Improved performance characteristics of the von Willebrand factor ristocetin cofactor activity assay using a novel automated assay protocol.
(2010) In Journal of Thrombosis and Haemostasis 8. p.2216-2223- Abstract
- Summary Background, objectives and methods: An accurate, sensitive and precise assay for reliable determination of the ristocetin cofactor activity of von Willebrand factor (VWF:RCo) in plasma and von Willebrand Factor (VWF)-containing concentrates has been evaluated. The assay is based on a commercially available automated protocol with modifications including a combination of adding additional ristocetin and the use of two calibration curves for the high and low measuring ranges. Results: Addition of extra ristocetin resulted in improved measurement of VWF recoveries from various VWF-containing concentrates that were underestimated using the standard automated protocol. The modifications resulted in improved assay performance over an... (More)
- Summary Background, objectives and methods: An accurate, sensitive and precise assay for reliable determination of the ristocetin cofactor activity of von Willebrand factor (VWF:RCo) in plasma and von Willebrand Factor (VWF)-containing concentrates has been evaluated. The assay is based on a commercially available automated protocol with modifications including a combination of adding additional ristocetin and the use of two calibration curves for the high and low measuring ranges. Results: Addition of extra ristocetin resulted in improved measurement of VWF recoveries from various VWF-containing concentrates that were underestimated using the standard automated protocol. The modifications resulted in improved assay performance over an extended measuring range (2.00 - 0.03 IU/mL). Accuracy was tested using VWF deficiency plasma spiked with 1(st) international standard for VWF concentrate. Seven dilutions, ranging between 1.80 and 0.05 IU/mL, were analyzed and resulted in measured concentrations between 80% and 100% of the assigned potency of the standard. Linearity was determined from the regression plot of the same concentrate dilutions and resulted in a correlation coefficient of 0.998. The repeatability, expressed as coefficient of variation, was 2% in the normal range (0.90 IU/mL) and 8% at the level of 0.05 IU/mL. The corresponding reproducibility results were 2% and 15% at the normal and low measuring ranges, respectively. Conclusions: Analysis of patients with von Willebrand disease indicates that the modified automated BCS((R)) protocol has a superior discrimination power compared with the standard protocol. This is especially true in samples with low VWF, as in patients with type 3 von Willebrand disease. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1665135
- author
- Hillarp, Andreas LU ; Stadler, M ; Haderer, C ; Weinberger, J ; Kessler, C M and Römisch, J
- organization
- publishing date
- 2010
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Journal of Thrombosis and Haemostasis
- volume
- 8
- pages
- 2216 - 2223
- publisher
- Wiley-Blackwell
- external identifiers
-
- wos:000282642500018
- pmid:20727070
- scopus:78649360891
- ISSN
- 1538-7933
- DOI
- 10.1111/j.1538-7836.2010.04029.x
- language
- English
- LU publication?
- yes
- id
- ffe3626b-c068-4faf-8ed4-81b3d6ef192c (old id 1665135)
- alternative location
- http://www.ncbi.nlm.nih.gov/pubmed/20727070?dopt=Abstract
- date added to LUP
- 2016-04-04 07:02:18
- date last changed
- 2022-04-23 03:52:32
@article{ffe3626b-c068-4faf-8ed4-81b3d6ef192c,
abstract = {{Summary Background, objectives and methods: An accurate, sensitive and precise assay for reliable determination of the ristocetin cofactor activity of von Willebrand factor (VWF:RCo) in plasma and von Willebrand Factor (VWF)-containing concentrates has been evaluated. The assay is based on a commercially available automated protocol with modifications including a combination of adding additional ristocetin and the use of two calibration curves for the high and low measuring ranges. Results: Addition of extra ristocetin resulted in improved measurement of VWF recoveries from various VWF-containing concentrates that were underestimated using the standard automated protocol. The modifications resulted in improved assay performance over an extended measuring range (2.00 - 0.03 IU/mL). Accuracy was tested using VWF deficiency plasma spiked with 1(st) international standard for VWF concentrate. Seven dilutions, ranging between 1.80 and 0.05 IU/mL, were analyzed and resulted in measured concentrations between 80% and 100% of the assigned potency of the standard. Linearity was determined from the regression plot of the same concentrate dilutions and resulted in a correlation coefficient of 0.998. The repeatability, expressed as coefficient of variation, was 2% in the normal range (0.90 IU/mL) and 8% at the level of 0.05 IU/mL. The corresponding reproducibility results were 2% and 15% at the normal and low measuring ranges, respectively. Conclusions: Analysis of patients with von Willebrand disease indicates that the modified automated BCS((R)) protocol has a superior discrimination power compared with the standard protocol. This is especially true in samples with low VWF, as in patients with type 3 von Willebrand disease.}},
author = {{Hillarp, Andreas and Stadler, M and Haderer, C and Weinberger, J and Kessler, C M and Römisch, J}},
issn = {{1538-7933}},
language = {{eng}},
pages = {{2216--2223}},
publisher = {{Wiley-Blackwell}},
series = {{Journal of Thrombosis and Haemostasis}},
title = {{Improved performance characteristics of the von Willebrand factor ristocetin cofactor activity assay using a novel automated assay protocol.}},
url = {{http://dx.doi.org/10.1111/j.1538-7836.2010.04029.x}},
doi = {{10.1111/j.1538-7836.2010.04029.x}},
volume = {{8}},
year = {{2010}},
}