Canine neutrophil margination mediated by lectin adhesion molecule-1 in vitro.
The contributions of the canine neutrophil lectin adhesion molecule-1 (LECAM-1) (canine homologue of the murine MEL-14 Ag) in neutrophil-endothelial cell adhesion and transendothelial migration were studied using anti-LECAM-1 mAb, CL2/6, and SL1 under static conditions and at wall shear stresses of up to 1.85 dynes/cm2 (dpc). Both mAb were found to inhibit attachment of neutrophils to cytokine-stimulated canine jugular vein endothelium. The inhibitory effects of the anti-LECAM-1 mAb were more evident at a wall shear stress of 1.85 dpc (greater than 50%) than at 0.23 dpc or under static conditions (approximately 30%). In contrast the anti-CD18 mAb, R15.7, exhibited higher inhibitory ability at the lower shear stress and under static conditions with marginal inhibition of adhesion at 1.85 dpc. Anti-LECAM-1 and anti-CD18 mAb showed additive inhibitory effects at the lower wall shear stress and under static conditions. Chemotactic stimulation of the neutrophils caused rapid down-regulation of LECAM-1 from the neutrophil surface and reduced adhesion by 60% at a wall shear stress of 1.85 dpc. This inhibition was not additive to anti-LECAM-1 mAb. Pretreatment with CL2/6 or SL1 did not affect trans-endothelial migration of adherent neutrophils under any experimental conditions tested. Anti-CD18 mAb, however, blocked transendothelial migration by 98% and 56% under static condition and at a wall shear stress of 0.23 dpc, respectively. The results in this report indicate that canine LECAM-1 is involved in the initial adhesion of unstimulated neutrophils to cytokine-stimulated endothelial cells under flow, but in contrast to CD18-integrins, plays no role in the transendothelial migration.
Abbassi
O
O
Biomedical Engineering Laboratory, Rice University, Houston, TX 77251.
Lane
C L
CL
Krater
S
S
Kishimoto
T K
TK
Anderson
D C
DC
McIntire
L V
LV
Smith
C W
CW
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D015703:Antigens, CD / Q000502:physiology; D018821:CD18 Antigens; D002448:Cell Adhesion; D015815:Cell Adhesion Molecules / Q000502:physiology*; D004285:Dogs; D019040:E-Selectin; D004730:Endothelium, Vascular / Q000502:physiology; D019041:L-Selectin; D009504:Neutrophils / Q000502:physiology*; D015054:Zymosan / Q000494:pharmacology
D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D018821:CD18 Antigens; D015815:Cell Adhesion Molecules; D019040:E-Selectin; D019041:L-Selectin; D015054:Zymosan