Freezing under pressure: a new method for cryopreservation

Area of Science:

• Biomedical Engineering
• Cell Biology
• Cryobiology

Background:

• Cryopreservation is vital for medicine and research.
• Current cryoprotective agents (CPAs) are toxic at high concentrations.
• Cellular damage during freezing and thawing remains a challenge.

Purpose of the Study:

• To investigate the effect of pressure on red blood cell (RBC) hemolysis during cryopreservation.
• To evaluate the efficacy of low CPA concentrations combined with pressure.
• To mitigate the toxicity associated with conventional cryopreservation methods.

Main Methods:

• Human red blood cells were subjected to freezing and thawing under varying pressures.
• Low concentrations of dimethyl sulfoxide (Me2SO) or glycerol were used as CPAs.
• Hemolysis was measured to assess cell membrane integrity.

Main Results:

• A minimum in hemolysis was observed at approximately 120 MPa.
• Using 120 MPa with 5% Me2SO or 8% glycerol resulted in ≤8% hemolysis.
• Effective cryopreservation was achieved at cooling rates of 35 °C/min or 160 °C/min.

Conclusions:

• Applying pressure during cryopreservation significantly reduces RBC damage.
• Low CPA concentrations combined with pressure offer a less toxic alternative.
• This method shows potential for improving cell, tissue, and organ preservation.