Jason Acker,

• Blood Cell Cryopreservation and Desiccation 
• Microfluidic Devices for Blood Testing

Each year, millions of units of blood are collected from donors and transfused into recipients. Such large volumes are possible only because we can maintain the quality of donated red blood cells (RBCs) for prolonged periods of time in modern blood banks. Effective RBC preservation procedures are necessary to maintain the integrity and function of donated RBCs. Only then can blood product manufacturers perform the many steps necessary to ensure a safe and readily available blood supply.

To successfully store RBCs, the normal cell functions are suppressed by refrigeration to below body temperature. Refrigerated storage slows down the aging of the cells, but unfortunately does not prevent cell injury over time. The resulting decline in the quality of refrigerated RBCs has been strongly linked to changes that occur in the cell membrane. We have developed a method that uses liposomes to stabilize the membranes of stored RBCs. Liposomes are microscopic hollow spherical fat droplets that can be manufactured to contain drugs or other substances. When such liposomes are mixed with cells, the contents can transfer into the cells. Liposomes have also been used recently to reduce the damage to blood cells following freezing and drying.

Cryopreservation is the process whereby biological function is maintained by freezing and storage at ultra-low subzero temperatures. Unfortunately, blood cell cryopreservation remains an expensive procedure that requires highly trained technicians and specialized equipment for processing and storage making it logistically prohibitive for routine use in large-scale operations. Recent advances in cryobiology research have resulted in a new method for the cryopreservation of mammalian cells using low concentrations of intracellular sugars to protect cells. Sugars have been shown to be important stabilizers of membranes, proteins and other key cellular structures in natural systems that undergo extreme environmental stresses such as desiccation and freezing. Dr. Acker's work focuses on the development of strategies for the introduction of protective amounts of intracellular protectants into human blood cells.

Dry storage of mammalian cells promises to eliminate many of the problems associated with current clinical cryopreservation, providing a more effective method for the ambient temperature, long-term storage of blood cells. Dr. Acker's group is working to better understand the effects of desiccation and drying on blood cell structure and function.

In addition to his work in biopreservation, Dr. Acker has an active research interest in the use of microfabrication and microfluidics technology in diagnostic testing. Using tools developed for the microelectronics industry to fabricate micro-scale devices for integrated chemical and biological processing and analysis, the research group in Edmonton is developing novel, cost-effective, automated devices for blood testing.

Selected Publications:

Kanias, T. and Acker, J.P. Trehalose loading into red blood cells is accompanied with hemoglobin oxidation and membrane lipid peroxidation. Cryobiology 58 (2): 232-239 (2009).

Holovati, J.L., Gyongyossy-Issa, M.I.C., Acker, J.P. Effects of trehalose-loaded liposomes on red blood cell membrane quality following freezing and thawing. Cryobiology 58 (1): 75- 83 (2009).

Acker, J.P., Holovati, J.L., Hannon, J., Issa-Gyongyosy, M.I.C. Blood Biopreservation Workshop: New and Emerging Trends in Research and Clinical Practice. Transfusion Medicine Review 23 (1): 25-41 (2009).

Webster, J., Croteau, I.M, and Acker, J.P. Evaluation of the Canadian Blood Services red blood cell shipping container. Canadian Journal of Medical Laboratory Science 70 (5): 167-176 (2008).

Holovati, J.L., Wong, K.A., Webster, J.M. and Acker, J.P. Effect of cryopreservation on the red blood cell microvesiculation, phosphatidylserine externalization, and CD47 expression. Transfusion 48(8): 1658-1668 (2008).

Podlosky, L., Poirier, A., Nahirniak, S., Clarke, G. and Acker, J.P. Viability of AS-3 and SAG-M red cells stored in plastic syringes for pediatric transfusion. Transfusion 48(7): 1300-1307 (2008).

Acker, J.P., Fowler, A., Lauman, B., Cheley, S. and Toner, M. Survival of desiccated mammalian cells: Beneficial effects of isotonic Media Room. Cell Preservation Technology 1 (2): 129-140 (2002).

Acker, J.P. and McGann, L.E. Innocuous intracellular ice improves the survival of frozen cells. Cell Transplantation 11 (6): 563-571 (2002).

Chen, T., Acker, J.P., Eroglu, A., Cheley, S., Bayley, H., Fowler, A. and Toner, M. Beneficial effect of intracellular trehalose on the membrane integrity of dried mammalian cells. Cryobiology 43 (2): 168-181 (2001).

Yang, H., Acker, J.P., Hannon, J., Miszta-Lane, H., Akabutu, J. and McGann, L.E. Damage and protection of umbilical cord blood cells during cryopreservation. Cytotherapy 3 (5): 377-386 (2001).

Acker, J.P., Elliott, J.A.W. and McGann, L.E. Intercellular ice propagation: Experimental evidence for ice growth through membrane pores. Biophysical Journal 81 (3): 1389-1397 (2001).