Haemostasis pp 365-372 | Cite as

Protein C

  • Mirta Hepner
  • Vasiliki Karlaftis
Part of the Methods in Molecular Biology book series (MIMB, volume 992)


Protein C (PC) is a 62-kDa vitamin K-dependent plasma zymogen which, after activation to serine protease, plays an important role in the physiologic regulation of blood coagulation.

Given that PC is one of the major naturally occurring inhibitors of coagulation, acquired or hereditary deficiencies of this protein result in excessive thrombin generation. As a vast array of mutations are responsible for hereditary PC deficiencies, screening for their presence by DNA testing would require sequencing each entire gene involving numerous exons. Moreover, the knowledge of the gene mutation does not offer any benefit in the treatment of thrombophilic families, so the routine molecular characterization is not indicative. These defects are detected by functional or immunological assays. Measurement of PC activity is essential to identify subjects with both type I and type II PC defects. There is no need to routinely perform PC immunological assays. However, they are useful in order to distinguish type I from type II PC hereditary deficiency.

Key words

Protein C Thrombophilia Functional assay Immunological assay Blood coagulation inhibitor Acquired deficiency Hereditary deficiency 


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Copyright information

© Humana Press 2013

Authors and Affiliations

  • Mirta Hepner
    • 1
  • Vasiliki Karlaftis
    • 2
  1. 1.Laboratorio de Hemostasia y TrombosisHospital de Pediatría “Prof. Dr. Juan P. Garrahan”Buenos AiresArgentina
  2. 2.Haematology Research LaboratoryMurdoch Children’s Research InstituteMelbourneAustralia

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