THE ENDOGENOUS LECTIN OF HUMAN-PLATELETS IS AN ALPHA-GRANULE COMPONENT

  • 1 January 1981
    • journal article
    • research article
    • Vol. 58  (1) , 153-157
Abstract
Platelets from patients with several bleeding disorders (congenital afibrinogenemia, Glanzmann''s thrombasthenia, gray platelet syndrome and Hermansky-Pudlak syndrome) were evaluated for both platelet-bound and platelet-free hemagglutination activities. Thrombin and A23187 activated afibrinogenemic, Hermansky-Pudlak and thrombasthenic platelets had normal platelet-bound hemagglutination activity. Gray platelets activated by the same agents had deficient platelet-bound hemagglutination activity. In contrast, thrombin-activated afibrinogenemic, gray and thrombasthenic platelets lacked platelet-free hemagglutination activity. Only thrombin-activated Hermansky-Pudlak platelets had a normal level of platelet-free hemagglutination activity. The .alpha.-granules apparently are the origin of the enhanced hemagglutination activity. The insufficiency of the platelet-bound agglutinin may be the cause of the inability of gray platelets to aggregate normally in response to thrombin.