Non RVC Supervisors: Prof. Tom Carter
Department: Comparative Biomedical Sciences
Background, aims and objectives:
Equine and human endothelial cells share many conserved features and the same functional requirements (roles in blood flow, haemostasis, inflammation and angiogenesis), however there are stark differences in some specific aspects of equine endothelial biology. This project focuses on the structure, storage and function of Von Willebrand Factor (VWF) in equine endothelial cells compared to human endothelial cells. Endothelial cells line blood vessels and are responsible for regulating blood vessel tone, inflammation and coagulation. VWF is produced and stored in endothelial cells and is essential for haemostasis. It is stored in a highly organised fashion in its storage organelle, the Weibel-Palade body (WPB). In human endothelial cells the organisation of VWF within the WPB gives WPBs their classic rod-shaped morphology. This is essential for the regulated secretion of VWF and formation of long extracellular strings to capture platelets from circulating blood to initiate thrombosis. We have discovered that equine endothelial cells possess VWF storage organelles with a spherical rather than rod-shaped morphology. We hypothesise that the altered morphology indicates disordered storage of VWF and will therefore result in shorter VWF strings which are less able to capture platelets.
This studentship will elucidate the mechanisms underlying storage of VWF in equine WPB and the functional consequences for platelet capture and activation following acute secretion. Equine endothelial cells will be compared to human endothelial cells in the following studies:
- The storage of VWF in WPB will be examined using transmission electron microscopy.
- The various processing steps to achieve ordered storage of VWF will be investigated using chemical manipulation of cultured endothelial cells and the potential causes of the altered morphology identified.
- The respective roles of VWF itself or the cell machinery involved in creating the spherical morphology will be investigated by expressing the equine protein and generating WPB in non-endothelial HEK-293 cells.
- The function of equine VWF will be examined by stimulating acute secretion from cells exposed to flow conditions, to generate VWF strings.
- The length of these strings and their ability to capture platelets will be measured and the role of ADAMTS13 in regulating VWF cleavage will be investigated.
- The project may be extended to include assessment of the role of VWF in equine clinical cases at risk of systemic inflammatory response syndrome (SIRS)-associated coagulopathies.
This project suits a candidate with an interest in cardiovascular/endothelial cell biology and a background in biomedical or veterinary sciences, physiology, cell biology or a related discipline. The project will provide training in a wide range of biochemical and molecular techniques, advanced cellular imaging as well as assessment of endothelial cell and platelet function.
- Segura, D., Monreal, L., Pérez-Pujol, S., Pino, M., Ordinas, A., Brugués, R., White, J.G. and Escolar, G. Assessment of Platelet Function in Horses: Ultrastructure, Flow Cytometry, and Perfusion Techniques. Journal of Veterinary Internal Medicine 20, 581-588, 2006.
- Zupancic G, Ogden D, Magnus CJ, Wheeler-Jones C, Carter TD. Differential exocytosis from human endothelial cells evoked by high intracellular Ca2+ concentration. The Journal of Physiology 544, 741-55, 2002.
- Ferraro, F., S. Mafalda Lopes da, W. Grimes, H.K. Lee, R. Ketteler, J. Kriston-Vizi, and D.F. Cutler. Weibel-Palade body size modulates the adhesive activity of its von Willebrand Factor cargo in cultured endothelial cells. Scientific Reports 6, 32473, 2016.
- Erent, M., Meli, A., Moisoi, N., Babich, V., Hannah, M.J., Skehel, P., Knipe, L., Zupančič, G., Ogden, D. and Carter, T. Rate, extent and concentration dependence of histamine-evoked Weibel–Palade body exocytosis determined from individual fusion events in human endothelial cells. The Journal of Physiology, 583, 195-212, 2007.
- Must meet our standard PhD entry requirements
- Applicants must have a minimum of a 2:1 BSc or equivalent in a relevant subject as well as previous experience in a research laboratory
- Strong interest in cardiovascular cell biology and physiology
- Evidence of good communication skills
- Experience of in vitro investigation of endothelial cells and/or platelets (human or animal)
- Experience of working with human or animal blood or tissue samples
Whilst there will be no use of research animals in this project, the study will use blood and tissue samples from horses post-mortem and potentially from clinical cases. These samples will be collected by experienced colleagues and training will be provided if the candidate wishes to develop these skills.
This is a 3 year fully-funded studentship, covering tuition fees and stipend. This studentship is open to applicants eligible for "Home" fees. International applicants are welcome to apply but must be able to fund the difference between "Home" and "Overseas" tuition fees.
The studentship will commence October 2023.
How to Apply
For more information on the application process and English language requirements see please see How to Apply.
If you are interested in applying for this position, please follow the link below. Please use your personal statement to demonstrate any laboratory experience and research projects you have been involved with, and your interest and engagement with cardiovascular cell biology and physiology.
Interviews will be held March 2023 (specific date TBC).
We welcome informal enquiries - these should be directed to Dr Elizabeth Finding: firstname.lastname@example.org