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Success of 3D tissue substitutes in clinical applications depends on the presence of vascular networks in their structure. Accordingly, research in tissue engineering is focused on the stimulation of angiogenesis or generation of a vascular network in the scaffolds prior to implantation. A novel, xeno-free, collagen/hyaluronic acid-based poly(L-lactide-co-?-caprolactone) (PLC/COL/HA) (20/9.5/0.5 w/w/w) microfibrous scaffold was produced by electrospinning. Collagen types I and III, and hyaluronic acid were isolated from human umbilical cords and blended with the GMP grade PLC. When compared with PLC scaffolds the PLC/COL/HA had higher water uptake capacity (103% vs 66%) which may have contributed to the decrease in its Young's Modulus (from 1.31 to 0.89 MPa). The PLC/COL/HA better supported adipose tissue-derived mesenchymal stem cell (AT MSC) adhesion; within 24 h the cell number on the PLC/COL/HA scaffolds was 3 fold higher. Co-culture of human umbilical vein endothelial cells and AT MSCs induced capillary formation on both scaffold types, but the PLC/COL/HA led to formation of interconnected vessels whose total length was 1.6 fold of the total vessel length on PLC. Clinical use of this scaffold would eliminate the immune response triggered by xenogeneic collagen and transmission of animal-borne diseases while promoting a better vascular network formation. © 2018 Elsevier B.V. 111T368 Türkiye Bilimsel ve Teknolojik AraÅ?tirma Kurumu This study was supported by The Scientific and Technological Research Council of Turkey (TUBITAK) (grant number 111T368 ). We thank Prof. Murat Kasap and Abula Ayimugu from Proteomics Lab at Kocaeli University Experimental and Clinical Research Center for their help in characterizing the collagen by SDS-PAGE gel electrophoresis. We thank the members of Plastics and Rubber Technology Research Lab at Kocaeli University Chemical Engineering Department for their help in FTIR analysis of the scaffolds and their components.

Success of 3D tissue substitutes in clinical applications depends on the presence of vascular networks in their structure. Accordingly, research in tissue engineering is focused on the stimulation of angiogenesis or generation of a vascular network in the scaffolds prior to implantation. A novel, xeno-free, collagen/hyaluronic acid-based poly(L-lactide-co-epsilon-caprolactone) (PLC/COL/HA) (20/9.5/0.5 w/w/w) microfibrous scaffold was produced by electrospinning. Collagen types I and III, and hyaluronic acid were isolated from human umbilical cords and blended with the GMP grade PLC. When compared with PLC scaffolds the PLC/COL/HA had higher water uptake capacity (103% vs 66%) which may have contributed to the decrease in its Young's Modulus (from 1.31 to 0.89 MPa). The PLC/COL/HA better supported adipose tissue-derived mesenchymal stem cell (AT MSC) adhesion; within 24 h the cell number on the PLC/COL/HA scaffolds was 3 fold higher. Co-culture of human umbilical vein endothelial cells and AT MSCs induced capillary formation on both scaffold types, but the PLC/COL/HA led to formation of interconnected vessels whose total length was 1.6 fold of the total vessel length on PLC. Clinical use of this scaffold would eliminate the immune response triggered by xenogeneic collagen and transmission of animal-borne diseases while promoting a better vascular network formation. Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [111T368] This study was supported by The Scientific and Technological Research Council of Turkey (TUBITAK) (grant number 111T368). We thank Prof. Murat Kasap and Abula Ayimugu from Proteomics Lab at Kocaeli University Experimental and Clinical Research Center for their help in characterizing the collagen by SDS-PAGE gel electrophoresis. We thank the members of Plastics and Rubber Technology Research Lab at Kocaeli University Chemical Engineering Department for their help in FTIR analysis of the scaffolds and their components.

