename: Q
authors.initials: Q
authors.lastname: Ye
authors.forename: L
authors.initials: L
authors.lastname: Xue
authors.forename: P
authors.initials: P
authors.lastname: Hébert
mesh_terms: D000818:Animals; D001667:Binding, Competitive; D001769:Blood / Q000378:metabolism; D002118:Calcium / Q000378:metabolism; D002448:Cell Adhesion / Q000187:drug effects / Q000502:physiology*; D016326:Extracellular Matrix Proteins / Q000378:metabolism; D007059:Ictaluridae / Q000502:physiology*; D008070:Lipopolysaccharides / Q000378:metabolism; D008274:Magnesium / Q000378:metabolism; D018375:Neutrophil Activation; D009504:Neutrophils / Q000187:drug effects / Q000502:physiology*; D009842:Oligopeptides / Q000494:pharmacology; D015240:Phorbol 12,13-Dibutyrate / Q000494:pharmacology
chemical_list: D016326:Extracellular Matrix Proteins; D008070:Lipopolysaccharides; D009842:Oligopeptides; D015240:Phorbol 12,13-Dibutyrate; D008274:Magnesium; D002118:Calcium