Ornamenting 3D printed scaffolds with cell-laid extracellular matrix for bone tissue regeneration.

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Pati, Falguni; Song, Tae-Ha; Rijal, Girdhari; Jang, Jinah; Kim, Sung Won; Cho, Dong-Woo

2015-01-01

3D printing technique is the most sophisticated technique to produce scaffolds with tailorable physical properties. But, these scaffolds often suffer from limited biological functionality as they are typically made from synthetic materials. Cell-laid mineralized ECM was shown to be potential for improving the cellular responses and drive osteogenesis of stem cells. Here, we intend to improve the biological functionality of 3D-printed synthetic scaffolds by ornamenting them with cell-laid mineralized extracellular matrix (ECM) that mimics a bony microenvironment. We developed bone graft substitutes by using 3D printed scaffolds made from a composite of polycaprolactone (PCL), poly(lactic-co-glycolic acid) (PLGA), and β-tricalcium phosphate (β-TCP) and mineralized ECM laid by human nasal inferior turbinate tissue-derived mesenchymal stromal cells (hTMSCs). A rotary flask bioreactor was used to culture hTMSCs on the scaffolds to foster formation of mineralized ECM. A freeze/thaw cycle in hypotonic buffer was used to efficiently decellularize (97% DNA reduction) the ECM-ornamented scaffolds while preserving its main organic and inorganic components. The ECM-ornamented 3D printed scaffolds supported osteoblastic differentiation of newly-seeded hTMSCs by upregulating four typical osteoblastic genes (4-fold higher RUNX2; 3-fold higher ALP; 4-fold higher osteocalcin; and 4-fold higher osteopontin) and increasing calcium deposition compared to bare 3D printed scaffolds. In vivo, in ectopic and orthotopic models in rats, ECM-ornamented scaffolds induced greater bone formation than that of bare scaffolds. These results suggest a valuable method to produce ECM-ornamented 3D printed scaffolds as off-the-shelf bone graft substitutes that combine tunable physical properties with physiological presentation of biological signals. Copyright © 2014 Elsevier Ltd. All rights reserved.

Analysis of 3D Printed Diopside Scaffolds Properties for Tissue Engineering

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Tingting LIU

2015-11-01

Full Text Available Diopside exhibits favorable potential for bone repair on account of the good mechanical performance, bioactivity and biocompatibility. In this paper, diopside scaffolds with high pore interconnectivity were successfully fabricated by laser three-dimensional (3D printing. The microstructure and mechanical performance of the diopside scaffolds were studied. The experimental analysis indicated that diopside particles gradually fused together until a dense structure was built with an energy density increasing in the range between 2.4 and 4.8 J·mm-2. Meanwhile, compressive strength and fracture toughness increased gradually from 5.96 ± 0.88 MPa to 10.87 ± 0.55 MPa. However, mechanical properties decreased due to the appearance of voids when energy density were 5.4 and 6 J·mm-2. Simulated body fluid (SBF tests showed that apatite crystals formed on the diopside scaffolds surface, and the apatite crystals increased with soaking time. Cell culture tests indicated the scaffolds supported the adhesion and growth of MG-63 cells. The study suggested that diopside scaffolds fabricated by laser 3D printing are promising candidates for bone tissue engineering.DOI: http://dx.doi.org/10.5755/j01.ms.21.4.9845

3D printing process of oxidized nanocellulose and gelatin scaffold.

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Xu, Xiaodong; Zhou, Jiping; Jiang, Yani; Zhang, Qi; Shi, Hongcan; Liu, Dongfang

2018-08-01

For tissue engineering applications tissue scaffolds need to have a porous structure to meet the needs of cell proliferation/differentiation, vascularisation and sufficient mechanical strength for the specific tissue. Here we report the results of a study of the 3D printing process for composite materials based on oxidized nanocellulose and gelatin, that was optimised through measuring rheological properties of different batches of materials after different crosslinking times, simulation of the pneumatic extrusion process and 3D scaffolds fabrication with Solidworks Flow Simulation, observation of its porous structure by SEM, measurement of pressure-pull performance, and experiments aimed at finding out the vitro cytotoxicity and cell morphology. The materials printed are highly porous scaffolds with good mechanical properties.

Directed Self-Inquiry: A Scaffold for Teaching Laboratory Report Writing

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Deiner, L. Jay; Newsome, Daniel; Samaroo, Diana

2012-01-01

A scaffold was created for the explicit instruction of laboratory report writing. The scaffold breaks the laboratory report into sections and teaches students to ask and answer questions in order to generate section-appropriate content and language. Implementation of the scaffold is done through a series of section-specific worksheets that are…

Fabrication and characterization of SrAl{sub 2}O{sub 4}: Eu{sup 2+} Dy{sup 3+}/CS-PCL electrospun nanocomposite scaffold for retinal tissue regeneration

Energy Technology Data Exchange (ETDEWEB)

Sepahvandi, Azadeh; Eskandari, Mahnaz, E-mail: eskandarim@aut.ac.ir; Moztarzadeh, Fathollah

2016-09-01

Millions of people around the world become blind due to losing a part of the retina cells. In tissue engineering field one way to address this issue is to develop a retina tissue by scaffolds based on structure and signals received These scaffolds can play an essential role in repair and reformation of the damaged retina tissue. Here, SrAl{sub 2}O{sub 4}: Eu{sup 2+}, Dy{sup 3+} nanophosphor were prepared by sol-gel method and then coated with PEG to become biocompatible. Next 10%, 30% and 50% concentration of the coated nanophosphors were dispersed in CS-PCL copolymer and electrospuned to form SrAl{sub 2}O{sub 4}: Eu{sup 2+}, Dy{sup 3+}/CS-PCL scaffolds. The aforementioned photo –luminescence-scaffolds were studied for their optical, mechanical and morphological characteristics finally the effect of these scaffolds on the mice RPCs cells' proliferation and differentiation was observed. The 30% nanophosphor dispersion scaffold while providing adequate mechanical flexibility and integrity, and exhibiting superior proliferation rates and acceptable differentiation into retinal neural cells (particularly photo receptors retinal) is suggested as a promising choice in retinal tissue repair. - Highlights: • The 30% nanophosphor dispersion scaffold for both shorter wavelength and middle intense emission is more near to biocompatible nanophosphors. • 30% dispersed nanophosphor scaffold displays satisfactory mechanical strength and flexibility where its behavior is similar to the retina tissue. • Besides as the most effective signal in this study is the electromagnetic signals emitted by nanophosphors, we attribute the enhanced proliferation to the positive effects of the later, the emitted signals of scaffolds. • The tendency towards spherical morphology implies that emitting light may stimulate the cell signaling toward differentiation • These findings implies that mRPC grown on SrAl{sub 2}O{sub 4}: Eu{sup 2+},Dy{sup 3+}/CS-PCL scaffolds in differentiation

Efficacy Study of Carrageenan as an Alternative Infused Material (Filler in Poly(3-hydroxybutyrate-co-3-hydroxyvalerate Porous 3D Scaffold

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Nor Syamimi Che Johari

2017-01-01

Full Text Available Polymeric porous 3D scaffold plays an important role in culturing mammalian cells as ex vivo model. However, the scaffold used is ineffective due to its structural and cell acceptability weaknesses. Therefore, this research attempts to overcome the weaknesses by using carrageenan from red seaweed Kappaphycus alvarezii as an alternative infused material (filler of poly(3-hydroxybutyrate-co-3-hydroxyvalerate (PHBV porous 3D scaffold. The 3D scaffold was conventionally fabricated using the solvent-casting particulate-leaching (SCPL method. Carrageenan was later infused into 3D porous scaffolds under vacuum pressure and freeze-drying process. Five carrageenan concentrations were prepared and its physicochemical properties such as pH and viscosity were carried out on each concentration to determine the best solutions to produce a new composite 3D structure. The preliminary result shows that carrageenan concentrations of 2, 4, and 6% (w/v were considered the best solutions for the infusion process due to its stable rheology properties. The pH and viscosity profiles of three selected carrageenan solutions were exhibited in the range of 9.00–9.20 and 0.047–1.144 Pa·s, respectively. Moreover, the incorporated carrageenan gel fraction was in the range of 4.30% to 14.95% (w/w which was determined by gravimetric analysis and dye staining method (visual assessment. The well-infused carrageenan 3D scaffold was further characterized based on its internal morphology and degradability study. The vertical cross-sections of the scaffolds revealed homogeneous accumulation of dried gelatinous carrageenan which was covered throughout its pores wall. The degradation rate (K of the carrageenan infused 3D scaffold was between 0.01±1.66 (mg/day and 0.03±3.23 (mg/day. The higher the carrageenan concentration used, the faster the degradation rate occurring (p2 weeks. In conclusion, the usage of carrageenan as a composite material exhibits its great potential to be

Design and synthesis of novel platelet fibrinogen receptor antagonists with 2H-1,4-benzoxazine-3(4H)-one scaffold. A systematic study.

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Anderluh, Marko; Cesar, Jozko; Stefanic, Petra; Kikelj, Danijel; Janes, Damjan; Murn, Jernej; Nadrah, Kristina; Tominc, Mojca; Addicks, Elisabeth; Giannis, Athanassios; Stegnar, Mojca; Dolenc, Marija Sollner

2005-01-01

New platelet glycoprotein IIb/IIIa (GP IIb/IIIa, integrin alpha(IIb)beta3) antagonists were prepared on a 2H-1,4-benzoxazine-3(4H)-one scaffold. Their anti-aggregatory activities in human platelet rich plasma and their affinity towards alpha(IIb)beta3 and alpha(V)beta3 integrins were assessed. Various substitution positions and side chain variations were studied. In contrast to the generally accepted model, compounds containing ethyl esters as aspartate mimetics were in general more active than the corresponding free acids. We suggest an explanation for the observed behaviour of these new compounds.

Design and production of sintered β-tricalcium phosphate 3D scaffolds for bone tissue regeneration

International Nuclear Information System (INIS)

Santos, Carlos F.L.; Silva, Abílio P.; Lopes, Luís; Pires, Inês; Correia, Ilidio J.

2012-01-01

The characteristics of sintered β-tricalcium phosphate (β-TCP) scaffolds produced by 3D printing were studied by means of X-ray diffraction, Scanning Electron Microscopy, Fourier transform infrared spectroscopy, uniaxial compression tests and cytotoxicity tests, using human osteoblast cells. The results reported include details of the β-TCP scaffolds' porosity, density, phase stability, mechanical behavior and cytotoxic profile. Collectively, these properties are fundamental for the future application of these scaffolds as bone substitutes for individualized therapy. Highlights: ► β-Tricalcium phosphate (β-TCP) 3D scaffolds were produced by rapid prototyping. ► Scaffold properties were assessed by SEM, FTIR, XRD and by mechanical tests. ► The cytotoxic profile of the scaffolds was characterized by in vitro assays. ► Scaffolds have good properties for its application as bone substitutes for individualized therapy.

The design of 3D scaffold for tissue engineering using automated scaffold design algorithm.

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Mahmoud, Shahenda; Eldeib, Ayman; Samy, Sherif

2015-06-01

Several progresses have been introduced in the field of bone regenerative medicine. A new term tissue engineering (TE) was created. In TE, a highly porous artificial extracellular matrix or scaffold is required to accommodate cells and guide their growth in three dimensions. The design of scaffolds with desirable internal and external structure represents a challenge for TE. In this paper, we introduce a new method known as automated scaffold design (ASD) for designing a 3D scaffold with a minimum mismatches for its geometrical parameters. The method makes use of k-means clustering algorithm to separate the different tissues and hence decodes the defected bone portions. The segmented portions of different slices are registered to construct the 3D volume for the data. It also uses an isosurface rendering technique for 3D visualization of the scaffold and bones. It provides the ability to visualize the transplanted as well as the normal bone portions. The proposed system proves good performance in both the segmentation results and visualizations aspects.

Antimicrobial activities of pyridinium-tailored pyrazoles bearing 1,3,4-oxadiazole scaffolds

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Lei Zhou

2017-11-01

Full Text Available Herein, a series of pyridinium-tailored 5-trifluoromethylpyrazoles containing 1,3,4-oxadiazole moieties were constructed through coupling key pharmaceutical fragments of pyridinium, pyrazole, and 1,3,4-oxadiazole scaffolds in single molecular architecture. Antimicrobial results suggested that this kind of compounds exhibited significant activities against three types of pathogenic bacteria and six fungal strains in vitro. The minimal EC50 values of designed compounds against Xanthomonas oryzae pv. oryzae, Ralstonia solanacearum, and Xanthomonas axonopodis pv. citri could reach to 0.467, 1.04, and 0.600 μg/mL, respectively, through tuning and optimizing N-substituents, bridging atom, and alkyl length of the tailor. Antifungal assays revealed that all title molecules possessed considerable activity against Botrytis cinerea with the minimal EC50 value up to 2.71 μg/mL; and compounds I-8, I-10, I-12, II-12, and IV-12 showed the strongest growth suppression toward Rhizoctonia solani with EC50 values ranging from 10.2 to 24.0 μg/mL. Given the above results, this kind of compounds could serve as new lead compounds in the research of antimicrobial chemotherapy.

Improving osteointegration and osteogenesis of three-dimensional porous Ti6Al4V scaffolds by polydopamine-assisted biomimetic hydroxyapatite coating.

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Li, Yong; Yang, Wei; Li, Xiaokang; Zhang, Xing; Wang, Cairu; Meng, Xiangfei; Pei, Yifeng; Fan, Xiangli; Lan, Pingheng; Wang, Chunhui; Li, Xiaojie; Guo, Zheng

2015-03-18

Titanium alloys with various porous structures can be fabricated by advanced additive manufacturing techniques, which are attractive for use as scaffolds for bone defect repair. However, modification of the scaffold surfaces, particularly inner surfaces, is critical to improve the osteointegration of these scaffolds. In this study, a biomimetic approach was employed to construct polydopamine-assisted hydroxyapatite coating (HA/pDA) onto porous Ti6Al4V scaffolds fabricated by the electron beam melting method. The surface modification was characterized with the field emission scanning electron microscopy, energy dispersive spectroscopy, water contact angle measurement, and confocal laser scanning microscopy. Attachment and proliferation of MC3T3-E1 cells on the scaffold surface were significantly enhanced by the HA/pDA coating compared to the unmodified surfaces. Additionally, MC3T3-E1 cells grown on the HA/pDA-coated Ti6Al4V scaffolds displayed significantly higher expression of runt-related transcription factor-2, alkaline phosphatase, osteocalcin, osteopontin, and collagen type-1 compared with bare Ti6Al4V scaffolds after culture for 14 days. Moreover, microcomputed tomography analysis and Van-Gieson staining of histological sections showed that HA/pDA coating on surfaces of porous Ti6Al4V scaffolds enhanced osteointegration and significantly promoted bone regeneration after implantation in rabbit femoral condylar defects for 4 and 12 weeks. Therefore, this study provides an alternative to biofunctionalized porous Ti6Al4V scaffolds with improved osteointegration and osteogenesis functions for orthopedic applications.

Apple derived cellulose scaffolds for 3D mammalian cell culture.

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Daniel J Modulevsky

Full Text Available There are numerous approaches for producing natural and synthetic 3D scaffolds that support the proliferation of mammalian cells. 3D scaffolds better represent the natural cellular microenvironment and have many potential applications in vitro and in vivo. Here, we demonstrate that 3D cellulose scaffolds produced by decellularizing apple hypanthium tissue can be employed for in vitro 3D culture of NIH3T3 fibroblasts, mouse C2C12 muscle myoblasts and human HeLa epithelial cells. We show that these cells can adhere, invade and proliferate in the cellulose scaffolds. In addition, biochemical functionalization or chemical cross-linking can be employed to control the surface biochemistry and/or mechanical properties of the scaffold. The cells retain high viability even after 12 continuous weeks of culture and can achieve cell densities comparable with other natural and synthetic scaffold materials. Apple derived cellulose scaffolds are easily produced, inexpensive and originate from a renewable source. Taken together, these results demonstrate that naturally derived cellulose scaffolds offer a complementary approach to existing techniques for the in vitro culture of mammalian cells in a 3D environment.

