• Home
  • Search Results
  • Toll-like receptor 4 mediates the regenerative effects of bone grafts for calvarial bone repair.

Toll-like receptor 4 mediates the regenerative effects of bone grafts for calvarial bone repair.

Tissue engineering. Part A (2015-01-22)
Dan Wang, James R Gilbert, Melissa A Shaw, Sameer Shakir, Joseph E Losee, Timothy R Billiar, Gregory M Cooper
ABSTRACT

Craniofacial trauma is difficult to repair and presents a significant burden to the healthcare system. The inflammatory response following bone trauma is critical to initiate healing, serving to recruit inflammatory and progenitor cells and to promote angiogenesis. A role for inflammation in graft-induced bone regeneration has been suggested, but is still not well understood. The current study assessed the impact of Toll-like receptor (TLR4) signaling on calvarial repair in the presence of morselized bone components. Calvarial defects in wild-type and global TLR4(-/-) knockout mouse strains were treated with fractionated bone components in the presence or absence of a TLR4 neutralizing peptide. Defect healing was subsequently evaluated over 28 days by microcomputed tomography and histology. The matrix-enriched fraction of morselized bone stimulated calvarial bone repair comparably with intact bone graft, although the capacity for grafts to induce calvarial bone repair was significantly diminished by inhibition or genetic ablation of TLR4. Overall, our findings suggest that the matrix component of bone graft stimulates calvarial bone repair in a TLR4-dependent manner. These results support the need to better understand the role of inflammation in the design and implementation of strategies to improve bone healing.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
Propidium iodide, ≥94.0% (HPLC)
Sigma-Aldrich
Propidium iodide solution, solution (1.0 mg/ml in water)
Sigma-Aldrich
Ethyl alcohol, Pure, 200 proof, meets USP testing specifications
Sigma-Aldrich
o-Xylene, anhydrous, 97%
Sigma-Aldrich
o-Xylene, puriss. p.a., ≥99.0% (GC)
Sigma-Aldrich
o-Xylene, reagent grade, ≥98.0%
Supelco
o-Xylene, analytical standard
Sigma-Aldrich
Propidium iodide, ≥94% (HPLC)
Supelco
Ethanol solution, certified reference material, 2000 μg/mL in methanol
Supelco
o-Xylene, suitable for HPLC, 98%
Supelco
o-Xylene, Pharmaceutical Secondary Standard; Certified Reference Material
Sigma-Aldrich
Ethanol, absolute, denaturated with 0.5-1.5 Vol.% 2-butanone and approx. 0.001% Bitrex (GC), ≥98% (GC)