Three-Dimensional Scaffolds for Tissue Engineering: The Importance of Uniformity in Pore Size and Structure

Department of Biomedical Engineering, Washington University, St. Louis, Missouri 63130, United States.
Langmuir (Impact Factor: 4.46). 12/2010; 26(24):19001-6. DOI: 10.1021/la104206h
Source: PubMed


To validate the importance of uniformity in pore size and structure of a scaffold for tissue engineering, we fabricated two types of scaffolds with uniform (inverse opal scaffolds) and nonuniform pore sizes and structures, and then evaluated their properties in terms of diffusion of macromolecules, spatial distribution of fibroblasts, and differentiation of preosteoblasts. Our results confirmed the superior performance of the inverse opal scaffolds due to the uniform pore size, homogeneous environment, and high interconnectivity: a higher diffusion rate, a uniform distribution of cells, and a higher degree of differentiation. In addition, we found that both the differentiation of cells and secretion of extracellular matrix were dependent on the properties of the individual pore to which the cells were attached, rather than the bulk properties of a scaffold. Our results clearly indicate that inverse opal scaffolds could provide a better microenvironment for cells in comparison to a scaffold with nonuniform size and structure.

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    • "diffusion rates and a more uniform distribution of cells in comparison to a scaffold with non-uniform size and structure (Choi et al., 2010). The cultivation of dFbs for 7 days (our unpublished data) and of bovine chondrocytes for 14 days (Hacker et al., 2007) in uncoated PLGA scaffolds showed a homogeneous distribution of cells and GAG synthesis throughout the entire scaffold. "
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    • "There is also a need to model heterogeneously distributed properties and responses (cf. Ref. [51]), but fortunately this is simply an issue of numerics in solving more complex initial boundary value problems because the constitutive framework is defined point-wise and can easily address spatial and temporal heterogeneity. Failure, whether by stenosis, aneurysmal dilatation or frank rupture, is often local, hence this aspect must be considered carefully in design and quality control. "
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