Local Microarchitecture Affects Mechanical Properties of Deposited Extracellular Matrix for Osteonal Regeneration

Abstract

Multiple biomimetic approaches have been attempted to accelerate the regeneration of functional bone tissue. While most synthetic scaffolds are designed to mimic the architecture of trabecular bone, in the current study, cortical bone like extracellular matrix was regenerated in vitro within organized structures. Biphasic calcium phosphate (BCaP) and hydroxyapatite (HAp) scaffolds were developed with longitudinal microchannels (250 micrometers in diameter) that resembled native osteons in cortical bone. BCaP and HAp scaffolds had a compressive strength of 7.61 + or - 1.42 and 9.98 + or - 0.61 MPa respectively. The constructs were investigated in vitro to evaluate the organization and stiffness of the extracellular matrix (ECM) formed by human fetal osteoblasts (HFObs) cultured inside the microchannels. The ECM deposited on the BCaP scaffolds was found to have a higher micro hardness (h) (1.93 + or - 0.40 GPa) than the ECM formed within the HAp microchannels (h = 0.80 + or - 0.20 GPa) (p less than 0.05) or native bone(h = 0.47 0.74 GPa). ECM deposition within the microchannels resembled osteoid organization and showed a significant increase in both osteoid area and thickness after 24 days (p less than 0.001). These observations indicate that controlled microarchitecture, specifically cylindrical microchannels, plays a fundamental role in stimulating the appropriate cellular response aimed at recreating organized, cortical bone like matrix. These findings open the door for researchers to develop a new generation of cortical bone scaffolds that can restore strong, organized bone.

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Document Details

Document Type
Technical Report
Publication Date
Oct 31, 2013
Accession Number
ADA615214

Entities

People

  • B. E. Pollot
  • M. Pilia
  • M. R. Appleford
  • T. Guda
  • V. Aguero

Organizations

  • United States Army Institute of Surgical Research

Tags

Communities of Interest

  • Biomedical

DTIC Thesaurus Topics

  • Biomedical Engineering
  • Blood
  • Blood Vessels
  • Calcium Compounds
  • Cells
  • Cellular Structures
  • Chemistry
  • Compressive Strength
  • Computing System Architectures
  • Manufacturing
  • Material Degradation Processes
  • Materials
  • Materials Science
  • Mechanical Properties
  • Mechanical Working
  • Modulus Of Elasticity
  • Three Dimensional

Readers

  • Aerosol Science/Aerosol Physics
  • Immunology and Pathology
  • Trauma Surgery or Emergency Medicine.

Technology Areas

  • Biotechnology