1
|
Chen PC, Kutzki F, Mojzisch A, Simon B, Xu ER, Aponte-Santamaría C, Horny K, Jeffries C, Schneppenheim R, Wilmanns M, Brehm MA, Gräter F, Hennig J. Structure and dynamics of the von Willebrand Factor C6 domain. J Struct Biol 2022; 214:107923. [PMID: 36410652 DOI: 10.1016/j.jsb.2022.107923] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 11/08/2022] [Accepted: 11/12/2022] [Indexed: 11/19/2022]
Abstract
Von Willebrand disease (VWD) is a bleeding disorder with different levels of severity. VWD-associated mutations are located in the von Willebrand factor (VWF) gene, coding for the large multidomain plasma protein VWF with essential roles in hemostasis and thrombosis. On the one hand, a variety of mutations in the C-domains of VWF are associated with increased bleeding upon vascular injury. On the other hand, VWF gain-of-function (GOF) mutations in the C4 domain have recently been identified, which induce an increased risk of myocardial infarction. Mechanistic insights into how these mutations affect the molecular behavior of VWF are scarce and holistic approaches are challenging due to the multidomain and multimeric character of this large protein. Here, we determine the structure and dynamics of the C6 domain and the single nucleotide polymorphism (SNP) variant G2705R in C6 by combining nuclear magnetic resonance spectroscopy, molecular dynamics simulations and aggregometry. Our findings indicate that this mutation mostly destabilizes VWF by leading to a more pronounced hinging between both subdomains of C6. Hemostatic parameters of variant G2705R are close to normal under static conditions, but the missense mutation results in a gain-of-function under flow conditions, due to decreased VWF stem stability. Together with the fact that two C4 variants also exhibit GOF characteristics, our data underline the importance of the VWF stem region in VWF's hemostatic activity and the risk of mutation-associated prothrombotic properties in VWF C-domain variants due to altered stem dynamics.
Collapse
Affiliation(s)
- Po-Chia Chen
- Structural and Computational Biology Unit, EMBL Heidelberg, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Fabian Kutzki
- Heidelberg Institute for Theoretical Studies, Schloss-Wolfsbrunnenweg 35, 69118 Heidelberg, Germany
| | - Angelika Mojzisch
- Dermatology and Venereology, University Medical Centre Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
| | - Bernd Simon
- Structural and Computational Biology Unit, EMBL Heidelberg, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Emma-Ruoqi Xu
- European Molecular Biology Laboratory, Hamburg Unit, Notkestraße 85, 22607 Hamburg, Germany
| | - Camilo Aponte-Santamaría
- Heidelberg Institute for Theoretical Studies, Schloss-Wolfsbrunnenweg 35, 69118 Heidelberg, Germany
| | - Kai Horny
- Structural and Computational Biology Unit, EMBL Heidelberg, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Cy Jeffries
- European Molecular Biology Laboratory, Hamburg Unit, Notkestraße 85, 22607 Hamburg, Germany
| | - Reinhard Schneppenheim
- Pediatric Hematology and Oncology, University Medical Centre Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
| | - Matthias Wilmanns
- European Molecular Biology Laboratory, Hamburg Unit, Notkestraße 85, 22607 Hamburg, Germany; University Medical Centre Hamburg-Eppendorf, Martinistraße 52, 20246 Hamburg, Germany
| | - Maria A Brehm
- Department of Digital Health Sciences and Biomedicine, School of Life Sciences, University of Siegen, Am Eichenhang 50, 57076 Siegen, Germany
| | - Frauke Gräter
- Heidelberg Institute for Theoretical Studies, Schloss-Wolfsbrunnenweg 35, 69118 Heidelberg, Germany; Interdisciplinary Center for Scientific Computing, Heidelberg University, INF 305, 69120 Heidelberg, Germany.
| | - Janosch Hennig
- Structural and Computational Biology Unit, EMBL Heidelberg, Meyerhofstrasse 1, 69117 Heidelberg, Germany; Chair of Biochemistry IV, Biophysical Chemistry, University of Bayreuth, 95447 Bayreuth, Germany.
| |
Collapse
|
2
|
Karsenty CL, Kirk SE, Helber HL, Esquilin JM, Despotovic JM, Grimes AB. Molecular Diagnosis Is Vital to the Accurate Classification and Management of Thrombotic Thrombocytopenic Purpura in Children. Front Immunol 2022; 13:836960. [PMID: 35479064 PMCID: PMC9038040 DOI: 10.3389/fimmu.2022.836960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 03/10/2022] [Indexed: 11/13/2022] Open
Abstract
Thrombotic thrombocytopenic purpura (TTP) is a rare but potentially life-threatening hematologic disease, presenting a myriad of diagnostic and management challenges in children. Here, we provide a review of this disorder and discuss 2 exemplary cases of TTP occurring in adolescents, emphasizing the need for consideration of late-onset congenital TTP (cTTP). We demonstrate the importance of early confirmation of ADAMTS13 enzyme deficiency and the presence or absence of ADAMTS13 inhibitor in order to rapidly initiate the appropriate life-saving therapies. Ultimately, molecular testing is paramount to distinguishing between congenital and acquired immune-mediated TTP.
