Effect of 'in air' freezing on post-thaw recovery of Callithrix jacchus mesenchymal stromal cells and properties of 3D collagen-hydroxyapatite scaffolds.

Through enabling an efficient supply of cells and tissues in the health sector on demand, cryopreservation is increasingly becoming one of the mainstream technologies in rapid translation and commercialization of regenerative medicine research. Cryopreservation of tissue-engineered constructs (TECs) is an emerging trend that requires the development of practically competitive biobanking technologies. In our previous studies, we demonstrated that conventional slow-freezing using dimethyl sulfoxide (MeSO) does not provide sufficient protection of mesenchymal stromal cells (MSCs) frozen in 3D collagen-hydroxyapatite scaffolds.

Central Growth Factor Loaded Depots in Bone Tissue Engineering Scaffolds for Enhanced Cell Attraction.

Tissue engineering, the application of stem and progenitor cells in combination with an engineered extracellular matrix, is a promising strategy for bone regeneration. However, its success is limited by the lack of vascularization after implantation. The concept of in situ tissue engineering envisages the recruitment of cells necessary for tissue regeneration from the host environment foregoing ex vivo cell seeding of the scaffold.

Design and Fabrication of Complex Scaffolds for Bone Defect Healing: Combined 3D Plotting of a Calcium Phosphate Cement and a Growth Factor-Loaded Hydrogel.

Additive manufacturing enables the fabrication of scaffolds with defined architecture. Versatile printing technologies such as extrusion-based 3D plotting allow in addition the incorporation of biological components increasing the capability to restore functional tissues. We have recently described the fabrication of calcium phosphate cement (CPC) scaffolds by 3D plotting of an oil-based CPC paste under mild conditions.

The effect of SDF-1α on low dose BMP-2 mediated bone regeneration by release from heparinized mineralized collagen type I matrix scaffolds in a murine critical size bone defect model.

The treatment of critical size bone defects represents a challenge. The growth factor bone morphogenetic protein 2 (BMP-2) is clinically established but has potentially adverse effects when used at high doses. The aim of this study was to evaluate if stromal derived factor-1 alpha (SDF-1α) and BMP-2 released from heparinized mineralized collagen type I matrix (MCM) scaffolds have a cumulative effect on bone regeneration.

Impact of acetylcholine and nicotine on human osteoclastogenesis in vitro.

Recent studies showed that the non-neuronal cholinergic system (NNCS) is taking part in bone metabolism. Most studies investigated its role in osteoblasts, but up to now, the involvement of the NNCS in human osteoclastogenesis remains relatively unclear. Thus, aim of the present study was to determine whether the application of acetylcholine (ACh, 10(−4) M), nicotine (10(−6) M), mineralized collagen membranes or brain derived neurotrophic factor (BDNF, 40 ng/mL) influences the mRNA regulation of molecular components of the NNCS and the neurotrophin family during osteoclastogenesis.

Quantification of calcium content in bone by using ToF-SIMS--a first approach.

The determination of the spatially resolved calcium distribution and concentration in bone is essential for the assessment of bone quality. It enables the diagnosis and elucidation of bone diseases, the course of bone remodelling and the assessment of bone quality at interfaces to implants. With time-of-flight secondary ion mass spectrometry (ToF-SIMS) the calcium distribution in bone cross sections is mapped semi-quantitatively with a lateral resolution of up to 1 μm.

Heparinization of a biomimetic bone matrix: integration of heparin during matrix synthesis versus adsorptive post surface modification.

This study intended to evaluate a contemporary concept of scaffolding in bone tissue engineering in order to mimic functions of the extracellular matrix. The investigated approach considered the effect of the glycosaminoglycan heparin on structural and biological properties of a synthetic biomimetic bone graft material consisting of mineralized collagen. Two strategies for heparin functionalization were explored in order to receive a three-component bone substitute material.

Heparin modification of a biomimetic bone matrix for controlled release of VEGF.

Bone regeneration using tissue engineered constructs requires strategies to effectively stimulate vascularization within such a construct that is crucial for its supply and integration with the host tissue. In this work, porous scaffolds of a collagen/hydroxyapatite nanocomposite were modified with heparin to generate biomimetic bone matrices which are able to release angiogenic factors in a controlled manner. Heparin was either integrated during material synthesis (in situ) or added to the scaffolds after their fabrication (post).