Application of Synthetic Polymeric Scaffolds in Breast Cancer 3D Tissue Cultures and Animal Tumor Models

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Girdhari Rijal

2017-01-01

Full Text Available Preparation of three-dimensional (3D porous scaffolds from synthetic polymers is a challenge to most laboratories conducting biomedical research. Here, we present a handy and cost-effective method to fabricate polymeric hydrogel and porous scaffolds using poly(lactic-co-glycolic acid (PLGA or polycaprolactone (PCL. Breast cancer cells grown on 3D polymeric scaffolds exhibited distinct survival, morphology, and proliferation compared to those on 2D polymeric surfaces. Mammary epithelial cells cultured on PLGA- or PCL-coated slides expressed extracellular matrix (ECM proteins and their receptors. Estrogen receptor- (ER- positive T47D breast cancer cells are less sensitive to 4-hydroxytamoxifen (4-HT treatment when cultured on the 3D porous scaffolds than in 2D cultures. Finally, cancer cell-laden polymeric scaffolds support consistent tumor formation in animals and biomarker expression as seen in human native tumors. Our data suggest that the porous synthetic polymer scaffolds satisfy the basic requirements for 3D tissue cultures both in vitro and in vivo. The scaffolding technology has appealing potentials to be applied in anticancer drug screening for a better control of the progression of human cancers.

Design and production of sintered {beta}-tricalcium phosphate 3D scaffolds for bone tissue regeneration

Energy Technology Data Exchange (ETDEWEB)

Santos, Carlos F.L. [CICS-UBI - Centro de Investigacao em Ciencias da Saude, Universidade da Beira Interior, Covilha (Portugal); Silva, Abilio P. [Centro de Ciencia e Tecnologia Aeroespaciais, Universidade da Beira Interior, Covilha (Portugal); Lopes, Luis [CICS-UBI - Centro de Investigacao em Ciencias da Saude, Universidade da Beira Interior, Covilha (Portugal); Pires, Ines [Instituto de Engenharia Mecanica - Lisboa (IDMEC Lisboa/IST/UTL), Avenida Rovisco Pais, 1049-001 Lisboa (Portugal); Correia, Ilidio J., E-mail: icorreia@ubi.pt [CICS-UBI - Centro de Investigacao em Ciencias da Saude, Universidade da Beira Interior, Covilha (Portugal)

2012-07-01

The characteristics of sintered {beta}-tricalcium phosphate ({beta}-TCP) scaffolds produced by 3D printing were studied by means of X-ray diffraction, Scanning Electron Microscopy, Fourier transform infrared spectroscopy, uniaxial compression tests and cytotoxicity tests, using human osteoblast cells. The results reported include details of the {beta}-TCP scaffolds' porosity, density, phase stability, mechanical behavior and cytotoxic profile. Collectively, these properties are fundamental for the future application of these scaffolds as bone substitutes for individualized therapy. Highlights: Black-Right-Pointing-Pointer {beta}-Tricalcium phosphate ({beta}-TCP) 3D scaffolds were produced by rapid prototyping. Black-Right-Pointing-Pointer Scaffold properties were assessed by SEM, FTIR, XRD and by mechanical tests. Black-Right-Pointing-Pointer The cytotoxic profile of the scaffolds was characterized by in vitro assays. Black-Right-Pointing-Pointer Scaffolds have good properties for its application as bone substitutes for individualized therapy.

Multifunctional pH sensitive 3D scaffolds for treatment and prevention of bone infection.

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Cicuéndez, Mónica; Doadrio, Juan C; Hernández, Ana; Portolés, M Teresa; Izquierdo-Barba, Isabel; Vallet-Regí, María

2018-01-01

Multifunctional-therapeutic three-dimensional (3D) scaffolds have been prepared. These biomaterials are able to destroy the S. aureus bacterial biofilm and to allow bone regeneration at the same time. The present study is focused on the design of pH sensitive 3D hierarchical meso-macroporous 3D scaffolds based on MGHA nanocomposite formed by a mesostructured glassy network with embedded hydroxyapatite nanoparticles, whose mesopores have been loaded with levofloxacin (Levo) as antibacterial agent. These 3D platforms exhibit controlled and pH-dependent Levo release, sustained over time at physiological pH (7.4) and notably increased at infection pH (6.7 and 5.5), which is due to the different interaction rate between diverse Levo species and the silica matrix. These 3D systems are able to inhibit the S. aureus growth and to destroy the bacterial biofilm without cytotoxic effects on human osteoblasts and allowing an adequate colonization and differentiation of preosteoblastic cells on their surface. These findings suggest promising applications of these hierarchical MGHA nanocomposite 3D scaffolds for the treatment and prevention of bone infection. Multifunctional 3D nanocomposite scaffolds with the ability for loading and sustained delivery of an antimicrobial agent, to eliminate and prevent bone infection and at the same time to contribute to bone regeneration process without cytotoxic effects on the surrounding tissue has been proposed. These 3D scaffolds exhibit a sustained levofloxacin delivery at physiological pH (pH 7.4), which increasing notably when pH decreases to characteristic values of bone infection process (pH 6.7 and pH 5.5). In vitro competitive assays between preosteoblastic and bacteria onto the 3D scaffold surface demonstrated an adequate osteoblast colonization in entire scaffold surface together with the ability to eliminate bacteria contamination. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

3D Printing of Scaffolds for Tissue Regeneration Applications

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Do, Anh-Vu; Khorsand, Behnoush; Geary, Sean M.; Salem, Aliasger K.

2015-01-01

The current need for organ and tissue replacement, repair and regeneration for patients is continually growing such that supply is not meeting the high demand primarily due to a paucity of donors as well as biocompatibility issues that lead to immune rejection of the transplant. In an effort to overcome these drawbacks, scientists working in the field of tissue engineering and regenerative medicine have investigated the use of scaffolds as an alternative to transplantation. These scaffolds are designed to mimic the extracellular matrix (ECM) by providing structural support as well as promoting attachment, proliferation, and differentiation with the ultimate goal of yielding functional tissues or organs. Initial attempts at developing scaffolds were problematic and subsequently inspired a growing interest in 3D printing as a mode for generating scaffolds. Utilizing three-dimensional printing (3DP) technologies, ECM-like scaffolds can be produced with a high degree of complexity and precision, where fine details can be included at a micron level. In this review, we discuss the criteria for printing viable and functional scaffolds, scaffolding materials, and 3DP technologies used to print scaffolds for tissue engineering. A hybrid approach, employing both natural and synthetic materials, as well as multiple printing processes may be the key to yielding an ECM-like scaffold with high mechanical strength, porosity, interconnectivity, biocompatibility, biodegradability, and high processability. Creating such biofunctional scaffolds could potentially help to meet the demand by patients for tissues and organs without having to wait or rely on donors for transplantation. PMID:26097108

Quantitative determination of residual 1,4-dioxane in three-dimensional printed bone scaffold

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Ling Li

2018-04-01

Full Text Available Summary: Background/Objective: A novel porous scaffold poly (lactide-co-glycolide and tricalcium phosphate (PLGA/TCP was developed by three-dimensional printing technology for bone defect repair. As a Class 2 solvent with less severe toxicity, content of residual 1,4-dioxane in this newly developed scaffold should be rigorously controlled when it is translated to clinical use. In this study, a headspace gas chromatography-mass spectrometric (HS-GC-MS method and related testing protocol were developed for quantitative determination of 1,4-dioxane in the PLGA/TCP composite scaffolds. Methods: Matrix effect analysis was used to optimise the pretreatment method of the scaffolds. Then, the procedure for testing 1,4-dioxane using HS-GC-MS was set up. The accuracy, precision, and robustness of this newly developed quantitative method were also validated before quantification of 1,4-dioxane in the scaffolds with different drying procedures. Results: Dimethyl formamide (DMF was the optimal solvent for dissolving scaffolds for GC-MS with proper sensitivity and without matrix effect. Then, the optimised procedure was determined as: the scaffolds were dissolved in DMF and kept at 90°C for 40 minutes, separated on a HP-5MS column, and detected by mass spectroscopy. Recovery experiments gave 97.9–100.7% recovery for 1,4-dioxane. The linear range for 1,4-dioxane was determined as 1–40 ppm with linear correlation coefficient ≥ 0.9999. Intraday and interday precision was determined as being within relative standard deviation of below 0.68%. The passable drying procedure was related to lyophilising (−50°C, 50 Pa the scaffolds for 2 days and drying in vacuum (50 Pa for 7 days. Conclusion: This is the first quantitative method established to test 1,4-dixoane in a novel scaffold. This method was validated with good accuracy and reproducibility, and met the methodological requirements of the Guideline 9101 documented in the Chinese Pharmacopoeia 2015

Spiral-structured, nanofibrous, 3D scaffolds for bone tissue engineering.

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Wang, Junping; Valmikinathan, Chandra M; Liu, Wei; Laurencin, Cato T; Yu, Xiaojun

2010-05-01

Polymeric nanofiber matrices have already been widely used in tissue engineering. However, the fabrication of nanofibers into complex three-dimensional (3D) structures is restricted due to current manufacturing techniques. To overcome this limitation, we have incorporated nanofibers onto spiral-structured 3D scaffolds made of poly (epsilon-caprolactone) (PCL). The spiral structure with open geometries, large surface areas, and porosity will be helpful for improving nutrient transport and cell penetration into the scaffolds, which are otherwise limited in conventional tissue-engineered scaffolds for large bone defects repair. To investigate the effect of structure and fiber coating on the performance of the scaffolds, three groups of scaffolds including cylindrical PCL scaffolds, spiral PCL scaffolds (without fiber coating), and spiral-structured fibrous PCL scaffolds (with fiber coating) have been prepared. The morphology, porosity, and mechanical properties of the scaffolds have been characterized. Furthermore, human osteoblast cells are seeded on these scaffolds, and the cell attachment, proliferation, differentiation, and mineralized matrix deposition on the scaffolds are evaluated. The results indicated that the spiral scaffolds possess porosities within the range of human trabecular bone and an appropriate pore structure for cell growth, and significantly lower compressive modulus and strength than cylindrical scaffolds. When compared with the cylindrical scaffolds, the spiral-structured scaffolds demonstrated enhanced cell proliferation, differentiation, and mineralization and allowed better cellular growth and penetration. The incorporation of nanofibers onto spiral scaffolds further enhanced cell attachment, proliferation, and differentiation. These studies suggest that spiral-structured nanofibrous scaffolds may serve as promising alternatives for bone tissue engineering applications. Copyright 2009 Wiley Periodicals, Inc.

Production of Composite Scaffold Containing Silk Fibroin, Chitosan, and Gelatin for 3D Cell Culture and Bone Tissue Regeneration.

Science.gov (United States)

Li, Jianqing; Wang, Qiuke; Gu, Yebo; Zhu, Yu; Chen, Liang; Chen, Yunfeng

2017-11-08

BACKGROUND Bone tissue engineering, a powerful tool to treat bone defects, is highly dependent on use of scaffolds. Both silk fibroin (SF) and chitosan (Cs) are biocompatible and actively studied for reconstruction of tissue engineering. Gelatin (Gel) is also widely applied in the biomedical field due to its low antigenicity and physicochemical stability. MATERIAL AND METHODS In this study, 4 different types of scaffolds were constructed - SF, SF/Cs, SF/Gel, and SF/Cs/Gel - and we compared their physical and chemical properties as well as biological characterization of these scaffolds to determine the most suitable scaffold for use in bone regeneration. First, these scaffolds were produced via chemical cross-linking method and freeze-drying technique. Next, the characterization of internal structure was studied using scanning electron microscopy and the porosity was evaluated by liquid displacement method. Then, we compared physicochemical properties such as water absorption rate and degradation property. Finally, MC3T3-E1 cells were inoculated on the scaffolds to study the biocompatibility and osteogenesis of the three-dimensional (3D) scaffolds in vitro. RESULTS The composite scaffold formed by all 3 components was the best for use in bone regeneration. CONCLUSIONS We conclude that the best scaffold among the 4 studied for MC3T3-E1 cells is our SF/Cs/Gel scaffold, suggesting a new choice for bone regeneration that can be used to treat bone defects or fractures in clinical practice.

DNA Origami Scaffolds as Templates for Functional Tetrameric Kir3 K+ Channels.

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Kurokawa, Tatsuki; Kiyonaka, Shigeki; Nakata, Eiji; Endo, Masayuki; Koyama, Shohei; Mori, Emiko; Tran, Nam Ha; Dinh, Huyen; Suzuki, Yuki; Hidaka, Kumi; Kawata, Masaaki; Sato, Chikara; Sugiyama, Hiroshi; Morii, Takashi; Mori, Yasuo

2018-03-01

In native systems, scaffolding proteins play important roles in assembling proteins into complexes to transduce signals. This concept is yet to be applied to the assembly of functional transmembrane protein complexes in artificial systems. To address this issue, DNA origami has the potential to serve as scaffolds that arrange proteins at specific positions in complexes. Herein, we report that Kir3 K + channel proteins are assembled through zinc-finger protein (ZFP)-adaptors at specific locations on DNA origami scaffolds. Specific binding of the ZFP-fused Kir3 channels and ZFP-based adaptors on DNA origami were confirmed by atomic force microscopy and gel electrophoresis. Furthermore, the DNA origami with ZFP binding sites nearly tripled the K + channel current activity elicited by heterotetrameric Kir3 channels in HEK293T cells. Thus, our method provides a useful template to control the oligomerization states of membrane protein complexes in vitro and in living cells. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

3D Printed Silicone–Hydrogel Scaffold with Enhanced Physicochemical Properties

DEFF Research Database (Denmark)

Mohanty, Soumyaranjan; Alm, Martin; Hemmingsen, Mette

2016-01-01

is currently a huge challenge. The goal of this work was to fabricate a tissue engineering scaffold from clinically approved materials with the capability of delivering biomolecules and direct cell fate. We have used a simple 3D printing approach, that combines polymer casting with supercritical fluid...... technology to produce 3D interpenetrating polymer network (IPN) scaffold of silicone-poly(2-hydroxyethyl methacrylate)-co-poly(ethylene glycol) methyl ether acrylate (pHEMA-co-PEGMEA). The pHEMA-co-PEGMEA IPN materials were employed to support growth of human mesenchymal stem cells (hMSC), resulting in high...... cell viability and metabolic activity over a 3 weeks period. In addition, the IPN scaffolds support 3D tissue formation inside the porous scaffold with well spread cell morphology on the surface of the scaffold. As a proof of concept, sustained doxycycline (DOX) release from pHEMA-co-PEGMEA IPN...

Gas-Foamed Scaffold Gradients for Combinatorial Screening in 3D

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Joachim Kohn

2012-03-01

Full Text Available Current methods for screening cell-material interactions typically utilize a two-dimensional (2D culture format where cells are cultured on flat surfaces. However, there is a need for combinatorial and high-throughput screening methods to systematically screen cell-biomaterial interactions in three-dimensional (3D tissue scaffolds for tissue engineering. Previously, we developed a two-syringe pump approach for making 3D scaffold gradients for use in combinatorial screening of salt-leached scaffolds. Herein, we demonstrate that the two-syringe pump approach can also be used to create scaffold gradients using a gas-foaming approach. Macroporous foams prepared by a gas-foaming technique are commonly used for fabrication of tissue engineering scaffolds due to their high interconnectivity and good mechanical properties. Gas-foamed scaffold gradient libraries were fabricated from two biodegradable tyrosine-derived polycarbonates: poly(desaminotyrosyl-tyrosine ethyl ester carbonate (pDTEc and poly(desaminotyrosyl-tyrosine octyl ester carbonate (pDTOc. The composition of the libraries was assessed with Fourier transform infrared spectroscopy (FTIR and showed that pDTEc/pDTOc gas-foamed scaffold gradients could be repeatably fabricated. Scanning electron microscopy showed that scaffold morphology was similar between the pDTEc-rich ends and the pDTOc-rich ends of the gradient. These results introduce a method for fabricating gas-foamed polymer scaffold gradients that can be used for combinatorial screening of cell-material interactions in 3D.