The main objective was to study cartilage regeneration through differentiation of human tooth germ stem cells (HTGSCs) into chondrocytes on different three-dimensional (3D) scaffolds (PCL, PLLA and PCL–PLLA). Scaffold topographies were studied by scanning electron microscopy and it was found that the scaffolds had interconnected macroporous structures. HTGSCs were isolated from impacted third molar tooth germs of young adult patients and grown for 3 weeks on the scaffolds in chondrogenic differentiation medium. Cell proliferation on the scaffolds was determined by MTS assay and it was observed that all scaffolds supported cell proliferation. Immunostaining was carried out for morphological and differentiation analyses. Immunohistochemical analyses revealed that the cells attached onto the scaffolds and deposited cartilage-specific extracellular matrix (ECM). Real-time PCR was performed to determine the expression levels of cartilage-specific genes. After 21 days of incubation in cartilage differentiation medium, expression of collagen type II increased only in the cells seeded onto PCL–PLLA blend scaffolds. Similarly, aggrecan expression was the highest on PCL–PLLA scaffolds after 3 weeks. These results suggest that all the scaffolds, and especially PCL–PLLA, were suitable for chondrogenic differentiation of HTGSCs. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

Co-culture of bone forming cells and endothelial cells to induce pre-vascularization is one of the strategies used to solve the insufficient vascularization problem in bone tissue engineering attempts. In the study, primary cells isolated from 2 different tissues of the same animal, rat bone marrow stem cells (RBMSCs) and rat aortic endothelial cells (RAECs) were co-cultured to study the effects of co-culturing on both osteogenesis and angiogenesis. The formation of tube like structure in 2D culture was observed for the first time in the literature by the co-culture of primary cells from the same animal and also osteogenesis and angiogenesis were investigated at the same time by using this co-culture system. Co-cultured cells mineralized and formed microvasculature beginning from 14 days of incubation. After 28 days of incubation in the osteogenic medium, expression of osteogenic genes in co-cultures was significantly upregulated compared to RBMSCs cultured alone. These results suggest that the co-culture of endothelial cells with mesenchymal stem cells induces both osteogenesis and angiogenesis. © 2016 Elsevier Inc. Türkiye Bilimsel ve Teknolojik AraÅ?tirma Kurumu Consumables and reagents for this study were funded by Yeditepe University, İstanbul, Turkey. G. G. Pekozer acknowledges the support from TÜBİTAK (The Scientific and Technological Research Council of Turkey) during her MSc. and PhD. education. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

The main objective was to study cartilage regeneration through differentiation of human tooth germ stem cells (HTGSCs) into chondrocytes on different three-dimensional (3D) scaffolds (PCL, PLLA and PCL-PLLA). Scaffold topographies were studied by scanning electron microscopy and it was found that the scaffolds had interconnected macroporous structures. HTGSCs were isolated from impacted third molar tooth germs of young adult patients and grown for 3 weeks on the scaffolds in chondrogenic differentiation medium. Cell proliferation on the scaffolds was determined by MTS assay and it was observed that all scaffolds supported cell proliferation. Immunostaining was carried out for morphological and differentiation analyses. Immunohistochemical analyses revealed that the cells attached onto the scaffolds and deposited cartilage-specific extracellular matrix (ECM). Real-time PCR was performed to determine the expression levels of cartilage-specific genes. After 21 days of incubation in cartilage differentiation medium, expression of collagen type II increased only in the cells seeded onto PCL-PLLA blend scaffolds. Similarly, aggrecan expression was the highest on PCL-PLLA scaffolds after 3weeks. These results suggest that all the scaffolds, and especially PCL-PLLA, were suitable for chondrogenic differentiation of HTGSCs. Copyright (C) 2015 John Wiley & Sons, Ltd.

The aim of this research was to investigate the osteogenic differentiation potential of non-invasively obtained human stem cells on collagen nanocomposite scaffolds with in situ-grown calcium phosphate crystals. The foams had 70\% porosity and pore sizes varying in the range 50-200 mu m. The elastic modulus and compressive strength of the calcium phosphate containing collagen scaffolds were determined to be 234.5 kPa and 127.1 kPa, respectively, prior to in vitro studies. Mesenchymal stem cells (MSCs) obtained from Wharton's jelly and menstrual blood were seeded on the collagen scaffolds and proliferation and osteogenic differentiation capacities of these cells from two different sources were compared. The cells on the composite scaffold showed the highest alkaline phosphatase activity compared to the controls, cells on tissue culture polystyrene and cells on collagen scaffolds without in situ-formed calcium phosphate. MSCs isolated from both Wharton's jelly and menstrual blood showed a significant level of osteogenic activity, but those from Wharton's jelly performed better. In this study it was shown that collagen nanocomposite scaffolds seeded with cells obtained non-invasively from human tissues could represent a potential construct to be used in bone tissue engineering. Copyright (C) 2012 John Wiley \& Sons, Ltd.

