TY  - JOUR
A1  - Schneider, Tobias
A1  - Kohl, Benjamin
A1  - Sauter, Tilman
A1  - Kratz, Karl
A1  - Lendlein, Andreas
A1  - Ertel, Wolfgang
A1  - Schulze-Tanzil, Gundula
T1  - Influence of fiber orientation in electrospun polymer scaffolds on viability, adhesion and differentiation of articular chondrocytes
JF  - Clinical hemorheology and microcirculation : blood flow and vessels
N2  - Degradable polymers with a tailorable degradation rate might be promising candidate materials for biomaterial-based cartilage repair. In view of the poor intrinsic healing capability of cartilage, implantation of autologous chondrocytes seeded on a biocompatible slow degrading polymer might be an encouraging approach to improve cartilage repair in the future. This study was undertaken to test if the fiber orientation (random versus aligned) of two different degradable polymers and a polymer intended for long term applications could influence primary articular chondrocytes growth and ultrastructure.
 A degradable copoly(ether) esterurethane (PDC) was synthesized via co-condensation of poly(p-dioxanone) diol and poly(epsilon-caprolactone) diol using an aliphatic diisocyanate as linker. Poly(p-dioxanone) (PPDO) was applied as commercially available degradable polymer, while polyetherimide (PEI) was chosen as biomaterial enabling surface functionalization. The fibrous scaffolds of PDC and PPDO were obtained by electrospinning using 1,1,1,3,3,3 hexafluoro-2-propanol (HFP), while for PEI dimethyl acetamide (DMAc) was applied as solvent. Primary porcine articular chondrocytes were seeded at different cell densities on the fibrous polymer scaffolds and analyzed for viability (fluorescein diacetate/ethidiumbromide staining), for type II collagen synthesis (immunolabelling), ultrastructure and orientation on the fibers (SEM: scanning electron microscopy).
 Vital chondrocytes adhered on all electrospun scaffolds irrespective of random and aligned topologies. In addition, the chondrocytes produced the cartilage-specific type II collagen on all tested polymer topologies suggesting their differentiated functions. SEM revealed an almost flattened chondrocytes shape on scaffolds with random fiber orientation: whereby chondrocytes growth remained mainly restricted to the scaffold surface. On aligned fibers the chondrocytes exhibited a more spindle-shaped morphology with rougher cell surfaces but only a minority of the cells aligned according to the fibers. As a next step the reduction of the fiber diameter of electrospun scaffolds should be addressed as an important parameter to mimic cartilage ECM structure.
KW  - Chondrocytes
KW  - electrospinning
KW  - scaffold
KW  - differentiation
KW  - multiblock copolymer
Y1  - 2012
U6  - https://doi.org/10.3233/CH-2012-1608
SN  - 1386-0291
VL  - 52
IS  - 2-4
SP  - 325
EP  - 336
PB  - IOS Press
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Peng, Tao
A1  - Zhu, Ganghua
A1  - Dong, Yunpeng
A1  - Zeng, Junjie
A1  - Li, Wei
A1  - Guo, Weiwei
A1  - Chen, Yong
A1  - Duan, Maoli
A1  - Hocher, Berthold
A1  - Xie, Dinghua
T1  - BMP4: a possible key factor in differentiation of auditory neuron-like cells from bone-derived mesenchymal stromal cells
JF  - Clinical laboratory : the peer reviewed journal for clinical laboratories and laboratories related to blood transfusion
N2  - Background: Previous studies have shown that BMP4 may play an important part in the development of auditory neurons (ANs), which are degenerated in sensorineural hearing loss. However, whether BMP4 can promote sensory fate specification from mesenchymal stromal cells (MSCs) is unknown so far.
 Methods: MSCs isolated from Sprague-Dawley (SD) rats were confirmed by expression of MSC markers using flow cytometry and adipogenesis/osteogenesis using differentiation assays. MSCs treated with a complex of neurotrophic factors (BMP4 group and non-BMP4 group) were induced into auditory neuron-like cells, then the differences between the two groups were analyzed in morphological observation, cell growth curve, qRT-PCR, and immunofluorescence.
 Results: Flow cytometric analysis showed that the isolated cells expressed typical MSC surface markers. After adipogenic and osteogenic induction, the cells were stained by oil red O and Alizarin Red. The neuronal induced cells were in the growth plateau and had special forms of neurons. In the presence of BMP4, the inner ear genes NF-M, Neurog1, GluR4, NeuroD, Calretinin, NeuN, Tau, and GATA3 were up-regulated in MSCs.
 Conclusions: MSCs have the capacity to differentiate into auditory neuron-like cells in vitro. As an effective inducer, BMP4 may play a key role in transdifferentiation.
KW  - differentiation
KW  - auditory neurons
KW  - BMP4
Y1  - 2015
U6  - https://doi.org/10.7754/Clin.Lab.2015.150217
SN  - 1433-6510
VL  - 61
IS  - 9
SP  - 1171
EP  - 1178
PB  - Clin Lab Publ., Verl. Klinisches Labor
CY  - Heidelberg
ER  -