title: Human platelet basic protein. Its relation to low affinity platelet factor 4 and beta-thromboglobulin.
abstract: Human beta-thromboglobulin, low affinity platelet factor 4 and platelet basic protein have been purified to homogeneity from the material released by thrombin-stimulated platelets. Purification steps included isoelectric focusing and heparin-agarose chromatography. Antibodies against each of these proteins have been raised in rabbits. Antigenic identity of the proteins has been demonstrated in radioimmunoassay using 125I-labelled platelet basic protein or 125I-labelled low affinity platelet factor 4 and a variety of antibodies. The molecular weight of platelet basic protein estimated by gel filtration in 6 M guanidine hydrochloride using Sepharose 6B corresponded to approx. 10 000 daltons, slightly higher than that of beta-thromboglobulin (8851 daltons) and low affinity platelet factor 4 (9278 daltons). These findings raise the possibility that the formation of low affinity platelet factor 4 beta-thromboglobulin may be a consequence of the action of proteolytic enzymes on platelet basic protein.
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000918:Antibody Specificity; D001609:Beta-Globulins / Q000276:immunology*; D001779:Blood Coagulation Factors / Q000276:immunology*; D001792:Blood Platelets / Q000276:immunology*; D001798:Blood Proteins / Q000276:immunology*; D002850:Chromatography, Gel; D000939:Epitopes / Q000276:immunology*; D006146:Guanidines; D006801:Humans; D008970:Molecular Weight; D010455:Peptides; D011817:Rabbits / Q000276:immunology; D011863:Radioimmunoassay; D001620:beta-Thromboglobulin / Q000276:immunology*
chemical_list: D001609:Beta-Globulins; D001779:Blood Coagulation Factors; D001798:Blood Proteins; D000939:Epitopes; D006146:Guanidines; D010455:Peptides; D001620:beta-Thromboglobulin; C009862:connective tissue-activating peptide; C018329:low affinity platelet factor 4