Grant: Project Grant

Cryobiology is the study of the effects of extremely low temperatures on living systems. A major application is the low-temperature storage (cryopreservation, for example in liquid nitrogen at -196 °C) of cells and tissues to be distributed for transplantation to treat injury and disease. While many cell types have been successfully cryopreserved and used clinically for decades, some cells and the vast majority of tissues present significant hurdles for cryopreservation. For example, a widely transplanted tissue is the cornea, the clear tissue of the eye through which people see. The endothelial monolayer is the delicate layer of cells on the inner surface of the cornea that is critical to its transparency, and is the functional element that needs to be replaced in the majority of corneal transplants. Corneal endothelial monolayers cannot be adequately cryopreserved using current techniques without considerable cell loss. For this reason, currently corneal endothelial monolayer transplants (85% of all cornea transplants) must use fresh tissue, leading to tissue wastage and inequities in distribution. In addition, lab-grown corneal endothelial monolayers are poised to meet transplant needs despite donor shortage, but will require cryopreservation for widespread distribution. We are developing procedures to cryopreserve both lab-grown and natural corneal endothelial monolayers. As cellular therapies and transplant of both natural and engineered tissue are increasingly used in modern medicine, there is an urgent need for effective cryopreservation strategies. The objective of the proposed research is to combine advanced engineering modeling, cryobiological expertise, and biological experimentation to develop key understanding of identified issues in cell and tissue cryopreservation with immediate application to corneal endothelial monolayers. Proposed experiments will use cultured cells, discarded pig eyeballs, and non-transplantable donated human corneas.