Method to Predict How Tissue Size Will Change During Cryopreservation Developed

A team of scientists from Oregon State University has developed a new computer model that predicts how tissue size will change during cryopreservation. Their findings were published in Biophysical Journal.

A barrier to other uses for cryopreservation has been damage from ice crystallization and the harmful nature of the compounds added to prevent ice formation. “The problem is that these chemicals can cause osmotic damage due to water crossing cell membranes and causing the cells to burst,” lead researcher Adam Higgins said. “They can also kill cells due to toxicity. So, in designing the best vitrification method, the trick is choosing the best path between normal physiological conditions and a final vitrified state—i.e., high CPA concentration and liquid nitrogen temperature.”

The researchers found that if cells were initially exposed to a low CPA concentration and given time to swell, the sample could be vitrified after rapidly adding a high concentration. The upshot was much less overall toxicity, Higgins said. Healthy cell survival following vitrification rose from about 10% with a conventional approach to greater than 80%.

“The conventional mass transfer modeling approach is known as Fick’s law and that assumes tissue size remains constant,” Higgins said. “Our new model, which we used for two very different types of tissues, articular cartilage, and pancreatic islets, opens the door to extending our previous mathematical optimization approach to the design of better methods for the cryopreservation of various tissue types.”