Protein disulphide isomerase (PDI) activity is released by activated platelets. In this study, PDI was purified from platelets and found to have an apparent mass, pI and N-terminal sequence similar to those for other human PDIs. Rabbit antibodies were generated and used to establish that, on activation, platelets release a protein immunologically identical to PDI in platelets. Approximately 10% of total platelet PDI was released by thrombin and 20% by calcium ionophore. The antibody was used to demonstrate PDI on the external surface of platelets by electron microscopy. Flow cytometry was used to demonstrate that upon activation of platelets with ionophore PDI was released by vesiculation. Since platelets are present and become activated at sites of vascular injury, platelet PDI may play a role in the various haemostatic and tissue remodelling processes in which platelets are involved.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.