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Thromb Haemost 2000; 84(06): 942-948
DOI: 10.1055/s-0037-1614153
DOI: 10.1055/s-0037-1614153
Review Article
Issues with the Assay of Factor VIII Activity in Plasma and Factor VIII Concentrates
Roger L. Lundblad
1
From the Department of Pathology, University of North Carolina, Chapel Hill, USA
2
Baxter Healthcare – Hyland Immuno Division, Duarte, CA, USA
,
Henry S. Kingdon
3
Baxter Healthcare – Hyland Immuno Division (Lake Cook, IL), USA
,
Kenneth G. Mann
4
Department of Biochemistry, University of Vermont, Burlington, VT, USA
,
Gilbert C. White
5
Department of Medicine, Division of Hematology-Oncology, University of North Carolina at Chapel Hill, USA
› InstitutsangabenThe authors wish to thanks Drs. Gordon Bray, Edward Gomperts, Barry Woodham, Jerry Powell, Don Baker and Professor Hans Peter Schwarz for their helpful comments in the preparation of this manuscript.Weitere Informationen
Publikationsverlauf
Received
22. Juni 1999
Accepted after resubmission
03. August 2000
Publikationsdatum:
13. Dezember 2017 (online)
Summary
A review of the literature suggests that assays accurate for the determination of factor VIII in plasma samples may not necessarily retain this accuracy when used for the determination of factor VIII in high-purity factor VIII concentrates such as Hemofil ® M. Review of assay data suggests that it is imperative to obtain maximal activation of the factor VIII in the sample with thrombin when using an assay system of isolated coagulation factors such as the two-stage assay or the various chromogenic substrate assays. Based on a combination of ease and reproducibility of performance and correlation of in vivo and in vitro measurements, it is recommended that the one-stage activated partial thromboplastin time performed with plasma from an individual with severe hemophilia A be used for the measurement of factor VIII potency. Chromogenic substrate assays can be used if care is taken to assure optimal activation of factor VIII by thrombin in the assay and the presence of sufficient factor IXa, phospholipid and calcium ions to stabilize factor Villa during the assay process.
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