Cryopreserved Spontaneous Spheroids from Compact Bone-Derived Mesenchymal Stromal Cells for Bone Tissue Engineering

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Stem Cell Biology

Background:

• Mesenchymal stromal cells (MSCs) are crucial for bone regeneration.
• Spontaneously formed MSC spheroids exhibit enhanced stemness and plasticity.
• Cryopreservation is essential for the clinical application of cell-based therapies.

Purpose of the Study:

• To investigate the impact of cryopreservation on the viability, stemness, and osteogenic differentiation of spontaneous mouse compact bone-derived MSC spheroids (CB-MSC spheroids).
• To evaluate the in vivo bone-forming capacity of cryopreserved CB-MSC spheroids.

Main Methods:

• CB-MSCs were isolated and cultured to form spontaneous spheroids.
• Spheroids were cryopreserved using varying concentrations of dimethyl sulfoxide (DMSO).
• Cell viability, stem cell marker expression, osteogenic gene expression, and in vivo bone formation were assessed post-thaw.

Main Results:

• Optimal viability was achieved with 5% DMSO cryopreservation.
• Stemness and osteogenic differentiation potential were preserved post-cryopreservation with 5% DMSO.
• Cryopreserved spheroids demonstrated significant in vivo bone formation, comparable to non-cryopreserved controls.

Conclusions:

• Cryopreservation with 5% DMSO effectively preserves the biological properties of spontaneous CB-MSC spheroids.
• Cryopreserved CB-MSC spheroids are viable and functional for bone tissue engineering applications.
• These findings highlight the potential of cryopreserved spontaneous CB-MSC spheroids as off-the-shelf therapeutic products.