Thromb Haemost 1994; 72(03): 408-414
DOI: 10.1055/s-0038-1648880
Original Article
Schattauer GmbH Stuttgart

Isolation and Characterization of Single-Chain Protein S

Fenny Meijer-Huizinga
The Department of Blood Coagulation, Central Laboratory of The Netherlands Red Cross Blood Transfusion Service, Amsterdam, The Netherlands
,
Koen Mertens
The Department of Blood Coagulation, Central Laboratory of The Netherlands Red Cross Blood Transfusion Service, Amsterdam, The Netherlands
,
Jan A van Mourik
The Department of Blood Coagulation, Central Laboratory of The Netherlands Red Cross Blood Transfusion Service, Amsterdam, The Netherlands
› Institutsangaben
Weitere Informationen

Publikationsverlauf

Received 18. November 1993

Accepted after resubmission 19. Mai 1994

Publikationsdatum:
25. Juli 2018 (online)

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Summary

Protein S is a vitamin K-dependent cofactor of activated protein C in the proteolytic cleavage and concomitant inactivation of the coagulation factors Va and Villa. Protein S is sensitive to proteolysis by thrombin which reduces its functional activity. Uncontrolled proteolytic breakdown, leading to the generation of a two-chain molecule, is commonly encountered during the purification of both human and bovine protein S. In this study we demonstrate that human, single-chain, intact protein S can be isolated from plasma in a single step by affinity chromatography using a monoclonal antibody, CLB PS 52, directed to an epitope located within the thrombin-sensitive region of protein S. The product of purification was readily cleaved by thrombin after Arg49, resulting in a two-chain molecule which demonstrated a lower reactivity towards CLB-PS 52 than the parent single-chain protein. This study for the first time shows that intact protein S can be isolated directly from plasma using a monoclonal antibody selected for its ability to recognize uncleaved protein S.