title: [Is platelet protein S different from plasma protein S in human being?].
abstract: Platelet suspension was obtained from normal platelet rich plasma (PRP) by the gel filtration method using Sepharose 2B and platelet pellet was prepared from the platelet suspension after centrifugation. A platelet preparation was prepared from the solubilized platelet pellet. Purified protein S was obtained from plasma and platelet preparation using immuno-affinity column chromatography. Total antigen of protein S was measured by enzyme immunoassay and activity of protein S was measured as a cofactor of activated protein C. The ratio of purified protein S activity to total antigen in normal plasma and platelet was 2.3 and 2.1, respectively. According to immunoblot and crossed immunoelectrophoresis studies, the molecular weight of platelet protein S was different from that of plasma protein S. Localization of protein S in platelet alpha-granules was demonstrated by immunoelectronmicroscopy.
authors.affiliation: 2nd Department of Internal Medicine, Yamanashi Medical College.
authors.forename: H
authors.initials: H
authors.lastname: Ozawa
authors.forename: I
authors.initials: I
authors.lastname: Kobayashi
authors.forename: M
authors.initials: M
authors.lastname: Marumo
mesh_terms: D001792:Blood Platelets / Q000378:metabolism*; D006023:Glycoproteins / Q000097:blood* / Q000302:isolation & purification; D006801:Humans; D015151:Immunoblotting; D007122:Immunoelectrophoresis; D008970:Molecular Weight; D010949:Plasma / Q000378:metabolism*; D017293:Protein S
chemical_list: D006023:Glycoproteins; D017293:Protein S