title: Pathologic mechanisms of type 1 VWD mutations R1205H and Y1584C through in vitro and in vivo mouse models.
abstract: Type 1 VWD is the mild to moderate reduction of VWF levels. This study examined the mechanisms underlying 2 common type 1 VWD mutations, the severe R1205H and more moderate Y1584C. In vitro biosynthesis was reduced for both mutations in human and mouse VWF, with the effect being more severe in R1205H. VWF knockout mice received hydrodynamic injections of mouse Vwf cDNA. Lower VWF antigen levels were demonstrated in both homozygous and heterozygous forms for both type 1 mutations from days 14-42. Recombinant protein infusions and hydrodynamic-expressed VWF propeptide to antigen ratios demonstrate that R1205H mouse VWF has an increased clearance rate, while Y1584C is normal. Recombinant ADAMTS13 digestions of Y1584C demonstrated enhanced cleavage of both human and mouse VWF115 substrates. Hydrodynamic-expressed VWF shows a loss of high molecular weight multimers for Y1584C compared with wild-type and R1205H. At normal physiologic levels of VWF, Y1584C showed reduced thrombus formation in a ferric chloride injury model while R1205H demonstrated similar thrombogenic activity to wild-type VWF. This study has elucidated several novel mechanisms for these mutations and highlights that the type 1 VWD phenotype can be recapitulated in the VWF knockout hydrodynamic injection model.
authors.affiliation: Department of Pathology and Molecular Medicine, Queen's University, Kingston, ON, Canada.
authors.forename: Cynthia M
authors.initials: CM
authors.lastname: Pruss
authors.forename: Mia
authors.initials: M
authors.lastname: Golder
authors.forename: Andrea
authors.initials: A
authors.lastname: Bryant
authors.forename: Carol A
authors.initials: CA
authors.lastname: Hegadorn
authors.forename: Erin
authors.initials: E
authors.lastname: Burnett
authors.forename: Kimberly
authors.initials: K
authors.lastname: Laverty
authors.forename: Kate
authors.initials: K
authors.lastname: Sponagle
authors.forename: Aly
authors.initials: A
authors.lastname: Dhala
authors.forename: Colleen
authors.initials: C
authors.lastname: Notley
authors.forename: Sandra
authors.initials: S
authors.lastname: Haberichter
authors.forename: David
authors.initials: D
authors.lastname: Lillicrap
mesh_terms: D051722:ADAM Proteins / Q000378:metabolism; D000071120:ADAMTS13 Protein; D000818:Animals; D002460:Cell Line; D004195:Disease Models, Animal; D006801:Humans; D008666:Metalloendopeptidases / Q000378:metabolism; D051379:Mice; D018345:Mice, Knockout; D009154:Mutation; D010641:Phenotype; D055503:Protein Multimerization; D011994:Recombinant Proteins / Q000008:administration & dosage / Q000235:genetics / Q000378:metabolism; D013927:Thrombosis / Q000235:genetics; D014842:von Willebrand Diseases / Q000235:genetics*; D014841:von Willebrand Factor / Q000008:administration & dosage / Q000235:genetics* / Q000378:metabolism
chemical_list: D011994:Recombinant Proteins; D014841:von Willebrand Factor; D051722:ADAM Proteins; C502939:ADAMTS13 protein, mouse; D008666:Metalloendopeptidases; D000071120:ADAMTS13 Protein; C099604:ADAMTS13 protein, human