Effects of chitosan and bioactive glass modifications of knitted and rolled polylactide-based 96/4 L/D scaffolds on chondrogenic differentiation of adipose stem cells.

Science.gov (United States)

Ahtiainen, Katja; Sippola, Laura; Nurminen, Manu; Mannerström, Bettina; Haimi, Suvi; Suuronen, Riitta; Hyttinen, Jari; Ylikomi, Timo; Kellomäki, Minna; Miettinen, Susanna

2015-01-01

The performance of biodegradable knitted and rolled 3-dimensional (3D) polylactide-based 96/4 scaffolds modified with bioactive glass (BaG) 13-93, chitosan and both was compared with regard to the viability, proliferation and chondrogenic differentiation of rabbit adipose stem cells (ASCs). Scaffold porosities were determined by micro-computed tomography (μCT). Water absorption and degradation of scaffolds were studied during 28-day hydrolysis in Tris-buffer. Viability, number and differentiation of ASCs in PLA96/4 scaffolds were examined in vitro. The dimensions of the scaffolds were maintained during hydrolysis and mass loss was detected only in the BaG13-93 containing scaffolds. ASCs adhered and proliferated on each scaffold type. Cell aggregation and expression of chondral matrix components improved in all scaffold types in chondrogenic medium. Signs of hypertrophy were detected in the modified scaffolds but not in the plain PLA96/4 scaffold. Chondrogenic differentiation was most enhanced in the presence of chitosan. These findings indicate that the plain P scaffold provided a good 3D-matrix for ASC proliferation whereas the addition of chitosan to the PLA96/4 scaffold induced chondrogenic differentiation independent of the medium. Accordingly, a PLA96/4 scaffold modified by chitosan could provide a functional and bioactive basis for tissue-engineered chondral implants. Copyright © 2012 John Wiley & Sons, Ltd.

Development of porous Ti6Al4V/chitosan sponge composite scaffold for orthopedic applications

International Nuclear Information System (INIS)

Guo, Miao; Li, Xiang

2016-01-01

A novel composite scaffold consisting of porous Ti6Al4V part filled with chitosan sponge was fabricated using a combination of electron beam melting and freeze-drying. The mechanical properties of porous Ti6Al4V part were examined via compressive test. The ultimate compressive strength was 85.35 ± 8.68 MPa and the compressive modulus was 2.26 ± 0.42 GPa. The microstructure of composite scaffold was characterized using scanning electron microscopy. The chitosan sponge filled in Ti6Al4V part exhibited highly porous and well-interconnected micro-pore architecture. The osteoblastic cells were seeded on scaffolds to test their seeding efficiency and biocompatibility. Significantly higher cell seeding efficiency was found on composite scaffold. The biological response of osteoblasts on composite scaffolds was superior in terms of improved cell attachment, higher proliferation, and well-spread morphology in relation to porous Ti6Al4V part. These results suggest that the Ti6Al4V/chitosan composite scaffold is potentially useful as a biomedical scaffold for orthopedic applications. - Highlights: • A novel composite scaffold with sufficient mechanical properties and favorable cell affinity environment was developed. • Significantly higher cell seeding efficiency was found on composite scaffold. • The osteoblasts on composite scaffolds showed well-spread morphology, improved cell attachment and higher proliferation.

Biocomposite scaffolds for bone regeneration: Role of chitosan and hydroxyapatite within poly-3-hydroxybutyrate-co-3-hydroxyvalerate on mechanical properties and in vitro evaluation.

Science.gov (United States)

Zhang, Sai; Prabhakaran, Molamma P; Qin, Xiaohong; Ramakrishna, Seeram

2015-11-01

Bio-engineered scaffolds for bone tissue regeneration is an exploding area of research mainly because they can satisfy the essential demands and current challenges in bone replacement therapies, by imitating the extracellular matrix (ECM) of the native bone. We fabricated bio-composite nanofibrous scaffolds with a blend of poly-3-hydroxybutyrate-co-3-hydroxyvalerate (PHBV), chitosan (CTS) and hydroxyapatite (HA) during this study. Morphological evaluation confirmed the fiber diameters of PHBV, PHBV/CTS (90:10), PHBV/CTS/HA4 (85.5:9.5:5) and PHBV/CTS/HA8 (81:9:10) as 405 ± 74 nm, 334 ± 82 nm, 316 ± 103 nm and 256 ± 110 nm, respectively. The PHBV/CTS/HA4 and PHBV/CTS/HA8 scaffolds were capable of enduring the long term culture of human fetal osteoblasts (hFOB) with ultimate tensile strength of 3.55 ± 0.22 MPa and 4.19 ± 0.19 MPa, respectively. The proliferation of osteoblasts on PHBV/CTS/HA8 scaffold was found 34.10% higher than that on PHBV scaffold on day 20. Cell maturation identified by alkaline phosphatase activity on day 20 was significantly higher on PHBV/CTS/HA8 scaffold than that on PHBV scaffold. The cells on PHBV/CTS/HA8 scaffold also acquired higher mineral deposition (25.79%) than the mineral deposition on PHBV scaffold by day 20, confirmed by EDX analysis. Based on the results, we concluded that the electrospun PHBV/CTS/HA8 scaffolds hold great potential to promote the regeneration of bone tissue due to the synergistic effect of chitosan and HA, whereby chitosan provided cell recognition sites while HA acted as a chelating agent for organizing the apatite-like mineralization. Copyright © 2015 Elsevier Ltd. All rights reserved.

Additive manufactured Ti6Al4V scaffolds with the RF- magnetron sputter deposited hydroxyapatite coating

International Nuclear Information System (INIS)

Chudinova, E; Surmeneva, M; Surmenev, R; Koptioug, A; Scoglund, P

2016-01-01

Present paper reports on the results of surface modification of the additively manufactured porous Ti6Al4V scaffolds. Radio frequency (RF) magnetron sputtering was used to modify the surface of the alloy via deposition of the biocompatible hydroxyapatite (HA) coating. The surface morphology, chemical and phase composition of the HA-coated alloy were studied. It was revealed that RF magnetron sputtering allows preparing a homogeneous HA coating onto the entire surface of scaffolds. (paper)

A computational modeling approach for the characterization of mechanical properties of 3D alginate tissue scaffolds.

Science.gov (United States)

Nair, K; Yan, K C; Sun, W

2008-01-01

Scaffold guided tissue engineering is an innovative approach wherein cells are seeded onto biocompatible and biodegradable materials to form 3-dimensional (3D) constructs that, when implanted in the body facilitate the regeneration of tissue. Tissue scaffolds act as artificial extracellular matrix providing the environment conducive for tissue growth. Characterization of scaffold properties is necessary to understand better the underlying processes involved in controlling cell behavior and formation of functional tissue. We report a computational modeling approach to characterize mechanical properties of 3D gellike biomaterial, specifically, 3D alginate scaffold encapsulated with cells. Alginate inherent nonlinearity and variations arising from minute changes in its concentration and viscosity make experimental evaluation of its mechanical properties a challenging and time consuming task. We developed an in silico model to determine the stress-strain relationship of alginate based scaffolds from experimental data. In particular, we compared the Ogden hyperelastic model to other hyperelastic material models and determined that this model was the most suitable to characterize the nonlinear behavior of alginate. We further propose a mathematical model that represents the alginate material constants in Ogden model as a function of concentrations and viscosity. This study demonstrates the model capability to predict mechanical properties of 3D alginate scaffolds.

Fabrication Of Scaffolds From Ti6Al4V Powders Using The Computer Aided Laser Method

Directory of Open Access Journals (Sweden)

Dobrzański L.A.

2015-06-01

Full Text Available The aim of the research, the results of which are presented in the paper, is to fabricate, by Selective Laser Melting (SLM, a metallic scaffold with Ti6Al4V powder based on a virtual model corresponding to the actual loss of a patient’s craniofacial bone. A plaster cast was made for a patient with a palate recess, and the cast was then scanned with a 3D scanner to create a virtual 3D model of a palate recess, according to which a 3D model of a solid implant was created using specialist software. The virtual 3D solid implant model was converted into a 3D porous implant model after designing an individual shape of the unit cell conditioning the size and three-dimensional shape of the scaffold pores by multiplication of unit cells. The data concerning a virtual 3D porous implant model was transferred into a selective laser melting (SLM device and a metallic scaffold was produced from Ti6Al4V powder with this machine, which was subjected to surface treatment by chemical etching. An object with certain initially adopted assumptions, i.e. shape and geometric dimensions, was finally achieved, which perfectly matches the patient bone recesses. The scaffold created was subjected to micro-and spectroscopic examinations.

Regioselective synthesis of 7,8-dihydroimidazo[5,1-c][1,2,4]triazine-3,6(2H,4H-dione derivatives: A new drug-like heterocyclic scaffold

Directory of Open Access Journals (Sweden)

Nikolay T. Tzvetkov

2012-09-01

Full Text Available Dihydroimidazo[5,1-c][1,2,4]triazine-3,6(2H,4H-dione derivatives were prepared by successive N3- and N1-alkylation of hydantoins, followed by regioselective thionation and subsequent cyclization under mild conditions. In a final alkylation step a further substituent may be introduced. The synthetic strategy allows broad structural variation of this new drug-like heterobicyclic scaffold. In addition to extensive NMR and MS analyses, the structure of one derivative was confirmed by X-ray crystallography.

Preparation and characterization of biohybrid poly (3-hydroxybutyrate-co-3-hydroxyvalerate) based nanofibrous scaffolds

Science.gov (United States)

Kouhi, Monireh; Fathi, Mohammadhossein; Venugopal, Jayarama Reddy; Shamanian, Morteza; Ramakrishna, Seeram

2018-01-01

Development of bioengineered scaffolds for bone tissue regeneration is a growing area of research, especially those involving biodegradable electrospun nanofibers incorporated with ceramic nanoparticles, since they can mimic the extracellular matrix (ECM) of the native bone. In the current study, a biocomposite nanofibrous scaffolds consisting of poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), fibrinogen (FIB) and bredigite (BR) nanoparticles was fabricated through electrospinning. The morphological, chemical and mechanical characteristics of the resultant scaffolds were studied by using field emission-scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FTIR) and tensile tester, respectively. It was found that PHBV-FIB-BR scaffolds exhibited enhanced tensile strength and young modulus compared to PHBV and PHBV-FIB scaffolds. In addition, the measurements of the water contact angle suggested that incorporation of bredigite and fibrinogen into PHBV could improve the hydrophilicity of the composites. The results of bioactivity assessment performed in the simulated body fluid (SBF) demonstrated that the presence of the bredigite nanoparticles induced the nucleation and growth of apatite layer on the surface of PHBV-FIB-BR scaffold in SBF. Furthermore, the ion concentration changes of SBF solutions with composite scaffolds showed that PHBV-FIB-BR scaffolds released Ca and Si ions, which can stimulate osteoblast proliferation. The results of cell culture studies revealed the higher osteoblast proliferation, mineralization and differentiation on PHBV-FIB-BR and PHBV-FIB scaffolds than on PHBV. Our results suggest that PHBV-FIB-BR nanofibrous scaffold would be a promising candidate as a biocomposite nanofibrous scaffold material for tissue engineering applications.

Design, Synthesis and the Biological Evaluation of New 1,3-Thiazolidine-4-ones Based on the 4-Amino-2,3-dimethyl-1-phenyl-3-pyrazolin-5-one Scaffold

Directory of Open Access Journals (Sweden)

Maria Apotrosoaei

2014-09-01

Full Text Available New thiazolidine-4-one derivatives based on the 4-aminophenazone (4-amino-2,3-dimethyl-1-phenyl-3-pyrazolin-5-one scaffold have been synthesized as potential anti-inflammatory drugs. The pyrazoline derivatives are known especially for their antipyretic, analgesic and anti-inflammatory effects, but recently there were synthesized new compounds with important antioxidant, antiproliferative, anticancer and antidiabetic activities. The beneficial effects of these compounds are explained by nonselective inhibition of cyclooxygenase izoenzymes, but also by their potential scavenging ability for reactive oxygen and nitrogen species. The structure of the new compounds was proved using spectroscopic methods (FR-IR, 1H-NMR, 13C-NMR, MS. The in vitro antioxidant potential of the synthesized compounds was evaluated according to the ferric reducing antioxidant power, phosphomolydenum reducing antioxidant power, DPPH and ABTS radical scavenging assays. The chemical modulation of 4-aminophenazone (6 through linkage to thiazolidine-propanoic acid derivatives 5a–l led to improved antioxidant potential, all derivatives 7a–l being more active than phenazone. The most active compounds are the derivatives 7e, and 7k, which showed the higher antioxidant effect depending on the antioxidant assay considered.

Mesoporous bioactive glass functionalized 3D Ti-6Al-4V scaffolds with improved surface bioactivity

NARCIS (Netherlands)

Ye, Xiaotong; Leeflang, M.A.; Wu, Chengtie; Chang, Jiang; Zhou, J.; Huan, Z.

2017-01-01

Porous Ti-6Al-4V scaffolds fabricated by means of selective laser melting (SLM),
having controllable geometrical features and preferable mechanical properties, have been developed as a class of biomaterials that hold promising potential for bone repair. However, the inherent bio-inertness of the

Histological evaluation of osteogenesis of 3D-printed poly-lactic-co-glycolic acid (PLGA) scaffolds in a rabbit model

Energy Technology Data Exchange (ETDEWEB)

Ge Zigang; Tian Xianfeng; Heng, Boon Chin; Fan, Victor; Yeo Jinfei; Cao Tong, E-mail: omscaot@nus.edu.s [Stem Cell Laboratory, Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, National University of Singapore, 5 Lower Kent Ridge Road, Singapore 119074 (Singapore)

2009-04-15

Utilizing a suitable combination of lactide and glycolide in a copolymer would optimize the degradation rate of a scaffold upon implantation in situ. Moreover, 3D printing technology enables customizing the shape of the scaffold to biometric data from CT and MRI scans. A previous in vitro study has shown that novel 3D-printed poly-lactic-co-glycolic acid (PLGA) scaffolds had good biocompatibility and mechanical properties comparable with human cancellous bone, while they could support proliferation and osteogenic differentiation of osteoblasts. Based on the previous study, this study evaluated PLGA scaffolds for bone regeneration within a rabbit model. The scaffolds were implanted at two sites on the same animal, within the periosteum and within bi-cortical bone defects on the iliac crest. Subsequently, the efficacy of bone regeneration within the implanted scaffolds was evaluated at 4, 12 and 24 weeks post-surgery through histological analysis. In both the intra-periosteum and iliac bone defect models, the implanted scaffolds facilitated new bone tissue formation and maturation over the time course of 24 weeks, even though there was initially observed to be little tissue ingrowth within the scaffolds at 4 weeks post-surgery. Hence, the 3D-printed porous PLGA scaffolds investigated in this study displayed good biocompatibility and are osteoconductive in both the intra-periosteum and iliac bone defect models. (communication)

Histological evaluation of osteogenesis of 3D-printed poly-lactic-co-glycolic acid (PLGA) scaffolds in a rabbit model

International Nuclear Information System (INIS)

Ge Zigang; Tian Xianfeng; Heng, Boon Chin; Fan, Victor; Yeo Jinfei; Cao Tong

2009-01-01

Utilizing a suitable combination of lactide and glycolide in a copolymer would optimize the degradation rate of a scaffold upon implantation in situ. Moreover, 3D printing technology enables customizing the shape of the scaffold to biometric data from CT and MRI scans. A previous in vitro study has shown that novel 3D-printed poly-lactic-co-glycolic acid (PLGA) scaffolds had good biocompatibility and mechanical properties comparable with human cancellous bone, while they could support proliferation and osteogenic differentiation of osteoblasts. Based on the previous study, this study evaluated PLGA scaffolds for bone regeneration within a rabbit model. The scaffolds were implanted at two sites on the same animal, within the periosteum and within bi-cortical bone defects on the iliac crest. Subsequently, the efficacy of bone regeneration within the implanted scaffolds was evaluated at 4, 12 and 24 weeks post-surgery through histological analysis. In both the intra-periosteum and iliac bone defect models, the implanted scaffolds facilitated new bone tissue formation and maturation over the time course of 24 weeks, even though there was initially observed to be little tissue ingrowth within the scaffolds at 4 weeks post-surgery. Hence, the 3D-printed porous PLGA scaffolds investigated in this study displayed good biocompatibility and are osteoconductive in both the intra-periosteum and iliac bone defect models. (communication)

Rapid prototyping for tissue-engineered bone scaffold by 3D printing and biocompatibility study.

