Proteomic analysis of platelet α‐granules using mass spectrometry

摘要: Summary. Background: Platelets have three major types of secretory organelles: lysosomes, dense granules, and α-granules. α-Granules contain several adhesive proteins involved in hemostasis, as well glycoproteins inflammation, wound healing, cell–matrix interactions. This article represents the first effort to define platelet α-granule proteome using mass spectrometry (MS). Methods: We prepared a subcellular fraction enriched intact α-granules from human platelets sucrose gradient ultracentrifugation. α-Granule were separated identified sodium dodecylsulfate polyacrylamide gel electrophoresis liquid chromatography–tandem MS. Results: In α-granules, we 284 non-redundant proteins, 44 which appear be new on basis literature review. Immunoelectron microscopy confirmed presence Scamp2, APLP2, ESAM LAMA5 for time. We 65% same that detected releasate (J. A. Coppinger et al. [Blood 2004;103: 2096–104]) additional soluble membrane proteins. Our method provides suitable tool analyzing granule patients with storage pool deficiencies.