Abstract Number: PB1529
Meeting: ISTH 2020 Congress
Theme: Platelet Disorders and von Willebrand Disease » von Willebrand Factor Biology
Background: The multimeric composition of recombinant von Willebrand factor (rVWF) concentrate as well as platelet VWF (plateletVWF) is different compared to plasma-derived VWF (pdVWF). rVWF as well as plateletVWF retain full-spectrum multimers with a higher proportion of ultra-large multimers (ULM).
Aims: We aimed to characterize and compare structural and functional properties of plateletVWF, pdVWF, and rVWF.
Methods: pdVWF was obtained from whole blood of 10 healthy volunteers and plateletVWF was isolated after centrifugation, two washing steps and application of detergent. Two approved and commercially available plasma derived VWF concentrates and a recombinant VWF were tested. Standard assays (IL Instrumentation Laboratory, Bedford, MA, USA) for 1) VWF:Ag, 2) VWF:GP1bM, and VWF:GP1bR, 3) VWF:CBA were used. Gel electrophoresis served for multimeric analysis.
Results: For optimized comparability VWF measurements were standardized for VWF:Ag (=100%). Results for VWF:Ag and activity parameters are shown in table 1 and 2. Multimer analysis showed the previously described structural differences with both rVWF and plateletVWF containing a high portion of ultra-large multimers (plateletVWF >rVWF>pdVWF) and the absence of triplet bands compared to pdVWF or pdVWF concentrates.
| VWF:Ag | VWF:GP1bM | VWF:GP1bR | VWF:CBA | |
| pdVWF concentrate 1 | 100 | 71 | 82 | 58 |
| pdVWF concentrate 2 | 100 | 70 | 78 | 50 |
| rVWF concentrate | 100 | 120 | 105 | 110 |
[Table 1: Analysis of commercial VWF products (measured in duplicates).]
| VWF:Ag | VWF:GP1bM | VWF:GP1bR | VWF:CBA | |
| plateletVWF | 100 ± 21 | 142 ± 44* | 46 ± 8* | 72 ± 15* |
| pdVWF | 100 ± 36 | 90 ± 39 | 81 ± 34 | 99 ± 29 |
[Table 2: Analyses of pVWF and pdVWF from healthy donors (n=10; mean ± SD). * denotes statistically significant difference to pdVWF.]
Conclusions: Significant functional and structural differences between plasmatic, platelet and recombinant VWF could be demonstrated. Importantly, the rVWF preparation clinically used as an equivalent of the plasmatic VWF, shows partial structural and functional similarities to plateletVWF with comparable values of activity parameters and multimeric structure potentially implying improved hemostatic efficacy compared to pdVWF.
To cite this abstract in AMA style:
Kragh T, Spannagl M, Ott HW, Möhnle P, Pekrul I. The Super Glue of Ultra-Large Multimers – Characterisation of Recombinant and Platelet Derived von Willebrand Factor [abstract]. Res Pract Thromb Haemost. 2020; 4 (Suppl 1). https://abstracts.isth.org/abstract/the-super-glue-of-ultra-large-multimers-characterisation-of-recombinant-and-platelet-derived-von-willebrand-factor/. Accessed January 21, 2022.« Back to ISTH 2020 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/the-super-glue-of-ultra-large-multimers-characterisation-of-recombinant-and-platelet-derived-von-willebrand-factor/