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Feng Y.-F.,PLA Fourth Military Medical University | Wang L.,PLA Fourth Military Medical University | Zhang Y.,PLA Fourth Military Medical University | Li X.,Shanghai JiaoTong University | And 4 more authors.
Biomaterials | Year: 2013

Clinical evidence indicates diabetes as a majorrisk factor for titaniumimplant treatment with high failure rates and poor osteointegration, but the underlying mechanism involved remains elusive.We hypothesize that reactive oxygen species (ROS) overproduction may contribute to the impaired osteogenesis of porous titanium implants (pTi) under diabetic conditions. To test this hypothesis, we culturedprimary rabbit osteoblasts onto pTi and studied the cellular performance when subjected to normal serum (NS), diabetic serum (DS), DS + NAC (a potent ROS inhibitor) and NS + H2O2(an oxidant).In-vivo performance of pTi was investigated by transplanting them intofemoral condyledefects of diabetic rabbits, which received vehicle or NAC treatment respectively.Results showed that diabetic conditions induced significant cellular apoptosis, depressedosteoblast function evidenced by impairedcell attachment and morphology, decreased cell proliferation anddifferentiation, andcompromised in-vivo osteogenesis ofpTi, while cellular ROSgeneration was increased derived from mitochondrial dysfunction. Scavenging ROS with NAC markedly attenuated cell apoptosis and osteoblast dysfunction, and improved bone ingrowth within pTi. Furthermore, treatment withH2O2 exerted similar adverse effect on cellular behavior as diabetes. This study furthers our knowledge on the potential role of ROS overproduction in the diabetes-induced impaired osteogenesis of titanium implants, and indicates anti-oxidative treatment as a promising strategy to promote the treatment efficacy of pTi in diabetic patients. © 2012 Elsevier Ltd.


Ding C.,Shanghai JiaoTong University | Qiao Z.,Shanghai JiaoTong University | Jiang W.,Shanghai Key Laboratory of Tissue Engineering | Li H.,Shanghai JiaoTong University | And 2 more authors.
Biomaterials | Year: 2013

Tissue engineering is considered as a promising approach for the regeneration of biological joint theoretically and thus provides a potential treatment option for advanced osteoarthritis. However, no significant progresses so far have been made in regenerating biological joint. In this study, a biphasic scaffold, which was consisted of polylactic acid-coated polyglycolic acid (PGA/PLA) scaffold and poly-e{open}-caprolactone/hydroxyapatite (PCL/HA) scaffold, was designed and used for regeneration of goat femoral head. The content of PLA and HA was optimized to a proper ratio, thus the scaffolds could achieve appropriate stiffness which was more conducive to articular cartilage and bone regeneration respectively. Furthermore, computer-aided design and manufacturing (CAD/CAM) technology was employed to fabricate the biphasic scaffolds into the desired shape and structure. The biphasic scaffolds with fine cell biocompatibility matched perfectly. Chondrocytes and bone marrow stromal cells (BMSCs) were seeded into the scaffolds for cartilage and bone regeneration respectively. After 10 weeks of implantation in nude mice subcutaneously, the cell-scaffold constructs successfully regenerated goat femoral heads. The regenerated femoral heads presented a precise appearance in shape and size similar to that of native goat femoral heads with a smooth, continuous, avascular, and homogeneous cartilage layer on the surface and stiff bone-like tissue in the microchannels of PCL/HA scaffold. Additionally, histological examination of the regenerated cartilage and bone showed typical histological structures and biophysical properties similar to that of native ones with specific matrix deposition and a well-integrated osteochondral interface. The strategy established in the study provides a promising approach for regenerating a biological joint which could be used to reconstruct the impaired joint. © 2013 Elsevier Ltd.


