Fibrinogen αC-subregions critically contribute blood clot fibre growth, mechanical stability and resistance to fibrinolysis
- University of Leeds, United Kingdom
- Wake Forest University, United States
- Harvard Medical School, United States
- Universidade de Lisboa, Portugal
- University of Sheffield, United Kingdom
- University of Leeds, United States
Abstract
Fibrinogen is essential for blood coagulation. The C-terminus of the fibrinogen α-chain (αC-region) is composed of an αC-domain and αC-connector. Two recombinant fibrinogen variants (α390 and α220) were produced to investigate the role of subregions in modulating clot stability and resistance to lysis. The α390 variant, truncated before the αC-domain, produced clots with a denser structure and thinner fibres. In contrast, the α220 variant, truncated at the start of the αC-connector, produced clots that were porous with short, stunted fibres and visible fibre ends. These clots were mechanically weak and susceptible to lysis. Our data demonstrate differential effects for the αC-subregions in fibrin polymerisation, clot mechanical strength, and fibrinolytic susceptibility. Furthermore, we demonstrate that the αC-subregions are key for promoting longitudinal fibre growth. Together, these findings highlight critical functions of the αC-subregions in relation to clot structure and stability, with future implications for development of novel therapeutics for thrombosis.
Data availability
The source data for Figures 1 B-F, figure 2 B and D, figure 3 B, figure 4, figure 5 B, C and D and figure 6 A-C and D-F and supplementary Figures 1 supplement 1, figures 4 supplement 1 and figures 5 supplement 1 and 2 and figures 6 supplement 1 are made available as separate source data files.
Article and author information
Author details
Funding
British Heart Foundation (RG/13/3/30104)
- Helen McPherson
- Cedric Duval
- Stephen R Baker
- Marco M Domingues
- Victoria C Ridger
- Simon DA Connell
- Helen Philippou
- Ramzi A Ajjan
- Robert Ariens
British Heart Foundation (RG/18/11/34036)
- Helen McPherson
- Cedric Duval
- Stephen R Baker
- Victoria C Ridger
- Simon DA Connell
- Helen Philippou
- Ramzi A Ajjan
- Robert Ariens
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: Procedures were performed according to accepted standards of humane animal care, approved by the ethical review committee at the University of Leeds, and conducted under license (P144DD0D6) from the United Kingdom Home Office.
Copyright
© 2021, McPherson et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Fibrinogen αC-subregions critically contribute blood clot fibre growth, mechanical stability and resistance to fibrinolysis
eLife 10:e68761.
https://doi.org/10.7554/eLife.68761
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