Modeling approaches towards improved cryopreservation
Description: Cryopreservation touches all aspects of modern biology. It enables species conservation, modern animal agriculture, cell, tissue and organ transplantation and transfusion, and reproductive technologies that bene-fit all aspects of Canadian life and economy. The study of life at low temperatures, cryobiology addresses the deep interactions of physical and organic chemistry, heat and mass transfer, cell and tissue biology, physiology and mechanobiology, among many others. The central hypothesis of my research is that understanding these deep interactions during cryopreservation is facilitated by mathematical and computational models. My long-term goal is to build models that reflect the physics of freezing cells and tissues and the biological mechanisms of associated damage. My program of research has created preliminary modeling and computational frameworks that I will use here to facilitate questions on three major fronts: cryoprotectant equilibration, ice propagation, and damage modelling. First, we aim to build and validate models of cryoprotectant transport in tissues. Cryoprotectant (CPA) equilibration is a limiting step in the cryopreservation process and is associated with mechanical stress due to osmotic forces and chemical stresses [40]. My group recently created continuum and agent-based models of this process [7,37], as well as novel cell and tissue-level CPA toxicity models [4,15], and has been the first to establish an experimentally informed agent-based model of mechanical damage to tissues [7]. To expand to larger tissues, I propose to use the novel 4D confocal microscopy techniques my group has developed to inform mechanobiological and cell and tissue level transport parameters for these models us-ing a bovine ovary model system. Second, we aim to expand our basic model of cell-to-cell ice propagation in tissues. Ice propagation and subsequent recrystallization is the other critical step to avoid in the cryopreservation process [40]. Our recent work has shown that classical models of ice propagation can be adopted to be used in our agent-based modeling scheme [8]. There is almost no experimental data available describing ice propagation kinetics. I propose to use a combination of 4D cryomicroscopy and 3D tissue culture to construct and test ice propagation among different tissue geometries and cell locations. Third, we aim to establish and expand cryoinjury models, and account for the effects of tissue geometry and heterogeneity. My group's recent efforts have expanded models of accumulated damage to include principles from mechanobiology and multisolute "cocktail" toxicity [4,28,37]. However, these models need further exploration and do not capture the effects of heterogenous cell populations and 3D configurations on the sensitivity to CPAs and mechanical stress. I propose to re-evaluate both mechanical stress and toxicity models in the context of heterogenous systems in 3D culture systems and in tissue pieces.
Amount: CA$45,000
Funding type: research
Funder scheme: Discovery Grants Program - Individual
Start date: 2023-04-01
End date: 2024-03-31
Investigator: James Benson
Institution: University of Saskatchewan
Funded outputs count: 7
Funder award ID: rgpin-2023-04007
OpenAlex ID: G7908997493