Li P.,Shanghai JiaoTong University | Yin Z.,Shanghai Key Laboratory of Tissue Engineering | Dou X.-Q.,Shanghai JiaoTong University | Zhou G.,Shanghai Key Laboratory of Tissue Engineering | Feng C.-L.,Shanghai JiaoTong University
ACS Applied Materials and Interfaces | Year: 2014

A convenient three-dimensional cell culture was developed by employing high swelling property of hybrid hydrogels coassembled from C2-phenyl- based supermolecular gelators and sodium hyaluronate. Imaging and spectroscopic analysis by scanning electron microscopy (SEM), atomic force microscopy (AFM), transform infrared (FT-IR) spectra confirm that the hybrid gelators can self-assemble into nanofibrous hydrogel. The high swelling property of dried gel ensures cell migration and proliferation inside bulk of the hydrogels, which provides a facial method to study disease models, the effect of drug dosages, and tissue culture in vitro. © 2014 American Chemical Society.


Zheng R.,Shanghai Key Laboratory of Tissue Engineering | Duan H.,Shanghai Key Laboratory of Tissue Engineering | Xue J.,Wenzhou Medical College | Liu Y.,Shanghai Key Laboratory of Tissue Engineering | And 8 more authors.
Biomaterials | Year: 2014

Scaffolds play an important role in directing three-dimensional (3-D) cartilage regeneration. Our recent study reported the potential advantages of electrospun gelatin/polycaprolactone (GT/PCL) membranes in regenerating 3-D cartilage. However, it is still unknown whether the changes of GT/PCL ratio have significant influence on 3-D cartilage regeneration. To address this issue, the current study prepared three kinds of electrospun membranes with different GT/PCL ratios (70:30, 50:50, 30:70). Adhesion and proliferation of chondrocytes on the membranes were examined to evaluate biocompatibility of the membranes. Cartilage with different 3-D shapes was engineered to further evaluate the influences of GT/PCL ratio on cartilage regeneration. The current results demonstrated that all the membranes with different GT/PCL ratios presented good biocompatibility with chondrocytes. Nevertheless, the high PCL content in the membranes significantly hampered early 3-D cartilage formation at 3 weeks invivo. Unexpectedly, at 12 weeks, all the cylinder-shaped constructs formed mature cartilage-like tissue with no statistical differences among groups. To our surprise, ear-shaped cartilage regeneration obtained quite different results again: the high PCL content completely disrupted cartilage regeneration even at 12 weeks, and only the least PCL content group formed homogeneous and continuous cartilage with a satisfactory shape and elasticity similar to human ear. All these results indicated that the high PCL content was unfavorable for 3-D cartilage regeneration, especially for the cartilage with a complicated shape, and that GT/PCL 70:30 might be a relatively suitable ratio for ear-shaped cartilage regeneration. The research models established in the current study provide detailed information for cartilage and other tissue regeneration based on electrospun GT/PCL membranes. © 2013 Elsevier Ltd.


Deng D.,Shanghai Key Laboratory of Tissue Engineering | Wang W.,Shanghai Key Laboratory of Tissue Engineering | Wang B.,Shanghai Key Laboratory of Tissue Engineering | Zhang P.,Donghua University | And 4 more authors.
Biomaterials | Year: 2014

Adipose derived stem cells (ASCs) are an important cell source for tissue regeneration and have been demonstrated the potential of tenogenic differentiation in vitro. This study explored the feasibility of using ASCs for engineered tendon repair in vivo in a rabbit Achilles tendon model. Total 30 rabbits were involved in this study. A composite tendon scaffold composed of an inner part of polyglycolic acid (PGA) unwoven fibers and an outer part of a net knitted with PGA/PLA (polylactic acid) fibers was used to provide mechanical strength. Autologous ASCs were harvested from nuchal subcutaneous adipose tissues and in vitro expanded. The expanded ASCs were harvested and resuspended in culture medium and evenly seeded onto the scaffold in the experimental group, whereas cell-free scaffolds served as the control group. The constructs of both groups were cultured inside a bioreactor under dynamic stretch for 5 weeks. In each of 30 rabbits, a 2 cm defect was created on right side of Achilles tendon followed by the transplantation of a 3 cm cell-seeded scaffold in the experimental group of 15 rabbits, or by the transplantation of a 3 cm cell-free scaffold in the control group of 15 rabbits. Animals were sacrificed at 12, 21 and 45 weeks post-surgery for gross view, histology, and mechanical analysis. The results showed that short term in vitro culture enabled ASCs to produce matrix on the PGA fibers and the constructs showed tensile strength around 50 MPa in both groups (p > 0.05). With the increase of implantation time, cell-seeded constructs gradually form neo-tendon and became more mature at 45 weeks with histological structure similar to that of native tendon and with the presence of bipolar pattern and D-periodic structure of formed collagen fibrils. Additionally, both collagen fibril diameters and tensile strength increased continuously with significant difference among different time points (p < 0.05). In contrast, cell-free constructs failed to form good quality tendon tissue with fibril structure observable only at 45 weeks. There were significant differences in both collagen fibril diameter and tensile strength between two groups at all examined time points (p < 0.05). The results of this study support that ASCs are likely to be a potential cell source for in vivo tendon engineering and regeneration. © 2014 Elsevier Ltd.


