Poor vascularization is the key limitation for long-term acceptance of large three-dimensional (3D) tissue engineering constructs in regenerative medicine. 45S5 Bioglass Ò was investigated given its potential for applications in bone engineering. Since native Bioglass Ò shows insufficient angiogenic properties, we used a collagen coating, to seed human adipose tissue-derived stem cells (hASC) confluently onto 3D 45S5 Bioglass Ò -based scaffolds. To investigate vascularization by semiquantitative analyses, these biofunctionalized scaffolds were then subjected to in vitro human umbilical vein endothelial cells formation assays, and were also investigated in the chorioallantoic membrane (CAM) angiogenesis model, an in vivo angiogenesis assay, which uses the CAM of the hen's egg. In their native, nonbiofunctionalized state, neither Bioglass Ò -based nor biologically inert fibrous polypropylene control scaffolds showed angiogenic properties. However, significant vascularization was induced by hASC-seeded scaffolds (Bioglass Ò and polypropylene) in the CAM angiogenesis assay. Biofunctionalized scaffolds also showed enhanced tube lengths, compared to unmodified scaffolds or constructs seeded with fibroblasts. In case of biologically inert hernia meshes, the quantification of vascular endothelial growth factor secretion as the key angiogenic stimulus strongly correlated to the tube lengths and vessel numbers in all models. This correlation proved the CAM angiogenesis assay to be a suitable semiquantitative tool to characterize angiogenic effects of larger 3D implants. In addition, our results suggest that combinations of suitable scaffold materials, such as 45S5 Bioglass Ò , with hASC could be a promising approach for future tissue engineering applications.

Automated point-of-care testing system for rapid single cell detection of MRSA directly from nasal swab samples.

The test procedure described here may be a tool to evaluate the fabric feel with the exclusion of subjective biases.

Adipose tissue engineering, instead of tissue substitution, often uses autologous adipose tissue-derived stem cells (hASC). These cells are known to improve graft integration and to support neovascularization of scaffolds when seeded onto biomaterials. In this study we thought to engineer adipose tissue using scaffold-bound hASC, since they can be differentiated into the adipocyte cell lineage and used for soft tissue regeneration. We show here by microscopy and gene expression of the peroxysome proliferator-activated receptor gene (PPARγ2) that hASC growing on polypropylene fibrous scaffolds as well as on three-dimensional nonwoven scaffolds can be turned into adipose tissue within 19 days. Freshly isolated hASC displayed a higher differentiation potential than hASC cultured for eight passages. In addition, we proved a modified alginate microcapsule to directly induce adipogenic differentiation of incorporated hASC. The results may help to improve long-term success of adipose tissue regeneration, especially for large-scale soft tissue defects, and support the development of cell-scaffold combinations which can be shaped individually and directly induce the adipogenic differentiation of incorporated hASC at the site of implantation.

No abstract