Injectable gel graft for bone defect repair

Regen Med. 2014 Jan;9(1):41-51. doi: 10.2217/rme.13.76.


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.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Bone Morphogenetic Protein 2 / metabolism*
  • Bone Regeneration / drug effects
  • Bone Regeneration / physiology*
  • Bone Transplantation / methods*
  • Gels / administration & dosage
  • Gels / therapeutic use*
  • Injections / methods
  • Mice
  • NIH 3T3 Cells
  • Rats
  • Skull / pathology*


  • Bmp2 protein, mouse
  • Bone Morphogenetic Protein 2
  • Gels