Huang J.,Shanghai Key Laboratory of Tissue Engineering | Lin X.,Shanghai Key Laboratory of Tissue Engineering | Shi Y.,Shanghai Key Laboratory of Tissue Engineering | Liu W.,Shanghai Key Laboratory of Tissue Engineering
Tissue Engineering - Part B: Reviews | Year: 2015

Tissue engineering and regenerative medicine (TERM) remains to be one of the fastest growing fields, which covers a wide scope of topics of both basic and applied biological researches. This overview article summarized the advancements in basic researches of TERM area, including stem cell biology, cell engineering, somatic nuclear transfer, genomic editing, discovery of new tissue progenitor/stem cells, and immunomodulation of stem cells and tissue regeneration. It reflects the cutting-edge achievements in basic researches, which will lay solid scientific foundation for future TERM translational researches. © 2015 Mary Ann Liebert, Inc.


Gong Y.Y.,Shanghai Key Laboratory of Tissue Engineering | Xue J.X.,Shanghai Key Laboratory of Tissue Engineering | Zhang W.J.,Shanghai Key Laboratory of Tissue Engineering | Zhou G.D.,Shanghai Key Laboratory of Tissue Engineering | And 2 more authors.
Biomaterials | Year: 2011

Acellular cartilage can provide a native extracellular matrix for cartilage engineering. However, it is difficult for cells to migrate into acellular cartilage because of its non-porous structure. The aim of this study is to establish a sandwich model for engineering cartilage with acellular cartilage sheets and chondrocytes. Cartilage from adult pig ear was cut into a circular cylinder with a diameter of approximately 6 mm and freeze-sectioned at thicknesses of 10 μm and 30 μm. The sheets were then decellularized and lyophilized. Chondrocytes isolated from newborn pig ear were expanded for 2 passages. The acellular sheets and chondrocytes were then stacked layer-by-layer, in a sandwich model, and cultured in dishes. After 4 weeks of cultivation, the constructs were then either maintained in culture for another 12 weeks or implanted subcutaneously in nude mouse. Histological analysis showed that cells were completely removed from cartilage sheets after decellularization. By re-seeding cells and stacking 20 layers of sheets together, a cylinder-shaped cell sheet was achieved. Cartilage-like tissues formed after 4 weeks of culture. Histological analyses showed the formation of cartilage with a typical lacunar structure. Cartilage formation was more efficient with 10 μm-thick sheets than with 30 μm sheets. Mature cartilage was achieved after 12 weeks of implantation, which was demonstrated by histology and confirmed by Safranin O, Toluidine blue and anti-type II collagen antibody staining. Furthermore, we achieved cartilage with a designed shape by pre-shaping the sheets prior to implantation. These results indicate that the sandwich model could be a useful model for engineering cartilage in vitro and in vivo. © 2010 Elsevier Ltd.


Bi D.,Shanghai Key Laboratory of Tissue Engineering | Chen F.G.,Shanghai Key Laboratory of Tissue Engineering | Zhang W.J.,Shanghai Key Laboratory of Tissue Engineering | Zhou G.D.,Shanghai Key Laboratory of Tissue Engineering | And 3 more authors.
BMC Cell Biology | Year: 2010

Background: We have previously obtained a clonal population of cells from human foreskin that is able to differentiate into mesodermal, ectodermal and endodermal progenies. It is of great interest to know whether these cells could be further differentiated into functional insulin-producing cells.Results: Sixty-one single-cell-derived dermal fibroblast clones were established from human foreskin by limiting dilution culture. Of these, two clones could be differentiated into neuron-, adipocyte- or hepatocyte-like cells under certain culture conditions. In addition, those two clones were able to differentiate into islet-like clusters under pancreatic induction. Insulin, glucagon and somatostatin were detectable at the mRNA and protein levels after induction. Moreover, the islet-like clusters could release insulin in response to glucose in vitro.Conclusions: This is the first study to demonstrate that dermal fibroblasts can differentiate into insulin-producing cells without genetic manipulation. This may offer a safer cell source for future stem cell-based therapies. © 2010 Bi et al; licensee BioMed Central Ltd.


