Dataset Information

Bone Tissue Engineering with Multilayered Scaffolds-Part I: An Approach for Vascularizing Engineered Constructs In Vivo.

ABSTRACT: Obtaining functional capillaries through the bulk has been identified as a major challenge in tissue engineering, particularly for critical-sized defects. In the present study, a multilayered scaffold system was developed for bone tissue regeneration, designed for through-the-thickness vascularization of the construct. The basic principle of this approach was to alternately layer mesenchymal stem cell-seeded nanofibers (osteogenic layer) with microfibers or porous ceramics (osteoconductive layer), with an intercalating angiogenic zone between the two and with each individual layer in the microscale dimension (100-400??m). Such a design can create a scaffold system potentially capable of spatially distributed vascularization in the overall bulk tissue. In the cellular approach, the angiogenic zone consisted of collagen/fibronectin gel with endothelial cells and pericytes, while in the acellular approach, cells were omitted from the zone without altering the gel composition. The cells incorporated into the construct were analyzed for viability, distribution, and organization of cells on the layers and vessel development in vitro. Furthermore, the layered constructs were implanted in the subcutaneous space of nude mice and the processes of vascularization and bone tissue regeneration were followed by histological and energy-dispersive X-ray spectroscopy (EDS) analysis. The results indicated that the microenvironment in the angiogenic zone, microscale size of the layers, and the continuously channeled architecture at the interface were adequate for infiltrating host vessels through the bulk and vascularizing the construct. Through-the-thickness vascularization and mineralization were accomplished in the construct, suggesting that a suitably bioengineered layered construct may be a useful design for regeneration of large bone defects.

SUBMITTER: Sathy BN

PROVIDER: S-EPMC4605360 | biostudies-literature | 2015 Oct

REPOSITORIES: biostudies-literature

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Bone Tissue Engineering with Multilayered Scaffolds-Part I: An Approach for Vascularizing Engineered Constructs In Vivo.

Sathy Binulal Nelson BN Mony Ullas U Menon Deepthy D Baskaran V K VK Mikos Antonios G AG Nair Shantikumar S

Tissue engineering. Part A 20151001 19-20

Obtaining functional capillaries through the bulk has been identified as a major challenge in tissue engineering, particularly for critical-sized defects. In the present study, a multilayered scaffold system was developed for bone tissue regeneration, designed for through-the-thickness vascularization of the construct. The basic principle of this approach was to alternately layer mesenchymal stem cell-seeded nanofibers (osteogenic layer) with microfibers or porous ceramics (osteoconductive layer ...[more]

PMID: 26262757

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Dataset Information

Bone Tissue Engineering with Multilayered Scaffolds-Part I: An Approach for Vascularizing Engineered Constructs In Vivo.

Publications

Bone Tissue Engineering with Multilayered Scaffolds-Part I: An Approach for Vascularizing Engineered Constructs In Vivo.

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