Storage of factor VIII variants with impaired von Willebrand factor binding in Weibel-Palade bodies in endothelial cells.
BACKGROUND: Point mutations resulting in reduced factor VIII (FVIII) binding to von Willebrand factor (VWF) are an important cause of mild/moderate hemophilia A. Treatment includes desmopressin infusion, which concomitantly increases VWF and FVIII plasma levels, apparently from storage pools contain...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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Public Library of Science (PLoS)
2011-01-01
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| Series: | PLoS ONE |
| Online Access: | http://europepmc.org/articles/PMC3166073?pdf=render |
| _version_ | 1818031041512734720 |
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| author | Maartje van den Biggelaar Eveline A M Bouwens Jan Voorberg Koen Mertens |
| author_facet | Maartje van den Biggelaar Eveline A M Bouwens Jan Voorberg Koen Mertens |
| author_sort | Maartje van den Biggelaar |
| collection | DOAJ |
| description | BACKGROUND: Point mutations resulting in reduced factor VIII (FVIII) binding to von Willebrand factor (VWF) are an important cause of mild/moderate hemophilia A. Treatment includes desmopressin infusion, which concomitantly increases VWF and FVIII plasma levels, apparently from storage pools containing both proteins. The source of these VWF/FVIII co-storage pools and the mechanism of granule biogenesis are not fully understood. METHODOLOGY/PRINCIPAL FINDINGS: We studied intracellular trafficking of FVIII variants implicated in mild/moderate hemophilia A together with VWF in HEK293 cells and primary endothelial cells. The role of VWF binding was addressed using FVIII variants displaying reduced VWF interaction. Binding studies using purified FVIII proteins revealed moderate (Arg2150His, Del2201, Pro2300Ser) to severe (Tyr1680Phe, Ser2119Tyr) VWF binding defects. Expression studies in HEK293 cells and primary endothelial cells revealed that all FVIII variants were present within VWF-containing organelles. Quantitative studies showed that the relative amount of FVIII storage was independent of various mutations. Substantial amounts of FVIII variants are co-stored in VWF-containing storage organelles, presumably by virtue of their ability to interact with VWF at low pH. CONCLUSIONS: Our data suggest that the potential of FVIII co-storage with VWF is not affected in mild/moderate hemophilia A caused by reduced FVIII/VWF interaction in the circulation. These data support the hypothesis that Weibel-Palade bodies comprise the desmopressin-releasable FVIII storage pool in vivo. |
| first_indexed | 2024-12-10T05:45:10Z |
| format | Article |
| id | doaj.art-2cbc4f2272d14a2992a6410e79ceeea1 |
| institution | Directory Open Access Journal |
| issn | 1932-6203 |
| language | English |
| last_indexed | 2024-12-10T05:45:10Z |
| publishDate | 2011-01-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS ONE |
| spelling | doaj.art-2cbc4f2272d14a2992a6410e79ceeea12022-12-22T02:00:10ZengPublic Library of Science (PLoS)PLoS ONE1932-62032011-01-0168e2416310.1371/journal.pone.0024163Storage of factor VIII variants with impaired von Willebrand factor binding in Weibel-Palade bodies in endothelial cells.Maartje van den BiggelaarEveline A M BouwensJan VoorbergKoen MertensBACKGROUND: Point mutations resulting in reduced factor VIII (FVIII) binding to von Willebrand factor (VWF) are an important cause of mild/moderate hemophilia A. Treatment includes desmopressin infusion, which concomitantly increases VWF and FVIII plasma levels, apparently from storage pools containing both proteins. The source of these VWF/FVIII co-storage pools and the mechanism of granule biogenesis are not fully understood. METHODOLOGY/PRINCIPAL FINDINGS: We studied intracellular trafficking of FVIII variants implicated in mild/moderate hemophilia A together with VWF in HEK293 cells and primary endothelial cells. The role of VWF binding was addressed using FVIII variants displaying reduced VWF interaction. Binding studies using purified FVIII proteins revealed moderate (Arg2150His, Del2201, Pro2300Ser) to severe (Tyr1680Phe, Ser2119Tyr) VWF binding defects. Expression studies in HEK293 cells and primary endothelial cells revealed that all FVIII variants were present within VWF-containing organelles. Quantitative studies showed that the relative amount of FVIII storage was independent of various mutations. Substantial amounts of FVIII variants are co-stored in VWF-containing storage organelles, presumably by virtue of their ability to interact with VWF at low pH. CONCLUSIONS: Our data suggest that the potential of FVIII co-storage with VWF is not affected in mild/moderate hemophilia A caused by reduced FVIII/VWF interaction in the circulation. These data support the hypothesis that Weibel-Palade bodies comprise the desmopressin-releasable FVIII storage pool in vivo.http://europepmc.org/articles/PMC3166073?pdf=render |
| spellingShingle | Maartje van den Biggelaar Eveline A M Bouwens Jan Voorberg Koen Mertens Storage of factor VIII variants with impaired von Willebrand factor binding in Weibel-Palade bodies in endothelial cells. PLoS ONE |
| title | Storage of factor VIII variants with impaired von Willebrand factor binding in Weibel-Palade bodies in endothelial cells. |
| title_full | Storage of factor VIII variants with impaired von Willebrand factor binding in Weibel-Palade bodies in endothelial cells. |
| title_fullStr | Storage of factor VIII variants with impaired von Willebrand factor binding in Weibel-Palade bodies in endothelial cells. |
| title_full_unstemmed | Storage of factor VIII variants with impaired von Willebrand factor binding in Weibel-Palade bodies in endothelial cells. |
| title_short | Storage of factor VIII variants with impaired von Willebrand factor binding in Weibel-Palade bodies in endothelial cells. |
| title_sort | storage of factor viii variants with impaired von willebrand factor binding in weibel palade bodies in endothelial cells |
| url | http://europepmc.org/articles/PMC3166073?pdf=render |
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