Xue J.X.,Shanghai Key Laboratory of Tissue Engineering | Gong Y.Y.,Shanghai Key Laboratory of Tissue Engineering | Zhou G.D.,Shanghai Key Laboratory of Tissue Engineering | Liu W.,Shanghai Key Laboratory of Tissue Engineering | And 2 more authors.
Biomaterials | Year: 2012

Acellular cartilage sheets (ACSs) have been used as scaffolds for engineering cartilage with mature chondrocytes. In this study we investigated whether ACSs possess a chondrogenic induction activity that may benefit cartilage engineering with multipotent stem cells. Bone marrow-derived mesenchymal stem cells (BMSCs) isolated from newborn pigs were expanded in vitro and seeded on ACSs that were then stacked layer-by-layer to form BMSC-ACS constructs. Cells seeded on polyglycolic acid/polylactic acid (PGA/PLA) scaffolds served as a control. After 4 weeks of culture with or without additional chondrogenic factors, constructs were subcutaneously implanted into nude mice for another 4 weeks. Cartilage-like tissues were formed after 4 weeks of culture. However, formation of cartilage with a typical lacunar structure was only observed in induced groups. RT-PCR showed that aggrecan, COMP, type II collagen and Sox9 were expressed in all groups except the non-induced BMSC-PGA/PLA group. At 4 weeks post-implantation, cartilage formation was achieved in the induced BMSC-ACS group and partial cartilage formation was achieved in the non-induced BMSC-ACS group, confirmed by safranin O staining, toluidine blue staining and type II collagen immunostaining. In addition, enzyme-linked immunosorbent assay demonstrated the presence of transforming growth factor-β1, insulin-like growth factor-1 and bone morphogenic protein-2 in ACSs. These results indicate that ACSs possess a chondrogenic induction activity that promotes BMSC differentiation. © 2012 Elsevier Ltd.


Xue J.,Shanghai Key Laboratory of Tissue Engineering | Xue J.,Wenzhou Medical College | Feng B.,Donghua University | Zheng R.,Shanghai Key Laboratory of Tissue Engineering | And 6 more authors.
Biomaterials | Year: 2013

Tissue engineering approach continuously requires for emerging strategies to improve the efficacy in repairing and regeneration of tissue defects. Previously, we developed a sandwich model strategy for cartilage engineering, using the combination of acellular cartilage sheets (ACSs) and chondrocytes. However, the process for the preparation of ACSs is complicated, and it is also difficult to obtain large ACSs. The aim of this study was to engineer cartilage with precise three-dimensional (3-D) structures by applying electrospun fibrous membranes of gelatin/polycaprolactone (GT/PCL). We first prepared the electrospun GT/PCL membranes into rounded shape, and then seeded chondrocytes in the sandwich model. After in vitro and in vivo cultivation, the newly formed cartilage-like tissues were harvested. Macroscopic observations and histological analysis confirmed that the engineering of cartilage using the electrospun GT/PCL membranes was feasible. An ear-shaped cartilage was then constructed in the sandwich model, with the help of an ear-shaped titanium alloy mold. After 2 weeks of culture in vitro and 6 weeks of subcutaneous incubation in vivo, the ear-shaped cartilage largely maintained their original shape, with a shape similarity up to 91.41% of the titanium mold. In addition, the engineered cartilage showed good elasticity and impressive mechanical strength. These results demonstrated that the engineering of 3-D cartilage in a sandwich model using electrospun fibrous membranes was a facile and effective approach, which has the potential to be applied for the engineering of other tissues with complicated 3-D structures. © 2012 Elsevier Ltd.

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