Mechanism of factor VIII inactivation by human antibodies. III. Proteolytic cleavage of factor VIII:C and C antigen by thrombin.
نویسندگان
چکیده
Thrombin activation of factor VIII results in a marked, but transient, increase in factor VIII procoagulant activity. This proteolytic process has been examined by immobilizing factor VIII in a solid phase system using mouse monoclonal antibody specific for the factor VIII related antigen. These studies demonstrate that thrombin activation is the result of proteolytic cleavage from the factor VIII:C protein of a peptide fragment which contains both the factor VIII:C procoagulant and VIII:C antigen sites recognized by human antibodies.
منابع مشابه
Proteolytic inactivation of human factor VIII procoagulant protein by activated human protein C and its analogy with factor V.
Purified human factor VIII procoagulant protein (VIII:C) was treated with purified human activated protein C (APC) and the loss of VIII:C activity correlated with proteolysis of the VIII:C polypeptides. APC proteolyzed all VIII:C polypeptides with mol wt = 92,000 or greater, but not the doublet at mol wt = 79-80,000. These results and our previous thrombin activation studies of purified VIII:C,...
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ورودعنوان ژورنال:
- Annals of clinical and laboratory science
دوره 15 6 شماره
صفحات -
تاریخ انتشار 1985