Injectable Gel Graft for Bone Defect Repair

Abstract

Aim: To examine the performance of an injectable gel graft made of transglutaminase (Tg)-crosslinked gelatin gel with BMP-2 (BMP-2–Tg–Gel) for bone defect repair in animal models. Materials & methods: BMP-2 mixed with gelatin gel was crosslinked using Tg. The release of tethered BMP-2 through autocrine and paracrine pathways was demonstrated by using C2C12 and NIH 3T3 cells, respectively. BMP-2–Tg–Gel was injected into the induced cranial defect site. After 14 days, the sample was removed for x-ray imaging and histological evaluation. Results: Our in vivo results demonstrated that the injectable Tg–Gel with its osteoconductivity and controllable BMP-2 activity induced bone formation in our rat models when tethered with BMP-2. Conclusion: Tg–Gel as an injectable functional bone graft may enable the use of minimally invasive surgical procedures to treat irregular-shaped bone defects. Furthermore, this novel approach is capable of incorporating and controlling the release of therapeutic agents that may advance the science of tissue regeneration.

KEYWORDS::

• BMP-2 delivery
• bone defect repair
• gelatin gel
• injectable
• osteoconductive
• osteogenic
• transglutaminase

Disclaimer

The contents are solely the responsibility of the authors and do not necessarily represent the official view of the NIH.

Financial & competing interests disclosure

This project was supported by SC CTSI (NIHNCRR/NCATS) through grant UL1RR031986. 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 or have followed the principles outlined in the Declaration of Helsinki for all human or animal experimental investigations. In addition, for investigations involving human subjects, informed consent has been obtained from the participants involved.

Additional information

Funding

This project was supported by SC Chartered Trading Standards Institute CTSI (NIHNCRR/NCATS) through grant UL1RR031986. 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.