title: Inhibition of polymorphonuclear leukocyte capping by a chemotactic factor.
abstract: Incubation of human polymorphonuclear leukocytes with colchicine and fluorescein-concanavalin A leads to the formation of a polarized cap of fluorescence not seen if cells are incubated with fluorescein-Con A along. When cells are preincubated with a chemotactic factor before colchicine treatment, the capping is inhibited in a dose-related manner. Studies with alpha-methylmannoside indicate that the caps represent extracellular fluorescein-Con A and are not areas of Con A internalization. Experiments utilizing an irreversible inhibitor of serine esterases suggest that a chemotactic factor-activated enzyme is involved in the inhibition of cap formation in the human neutrophil.
mesh_terms: D002462:Cell Membrane / Q000201:enzymology / Q000276:immunology; D002634:Chemotaxis, Leukocyte / Q000187:drug effects; D003078:Colchicine / Q000494:pharmacology; D003208:Concanavalin A / Q000494:pharmacology; D004950:Esterases / Q000037:antagonists & inhibitors; D005452:Fluoresceins / Q000494:pharmacology; D005455:Fluorescent Antibody Technique; D006801:Humans; D066298:In Vitro Techniques; D007531:Isoflurophate / Q000494:pharmacology; D008297:Male; D008870:Microtubules / Q000276:immunology; D009504:Neutrophils / Q000201:enzymology / Q000276:immunology*
chemical_list: D005452:Fluoresceins; D003208:Concanavalin A; D007531:Isoflurophate; D004950:Esterases; D003078:Colchicine