title: Neutrophil adhesion to 24-hour IL-1-stimulated endothelial cells under flow conditions.
abstract: In this study, we examine neutrophil adhesion under flow conditions to cultured HUVEC stimulated for 4 or 24 h with IL-1. Interactions are measured using videomicroscopy and a parallel-plate flow system which is capable of distinguishing primary adhesion and rolling from secondary (firm) adhesion. We find that after 24 h, E-selectin does not contribute to primary adhesion, in contrast to a significant contribution after 4 h. Endothelial cell P-selectin does not contribute at either time point. Blocking or removing L-selectin from the neutrophil surface decreases adhesion 50 to 70% at either time point, and neuraminidase treatment of neutrophils decreases adhesion by 85%. These results suggest that after a 24-h stimulation, primary adhesion depends on a distinct selectin-like interaction in which a HUVEC receptor binds carbohydrates on neutrophil glycoproteins, including L-selectin. We also find that secondary adhesion in this system can be inhibited 90% with Ab blockade of CD18/ICAM-1 interactions after a 24-h stimulation, and that a combination of IL-1 and IL-4 selectively down-regulates the pathway for primary adhesion at 24 h. These results demonstrate that neutrophils adhere using different receptor pathways following 4- and 24-h stimulations, and provide experimental data characterizing some properties of the receptors involved. One of the pathways that is evident at 24 h appears to be a novel selectin-like interaction.
authors: Cox Laboratory for Biomedical Engineering, Institute of Biosciences and Bioengineering, Rice University, Houston, TX 77251, USA.
authors: D A
authors: DA
authors: Jones
authors: C W
authors: CW
authors: Smith
authors: L J
authors: LJ
authors: Picker
authors: L V
authors: LV
authors: McIntire
mesh_terms: D001783:Blood Flow Velocity; D002448:Cell Adhesion / Q000187:drug effects / Q000276:immunology; D015536:Down-Regulation / Q000187:drug effects / Q000276:immunology; D004338:Drug Combinations; D004730:Endothelium, Vascular / Q000187:drug effects* / Q000502:physiology*; D006801:Humans; D007375:Interleukin-1 / Q000494:pharmacology*; D015847:Interleukin-4 / Q000494:pharmacology; D009504:Neutrophils / Q000187:drug effects* / Q000502:physiology*; D013997:Time Factors; D014470:Umbilical Cord / Q000166:cytology
chemical_list: D004338:Drug Combinations; D007375:Interleukin-1; D015847:Interleukin-4