Collapse
Affiliation(s)
- Cecile L. Karsenty
- Department of Pediatrics, Section of Hematology/Oncology, Baylor College of Medicine, Houston, TX, United States
- Texas Children’s Cancer and Hematology Centers, Texas Children's Hospital, Houston, TX, United States
- *Correspondence: Cecile L. Karsenty,
| | - Susan E. Kirk
- Department of Pediatrics, Section of Hematology/Oncology, Baylor College of Medicine, Houston, TX, United States
- Texas Children’s Cancer and Hematology Centers, Texas Children's Hospital, Houston, TX, United States
| | - Hannah L. Helber
- Department of Pediatrics, Section of Hematology/Oncology, Baylor College of Medicine, Houston, TX, United States
- Texas Children’s Cancer and Hematology Centers, Texas Children's Hospital, Houston, TX, United States
| | - Jose M. Esquilin
- Methodist Children’s Hospital, San Antonio, TX, United States
- Methodist Physicians Pediatric Specialists of Texas, San Antonio, TX, United States
| | - Jenny M. Despotovic
- Department of Pediatrics, Section of Hematology/Oncology, Baylor College of Medicine, Houston, TX, United States
- Texas Children’s Cancer and Hematology Centers, Texas Children's Hospital, Houston, TX, United States
| | - Amanda B. Grimes
- Department of Pediatrics, Section of Hematology/Oncology, Baylor College of Medicine, Houston, TX, United States
- Texas Children’s Cancer and Hematology Centers, Texas Children's Hospital, Houston, TX, United States
| |
Collapse
|
3
|
Alwan F, Vendramin C, Budde U, Liesner R, Taylor A, Thomas M, Lämmle B, Scully M. Assessing thrombogenesis and treatment response in congenital thrombotic thrombocytopenic purpura. EJHAEM 2021; 2:188-195. [PMID: 35845267 PMCID: PMC9175835 DOI: 10.1002/jha2.178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Revised: 02/16/2021] [Accepted: 02/17/2021] [Indexed: 11/29/2022]
Abstract
Despite clinical remission and normal platelet counts, congenital TTP (cTTP) is associated with non‐overt symptoms. Prophylactic ADAMTS13 replacement therapy such as plasma infusion (PI) prevents acute episodes and improves symptomatology. There is no current method to investigate disease severity or monitor the impact of treatment. We utilize a dynamic high shear flow assay to further understand disease pathophysiology and determine the impact of cTTP on symptomatology and therapy, despite normal platelet counts. Whole blood, under high shear, was run over collagen‐coated channels, causing platelet adhesion to von Willebrand factor (VWF) multimers. The resulting surface coverage by platelet‐VWF thrombus was assessed. The normal range was 6–39% in 50 controls. Twenty‐two cTTP patients with normal platelet counts were evaluated. Median pre‐treatment surface coverage was 89%, and PI reduced coverage to a median of 44% (p = 0.0005). Patients taking antiplatelets had further reduced coverage when combined with PI and improved non‐overt symptoms such as headache, lethargy, and abdominal pain in 100% of patients compared to 74% with PI alone (p = 0.046). We use a dynamic assay to report increased in vitro platelet adhesion and aggregation and additionally demonstrate significantly decreased thrombi following PI, with levels in the normal range levels achieved in patients taking additional antiplatelet therapy.
Collapse
Affiliation(s)
- Ferras Alwan
- Department of Haematology University College London Hospital London UK
- Haemostasis Research Unit University College London London UK
| | - Chiara Vendramin
- Department of Haematology University College London Hospital London UK
- Haemostasis Research Unit University College London London UK
| | - Ulrich Budde
- Medilys Laboratory Coagulation Asklepios Hospital Altona Hamburg Germany
| | - Ri Liesner
- Haemophilia Comprehensive Care Centre Great Ormond Street Hospital for Children NHS Trust London UK
- NIHR Great Ormond Street Hospital Biomedical Research Centre London UK
| | - Alice Taylor
- Haemophilia Comprehensive Care Centre Great Ormond Street Hospital for Children NHS Trust London UK
| | - Mari Thomas
- Department of Haematology University College London Hospital London UK
- Department of Haematology University College London Hospital Cardiometabolic Programme‐NIHR UCLH/UCL BRC London UK
| | - Bernhard Lämmle
- Department of Hematology and Central Hematology Laboratory Inselspital Bern University Hospital University of Bern Bern Switzerland
- Center for Thrombosis and Hemostasis University Medical Center Mainz Mainz Germany
| | - Marie Scully
- Department of Haematology University College London Hospital London UK
- Department of Haematology University College London Hospital Cardiometabolic Programme‐NIHR UCLH/UCL BRC London UK
| |
Collapse
|