Studies on the Liberation of β‐Thromboglobulin from Human Platelets in Vitro

S ummary . A platelet specific protein, β‐thromboglobulin, is liberated during the preparation of platelet poor plasma. Using combinations of different anticoagulant and anti‐platelet compounds, this release can be significantly reduced. The best results were obtained when native blood was collected as soon as possible into a mixture of EDTA, prostaglandin E 1 and theophylline and maintained and processed at a temperature between 0 and 4°C. These technical innovations have permitted the use of a radioimmunoassay for β‐thromboglobulin on plasma samples in clinical practice.