The present study aimed to investigate the effect of structure (design and porosity) on the matrix stiffness and osteogenic activity of stem cells cultured on poly(ester-urethane) (PEU) scaffolds. Different three-dimensional (3D) forms of scaffold were prepared from lysine-based PEU using traditional salt-leaching and advanced bioplotting techniques. The resulting scaffolds were characterized by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), mercury porosimetry and mechanical testing. The scaffolds had various pore sizes with different designs, and all were thermally stable up to 300â °C. In vitrotests, carried out using rat bone marrow stem cells (BMSCs) for bone tissue engineering, demonstrated better viability and higher cell proliferation on bioplotted scaffolds compared to salt-leached ones, most probably due to their larger and interconnected pores and stiffer nature, as shown by higher compressive moduli, which were measured by compression testing. Similarly, SEM, von Kossa staining and EDX analyses indicated higher amounts of calcium deposition on bioplotted scaffolds during cell culture. It was concluded that the design with larger interconnected porosity and stiffness has an effect on the osteogenic activity of the stem cells., This work was supported by the European FP6 NoE EXPERTISSUES project (Grant No. NMP3-500283), the mini-project Fibrocell, TUBITAK (Grant No. TBAG 105 T508 Nanobiomat) and by METU-BAP.

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PubMedID: 22162495 Tissue engineering and regenerative medicine aim to produce tissue substitutes to restore lost functions of tissues and organs. This includes cell therapies, induction of tissue/organ regeneration by biologically active molecules, or transplantation of in vitro grown tissues. This review article discusses advanced cell therapies that make use of scaffolds and scaffold-free approaches. The first part of this article covers the basic characteristics of scaffolds, including characteristics of scaffold material, fabrication and surface functionalization, and their applications in the construction of hard (bone and cartilage) and soft (nerve, skin, blood vessel, heart muscle) tissue substitutes. In addition, cell sources as well as bioreactive agents, such as growth factors, that guide cell functions are presented. The second part in turn, examines scaffold-free applications, with a focus on the recently discovered cell sheet engineering. This article serves as a good reference for all applications of advanced cell therapies and as well as advantages and limitations of scaffold-based and scaffold-free strategies. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A nerve conduit is designed to improve peripheral nerve regeneration by providing guidance to the nerve cells. Conductivity of such guides is reported to enhance this process. In the current study, a nerve guide was constructed from poly(2-hydroxyethyl methacrylate) (pHEMA), which was loaded with multiwalled carbon nanotubes (mwCNT) to introduce conductivity. PHEMA hydrogels were designed to have a porous structure to facilitate the transportation of the compounds needed for cell nutrition and growth and also for waste removal. We showed that when loaded with relatively high concentrations of mwCNTs (6%, w/w in hydrogels), the pHEMA guide was more conductive and more hydrophobic than pristine pHEMA hydrogel. The mechanical properties of the composites were better when they carried mwCNT. Elastic modulus of 6% mwCNT loaded pHEMA was twofold higher (0.32 +/- 0.06 MPa) and similar to that of the soft tissues. Electrical conductivity was significantly improved (11.4-fold) from 7 x 10(-3) (-1).cm(-1) (pHEMA) to 8.0 x 10(-2) (-1).cm(-1) (6% mwCNT loaded pHEMA). On application of electrical potential, the SHSY5Y neuroblastoma cells seeded on mwCNTs carrying pHEMA maintained their viability, whereas those on pure pHEMA could not, indicating that mwCNT helped conduct electricity and make them more suitable as nerve conduits. (c) 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 828-841, 2014.

… Tissue Engn & Regenerat Med Int Soc, European Chap

[No abstract available] Unlimited DSM;Integra;Cam Implants;Elsevier - Biomaterials;Instron 8th World Biomaterials Congress 2008, WBC 2008 -- 28 May 2008 through 1 June 2008 -- Amsterdam -- 93751

[Excerpt] The aim of this study was to develop a bone tissue engineering scaffold with an inherent bone morphogenetic proteins BMP-2 and BMP-7 sequential delivery system. BMPs were encapsulated in poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and poly(lactic acid-co-glycolic acid) (PLGA) nano/microparticules which are then introduced to a chitosan matrix by two methods: embedding in the chitosan fibers and then forming the scaffold or by forming the chitosan scaffold and then introducing the nano/microparticules. [...], info:eu-repo/semantics/publishedVersion