title: Thrombospondin measured in whole blood--an indicator of platelet activation.
abstract: Abnormal platelet activation may be involved in prethrombotic states and lead to thromboembolism. When platelets become activated, they release thrombospondin (TSP) from their alpha-granules which binds mainly to the surface of activated platelets, platelet-derived microparticles and other blood cells. To determine bound as well as free TSP in a single assay, we developed an indirect ELISA to measure TSP in fixed whole blood. The intra-assay variance was less than 5% and 97% of purified standard TSP, added to whole blood samples, was recovered with the ELISA. Blood collected with a 20G needle into a syringe resulted in lower "whole blood TSP' values than blood collected with the Vacutainer system. Whole blood TSP levels were measured in 66 healthy blood donors (20F, 46M) aged 25-75 years. The mean whole blood TSP concentration was 33 +/- 19 ng/ml. No significant difference in whole blood TSP was found between healthy females and males (35 +/- 23 ng/ml vs. 33 +/- 17 ng/ml).
authors: University of Muenster, Department of Internal Medicine, Germany.
authors: B
authors: B
authors: Kehrel
authors: E
authors: E
authors: Flicker
authors: B
authors: B
authors: Wigbels
authors: M
authors: M
authors: Osterfeld
authors: J
authors: J
authors: van de Loo
authors: E F
authors: EF
authors: Lüscher
mesh_terms: D000328:Adult; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D008297:Male; D008562:Membrane Glycoproteins / Q000097:blood*; D015539:Platelet Activation; D010979:Platelet Function Tests / Q000379:methods; D019699:Thrombospondins
chemical_list: D008562:Membrane Glycoproteins; D019699:Thrombospondins