Science.gov (United States)

He, Hui-Yu; Zhang, Jia-Yu; Mi, Xue; Hu, Yang; Gu, Xiao-Yu

2015-01-01

The prototyping of tissue-engineered bone scaffold (calcined goat spongy bone-biphasic ceramic composite/PVA gel) by 3D printing was performed, and the biocompatibility of the fabricated bone scaffold was studied. Pre-designed STL file was imported into the GXYZ303010-XYLE 3D printing system, and the tissue-engineered bone scaffold was fabricated by 3D printing using gel extrusion. Rabbit bone marrow stromal cells (BMSCs) were cultured in vitro and then inoculated to the sterilized bone scaffold obtained by 3D printing. The growth of rabbit BMSCs on the bone scaffold was observed under the scanning electron microscope (SEM). The effect of the tissue-engineered bone scaffold on the proliferation and differentiation of rabbit BMSCs using MTT assay. Universal testing machine was adopted to test the tensile strength of the bone scaffold. The leachate of the bone scaffold was prepared and injected into the New Zealand rabbits. Cytotoxicity test, acute toxicity test, pyrogenic test and intracutaneous stimulation test were performed to assess the biocompatibility of the bone scaffold. Bone scaffold manufactured by 3D printing had uniform pore size with the porosity of about 68.3%. The pores were well interconnected, and the bone scaffold showed excellent mechanical property. Rabbit BMSCs grew and proliferated on the surface of the bone scaffold after adherence. MTT assay indicated that the proliferation and differentiation of rabbit BMSCs on the bone scaffold did not differ significantly from that of the cells in the control. In vivo experiments proved that the bone scaffold fabricated by 3D printing had no acute toxicity, pyrogenic reaction or stimulation. Bone scaffold manufactured by 3D printing allows the rabbit BMSCs to adhere, grow and proliferate and exhibits excellent biomechanical property and high biocompatibility. 3D printing has a good application prospect in the prototyping of tissue-engineered bone scaffold.

Gelatin–PMVE/MA composite scaffold promotes expansion of embryonic stem cells

International Nuclear Information System (INIS)

Chhabra, Hemlata; Gupta, Priyanka; Verma, Paul J.; Jadhav, Sameer; Bellare, Jayesh R.

2014-01-01

We introduce a new composite scaffold of gelatin and polymethyl vinyl ether-alt-maleic anhydride (PMVE/MA) for expansion of embryonic stem cells (ESCs) in an in vitro environment. To optimize the scaffold, we prepared a gelatin scaffold (G) and three composite scaffolds namely GP-1, GP-2, and GP-3 with varying PMVE/MA concentrations (0.2–1%) and characterized them by scanning electron microscopy (SEM), swelling study, compression testing and FTIR. SEM micrographs revealed interconnected porous structure in all the scaffolds. The permissible hemolysis ratio and activation of platelets by scaffolds confirmed the hemocompatibility of scaffolds. Initial biocompatibility assessment of scaffolds was conducted using hepatocarcinoma (Hep G2) cells and adhesion, proliferation and infiltration of Hep G2 cells in depth of scaffolds were observed, proving the scaffold's biocompatibility. Further Oct4B2 mouse embryonic stem cells (mESCs), which harbor a green fluorescence protein transgene under regulatory control of the Oct4 promotor, were examined for expansion on scaffolds with MTT assay. The GP-2 scaffold demonstrated the best cell proliferation and was further explored for ESC adherence and infiltration in depth (SEM and confocal), and pluripotent state of mESCs was assessed with the expression of Oct4-GFP and stage-specific embryonic antigen-1 (SSEA-1). This study reports the first demonstration of biocompatibility of gelatin–PMVE/MA composite scaffold and presents this scaffold as a promising candidate for embryonic stem cell based tissue engineering. - Highlights: • Composite scaffolds of gelatin and PMVE/MA were prepared by freeze-drying method. • SEM micrographs showed porous structure in all scaffolds of varying pore dimension. • GP-2 composite exhibited better cellular response in comparison to other scaffolds. • mESCs proliferated and expressed Oct-4 and SSEA-1, when cultured on GP-2 scaffold

Gelatin–PMVE/MA composite scaffold promotes expansion of embryonic stem cells

Energy Technology Data Exchange (ETDEWEB)

Chhabra, Hemlata [Department of Chemical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai (India); Gupta, Priyanka [Department of Chemical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai (India); IITB-Monash Research Academy, Mumbai (India); Department of Chemical Engineering, Monash University, Melbourne (Australia); Verma, Paul J. [Turretfield Research Centre, South Australian Research and Development Institute, Rosedale, South Australia (Australia); Jadhav, Sameer; Bellare, Jayesh R. [Department of Chemical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai (India)

2014-04-01

We introduce a new composite scaffold of gelatin and polymethyl vinyl ether-alt-maleic anhydride (PMVE/MA) for expansion of embryonic stem cells (ESCs) in an in vitro environment. To optimize the scaffold, we prepared a gelatin scaffold (G) and three composite scaffolds namely GP-1, GP-2, and GP-3 with varying PMVE/MA concentrations (0.2–1%) and characterized them by scanning electron microscopy (SEM), swelling study, compression testing and FTIR. SEM micrographs revealed interconnected porous structure in all the scaffolds. The permissible hemolysis ratio and activation of platelets by scaffolds confirmed the hemocompatibility of scaffolds. Initial biocompatibility assessment of scaffolds was conducted using hepatocarcinoma (Hep G2) cells and adhesion, proliferation and infiltration of Hep G2 cells in depth of scaffolds were observed, proving the scaffold's biocompatibility. Further Oct4B2 mouse embryonic stem cells (mESCs), which harbor a green fluorescence protein transgene under regulatory control of the Oct4 promotor, were examined for expansion on scaffolds with MTT assay. The GP-2 scaffold demonstrated the best cell proliferation and was further explored for ESC adherence and infiltration in depth (SEM and confocal), and pluripotent state of mESCs was assessed with the expression of Oct4-GFP and stage-specific embryonic antigen-1 (SSEA-1). This study reports the first demonstration of biocompatibility of gelatin–PMVE/MA composite scaffold and presents this scaffold as a promising candidate for embryonic stem cell based tissue engineering. - Highlights: • Composite scaffolds of gelatin and PMVE/MA were prepared by freeze-drying method. • SEM micrographs showed porous structure in all scaffolds of varying pore dimension. • GP-2 composite exhibited better cellular response in comparison to other scaffolds. • mESCs proliferated and expressed Oct-4 and SSEA-1, when cultured on GP-2 scaffold.

Improved resolution of 3D printed scaffolds by shrinking.

Science.gov (United States)

Chia, Helena N; Wu, Benjamin M

2015-10-01

Three-dimensional printing (3DP) uses inkjet printheads to selectively deposit liquid binder to adjoin powder particles in a layer-by-layer fashion to create a computer-modeled 3D object. Two general approaches for 3DP have been described for biomedical applications (direct and indirect 3DP). The two approaches offer competing advantages, and both are limited by print resolution. This study describes a materials processing strategy to enhance 3DP resolution by controlled shrinking net-shape scaffolds. Briefly, porogen preforms are printed and infused with the desired monomer or polymer solution. After solidification or polymerization, the porogen is leached and the polymer is allowed to shrink by controlled drying. Heat treatment is performed to retain the dimensions against swelling forces. The main objective of this study is to determine the effects of polymer content and post-processing on dimension, microstructure, and thermomechanical properties of the scaffold. For polyethylene glycol diacrylate (PEG-DA), reducing polymer content corresponded with greater shrinkage with maximum shrinkage of ∼80 vol% at 20% vol% PEG-DA. The secondary heat treatment retains the microarchitecture and new dimensions of the scaffolds, even when the heat-treated scaffolds are immersed into water. To demonstrate shrinkage predictability, 3D components with interlocking positive and negative features were printed, processed, and fitted. This material processing strategy provides an alternative method to enhance the resolution of 3D scaffolds, for a wide range of polymers, without optimizing the binder-powder interaction physics to print each material combination. © 2014 Wiley Periodicals, Inc.

Towards 4D Printed Scaffolds for Tissue Engineering : Exploiting 3D Shape Memory Polymers to Deliver Time-Controlled Stimulus on Cultured Cells

NARCIS (Netherlands)

Hendrikson, Wilhelmus J.; Rouwkema, Jeroen; Clementi, Federico; van Blitterswijk, Clemens; Farè, Silvia; Moroni, Lorenzo

2017-01-01

Tissue engineering needs innovative solutions to better fit the requirements of a minimally invasive approach, providing at the same time instructive cues to cells. The use of shape memory polyurethane has been investigated by producing 4D scaffolds via additive manufacturing technology. Scaffolds

Inhibitor scaffold for the histone lysine demethylase KDM4C (JMJD2C)

DEFF Research Database (Denmark)

Leurs, Ulrike; Clausen, Rasmus P; Kristensen, Jesper L

2012-01-01

The human histone demethylases of the KDM4 (JMJD2) family have been associated to diseases such as prostate and breast cancer, as well as X-linked mental retardation. Therefore, these enzymes are considered oncogenes and their selective inhibition might be a possible therapeutic approach to treat...... cancer. Here we describe a heterocyclic ring system library screened against the histone demethylase KDM4C (JMJD2C) in the search for novel inhibitory scaffolds. A 4-hydroxypyrazole scaffold was identified as an inhibitor of KDM4C; this scaffold could be employed in the further development of novel...... therapeutics, as well as for the elucidation of the biological roles of KDM4C on epigenetic regulation....

3D Powder Printed Bioglass and β-Tricalcium Phosphate Bone Scaffolds

Directory of Open Access Journals (Sweden)

Michael Seidenstuecker

2017-12-01

Full Text Available The use of both bioglass (BG and β tricalcium phosphate (β-TCP for bone replacement applications has been studied extensively due to the materials’ high biocompatibility and ability to resorb when implanted in the body. 3D printing has been explored as a fast and versatile technique for the fabrication of porous bone scaffolds. This project investigates the effects of using different combinations of a composite BG and β-TCP powder for 3D printing of porous bone scaffolds. Porous 3D powder printed bone scaffolds of BG, β-TCP, 50/50 BG/β-TCP and 70/30 BG/β-TCP compositions were subject to a variety of characterization and biocompatibility tests. The porosity characteristics, surface roughness, mechanical strength, viability for cell proliferation, material cytotoxicity and in vitro bioactivity were assessed. The results show that the scaffolds can support osteoblast-like MG-63 cells growth both on the surface of and within the scaffold material and do not show alarming cytotoxicity; the porosity and surface characteristics of the scaffolds are appropriate. Of the two tested composite materials, the 70/30 BG/β-TCP scaffold proved to be superior in terms of biocompatibility and mechanical strength. The mechanical strength of the scaffolds makes them unsuitable for load bearing applications. However, they can be useful for other applications such as bone fillers.

3D printed porous ceramic scaffolds for bone tissue engineering: a review.

Science.gov (United States)

Wen, Yu; Xun, Sun; Haoye, Meng; Baichuan, Sun; Peng, Chen; Xuejian, Liu; Kaihong, Zhang; Xuan, Yang; Jiang, Peng; Shibi, Lu

2017-08-22

This study summarizes the recent research status and development of three-dimensional (3D)-printed porous ceramic scaffolds in bone tissue engineering. Recent literature on 3D-printed porous ceramic scaffolds was reviewed. Compared with traditional processing and manufacturing technologies, 3D-printed porous ceramic scaffolds have obvious advantages, such as enhancement of the controllability of the structure or improvement of the production efficiency. More sophisticated scaffolds were fabricated by 3D printing technology. 3D printed bioceramics have broad application prospects in bone tissue engineering. Through understanding the advantages and limitations of different 3D-printing approaches, new classes of bone graft substitutes can be developed.

Fabrication of scalable tissue engineering scaffolds with dual-pore microarchitecture by combining 3D printing and particle leaching

Energy Technology Data Exchange (ETDEWEB)

Mohanty, Soumyaranjan; Sanger, Kuldeep; Heiskanen, Arto [DTU Nanotech, Department of Micro- and Nanotechnology, Technical University of Denmark, Ørsteds Plads, DK-2800 Kgs. Lyngby (Denmark); Trifol, Jon; Szabo, Peter [Danish Polymer Centre, Department of Chemical and Biochemical Engineering, Søltofts Plads, Building 229, DK-2800 Kgs. Lyngby (Denmark); Dufva, Marin; Emnéus, Jenny [DTU Nanotech, Department of Micro- and Nanotechnology, Technical University of Denmark, Ørsteds Plads, DK-2800 Kgs. Lyngby (Denmark); Wolff, Anders, E-mail: anders.wolff@nanotech.dtu.dk [DTU Nanotech, Department of Micro- and Nanotechnology, Technical University of Denmark, Ørsteds Plads, DK-2800 Kgs. Lyngby (Denmark)

2016-04-01

Limitations in controlling scaffold architecture using traditional fabrication techniques are a problem when constructing engineered tissues/organs. Recently, integration of two pore architectures to generate dual-pore scaffolds with tailored physical properties has attracted wide attention in tissue engineering community. Such scaffolds features primary structured pores which can efficiently enhance nutrient/oxygen supply to the surrounding, in combination with secondary random pores, which give high surface area for cell adhesion and proliferation. Here, we present a new technique to fabricate dual-pore scaffolds for various tissue engineering applications where 3D printing of poly(vinyl alcohol) (PVA) mould is combined with salt leaching process. In this technique the sacrificial PVA mould, determining the structured pore architecture, was filled with salt crystals to define the random pore regions of the scaffold. After crosslinking the casted polymer the combined PVA-salt mould was dissolved in water. The technique has advantages over previously reported ones, such as automated assembly of the sacrificial mould, and precise control over pore architecture/dimensions by 3D printing parameters. In this study, polydimethylsiloxane and biodegradable poly(ϵ-caprolactone) were used for fabrication. However, we show that this technique is also suitable for other biocompatible/biodegradable polymers. Various physical and mechanical properties of the dual-pore scaffolds were compared with control scaffolds with either only structured or only random pores, fabricated using previously reported methods. The fabricated dual-pore scaffolds supported high cell density, due to the random pores, in combination with uniform cell distribution throughout the scaffold, and higher cell proliferation and viability due to efficient nutrient/oxygen transport through the structured pores. In conclusion, the described fabrication technique is rapid, inexpensive, scalable, and compatible

