Prevention of in vitro neutrophil-endothelial attachment through shedding of L-selectin by nonsteroidal antiinflammatory drugs.
The activation of the endothelial cells by extravascular stimuli is the key event in the extravasation of circulating leukocytes to target tissues. L-selectin, a member of the selectin family, is constitutively expressed by white cells, and is the molecule involved in the initial binding of leukocytes to activated endothelium. After activation, leukocytes rapidly release L-selectin from the cell surface, suggesting that the functional activity of this molecule is controlled in large part by its appearance and disappearance from cell surface. We have studied in a neutrophil-activated endothelial cell binding assay, the effect of different antiinflammatory drugs (steroidal and nonsteroidal) in the L-selectin-mediated interaction of neutrophils with activated endothelial cells. Some nonsteroidal antiinflammatory drugs (NSAIDs), such as indomethacin, diclofenac, ketoprofen, and aspirin, but not steroids, strongly inhibited the neutrophil-endothelial cell attachment. Furthermore, we also investigated the underlying mechanism of this functional effect. The expression of L-selectin on the neutrophil surface rapidly decreased in the presence of different NSAIDs, in a dose- and time-dependent manner, whereas no changes in the expression of other adhesion molecules such as CD11a, CD11b, CD31, or ICAM-3 (CD50) were observed. Interestingly, studies in vivo on healthy volunteers treated with physiological doses of indomethacin showed a significant decrease of L-selectin neutrophil expression. Only diclofenac induced an upregulation of CD11b expression, suggesting an activating effect on neutrophils. No enzyme release was observed upon treatment of neutrophils with different NSAIDs, indicating a lack of degranulatory activity of NSAIDs, with the exception of diclofenac. The downregulation of L-selectin expression was due to the rapid cleavage and shedding of the membrane L-selectin, as determined by both immunoprecipitation from 125I-labeled neutrophils, and quantitative estimation in cell-free supernatants. These results suggest that NSAIDs exert a specific action on adhesion receptor expression in neutrophils, which might account, at least in part, for the antiinflammatory activities of NSAIDs.
Díaz-González
F
F
Section of Rheumatology, Hospital de la Princesa, Universidad Autónoma de Madrid, Spain.
González-Alvaro
I
I
Campanero
M R
MR
Mollinedo
F
F
del Pozo
M A
MA
Muñoz
C
C
Pivel
J P
JP
Sánchez-Madrid
F
F
D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology*; D015703:Antigens, CD / Q000096:biosynthesis; D001241:Aspirin / Q000494:pharmacology; D002448:Cell Adhesion / Q000187:drug effects*; D015815:Cell Adhesion Molecules / Q000378:metabolism*; D003594:Cytoplasmic Granules / Q000201:enzymology; D004008:Diclofenac / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D015536:Down-Regulation; D004730:Endothelium, Vascular / Q000502:physiology*; D004798:Enzymes / Q000378:metabolism; D006801:Humans; D007213:Indomethacin / Q000494:pharmacology; D007249:Inflammation / Q000209:etiology; D018799:Intercellular Adhesion Molecule-1 / Q000096:biosynthesis; D019041:L-Selectin; D009504:Neutrophils / Q000502:physiology*; D010894:Piroxicam / Q000494:pharmacology
D000894:Anti-Inflammatory Agents, Non-Steroidal; D015703:Antigens, CD; D015815:Cell Adhesion Molecules; D004798:Enzymes; D018799:Intercellular Adhesion Molecule-1; D019041:L-Selectin; D010894:Piroxicam; D004008:Diclofenac; D001241:Aspirin; D007213:Indomethacin