ABSTRACT
The accumulation of eosinophils in tissues is dependent on their removal from the axial stream to roll along blood vessels and then to migrate through endothelial junctions into tissues. The capture of leukocytes from the axial stream is mediated by selectins. P-selectin in particular has been shown to mediate the shear resistant adhesion and rolling of neutrophils and to allow the more stable integrin intercellular adhesion molecule-1-dependent adhesion reactions to take place that appear necessary for transmigration. P-selectin was extracted from human platelets, purified by affinity chromatography, and then for assay, either immobilized onto microtiter wells, or used in the fluid phase after Triton X-100 removal by Extractigel-D. Eosinophils were purified from normal human blood by dextran sedimentation and discontinuous, slightly hypertonic metrizamide gradients. Eosinophil cationic protein release was determined as a measure of eosinophil degranulation. Purified human eosinophils adhered weakly to microtiter plates coated with fetal calf serum.
