TY  - JOUR
A1  - Xu, Jietao
A1  - Fahmy-Garcia, Shorouk
A1  - Wesdorp, Marinus A.
A1  - Kops, Nicole
A1  - Forte, Lucia
A1  - De Luca, Claudio
A1  - Misciagna, Massimiliano Maraglino
A1  - Dolcini, Laura
A1  - Filardo, Giuseppe
A1  - Labberté, Margot
A1  - Vancíková, Karin
A1  - Kok, Joeri
A1  - van Rietbergen, Bert
A1  - Nickel, Joachim
A1  - Farrell, Eric
A1  - Brama, Pieter A. J.
A1  - van Osch, Gerjo J. V. M.
T1  - Effectiveness of BMP-2 and PDGF-BB adsorption onto a collagen/collagen-magnesium-hydroxyapatite scaffold in weight-bearing and non-weight-bearing osteochondral defect bone repair: in vitro, ex vivo and in vivo evaluation
JF  - Journal of Functional Biomaterials
N2  - Despite promising clinical results in osteochondral defect repair, a recently developed bi-layered collagen/collagen-magnesium-hydroxyapatite scaffold has demonstrated less optimal subchondral bone repair. This study aimed to improve the bone repair potential of this scaffold by adsorbing bone morphogenetic protein 2 (BMP-2) and/or platelet-derived growth factor-BB (PDGF-BB) onto said scaffold. The in vitro release kinetics of BMP-2/PDGF-BB demonstrated that PDGF-BB was burst released from the collagen-only layer, whereas BMP-2 was largely retained in both layers. Cell ingrowth was enhanced by BMP-2/PDFG-BB in a bovine osteochondral defect ex vivo model. In an in vivo semi-orthotopic athymic mouse model, adding BMP-2 or PDGF-BB increased tissue repair after four weeks. After eight weeks, most defects were filled with bone tissue. To further investigate the promising effect of BMP-2, a caprine bilateral stifle osteochondral defect model was used where defects were created in weight-bearing femoral condyle and non-weight-bearing trochlear groove locations. After six months, the adsorption of BMP-2 resulted in significantly less bone repair compared with scaffold-only in the femoral condyle defects and a trend to more bone repair in the trochlear groove. Overall, the adsorption of BMP-2 onto a Col/Col-Mg-HAp scaffold reduced bone formation in weight-bearing osteochondral defects, but not in non-weight-bearing osteochondral defects.
KW  - tissue engineering
KW  - regenerative medicine
KW  - osteochondral lesion
KW  - biocompatible materials
KW  - bone morphogenetic proteins
KW  - platelet-derived growth factor
KW  - animal model
KW  - weight-bearing
Y1  - 2023
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-304019
SN  - 2079-4983
VL  - 14
IS  - 2
ER  - 
TY  - JOUR
A1  - Castilho, Miguel
A1  - Hochleitner, Gernot
A1  - Wilson, Wouter
A1  - van Rietbergen, Bert
A1  - Dalton, Paul D.
A1  - Groll, Jürgen
A1  - Malda, Jos
A1  - Ito, Keita
T1  - Mechanical behavior of a soft hydrogel reinforced with three-dimensional printed microfibre scaffolds
JF  - Scientific Reports
N2  - Reinforcing hydrogels with micro-fibre scaffolds obtained by a Melt-Electrospinning Writing (MEW) process has demonstrated great promise for developing tissue engineered (TE) constructs with mechanical properties compatible to native tissues. However, the mechanical performance and reinforcement mechanism of the micro-fibre reinforced hydrogels is not yet fully understood. In this study, FE models, implementing material properties measured experimentally, were used to explore the reinforcement mechanism of fibre-hydrogel composites. First, a continuum FE model based on idealized scaffold geometry was used to capture reinforcement effects related to the suppression of lateral gel expansion by the scaffold, while a second micro-FE model based on micro-CT images of the real construct geometry during compaction captured the effects of load transfer through the scaffold interconnections. Results demonstrate that the reinforcement mechanism at higher scaffold volume fractions was dominated by the load carrying-ability of the fibre scaffold interconnections, which was much higher than expected based on testing scaffolds alone because the hydrogel provides resistance against buckling of the scaffold. We propose that the theoretical understanding presented in this work will assist the design of more effective composite constructs with potential applications in a wide range of TE conditions.
KW  - biomedical engineering
KW  - biomedical materials
KW  - gels and hydrogels
Y1  - 2018
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-222280
VL  - 8
ER  -