Abstract Number: OC 13.4
Meeting: ISTH 2021 Congress
Theme: Platelet Disorders, von Willebrand Disease and Thrombotic Microangiopathies » VWF and von Willebrand Factor Disorders - Clinical Conditions
Background: Type 1 von Willebrand disease (VWD) is a heterogenous bleeding disorder caused by a quantitative defect of von Willebrand factor (VWF). Diagnosis is complicated by a lack of correlation between baseline VWF levels and bleeding severity. The response of VWF or other regulators of hemostasis to stimulation has never been evaluated as a disease modifier in type 1 VWD.
Aims: This study evaluates differential responses to stimulation between endothelial colony forming cells (ECFCs) derived from type 1 VWD patients and healthy controls.
Methods: ECFCs were isolated from 8 type 1 VWD patients and 4 healthy controls. Cells were plated to 24-well plates and stimulated with either phorbol 12-myristate 13-acetate (PMA) or a DMSO control for 1hr. Media and lysate samples were collected to measure %VWF:Ag secretion. ECFCs fixated to coverslips were stained for VWF, VE-cadherin, and DAPI for confocal microscopy. RNA was isolated for mRNA and miRNA sequencing.
Results: There was no significant difference in %VWF:Ag secretion between unstimulated and stimulated type 1 VWD ECFCs (Figure 1A). Confocal microscopy shows retention of VWF in stimulated ECFCs derived from type 1 VWD patients but not from controls (Figure 1B). Comparing control to type 1 VWD-derived ECFC mRNA profiles, no biological processes were differentially regulated in the unstimulated state, but 12 biological processes were differentially regulated in the stimulated state (Figure 2A). Differential regulation of coagulation and hemostasis in the stimulated state (adjusted p-value=0.0056) was further investigated using miRNA profiling and identified miR-23b and miR-26b as potential modulators of genes specifically related to fibrinolysis (Figure 2B).
Quantitative and Qualitative evaluation of VWF secretion in response to PMA stimulation.
mRNA and miRNA profiling of PMA stimulated control and type 1 VWD ECFCs.
Conclusions: Stimulation of control and type 1 VWD-derived ECFCs produces distinct mRNA and miRNA profiles, which may contribute to bleeding and warrants further functional investigation. Validation of these genes in an additional patient cohort is required.
To cite this abstract in AMA style:
Kloosterman R, Zago-Schmitt M, Grabell J, Thibeault L, Bowman M, Lima PDA, Tyryshkin K, Hindmarch CCT, Renwick N, James P. Transcriptional Analysis of the Response to Stimulation in ECFCs Derived from Type 1 VWD Patients [abstract]. Res Pract Thromb Haemost. 2021; 5 (Suppl 2). https://abstracts.isth.org/abstract/transcriptional-analysis-of-the-response-to-stimulation-in-ecfcs-derived-from-type-1-vwd-patients/. Accessed November 29, 2023.« Back to ISTH 2021 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/transcriptional-analysis-of-the-response-to-stimulation-in-ecfcs-derived-from-type-1-vwd-patients/