Fabrication of scalable tissue engineering scaffolds with dual-pore microarchitecture by combining 3D printing and particle leaching

International Nuclear Information System (INIS)

Mohanty, Soumyaranjan; Sanger, Kuldeep; Heiskanen, Arto; Trifol, Jon; Szabo, Peter; Dufva, Marin; Emnéus, Jenny; Wolff, Anders

2016-01-01

Limitations in controlling scaffold architecture using traditional fabrication techniques are a problem when constructing engineered tissues/organs. Recently, integration of two pore architectures to generate dual-pore scaffolds with tailored physical properties has attracted wide attention in tissue engineering community. Such scaffolds features primary structured pores which can efficiently enhance nutrient/oxygen supply to the surrounding, in combination with secondary random pores, which give high surface area for cell adhesion and proliferation. Here, we present a new technique to fabricate dual-pore scaffolds for various tissue engineering applications where 3D printing of poly(vinyl alcohol) (PVA) mould is combined with salt leaching process. In this technique the sacrificial PVA mould, determining the structured pore architecture, was filled with salt crystals to define the random pore regions of the scaffold. After crosslinking the casted polymer the combined PVA-salt mould was dissolved in water. The technique has advantages over previously reported ones, such as automated assembly of the sacrificial mould, and precise control over pore architecture/dimensions by 3D printing parameters. In this study, polydimethylsiloxane and biodegradable poly(ϵ-caprolactone) were used for fabrication. However, we show that this technique is also suitable for other biocompatible/biodegradable polymers. Various physical and mechanical properties of the dual-pore scaffolds were compared with control scaffolds with either only structured or only random pores, fabricated using previously reported methods. The fabricated dual-pore scaffolds supported high cell density, due to the random pores, in combination with uniform cell distribution throughout the scaffold, and higher cell proliferation and viability due to efficient nutrient/oxygen transport through the structured pores. In conclusion, the described fabrication technique is rapid, inexpensive, scalable, and compatible

Modeling and Reconstruction of Micro-structured 3D Chitosan/Gelatin Porous Scaffolds Using Micro-CT

Science.gov (United States)

Gong, Haibo; Li, Dichen; He, Jiankang; Liu, Yaxiong; Lian, Qin; Zhao, Jinna

2008-09-01

Three dimensional (3D) channel networks are the key to promise the uniform distribution of nutrients inside 3D hepatic tissue engineering scaffolds and prompt elimination of metabolic products out of the scaffolds. 3D chitosan/gelatin porous scaffolds with predefined internal channels were fabricated and a combination of light microscope, laser confocal microscopy and micro-CT were employed to characterize the structure of porous scaffolds. In order to evaluate the flow field distribution inside the micro-structured 3D scaffolds, a computer reconstructing method based on Micro-CT was proposed. According to this evaluating method, a contrast between 3D porous scaffolds with and without predefined internal channels was also performed to assess scaffolds' fluid characters. Results showed that the internal channel of the 3D scaffolds formed the 3D fluid channel network; the uniformity of flow field distribution of the scaffolds fabricated in this paper was better than the simple porous scaffold without micro-fluid channels.

Hybrid 3D-2D printing for bone scaffolds fabrication

Science.gov (United States)

Seleznev, V. A.; Prinz, V. Ya

2017-02-01

It is a well-known fact that bone scaffold topography on micro- and nanometer scale influences the cellular behavior. Nano-scale surface modification of scaffolds allows the modulation of biological activity for enhanced cell differentiation. To date, there has been only a limited success in printing scaffolds with micro- and nano-scale features exposed on the surface. To improve on the currently available imperfect technologies, in our paper we introduce new hybrid technologies based on a combination of 2D (nano imprint) and 3D printing methods. The first method is based on using light projection 3D printing and simultaneous 2D nanostructuring of each of the layers during the formation of the 3D structure. The second method is based on the sequential integration of preliminarily created 2D nanostructured films into a 3D printed structure. The capabilities of the developed hybrid technologies are demonstrated with the example of forming 3D bone scaffolds. The proposed technologies can be used to fabricate complex 3D micro- and nanostructured products for various fields.

Anti-biofouling 3D porous systems: the blend effect of oxazoline-based oligomers on chitosan scaffolds.

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Correia, Vanessa G; Coelho, Margarida; Barroso, Telma; Raje, Vivek P; Bonifácio, Vasco D B; Casimiro, Teresa; Pinho, Mariana G; Aguiar-Ricardo, Ana

2013-01-01

The production, characterization and anti-biofouling activity of 3D porous scaffolds combining different blends of chitosan and oxazoline-based antimicrobial oligomers is reported. The incorporation of ammonium quaternized oligo(2-oxazoline)s into the composition of the scaffold enhances the stability of the chitosan scaffold under physiological conditions as well as its ability to repel protein adsorption. The blended scaffolds showed mean pore sizes in the range of 18-32 μm, a good pore interconnectivity and high porosity, as well as a large surface area, ultimate key features for anti-biofouling applications. Bovine serum albumin (BSA) adhesion profiles showed that the composition of the scaffolds plays a critical role in the chitosan-oligooxazoline system. Oligobisoxazoline-enriched scaffolds (20% w/w, CB8020) decreased protein adsorption (BSA) by up to 70%. Moreover, 1 mg of CB8020 was able to kill 99.9% of Escherichia coli cells upon contact, demonstrating its potential as promising material for production of tailored non-fouling 3D structures to be used in the construction of novel devices with applications in the biomedical field and water treatment processes.

3D silicon doped hydroxyapatite scaffolds decorated with Elastin-like Recombinamers for bone regenerative medicine.

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Vila, Mercedes; García, Ana; Girotti, Alessandra; Alonso, Matilde; Rodríguez-Cabello, Jose Carlos; González-Vázquez, Arlyng; Planell, Josep A; Engel, Elisabeth; Buján, Julia; García-Honduvilla, Natalio; Vallet-Regí, María

2016-11-01

The current study reports on the manufacturing by rapid prototyping technique of three-dimensional (3D) scaffolds based on silicon substituted hydroxyapatite with Elastin-like Recombinamers (ELRs) functionalized surfaces. Silicon doped hydroxyapatite (Si-HA), with Ca 10 (PO 4 ) 5.7 (SiO 4 ) 0.3 (OH) 1.7 h 0.3 nominal formula, was surface functionalized with two different types of polymers designed by genetic engineering: ELR-RGD that contain cell attachment specific sequences and ELR-SN A 15/RGD with both hydroxyapatite and cells domains that interact with the inorganic phase and with the cells, respectively. These hybrid materials were subjected to in vitro assays in order to clarify if the ELRs coating improved the well-known biocompatible and bone regeneration properties of calcium phosphates materials. The in vitro tests showed that there was a total and homogeneous colonization of the 3D scaffolds by Bone marrow Mesenchymal Stromal Cells (BMSCs). In addition, the BMSCs were viable and able to proliferate and differentiate into osteoblasts. Bone tissue engineering is an area of increasing interest because its main applications are directly related to the rising life expectancy of the population, which promotes higher rates of several bone pathologies, so innovative strategies are needed for bone tissue regeneration therapies. Here we use the rapid prototyping technology to allow moulding ceramic 3D scaffolds and we use different bio-polymers for the functionalization of their surfaces in order to enhance the biological response. Combining the ceramic material (silicon doped hydroxyapatite, Si-HA) and the Elastin like Recombinamers (ELRs) polymers with the presence of the integrin-mediate adhesion domain alone or in combination with SNA15 peptide that possess high affinity for hydroxyapatite, provided an improved Bone marrow Mesenchymal Stromal Cells (BMSCs) differentiation into osteoblastic linkage. Copyright © 2016 Acta Materialia Inc. Published by Elsevier

Chondrogenesis of infrapatellar fat pad derived adipose stem cells in 3D printed chitosan scaffold.

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Ye, Ken; Felimban, Raed; Traianedes, Kathy; Moulton, Simon E; Wallace, Gordon G; Chung, Johnson; Quigley, Anita; Choong, Peter F M; Myers, Damian E

2014-01-01

Infrapatellar fat pad adipose stem cells (IPFP-ASCs) have been shown to harbor chondrogenic potential. When combined with 3D polymeric structures, the stem cells provide a source of stem cells to engineer 3D tissues for cartilage repair. In this study, we have shown human IPFP-ASCs seeded onto 3D printed chitosan scaffolds can undergo chondrogenesis using TGFβ3 and BMP6. By week 4, a pearlescent, cartilage-like matrix had formed that penetrated the top layers of the chitosan scaffold forming a 'cap' on the scaffold. Chondrocytic morphology showed typical cells encased in extracellular matrix which stained positively with toluidine blue. Immunohistochemistry demonstrated positive staining for collagen type II and cartilage proteoglycans, as well as collagen type I. Real time PCR analysis showed up-regulation of collagen type II, aggrecan and SOX9 genes when IPFP-ASCs were stimulated by TGFβ3 and BMP6. Thus, IPFP-ASCs can successfully undergo chondrogenesis using TGFβ3 and BMP6 and the cartilage-like tissue that forms on the surface of 3D-printed chitosan scaffold may prove useful as an osteochondral graft.

Chondrogenesis of infrapatellar fat pad derived adipose stem cells in 3D printed chitosan scaffold.

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Ken Ye

Full Text Available Infrapatellar fat pad adipose stem cells (IPFP-ASCs have been shown to harbor chondrogenic potential. When combined with 3D polymeric structures, the stem cells provide a source of stem cells to engineer 3D tissues for cartilage repair. In this study, we have shown human IPFP-ASCs seeded onto 3D printed chitosan scaffolds can undergo chondrogenesis using TGFβ3 and BMP6. By week 4, a pearlescent, cartilage-like matrix had formed that penetrated the top layers of the chitosan scaffold forming a 'cap' on the scaffold. Chondrocytic morphology showed typical cells encased in extracellular matrix which stained positively with toluidine blue. Immunohistochemistry demonstrated positive staining for collagen type II and cartilage proteoglycans, as well as collagen type I. Real time PCR analysis showed up-regulation of collagen type II, aggrecan and SOX9 genes when IPFP-ASCs were stimulated by TGFβ3 and BMP6. Thus, IPFP-ASCs can successfully undergo chondrogenesis using TGFβ3 and BMP6 and the cartilage-like tissue that forms on the surface of 3D-printed chitosan scaffold may prove useful as an osteochondral graft.

Bioactive polymeric–ceramic hybrid 3D scaffold for application in bone tissue regeneration

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Torres, A.L.; Gaspar, V.M.; Serra, I.R.; Diogo, G.S.; Fradique, R. [CICS-UBI — Health Sciences Research Centre, University of Beira Interior, Av. Infante D. Henrique, 6200-506 Covilhã (Portugal); Silva, A.P. [CAST-UBI — Centre for Aerospace Science and Technologies, University of Beira Interior, Calçada Fonte do Lameiro, 6201-001 Covilhã (Portugal); Correia, I.J., E-mail: icorreia@ubi.pt [CICS-UBI — Health Sciences Research Centre, University of Beira Interior, Av. Infante D. Henrique, 6200-506 Covilhã (Portugal)

2013-10-01

The regeneration of large bone defects remains a challenging scenario from a therapeutic point of view. In fact, the currently available bone substitutes are often limited by poor tissue integration and severe host inflammatory responses, which eventually lead to surgical removal. In an attempt to address these issues, herein we evaluated the importance of alginate incorporation in the production of improved and tunable β-tricalcium phosphate (β-TCP) and hydroxyapatite (HA) three-dimensional (3D) porous scaffolds to be used as temporary templates for bone regeneration. Different bioceramic combinations were tested in order to investigate optimal scaffold architectures. Additionally, 3D β-TCP/HA vacuum-coated with alginate, presented improved compressive strength, fracture toughness and Young's modulus, to values similar to those of native bone. The hybrid 3D polymeric–bioceramic scaffolds also supported osteoblast adhesion, maturation and proliferation, as demonstrated by fluorescence microscopy. To the best of our knowledge this is the first time that a 3D scaffold produced with this combination of biomaterials is described. Altogether, our results emphasize that this hybrid scaffold presents promising characteristics for its future application in bone regeneration. - Graphical abstract: B-TCP:HA–alginate hybrid 3D porous scaffolds for application in bone regeneration. - Highlights: • The produced hybrid 3D scaffolds are prone to be applied in bone tissue engineering. • Alginate coated 3D scaffolds present high mechanical and biological properties. • In vitro assays for evaluation of human osteoblast cell attachment in the presence of the scaffolds • The hybrid 3D scaffolds present suitable mechanical and biological properties for use in bone regenerative medicine.

Bioactive polymeric–ceramic hybrid 3D scaffold for application in bone tissue regeneration

International Nuclear Information System (INIS)

Torres, A.L.; Gaspar, V.M.; Serra, I.R.; Diogo, G.S.; Fradique, R.; Silva, A.P.; Correia, I.J.

2013-01-01

The regeneration of large bone defects remains a challenging scenario from a therapeutic point of view. In fact, the currently available bone substitutes are often limited by poor tissue integration and severe host inflammatory responses, which eventually lead to surgical removal. In an attempt to address these issues, herein we evaluated the importance of alginate incorporation in the production of improved and tunable β-tricalcium phosphate (β-TCP) and hydroxyapatite (HA) three-dimensional (3D) porous scaffolds to be used as temporary templates for bone regeneration. Different bioceramic combinations were tested in order to investigate optimal scaffold architectures. Additionally, 3D β-TCP/HA vacuum-coated with alginate, presented improved compressive strength, fracture toughness and Young's modulus, to values similar to those of native bone. The hybrid 3D polymeric–bioceramic scaffolds also supported osteoblast adhesion, maturation and proliferation, as demonstrated by fluorescence microscopy. To the best of our knowledge this is the first time that a 3D scaffold produced with this combination of biomaterials is described. Altogether, our results emphasize that this hybrid scaffold presents promising characteristics for its future application in bone regeneration. - Graphical abstract: B-TCP:HA–alginate hybrid 3D porous scaffolds for application in bone regeneration. - Highlights: • The produced hybrid 3D scaffolds are prone to be applied in bone tissue engineering. • Alginate coated 3D scaffolds present high mechanical and biological properties. • In vitro assays for evaluation of human osteoblast cell attachment in the presence of the scaffolds • The hybrid 3D scaffolds present suitable mechanical and biological properties for use in bone regenerative medicine

Layer-by-layer assembly of peptide based bioorganic–inorganic hybrid scaffolds and their interactions with osteoblastic MC3T3-E1 cells

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Romanelli, Steven M.; Fath, Karl R.; Phekoo, Aruna P.; Knoll, Grant A.; Banerjee, Ipsita A.

