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bioRxiv · 10.1101/691618

Mineral deposition and vascular invasion of hydroxyapatite reinforced collagen scaffolds seeded with human adipose-derived stem cells

Weiss-Bilka, H. E.·Meagher, M. J.·Gargac, J. A.·Niebur, G. L.·Roeder, R. K.·Wagner, D. R.
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Abstract

Collagen-based scaffolds reinforced with hydroxyapatite (HA) are an attractive choice for bone tissue engineering because their composition mimics that of bone. We previously reported the development of compression-molded collagen-HA scaffolds that exhibited high porosity, interconnected pores, and mechanical properties that were well-suited for surgical handling and fixation. The objective of this study was to investigate the use of these novel collagen-HA scaffolds in combination with human adipose-derived stem cells (hASCs) as a template for bone formation in a subcutaneous athymic mouse model. Cell-seeded constructs were pre-treated with either control or osteogenic media. Cell-free and collagen-only groups were included, as was a clinically approved bone void filler as a control for the material. After 8 weeks implantation, cell-free collagen-HA scaffolds and those that were pre-seeded with osteogenically differentiated hASCs supported bone formation and vascular invasion at comparable rates. HA-reinforcement allowed collagen constructs to maintain their implanted shape, provided for improved cell-tissue-scaffold integration, and resulted in a more organized tissue when pre-treated in an osteogenic induction medium. Scaffold type and pre-treatment also determined osteoclast activity and therefore potential remodeling of the constructs. Results suggest that it may be necessary to match the scaffold with a particular cell type and cell-specific pre-treatment to achieve optimal bone formation.

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Weiss-Bilka, H. E., Meagher, M. J., Gargac, J. A., Niebur, G. L., Roeder, R. K., Wagner, D. R.. 2019-07-03. Mineral deposition and vascular invasion of hydroxyapatite reinforced collagen scaffolds seeded with human adipose-derived stem cells. https://doi.org/10.1101/691618

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