Sound waves for solving the problem of recrystallization in cryopreservation

Area of Science:

• Biomedical Engineering
• Cryobiology
• Regenerative Medicine

Background:

• Cryopreservation of biological samples, including organs, faces challenges in rapid and uniform rewarming.
• Recrystallization during rewarming is a major obstacle, causing cellular damage.
• Current cryopreservation methods require advancements in rewarming techniques to preserve larger biological systems.

Purpose of the Study:

• To present a proof-of-principle for High Intensity Focused Ultrasound (HIFU) as a rewarming technology for cryopreserved samples.
• To demonstrate the efficacy of HIFU in preventing recrystallization and achieving uniform heating.
• To explore the potential of HIFU for cryopreservation of millimeter-scale biological systems.

Main Methods:

• Utilized the nematode Caenorhabditis elegans as a model system for cryopreservation studies.
• Applied High Intensity Focused Ultrasound (HIFU) waves for rapid rewarming of cryopreserved C. elegans.
• Monitored rewarming in real-time using MRI thermography and controlled heating with acoustic interferometry.

Main Results:

• Successfully revived adult Caenorhabditis elegans preserved at -196°C using HIFU rewarming.
• Demonstrated that HIFU effectively avoids the problem of recrystallization during the rewarming process.
• Confirmed the scalability of HIFU technology for rewarming applications.

Conclusions:

• High Intensity Focused Ultrasound (HIFU) is a promising technology for rapid and uniform rewarming in cryopreservation.
• HIFU can overcome the challenge of recrystallization, enabling the cryopreservation of larger biological samples.
• This technology, potentially combined with other heating methods, opens new avenues for long-term storage of biological materials.