2015-01-01

In this work we have developed a new family of biocomposite scaffolds for bone tissue regeneration by utilizing self-assembled fluorenylmethyloxycarbonyl protected Valyl-cetylamide (FVC) nanoassemblies as templates. To tailor the assemblies for enhanced osteoblast attachment and proliferation, we incorporated (a) Type I collagen, (b) a hydroxyapatite binding peptide sequence (EDPHNEVDGDK) derived from dentin sialophosphoprotein and (c) the osteoinductive bone morphogenetic protein-4 (BMP-4) to the templates by layer-by-layer assembly. The assemblies were then incubated with hydroxyapatite nanocrystals blended with varying mass percentages of TiO 2 nanoparticles and coated with alginate to form three dimensional scaffolds for potential applications in bone tissue regeneration. The morphology was examined by TEM and SEM and the binding interactions were probed by FITR spectroscopy. The scaffolds were found to be non-cytotoxic, adhered to mouse preosteoblast MC3T3-E1 cells and promoted osteogenic differentiation as indicated by the results obtained by alkaline phosphatase assay. Furthermore, they were found to be biodegradable and possessed inherent antibacterial capability. Thus, we have developed a new family of tissue-engineered biocomposite scaffolds with potential applications in bone regeneration. - Highlights: • Fmoc-val-cetylamide assemblies were used as templates. • Collagen, a short dentin sialophosphoprotein derived sequence and BMP-4 were incorporated. • Hydroxyapatite–TiO 2 nanocomposite blends and alginate were incorporated. • The 3D scaffold biocomposites adhered to preosteoblasts and promoted osteoblast differentiation. • The biocomposites also displayed antimicrobial activity

Layer-by-layer assembly of peptide based bioorganic–inorganic hybrid scaffolds and their interactions with osteoblastic MC3T3-E1 cells

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Romanelli, Steven M. [Fordham University Department of Chemistry, 441 East Fordham Road, Bronx, NY 10458 (United States); Fath, Karl R. [The City University of New York, Queens College, Department of Biology, 65-30 Kissena Blvd, Flushing, NY 11367 (United States); The Graduate Center, The City University of New York, 365 Fifth Avenue, NY 10016 (United States); Phekoo, Aruna P. [The City University of New York, Queens College, Department of Biology, 65-30 Kissena Blvd, Flushing, NY 11367 (United States); Knoll, Grant A. [Fordham University Department of Chemistry, 441 East Fordham Road, Bronx, NY 10458 (United States); Banerjee, Ipsita A., E-mail: banerjee@fordham.edu [Fordham University Department of Chemistry, 441 East Fordham Road, Bronx, NY 10458 (United States)

2015-06-01

In this work we have developed a new family of biocomposite scaffolds for bone tissue regeneration by utilizing self-assembled fluorenylmethyloxycarbonyl protected Valyl-cetylamide (FVC) nanoassemblies as templates. To tailor the assemblies for enhanced osteoblast attachment and proliferation, we incorporated (a) Type I collagen, (b) a hydroxyapatite binding peptide sequence (EDPHNEVDGDK) derived from dentin sialophosphoprotein and (c) the osteoinductive bone morphogenetic protein-4 (BMP-4) to the templates by layer-by-layer assembly. The assemblies were then incubated with hydroxyapatite nanocrystals blended with varying mass percentages of TiO{sub 2} nanoparticles and coated with alginate to form three dimensional scaffolds for potential applications in bone tissue regeneration. The morphology was examined by TEM and SEM and the binding interactions were probed by FITR spectroscopy. The scaffolds were found to be non-cytotoxic, adhered to mouse preosteoblast MC3T3-E1 cells and promoted osteogenic differentiation as indicated by the results obtained by alkaline phosphatase assay. Furthermore, they were found to be biodegradable and possessed inherent antibacterial capability. Thus, we have developed a new family of tissue-engineered biocomposite scaffolds with potential applications in bone regeneration. - Highlights: • Fmoc-val-cetylamide assemblies were used as templates. • Collagen, a short dentin sialophosphoprotein derived sequence and BMP-4 were incorporated. • Hydroxyapatite–TiO{sub 2} nanocomposite blends and alginate were incorporated. • The 3D scaffold biocomposites adhered to preosteoblasts and promoted osteoblast differentiation. • The biocomposites also displayed antimicrobial activity.

Oxygen Plasma Treatment on 3D-Printed Chitosan/Gelatin/Hydroxyapatite Scaffolds for Bone Tissue Engineering.

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Lee, Chang-Min; Yang, Seong-Won; Jung, Sang-Chul; Kim, Byung-Hoon

2017-04-01

The 3D hydroxyapatite/gelatin/chitosan composite scaffolds were fabricated by 3D printing technique. The scaffolds were treated by oxygen plasma to improve the bioactivity and its surface characterization and in vitro cell culture were investigated. The scaffolds exhibited the good porosity and interconnectivity of pores. After oxygen plasma etching, roughness and wettability on the scaffolds surface are increased. Plasma treated scaffolds showed higher proliferation than that of untreated scaffolds. Oxygen plasma treatment could be used as potential tool to enhance the biocompatibility on the 3D composite scaffolds.

3D Tissue Scaffold Printing On Custom Artificial Bone Applications

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Betül ALDEMİR

2015-01-01

Full Text Available Production of defect-matching scaffolds is the most critical step in custom artificial bone applications. Three dimensional printing (3DP is one of the best techniques particularly for custom designs on artificial bone applications because of the high controllability and design independency. Our long-term aim is to implant an artificial custom bone that is cultured with patient's own mesenchymal stem cells after determining defect architecture on patient's bone by using CT-scan and printing that defect-matching 3D scaffold with appropriate nontoxic materials. In this study, preliminary results of strength and cytotoxicity measurements of 3D printed scaffolds with modified calcium sulfate compositepowder (MCSCP were presented. CAD designs were created and MCSCP were printed by a 3D printer (3DS, Visijet, PXL Core. Some samples were covered with salt solution in order to harden the samples. MCSCP and salt coated MCSCP were the two experimental groups in this study. Cytotoxicity and mechanical experiments were performed after surface examination withscanning electron microscope (SEM and light microscope. Tension tests were performed for MCSCP and salt coated MCSCP samples. The 3D scaffolds were sterilized with ethylene oxide gas sterilizer, ventilated and conditioned with DMEM (10% FBS. L929 mouse fibroblast cells were cultured on scaffolds (3 repetitive and cell viability was determined using MTT analysis. According to the mechanical results, the MCSCP group stands until average 71,305 N, while salt coated MCSCP group stands until 21,328N. Although the strength difference between two groups is statistically significant (p=0.001, Mann-Whitney U, elastic modulus is not (MCSCP=1,186Pa, salt coated MCSCP=1,169Pa, p=0.445. Cell viability (MTT analysis results on day 1, 3, and 5 demonstrated thatscaffolds hadno toxic effect to the L929 mouse fibroblast cells. Consequently, 3D printed samples with MCSCP could potentially be a strong alternative

3D Scaffolds with Different Stiffness but the Same Microstructure for Bone Tissue Engineering.

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Chen, Guobao; Dong, Chanjuan; Yang, Li; Lv, Yonggang

2015-07-29

A growing body of evidence has shown that extracellular matrix (ECM) stiffness can modulate stem cell adhesion, proliferation, migration, differentiation, and signaling. Stem cells can feel and respond sensitively to the mechanical microenvironment of the ECM. However, most studies have focused on classical two-dimensional (2D) or quasi-three-dimensional environments, which cannot represent the real situation in vivo. Furthermore, most of the current methods used to generate different mechanical properties invariably change the fundamental structural properties of the scaffolds (such as morphology, porosity, pore size, and pore interconnectivity). In this study, we have developed novel three-dimensional (3D) scaffolds with different degrees of stiffness but the same 3D microstructure that was maintained by using decellularized cancellous bone. Mixtures of collagen and hydroxyapatite [HA: Ca10(PO4)6(OH)2] with different proportions were coated on decellularized cancellous bone to vary the stiffness (local stiffness, 13.00 ± 5.55 kPa, 13.87 ± 1.51 kPa, and 37.7 ± 19.6 kPa; bulk stiffness, 6.74 ± 1.16 kPa, 8.82 ± 2.12 kPa, and 23.61 ± 8.06 kPa). Microcomputed tomography (μ-CT) assay proved that there was no statistically significant difference in the architecture of the scaffolds before or after coating. Cell viability, osteogenic differentiation, cell recruitment, and angiogenesis were determined to characterize the scaffolds and evaluate their biological responses in vitro and in vivo. The in vitro results indicate that the scaffolds developed in this study could sustain adhesion and growth of rat mesenchymal stem cells (MSCs) and promote their osteogenic differentiation. The in vivo results further demonstrated that these scaffolds could help to recruit MSCs from subcutaneous tissue, induce them to differentiate into osteoblasts, and provide the 3D environment for angiogenesis. These findings showed that the method we developed can build scaffolds with

Fabrication of scalable tissue engineering scaffolds with dual-pore microarchitecture by combining 3D printing and particle leaching.

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Mohanty, Soumyaranjan; Sanger, Kuldeep; Heiskanen, Arto; Trifol, Jon; Szabo, Peter; Dufva, Marin; Emnéus, Jenny; Wolff, Anders

2016-04-01

Limitations in controlling scaffold architecture using traditional fabrication techniques are a problem when constructing engineered tissues/organs. Recently, integration of two pore architectures to generate dual-pore scaffolds with tailored physical properties has attracted wide attention in tissue engineering community. Such scaffolds features primary structured pores which can efficiently enhance nutrient/oxygen supply to the surrounding, in combination with secondary random pores, which give high surface area for cell adhesion and proliferation. Here, we present a new technique to fabricate dual-pore scaffolds for various tissue engineering applications where 3D printing of poly(vinyl alcohol) (PVA) mould is combined with salt leaching process. In this technique the sacrificial PVA mould, determining the structured pore architecture, was filled with salt crystals to define the random pore regions of the scaffold. After crosslinking the casted polymer the combined PVA-salt mould was dissolved in water. The technique has advantages over previously reported ones, such as automated assembly of the sacrificial mould, and precise control over pore architecture/dimensions by 3D printing parameters. In this study, polydimethylsiloxane and biodegradable poly(ϵ-caprolactone) were used for fabrication. However, we show that this technique is also suitable for other biocompatible/biodegradable polymers. Various physical and mechanical properties of the dual-pore scaffolds were compared with control scaffolds with either only structured or only random pores, fabricated using previously reported methods. The fabricated dual-pore scaffolds supported high cell density, due to the random pores, in combination with uniform cell distribution throughout the scaffold, and higher cell proliferation and viability due to efficient nutrient/oxygen transport through the structured pores. In conclusion, the described fabrication technique is rapid, inexpensive, scalable, and compatible

3D-Printed Bioactive Ca3SiO5 Bone Cement Scaffolds with Nano Surface Structure for Bone Regeneration.

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Yang, Chen; Wang, Xiaoya; Ma, Bing; Zhu, Haibo; Huan, Zhiguang; Ma, Nan; Wu, Chengtie; Chang, Jiang

2017-02-22

Silicate bioactive materials have been widely studied for bone regeneration because of their eminent physicochemical properties and outstanding osteogenic bioactivity, and different methods have been developed to prepare porous silicate bioactive ceramics scaffolds for bone-tissue engineering applications. Among all of these methods, the 3D-printing technique is obviously the most efficient way to control the porous structure. However, 3D-printed bioceramic porous scaffolds need high-temperature sintering, which will cause volume shrinkage and reduce the controllability of the pore structure accuracy. Unlike silicate bioceramic, bioactive silicate cements such as tricalcium silicate (Ca 3 SiO 5 and C 3 S) can be self-set in water to obtain high mechanical strength under mild conditions. Another advantage of using C 3 S to prepare 3D scaffolds is the possibility of simultaneous drug loading. Herein, we, for the first time, demonstrated successful preparation of uniform 3D-printed C 3 S bone cement scaffolds with controllable 3D structure at room temperature. The scaffolds were loaded with two model drugs and showed a loading location controllable drug-release profile. In addition, we developed a surface modification process to create controllable nanotopography on the surface of pore wall of the scaffolds, which showed activity to enhance rat bone-marrow stem cells (rBMSCs) attachment, spreading, and ALP activities. The in vivo experiments revealed that the 3D-printed C 3 S bone cement scaffolds with nanoneedle-structured surfaces significantly improved bone regeneration, as compared to pure C 3 S bone cement scaffolds, suggesting that 3D-printed C 3 S bone cement scaffolds with controllable nanotopography surface are bioactive implantable biomaterials for bone repair.

Functionalized 3-(benzofuran-2-yl-5-(4-methoxyphenyl-4,5-dihydro-1H-pyrazole scaffolds: A new class of antimicrobials and antioxidants

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Javarappa Rangaswamy

2017-05-01

Full Text Available A new class of functionalized 3-(benzofuran-2-yl-5-(4-methoxyphenyl-4,5-dihydro-1H-pyrazole scaffolds (4a–q was synthesized by a four step reaction in good yields. Initially, o-alkyl derivative of salicyaldehyde (1 readily furnished corresponding 2-acetyl benzofuran (2 on treatment with potassium tert-butoxide (t-BuOK in the presence of molecular sieves. Further, Claisen–Schmidt condensation reaction with 4-methoxy benzaldehyde and hydrazine hydrate followed by coupling of benzoyl chlorides afforded target compounds (4a–q. Representative of the synthesized compounds was characterized by IR, 1H NMR, 13C NMR, mass, elemental analysis and evaluated for antimicrobial and antioxidant activities. The results gathered are allowed to conclude that, all newly synthesized analogues exhibit a certain degree of antimicrobial and antioxidant activities. Among the analogues, compounds (4h and (4j showed an excellent antimicrobial activity in the well plate method. Meanwhile, compounds (4e–f, (4l and (4p showed good antioxidant activity, whereas compound (4g and (4q displayed dominant antioxidant efficacy compared to standard butylated hydroxy anisole (BHA.

Chitosan-alginate 3D scaffolds as a mimic of the glioma tumor microenvironment.

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Kievit, Forrest M; Florczyk, Stephen J; Leung, Matthew C; Veiseh, Omid; Park, James O; Disis, Mary L; Zhang, Miqin

2010-08-01

Despite recent advances in the understanding of its cell biology, glioma remains highly lethal. Development of effective therapies requires a cost-effective in vitro tumor model that more accurately resembles the in vivo tumor microenvironment as standard two-dimensional (2D) tissue culture conditions do so poorly. Here we report on the use of a three-dimensional (3D) chitosan-alginate (CA) scaffold to serve as an extracellular matrix that promotes the conversion of cultured cancer cells to a more malignant in vivo-like phenotype. Human U-87 MG and U-118 MG glioma cells and rat C6 glioma cells were chosen for the study. In vitro tumor cell proliferation and secretion of factors that promote tumor malignancy, including VEGF, MMP-2, fibronectin, and laminin, were assessed. The scaffolds pre-cultured with U-87 MG and C6 cells were then implanted into nude mice to evaluate tumor growth and blood vessel recruitment compared to the standard 2D cell culture and 3D Matrigel matrix xenograft controls. Our results indicate that while the behavior of C6 cells showed minimal differences due to their highly malignant and invasive nature, U-87 MG and U-118 MG cells exhibited notably higher malignancy when cultured in CA scaffolds. CA scaffolds provide a 3D microenvironment for glioma cells that is more representative of the in vivo tumor, thus can serve as a more effective platform for development and study of anticancer therapeutics. This unique CA scaffold platform may offer a valuable alternative strategy to the time-consuming and costly animal studies for a wide variety of experimental designs. Copyright 2010 Elsevier Ltd. All rights reserved.

Graphene Oxide Hybridized nHAC/PLGA Scaffolds Facilitate the Proliferation of MC3T3-E1 Cells

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Liang, Chunyong; Luo, Yongchao; Yang, Guodong; Xia, Dan; Liu, Lei; Zhang, Xiaomin; Wang, Hongshui

2018-01-01

Biodegradable porous biomaterial scaffolds play a critical role in bone regeneration. In this study, the porous nano-hydroxyapatite/collagen/poly(lactic-co-glycolic acid)/graphene oxide (nHAC/PLGA/GO) composite scaffolds containing different amount of GO were fabricated by freeze-drying method. The results show that the synthesized scaffolds possess a three-dimensional porous structure. GO slightly improves the hydrophilicity of the scaffolds and reinforces their mechanical strength. Young's modulus of the 1.5 wt% GO incorporated scaffold is greatly increased compared to the control sample. The in vitro experiments show that the nHAC/PLGA/GO (1.5 wt%) scaffolds significantly cell adhesion and proliferation of osteoblast cells (MC3T3-E1). This present study indicates that the nHAC/PLGA/GO scaffolds have excellent cytocompatibility and bone regeneration ability, thus it has high potential to be used as scaffolds in the field of bone tissue engineering.

