Impact of Different Cooling Methods on the Stability of Peripheral Blood Mononuclear Cells (PBMCs)

During cryopreservation of peripheral blood mononuclear cells (PBMCs), there are several recognized cooling methods, which include different cooling rates that might influence the stability of the PBMCs. This chapter will focus on three cooling methods trialled and will describe the different principles they are based on and the outcomes. One cooling method is based on repeatable −1°C/min cooling rate that requires only isopropyl alcohol (method A). The second cooling method is based on the cooling rate of −1° C/min solely (method B). The third cooling method is based on a user-predefined programmable controlled rate of freezing (method C). The first method was discontinued for safety reasons. A small comparative study was performed using 12 cell preparation tubes (CPT) using methods B and C. Cell Viability was measured based on the difference between pre-thaw and post-thaw viability percentages that were obtained from the flow cytometry. From our data, we conclude that although there were no significant differences in the outcomes of the comparative study of cooling methods, the use of either method B or C are the most suitable for long-term storage that will preserve the quality of the sample suitable for future research and clinical applications