Photoencapsulated-Mesenchymal Stromal Cells in Biodegradable Thiol-Acrylate Hydrogels Enhance Regeneration of Craniofacial Bone Tissue Defects

Abstract

Aim: This study investigated biodegradable thiol-acrylate hydrogels as stem cell carriers to facilitate cranial bone regeneration. Materials & methods: Two formulations of thiol-acrylate hydrogels (5 and 15 wt% Poly[ethylene glycol]-diacrylate [PEGDA] hydrogels) were used as stem cell carriers. Bone marrow mesenchymal stromal cells and dental pulp mesenchymal stromal cells were photoencapsulated and cultured in basal or osteogenic medium 3 days before the surgery. Using New Zealand White Rabbits, four defects (5 mm diameter and 2 mm thickness) were created and hydrogel scaffolds were implanted in each rabbit cranium for 6 weeks. Results & Conclusion: AlamarBlue assay showed increasing metabolic activity levels in 5 wt% PEGDA hydrogels than 15 wt% PEGDA hydrogels. Photoencapsulated-mesenchymal stromal cells in 15 wt% PEGDA hydrogels demonstrated significantly increasing alkaline phosphatase activity levels on day 7 compared with days 1 and 3. Histological diagnosis showed 5 wt% PEGDA hydrogels resulted in lower averaged residual gel areas than 15 wt% PEGDA hydrogel specimens and control groups 6 weeks postimplantation.

Keywords::

• biodegradation
• craniofacial bone
• PEGDA hydrogels
• stem cells
• thiol-acrylate
• tissue engineering

View correction statement:

Retraction: Photoencapsulated-mesenchymal stromal cells in biodegradable thiol-acrylate hydrogels enhance regeneration of craniofacial bone tissue defects

Acknowledgments

The authors would like to thank CC Lin, PhD for generously providing PEGDA hydrogel (Purdue University, Weldon School of Biomedical Engineering, IN, USA) and T Chu, DDS for helping with animal surgery (Indiana University, School of Dentistry, IN, USA).

Financial & competing interests disclosure

The authors would like to thank the Canadian Bureau of International Education for the financial support provided to the first author during his PhD study (OTT, Canada). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

Ethical conduct of research

The authors state that they have obtained appropriate institutional review board approval for this study from the Institutional Animal Care and Use Committee at Indiana University School of Dentistry.

Additional information

Funding

The authors would like to thank the Canadian Bureau of International Education for the financial support provided to the first author during his PhD study (OTT, Canada). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed. No writing assistance was utilized in the production of this manuscript.