3D printed hyperelastic "bone" scaffolds and regional gene therapy: A novel approach to bone healing.

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Alluri, Ram; Jakus, Adam; Bougioukli, Sofia; Pannell, William; Sugiyama, Osamu; Tang, Amy; Shah, Ramille; Lieberman, Jay R

2018-04-01

The purpose of this study was to evaluate the viability of human adipose-derived stem cells (ADSCs) transduced with a lentiviral (LV) vector to overexpress bone morphogenetic protein-2 (BMP-2) loaded onto a novel 3D printed scaffold. Human ADSCs were transduced with a LV vector carrying the cDNA for BMP-2. The transduced cells were loaded onto a 3D printed Hyperelastic "Bone" (HB) scaffold. In vitro BMP-2 production was assessed using enzyme-linked immunosorbent assay analysis. The ability of ADSCs loaded on the HB scaffold to induce in vivo bone formation in a hind limb muscle pouch model was assessed in the following groups: ADSCs transduced with LV-BMP-2, LV-green fluorescent protein, ADSCs alone, and empty HB scaffolds. Bone formation was assessed using radiographs, histology and histomorphometry. Transduced ADSCs BMP-2 production on the HB scaffold at 24 hours was similar on 3D printed HB scaffolds versus control wells with transduced cells alone, and continued to increase after 1 and 2 weeks of culture. Bone formation was noted in LV-BMP-2 animals on plain radiographs at 2 and 4 weeks after implantation; no bone formation was noted in the other groups. Histology demonstrated that the LV-BMP-2 group was the only group that formed woven bone and the mean bone area/tissue area was significantly greater when compared with the other groups. 3D printed HB scaffolds are effective carriers for transduced ADSCs to promote bone repair. The combination of gene therapy and tissue engineered scaffolds is a promising multidisciplinary approach to bone repair with significant clinical potential. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 1104-1110, 2018. © 2018 Wiley Periodicals, Inc.

TGF-β3 encapsulated PLCL scaffold by a supercritical CO2-HFIP co-solvent system for cartilage tissue engineering.

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Kim, Su Hee; Kim, Soo Hyun; Jung, Youngmee

2015-05-28

Mimicking the native tissue microenvironment is critical for effective tissue regeneration. Mechanical cues and sustained biological cues are important factors, particularly in load-bearing tissues such as articular cartilage or bone. Carriers including hydrogels and nanoparticles have been investigated to achieve sustained release of protein drugs. However, it is difficult to apply such carriers alone as scaffolds for cartilage regeneration because of their weak mechanical properties, and they must be combined with other biomaterials that have adequate mechanical strength. In this study, we developed the multifunctional scaffold which has similar mechanical properties to those of native cartilage and encapsulates TGF-β3 for chondrogenesis. In our previous work, we confirmed that poly(lactide-co-caprolacton) (PLCL) did not foam when exposed to supercritical CO2 below 45°C. Here, we used a supercritical carbon dioxide (scCO2)-1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) co-solvent system to facilitate processing under mild conditions because high temperature causes protein denaturation and decreases bioactivity of the protein. This processing made it possible to fabricate a TGF-β3 encapsulated elastic porous PLCL scaffold at 37°C. We investigated the tissue regeneration efficiency of the TGF-β3 encapsulated PLCL scaffold using human adipose-derived stem cells (ADSCs) in vitro and in vivo (Groups; i. PLCL scaffold+Fibrin gel+TGF-β3, ii. TGF-β3 encapsulated PLCL scaffold+Fibrin gel, iii. TGF-β3 encapsulated PLCL scaffold). We evaluated the chondrogenic abilities of the scaffolds at 4, 8, and 12weeks after subcutaneous implantation of the constructs in immune-deficient mice. Based on TGF-β3 release studies, we confirmed that TGF-β3 molecules were released by 8weeks and remained in the PLCL matrix. Explants of TGF-β3 encapsulated scaffolds by a co-solvent system exhibited distinct improvement in the compressive E-modulus and deposition of extracellular matrix

Cell-secreted extracellular matrix formation and differentiation of adipose-derived stem cells in 3D alginate scaffolds with tunable properties.

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Guneta, Vipra; Loh, Qiu Li; Choong, Cleo

2016-05-01

Three dimensional (3D) alginate scaffolds with tunable mechanical and structural properties are explored for investigating the effect of the scaffold properties on stem cell behavior and extracellular matrix (ECM) formation. Varying concentrations of crosslinker (20 - 60%) are used to tune the stiffness, porosity, and the pore sizes of the scaffolds post-fabrication. Enhanced cell proliferation and adipogenesis occur in scaffolds with 3.52 ± 0.59 kPa stiffness, 87.54 ± 18.33% porosity and 68.33 ± 0.88 μm pore size. On the other hand, cells in scaffolds with stiffness greater than 11.61 ± 1.74 kPa, porosity less than 71.98 ± 6.25%, and pore size less than 64.15 ± 4.34 μm preferentially undergo osteogenesis. When cultured in differentiation media, adipose-derived stem cells (ASCs) undergoing terminal adipogenesis in 20% firming buffer (FB) scaffolds and osteogenesis in 40% and 60% FB scaffolds show the highest secretion of collagen as compared to other groups of scaffolds. Overall, this study demonstrates the three-way relationship between 3D scaffolds, ECM composition, and stem cell differentiation. © 2016 Wiley Periodicals, Inc.

3D X-Ray Nanotomography of Cells Grown on Electrospun Scaffolds.

Science.gov (United States)

Bradley, Robert S; Robinson, Ian K; Yusuf, Mohammed

2017-02-01

Here, it is demonstrated that X-ray nanotomography with Zernike phase contrast can be used for 3D imaging of cells grown on electrospun polymer scaffolds. The scaffold fibers and cells are simultaneously imaged, enabling the influence of scaffold architecture on cell location and morphology to be studied. The high resolution enables subcellular details to be revealed. The X-ray imaging conditions were optimized to reduce scan times, making it feasible to scan multiple regions of interest in relatively large samples. An image processing procedure is presented which enables scaffold characteristics and cell location to be quantified. The procedure is demonstrated by comparing the ingrowth of cells after culture for 3 and 6 days. © 2016 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

3D-printed bioceramic scaffolds with antibacterial and osteogenic activity.

Science.gov (United States)

Zhang, Yongliang; Zhai, Dong; Xu, Mengchi; Yao, Qingqiang; Zhu, Huiying; Chang, Jiang; Wu, Chengtie

2017-06-20

Bacterial infection poses a significant risk with the wide application of bone graft materials. Designing bone grafts with good antibacterial performance and excellent bone-forming activity is of particular significance for bone tissue engineering. In our study, a 3D printing method was used to prepare β-tricalcium phosphate (β-TCP) bioceramic scaffolds. Silver (Ag) nanoparticles were uniformly dispersed on graphene oxide (GO) to form a homogeneous nanocomposite (named Ag@GO) with different Ag-to-graphene oxide mass ratios, with this being synthesized via the liquid chemical reduction approach. Ag@GO nanocomposites were successfully modified on the β-TCP scaffolds by a simple soaking method to achieve bifunctional biomaterials with antibacterial and osteogenic activity. The prepared scaffolds possessed a connected network with triangle pore morphology and the surfaces of the β-TCP scaffolds were uniformly modified by the Ag@GO nanocomposite layers. The Ag content in the scaffolds was controlled by changing the coating times and concentration of the Ag@GO nanocomposites. The antibacterial activity of the scaffolds was assessed with Gram-negative bacteria (Escherichia coli, E. coli). The results demonstrated that the scaffolds with Ag@GO nanocomposites presented excellent antibacterial activity. In addition, the scaffolds coated with Ag@GO nanocomposites conspicuously accelerated the osteogenic differentiation of rabbit bone marrow stromal cells by improving their alkaline phosphatase activity and bone-related gene expression (osteopontin, runt-related transcription factor 2, osteocalcin and bone sialoprotein). This study demonstrates that bifunctional scaffolds with a combination of antibacterial and osteogenic activity can be achieved for the reconstruction of large-bone defects while preventing or treating infections.

Rapid 3D printing of anatomically accurate and mechanically heterogeneous aortic valve hydrogel scaffolds

International Nuclear Information System (INIS)

Hockaday, L A; Kang, K H; Colangelo, N W; Cheung, P Y C; Duan, B; Wu, J; Bonassar, L J; Butcher, J T; Malone, E; Lipson, H; Girardi, L N; Chu, C C

2012-01-01

The aortic valve exhibits complex three-dimensional (3D) anatomy and heterogeneity essential for the long-term efficient biomechanical function. These are, however, challenging to mimic in de novo engineered living tissue valve strategies. We present a novel simultaneous 3D printing/photocrosslinking technique for rapidly engineering complex, heterogeneous aortic valve scaffolds. Native anatomic and axisymmetric aortic valve geometries (root wall and tri-leaflets) with 12–22 mm inner diameters (ID) were 3D printed with poly-ethylene glycol-diacrylate (PEG-DA) hydrogels (700 or 8000 MW) supplemented with alginate. 3D printing geometric accuracy was quantified and compared using Micro-CT. Porcine aortic valve interstitial cells (PAVIC) seeded scaffolds were cultured for up to 21 days. Results showed that blended PEG-DA scaffolds could achieve over tenfold range in elastic modulus (5.3±0.9 to 74.6±1.5 kPa). 3D printing times for valve conduits with mechanically contrasting hydrogels were optimized to 14 to 45 min, increasing linearly with conduit diameter. Larger printed valves had greater shape fidelity (93.3±2.6, 85.1±2.0 and 73.3±5.2% for 22, 17 and 12 mm ID porcine valves; 89.1±4.0, 84.1±5.6 and 66.6±5.2% for simplified valves). PAVIC seeded scaffolds maintained near 100% viability over 21 days. These results demonstrate that 3D hydrogel printing with controlled photocrosslinking can rapidly fabricate anatomical heterogeneous valve conduits that support cell engraftment. (paper)

Interdependency and phosphorylation of KIF4 and condensin I are essential for organization of chromosome scaffold.

Directory of Open Access Journals (Sweden)

Rawin Poonperm

Full Text Available Kinesin family member 4 (KIF4 and condensins I and II are essential chromosomal proteins for chromosome organization by locating primarily to the chromosome scaffold. However, the mechanism of how KIF4 and condensins localize to the chromosome scaffold is poorly understood. Here, we demonstrate a close relationship between the chromosome localization of KIF4 and condensin I, but not condensin II, and show that KIF4 and condensin I assist each other for stable scaffold formation by forming a stable complex. Moreover, phosphorylation of KIF4 and condensin I by Aurora B and polo-like kinase 1 (Plk1 is important for KIF4 and condensin I localization to the chromosome. Aurora B activity facilitates the targeting of KIF4 and condensin I to the chromosome, whereas Plk1 activity promotes the dissociation of these proteins from the chromosome. Thus, the interdependency between KIF4 and condensin I, and their phosphorylation states play important roles in chromosome scaffold organization during mitosis.

Interdependency and phosphorylation of KIF4 and condensin I are essential for organization of chromosome scaffold.

Science.gov (United States)

Poonperm, Rawin; Takata, Hideaki; Uchiyama, Susumu; Fukui, Kiichi

2017-01-01

Kinesin family member 4 (KIF4) and condensins I and II are essential chromosomal proteins for chromosome organization by locating primarily to the chromosome scaffold. However, the mechanism of how KIF4 and condensins localize to the chromosome scaffold is poorly understood. Here, we demonstrate a close relationship between the chromosome localization of KIF4 and condensin I, but not condensin II, and show that KIF4 and condensin I assist each other for stable scaffold formation by forming a stable complex. Moreover, phosphorylation of KIF4 and condensin I by Aurora B and polo-like kinase 1 (Plk1) is important for KIF4 and condensin I localization to the chromosome. Aurora B activity facilitates the targeting of KIF4 and condensin I to the chromosome, whereas Plk1 activity promotes the dissociation of these proteins from the chromosome. Thus, the interdependency between KIF4 and condensin I, and their phosphorylation states play important roles in chromosome scaffold organization during mitosis.

Soft chitosan microbeads scaffold for 3D functional neuronal networks.

Science.gov (United States)

Tedesco, Maria Teresa; Di Lisa, Donatella; Massobrio, Paolo; Colistra, Nicolò; Pesce, Mattia; Catelani, Tiziano; Dellacasa, Elena; Raiteri, Roberto; Martinoia, Sergio; Pastorino, Laura

2018-02-01

The availability of 3D biomimetic in vitro neuronal networks of mammalian neurons represents a pivotal step for the development of brain-on-a-chip experimental models to study neuronal (dys)functions and particularly neuronal connectivity. The use of hydrogel-based scaffolds for 3D cell cultures has been extensively studied in the last years. However, limited work on biomimetic 3D neuronal cultures has been carried out to date. In this respect, here we investigated the use of a widely popular polysaccharide, chitosan (CHI), for the fabrication of a microbead based 3D scaffold to be coupled to primary neuronal cells. CHI microbeads were characterized by optical and atomic force microscopies. The cell/scaffold interaction was deeply characterized by transmission electron microscopy and by immunocytochemistry using confocal microscopy. Finally, a preliminary electrophysiological characterization by micro-electrode arrays was carried out. Copyright © 2017 Elsevier Ltd. All rights reserved.

