How to freeze a human
Matthew Gibson, Assistant Professor, Chemistry
Published May 2015
What does your work in “freezing” at Warwick entail?
The aim of the Gibson Group’s research is to understand how we can mimic the function of antifreeze proteins; specialised proteins which enable fish to survive in arctic waters. We aim to use large synthetic molecules – polymers (plastics), which are cheaper to make, and also highly tunable. We have shown that several synthetic polymers can stop ice crystals from growing (in the same way as antifreeze proteins) and that by adding these to blood, we can improve its cryopreservation. This concept of cryopreservation is crucial in modern medicine – for example, donor blood can only be stored for around 35 days before it expires, and similar problems exist with other donor cells and tissues. We hope that by improving this process, we can increase the availability of these cells for medical procedures, and support the advances being made in regenerative medicine.
How has the science of “freezing” developed over the years?
Well, the actual understanding of what happens to water when it freezes is still under question – for example, ultra-pure water does not actually freeze until about -30 C. So, there is a lot still to be understood about how water freezes, and how to modify both its nucleation (ice formation) and growth (ice crystals getting bigger). The field was created in 1950s by Lovelock and Polge who managed to freeze sperm by adding organic solvents, which prevent ice crystals from forming. Today cryopreservation is widely used, but there is still a real need to improve it, to enable all cells to be frozen, and 100% of them recovered and ready to use.
How important is it to invest in this research?
All fundamental biology relies on using stored cells at some point to enable biological function to be probed. There’s also a huge need to improve the logistics and availability of donor cells and tissue in regenerative medicine. By continuing to invest in this research, we will be able to improve the availability and volume of cells and tissue for transplantation, and provide new tools to improve fundamental bioscience. It will also support the understanding of using synthetic molecules to mimic biological function; for example, we could rationally design a material to mimic a protein that not only helps our understanding of that protein, but also lets us apply it to real-world problems.
What does freezing do for us?
Freezing is used every day around the world - from making frozen desserts, to enabling us to store food which has been harvested, to be used in other months (or other parts of the world) when there is less available. Bone marrow transplants for leukaemia patients are often frozen to store them before usage – this alone saves hundreds of lives in the UK every year. On a global scale, freezing in the atmosphere is often the first step of rain cloud formation – without which our rivers would run dry.
What’s the future of freezing?
The goal of my lab is to have a viable product, which enables us to remove (or at least significantly reduce) the amount of organic solvent required for traditional freezing, by adding our custom-made polymers. In addition to cryopreservation, there is huge need to control ice formation on aircraft, wind turbines and even road surfaces. The world needs more ‘cool’ science!