Closed Vitrification System as A Platform for Cryopreservation of Tissue Engineered Constructs.

Area of Science:

• Regenerative Medicine
• Biotechnology
• Cell Biology

Background:

• Cryopreservation of mesenchymal stromal cells (MSCs) and MSCs-based tissue engineered constructs (TECs) is crucial for regenerative medicine.
• Developing effective cryopreservation methods ensures the long-term viability and therapeutic potential of these cells and constructs.

Purpose of the Study:

• To evaluate a vitrification system for cryopreserving MSCs-based TECs.
• The system comprises a multicomponent vitreous solution, a closed container, human adult MSCs, and a two-step exposure procedure.

Main Methods:

• Vitrification properties were assessed using visual analysis and calorimetry.
• Cell viability, metabolic activity, and adhesion were measured post-exposure and after cooling-thawing.
• The system was tested on MSC suspensions (S-MSCs) and alginate-encapsulated MSCs (AE-MSCs).

Main Results:

• Minimal cryoprotectant concentrations for ice-free vitrification were identified (e.g., 10% DMSO, 20% EG, 20% 1,2-PD, 0.5 M sucrose).
• Extended exposure time in vitreous solution improved AE-MSCs viability and metabolic activity to levels comparable to S-MSCs.
• Vitrified MSCs retained osteogenic and adipogenic differentiation capacities.

Conclusions:

• The developed vitrification system shows promise as a platform for cryopreserving MSCs-based TECs.
• This system can facilitate the development of robust protocols for MSCs-based regenerative medicine therapies.