This NSF CAREER award by the Biotechnology, Biochemical and Biomass Engineering program supports the development of technology for cryopreservation of cell-based therapeutics. Cell-based therapies have the potential to treat a wide variety of medical conditions, ranging from neurodegenerative diseases to cancer, and cryopreservation enables long-term storage of living cells, which would greatly facilitate supply chain management for cell therapy products. This proposal addresses two major deficiencies in current cryopreservation technology. The first is the inconvenience of removing cryoprotectant additives (CPAs) after thawing. As an example, the current procedure for removal of CPAs from red blood cells takes over an hour, making it impractical to use cryopreserved blood in emergency situations. The second deficiency relates to toxicity during vitrification, a cryopreservation strategy based on the use of high CPA concentrations to suppress ice formation. Vitrification is particularly promising for cell types that respond poorly to conventional freezing procedures, such as granulocytes. However, for vitrification to reach its full potential, new strategies are needed to minimize toxicity, particularly during CPA addition and removal. Thus, both of these deficiencies are primarily caused by inadequacies in current CPA addition and removal procedures.
The proposed research uses a novel mathematical optimization strategy to predict CPA addition and removal procedures that minimize toxicity and protocol duration, while simultaneously avoiding osmotic damage. The resulting procedures involve continuous changes in the extracellular solution composition that are not possible to implement with the centrifugation-based operations that are currently in use. This project proposes the use of microfluidic processes to impose precise control over the time-varying extracellular solution composition, enabling implementation of the mathematically optimized CPA addition and removal procedures. This work is expected to dramatically decrease the time required for CPA removal, which will greatly facilitate the use of cryopreserved cells for cell-based therapies, and it will reduce toxicity during CPA addition and removal, which will open new possibilities for vitrification of valuable cell types such as granulocytes.
The overall goal of the integrated education and outreach efforts is to foster the development of a diverse science and engineering workforce with a deep understanding of mass transfer. To this end, the objectives are to (1) develop new software tools for teaching mass transfer that allow students to conduct "virtual experiments" involving cell membrane mass transfer and microfluidic separation processes, and (2) recruit and retain Latinos in science and engineering careers by engaging Latino undergraduate and high school students in summer research projects and through participation in OSU's Latino summer camp, which serves students from grades 3 to 12.
