The browser you are using is not supported by this website. All versions of Internet Explorer are no longer supported, either by us or Microsoft (read more here: https://www.microsoft.com/en-us/microsoft-365/windows/end-of-ie-support).

Please use a modern browser to fully experience our website, such as the newest versions of Edge, Chrome, Firefox or Safari etc.

Anti-factor V auto-antibody in the plasma and platelets of a patient with repeated gastrointestinal bleeding

På svenska

Author

  • E Ajzner
  • I Balogh
  • G Haramura
  • Z Boda
  • K Kalmar
  • G Pfliegler
  • Björn Dahlbäck
  • L Muszbek

Summary, in English

Development of autoantibody against coagulation factor V (FV) is a rare clinical condition with hemorrhagic complications of varying severity. The aim of this study was to establish the pathomechanism of an acquired FV deficiency and characterize the FV inhibitor responsible for the clinical symptoms. A 78-year-old female was admitted to hospital with severe gastrointestinal bleeding. General clotting tests and determination of clotting factors were performed by standard methods. FV antigen and FV containing immune complexes were measured by ELISA. The FV molecule was investigated by Western blotting and by sequencing the f5 gene. The binding of patient's IgG to FV and activated FV (FVa) was demonstrated in an ELISA system and its effect on the procoagulant activity of FVa was tested in clotting tests and in a chromogenic prothrombinase assay. Localization of the epitope for the antibody was performed by blocking ELISA. FV activity was severely suppressed both in plasma and platelets. FV antigen levels were normal by ELISA using polyclonal anti-FV antibody or monoclonal antibody against the connecting region of FV, but depressed when HV1 monoclonal antibody against the C2 domain in the FV light-chain was used as capture antibody. The FV molecule was found intact. An IgG reacting with both FV and FVa was present in the patient's plasma and its binding to FV was inhibited by HV1 antibody. FV-containing immune complexes were detected in the patient's plasma and platelet lysate. The patient's IgG inhibited the procoagulant function of FVa. An anti-FV IgG was present in the patient's plasma and platelets. The autoantibody reacted with an epitope in the C2 domain of FV light chain and neutralized the procoagulant function of FVa.

Publishing year

2003

Language

English

Pages

943-949

Publication/Series

Journal of Thrombosis and Haemostasis

Volume

1

Issue

5

Document type

Journal article

Publisher

Wiley-Blackwell

Topic

  • Cardiac and Cardiovascular Systems

Keywords

  • hemorrhagic diathesis
  • factor V
  • factor V inhibitor
  • platelets

Status

Published

Research group

  • Clinical Chemistry, Malmö

ISBN/ISSN/Other

  • ISSN: 1538-7933