Studies on Human Platelet Protease Activity
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SOLUBILIZED PROTEIN DERIVED FROM HUMAN PLATELETS WAS FRACTIONATED BY DEAE CELLULOSE COLUMN CHROMATOGRAPHY AND ANALYZED FOR PROTEASE ACTIVITY USING THREE SUBSTRATES: denatured bovine hemoglobin, alpha casein, and purified plasminogen-free human fibrinogen. A protein fraction was found with proteolytic activity which was heat labile and not attributable to plasmin. The activity was not potentiated by cysteine or inhibited by iodoacetamide. Studies of pH optima indicated a broad range of enzyme activity with peaks in both the acid and alkaline region. Cathepsin A activity was detected in the platelet protease fraction by hydrolysis of the synthetic substrate N-carbobenzoxy-alpha-L-glutamyl-L-tyrosine. Similar proteolytic activity was found when the proteins derived from isolated platelet granules were examined. The results indicate that human platelets possess potent intracellular proteolytic enzymes. The relationship of this proteolytic activity to the hemostatic process is discussed.
Plow E J Clin Invest. 1982; 69(3):564-72.
PMID: 6916769 PMC: 371012. DOI: 10.1172/jci110482.
Platelets in the synovial fluid of patients with rheumatoid arthritis.
Farr M, Wainwright A, Salmon M, Hollywell C, Bacon P Rheumatol Int. 1984; 4(1):13-7.
PMID: 6718950 DOI: 10.1007/BF00683878.
[Studies of the dipeptidase activity in thrombocytes].
KOSSMANN K, Kuhner U Klin Wochenschr. 1970; 48(5):297-300.
PMID: 5523223 DOI: 10.1007/BF01486439.
Enzyme system in rat leucocyte granules which degrades insoluble collagen.
Anderson A Ann Rheum Dis. 1971; 30(3):299-302.
PMID: 5090246 PMC: 1005772. DOI: 10.1136/ard.30.3.299.
Platelet interaction with bacteria. II. Fate of the bacteria.
Clawson C, White J Am J Pathol. 1971; 65(2):381-97.
PMID: 5002629 PMC: 2047443.