Fabrication of computationally designed scaffolds by low temperature 3D printing

International Nuclear Information System (INIS)

Castilho, Miguel; Dias, Marta; Fernandes, Paulo; Pires, Inês; Gouveia, Barbara; Rodrigues, Jorge; Gbureck, Uwe; Groll, Jürgen; Vorndran, Elke

2013-01-01

The development of artificial bone substitutes that mimic the properties of bone and simultaneously promote the desired tissue regeneration is a current issue in bone tissue engineering research. An approach to create scaffolds with such characteristics is based on the combination of novel design and additive manufacturing processes. The objective of this work is to characterize the microstructural and the mechanical properties of scaffolds developed by coupling both topology optimization and a low temperature 3D printing process. The scaffold design was obtained using a topology optimization approach to maximize the permeability with constraints on the mechanical properties. This procedure was studied to be suitable for the fabrication of a cage prototype for tibial tuberosity advancement application, which is one of the most recent and promising techniques to treat cruciate ligament rupture in dogs. The microstructural and mechanical properties of the scaffolds manufactured by reacting α/β-tricalcium phosphate with diluted phosphoric acid were then assessed experimentally and the scaffolds strength reliability was determined. The results demonstrate that the low temperature 3D printing process is a reliable option to create synthetic scaffolds with tailored properties, and when coupled with topology optimization design it can be a powerful tool for the fabrication of patient-specific bone implants. (paper)

Multifunctional chitosan/polyvinyl pyrrolidone/45S5 Bioglass® scaffolds for MC3T3-E1 cell stimulation and drug release

Energy Technology Data Exchange (ETDEWEB)

Yao, Qingqing [Institute of Advanced Materials for Nano-Bio Applications, School of Ophthalmology & Optometry, Wenzhou Medical University, 270 Xueyuan Xi Road, Wenzhou, Zhejiang 325027 (China); Li, Wei [Institute of Biomaterials, Department of Materials Science and Engineering, University of Erlangen-Nuremberg, Cauerstrasse 6, Erlangen 91058 (Germany); Yu, Shanshan; Ma, Liwei [Institute of Advanced Materials for Nano-Bio Applications, School of Ophthalmology & Optometry, Wenzhou Medical University, 270 Xueyuan Xi Road, Wenzhou, Zhejiang 325027 (China); Jin, Dayong [Institute for Biomedical Materials and Devices, Faculty of Science, University of Technology Sydney, NSW 2007 (Australia); Advanced Cytometry Labs, ARC Center of Excellence for Nanoscale BioPhotonics, Macquarie University, Sydney, NSW 2109 (Australia); Boccaccini, Aldo R., E-mail: Aldo.Boccaccini@ww.uni-erlangen.de [Institute of Biomaterials, Department of Materials Science and Engineering, University of Erlangen-Nuremberg, Cauerstrasse 6, Erlangen 91058 (Germany); Liu, Yong, E-mail: yongliu1980@hotmail.com [Institute of Advanced Materials for Nano-Bio Applications, School of Ophthalmology & Optometry, Wenzhou Medical University, 270 Xueyuan Xi Road, Wenzhou, Zhejiang 325027 (China); Advanced Cytometry Labs, ARC Center of Excellence for Nanoscale BioPhotonics, Macquarie University, Sydney, NSW 2109 (Australia)

2015-11-01

Novel chitosan–polyvinyl pyrrolidone/45S5 Bioglass® (CS-PVP/BG) scaffolds were prepared via foam replication and chemical cross-linking techniques. The pristine BG, CS-PVP coated BG and genipin cross-linked CS-PVP/BG (G-CS-PVP/BG) scaffolds were synthesized and characterized in terms of chemical composition, physical structure and morphology respectively. Resistance to enzymatic degradation of the scaffold is improved significantly with the use of genipin cross-linked CS-PVP. The bio-effects of scaffolds on MC3T3-E1 osteoblast-like cells were evaluated by studying cell viability, adhesion and proliferation. The CCK-8 assay shows that cell viability on the resulting G-CS-PVP/BG scaffold is improved obviously after cross-linking of genipin. Cell skeleton images exhibit that well-stretched F-actin bundles are obtained on the G-CS-PVP/BG scaffold. SEM results present significant improvement on the cell adhesion and proliferation for cells cultured on the G-CS-PVP/BG scaffold. The drug release performance on the as-synthesized scaffold was studied in a phosphate buffered saline (PBS) solution. Vancomycin is found to be released in burst fashion within 24 h from the pristine BG scaffold, however, the release period from the G-CS-PVP/BG scaffold is enhanced to 7 days, indicating improved drug release properties of the G-CS-PVP/BG scaffold. Our results suggest that the G-CS-PVP/BG scaffolds possess promising physicochemical properties, sustained drug release capability and good biocompatibility for MC3T3-E1 cells' proliferation and adhesion, suggesting their potential applications in areas such as MC3T3-E1 cell stimulation and bone tissue engineering. - Highlights: • Novel genipi–chitosan–polyvinyl pyrrolidone/45S5 Bioglass® scaffolds are prepared. • Resistance to enzymatic degradation of the scaffold is improved significantly. • The resulting scaffold shows enhanced MC3T3-E1 cell adhesion and proliferation. • Release of antibiotic vancomycin from the

Multifunctional chitosan/polyvinyl pyrrolidone/45S5 Bioglass® scaffolds for MC3T3-E1 cell stimulation and drug release

International Nuclear Information System (INIS)

Yao, Qingqing; Li, Wei; Yu, Shanshan; Ma, Liwei; Jin, Dayong; Boccaccini, Aldo R.; Liu, Yong

2015-01-01

Novel chitosan–polyvinyl pyrrolidone/45S5 Bioglass® (CS-PVP/BG) scaffolds were prepared via foam replication and chemical cross-linking techniques. The pristine BG, CS-PVP coated BG and genipin cross-linked CS-PVP/BG (G-CS-PVP/BG) scaffolds were synthesized and characterized in terms of chemical composition, physical structure and morphology respectively. Resistance to enzymatic degradation of the scaffold is improved significantly with the use of genipin cross-linked CS-PVP. The bio-effects of scaffolds on MC3T3-E1 osteoblast-like cells were evaluated by studying cell viability, adhesion and proliferation. The CCK-8 assay shows that cell viability on the resulting G-CS-PVP/BG scaffold is improved obviously after cross-linking of genipin. Cell skeleton images exhibit that well-stretched F-actin bundles are obtained on the G-CS-PVP/BG scaffold. SEM results present significant improvement on the cell adhesion and proliferation for cells cultured on the G-CS-PVP/BG scaffold. The drug release performance on the as-synthesized scaffold was studied in a phosphate buffered saline (PBS) solution. Vancomycin is found to be released in burst fashion within 24 h from the pristine BG scaffold, however, the release period from the G-CS-PVP/BG scaffold is enhanced to 7 days, indicating improved drug release properties of the G-CS-PVP/BG scaffold. Our results suggest that the G-CS-PVP/BG scaffolds possess promising physicochemical properties, sustained drug release capability and good biocompatibility for MC3T3-E1 cells' proliferation and adhesion, suggesting their potential applications in areas such as MC3T3-E1 cell stimulation and bone tissue engineering. - Highlights: • Novel genipi–chitosan–polyvinyl pyrrolidone/45S5 Bioglass® scaffolds are prepared. • Resistance to enzymatic degradation of the scaffold is improved significantly. • The resulting scaffold shows enhanced MC3T3-E1 cell adhesion and proliferation. • Release of antibiotic vancomycin from the

3D chitosan-gelatin-chondroitin porous scaffold improves osteogenic differentiation of mesenchymal stem cells

Energy Technology Data Exchange (ETDEWEB)

Machado, C B [Department of Biochemistry and Immunology, Institute of Biological Sciences, Federal University of Minas Gerais (Brazil); Ventura, J M G [Department of Ceramics and Glass Engineering, University of Aveiro (Portugal); Lemos, A F [Department of Ceramics and Glass Engineering, University of Aveiro (Portugal); Ferreira, J M F [Department of Ceramics and Glass Engineering, University of Aveiro (Portugal); Leite, M F [Department of Physiology and Biophysics, Institute of Biological Sciences, Federal University of Minas Gerais (Brazil); Goes, A M [Department of Biochemistry and Immunology, Institute of Biological Sciences, Federal University of Minas Gerais (Brazil)

2007-06-01

A porous 3D scaffold was developed to support and enhance the differentiation process of mesenchymal stem cells (MSC) into osteoblasts in vitro. The 3D scaffold was made with chitosan, gelatin and chondroitin and it was crosslinked by EDAC. The scaffold physicochemical properties were evaluated. SEM revealed the high porosity and interconnection of pores in the scaffold; rheological measurements show that the scaffold exhibits a characteristic behavior of strong gels. The elastic modulus found in compressive tests of the crosslinked scaffold was about 50 times higher than the non-crosslinked one. After 21 days, the 3D matrix submitted to hydrolytic degradation loses above 40% of its weight. MSC were collected from rat bone marrow and seeded in chitosan-gelatin-chondroitin 3D scaffolds and in 2D culture plates as well. MSC were differentiated into osteoblasts for 21 days. Cell proliferation and alkaline phosphatase activity were followed weekly during the osteogenic process. The osteogenic differentiation of MSC was improved in 3D culture as shown by MTT assay and alkaline phosphatase activity. On the 21st day, bone markers, osteopontin and osteocalcin, were detected by the PCR analysis. This study shows that the chitosan-gelatin-chondroitin 3D structure provides a good environment for the osteogenic process and enhances cellular proliferation.

3D chitosan-gelatin-chondroitin porous scaffold improves osteogenic differentiation of mesenchymal stem cells.

Science.gov (United States)

Machado, C B; Ventura, J M G; Lemos, A F; Ferreira, J M F; Leite, M F; Goes, A M

2007-06-01

A porous 3D scaffold was developed to support and enhance the differentiation process of mesenchymal stem cells (MSC) into osteoblasts in vitro. The 3D scaffold was made with chitosan, gelatin and chondroitin and it was crosslinked by EDAC. The scaffold physicochemical properties were evaluated. SEM revealed the high porosity and interconnection of pores in the scaffold; rheological measurements show that the scaffold exhibits a characteristic behavior of strong gels. The elastic modulus found in compressive tests of the crosslinked scaffold was about 50 times higher than the non-crosslinked one. After 21 days, the 3D matrix submitted to hydrolytic degradation loses above 40% of its weight. MSC were collected from rat bone marrow and seeded in chitosan-gelatin-chondroitin 3D scaffolds and in 2D culture plates as well. MSC were differentiated into osteoblasts for 21 days. Cell proliferation and alkaline phosphatase activity were followed weekly during the osteogenic process. The osteogenic differentiation of MSC was improved in 3D culture as shown by MTT assay and alkaline phosphatase activity. On the 21st day, bone markers, osteopontin and osteocalcin, were detected by the PCR analysis. This study shows that the chitosan-gelatin-chondroitin 3D structure provides a good environment for the osteogenic process and enhances cellular proliferation.

3D chitosan-gelatin-chondroitin porous scaffold improves osteogenic differentiation of mesenchymal stem cells

International Nuclear Information System (INIS)

Machado, C B; Ventura, J M G; Lemos, A F; Ferreira, J M F; Leite, M F; Goes, A M

2007-01-01

A porous 3D scaffold was developed to support and enhance the differentiation process of mesenchymal stem cells (MSC) into osteoblasts in vitro. The 3D scaffold was made with chitosan, gelatin and chondroitin and it was crosslinked by EDAC. The scaffold physicochemical properties were evaluated. SEM revealed the high porosity and interconnection of pores in the scaffold; rheological measurements show that the scaffold exhibits a characteristic behavior of strong gels. The elastic modulus found in compressive tests of the crosslinked scaffold was about 50 times higher than the non-crosslinked one. After 21 days, the 3D matrix submitted to hydrolytic degradation loses above 40% of its weight. MSC were collected from rat bone marrow and seeded in chitosan-gelatin-chondroitin 3D scaffolds and in 2D culture plates as well. MSC were differentiated into osteoblasts for 21 days. Cell proliferation and alkaline phosphatase activity were followed weekly during the osteogenic process. The osteogenic differentiation of MSC was improved in 3D culture as shown by MTT assay and alkaline phosphatase activity. On the 21st day, bone markers, osteopontin and osteocalcin, were detected by the PCR analysis. This study shows that the chitosan-gelatin-chondroitin 3D structure provides a good environment for the osteogenic process and enhances cellular proliferation

Designing of PLA scaffolds for bone tissue replacement fabricated by ordinary commercial 3D printer.

Science.gov (United States)

Gregor, Aleš; Filová, Eva; Novák, Martin; Kronek, Jakub; Chlup, Hynek; Buzgo, Matěj; Blahnová, Veronika; Lukášová, Věra; Bartoš, Martin; Nečas, Alois; Hošek, Jan

2017-01-01

The primary objective of Tissue engineering is a regeneration or replacement of tissues or organs damaged by disease, injury, or congenital anomalies. At present, Tissue engineering repairs damaged tissues and organs with artificial supporting structures called scaffolds. These are used for attachment and subsequent growth of appropriate cells. During the cell growth gradual biodegradation of the scaffold occurs and the final product is a new tissue with the desired shape and properties. In recent years, research workplaces are focused on developing scaffold by bio-fabrication techniques to achieve fast, precise and cheap automatic manufacturing of these structures. Most promising techniques seem to be Rapid prototyping due to its high level of precision and controlling. However, this technique is still to solve various issues before it is easily used for scaffold fabrication. In this article we tested printing of clinically applicable scaffolds with use of commercially available devices and materials. Research presented in this article is in general focused on "scaffolding" on a field of bone tissue replacement. Commercially available 3D printer and Polylactic acid were used to create originally designed and possibly suitable scaffold structures for bone tissue engineering. We tested printing of scaffolds with different geometrical structures. Based on the osteosarcoma cells proliferation experiment and mechanical testing of designed scaffold samples, it will be stated that it is likely not necessary to keep the recommended porosity of the scaffold for bone tissue replacement at about 90%, and it will also be clarified why this fact eliminates mechanical properties issue. Moreover, it is demonstrated that the size of an individual pore could be double the size of the recommended range between 0.2-0.35 mm without affecting the cell proliferation. Rapid prototyping technique based on Fused deposition modelling was used for the fabrication of designed scaffold

3D printing nano conductive multi-walled carbon nanotube scaffolds for nerve regeneration

Science.gov (United States)

Lee, Se-Jun; Zhu, Wei; Nowicki, Margaret; Lee, Grace; Nyoung Heo, Dong; Kim, Junghoon; Zuo, Yi Y.; Zhang, Lijie Grace

2018-02-01

Objective. Nanomaterials, such as carbon nanotubes (CNTs), have been introduced to modify the surface properties of scaffolds, thus enhancing the interaction between the neural cells and biomaterials. In addition to superior electrical conductivity, CNTs can provide nanoscale structures similar to those present in the natural neural environment. The primary objective of this study is to investigate the proliferative capability and differential potential of neural stem cells (NSCs) seeded on a CNT incorporated scaffold. Approach. Amine functionalized multi-walled carbon nanotubes (MWCNTs) were incorporated with a PEGDA polymer to provide enhanced electrical properties as well as nanofeatures on the surface of the scaffold. A stereolithography 3D printer was employed to fabricate a well-dispersed MWCNT-hydrogel composite neural scaffold with a tunable porous structure. 3D printing allows easy fabrication of complex 3D scaffolds with extremely intricate microarchitectures and controlled porosity. Main results. Our results showed that MWCNT-incorporated scaffolds promoted neural stem cell proliferation and early neuronal differentiation when compared to those scaffolds without the MWCNTs. Furthermore, biphasic pulse stimulation with 500 µA current promoted neuronal maturity quantified through protein expression analysis by quantitative polymerase chain reaction. Significance. Results of this study demonstrated that an electroconductive MWCNT scaffold, coupled with electrical stimulation, may have a synergistic effect on promoting neurite outgrowth for therapeutic application in nerve regeneration.

Discovery of a novel 2,4-dimethylquinoline-6-carboxamide M4 positive allosteric modulator (PAM) chemotype via scaffold hopping.

Science.gov (United States)

Long, Madeline F; Engers, Julie L; Chang, Sichen; Zhan, Xiaoyan; Weiner, Rebecca L; Luscombe, Vincent B; Rodriguez, Alice L; Cho, Hyekyung P; Niswender, Colleen M; Bridges, Thomas M; Conn, P Jeffrey; Engers, Darren W; Lindsley, Craig W

2017-11-15

This Letter details our efforts to replace the 3-amino moiety, an essential pharmacophore for M 4 PAM activity in most M 4 PAMs to date, within the thieno[2,3-b]pyridine core, as the β-amino carboxamide motif has been shown to engender poor solubility, varying degrees of P-gp efflux and represents a structural alert. A scaffold hopping exercise identified a novel 2,4-dimethylquinoline carboxamide core that provided M 4 PAM activity and good CNS penetration without an amino moiety. In addition, MacMillan photoredox catalysis chemistry was essential for construction of the 2,4-dimethylquinoline core. Copyright © 2017 Elsevier Ltd. All rights reserved.

Development and Characterization of Organic Electronic Scaffolds for Bone Tissue Engineering.

Science.gov (United States)

Iandolo, Donata; Ravichandran, Akhilandeshwari; Liu, Xianjie; Wen, Feng; Chan, Jerry K Y; Berggren, Magnus; Teoh, Swee-Hin; Simon, Daniel T

2016-06-01

Bones have been shown to exhibit piezoelectric properties, generating electrical potential upon mechanical deformation and responding to electrical stimulation with the generation of mechanical stress. Thus, the effects of electrical stimulation on bone tissue engineering have been extensively studied. However, in bone regeneration applications, only few studies have focused on the use of electroactive 3D biodegradable scaffolds at the interphase with stem cells. Here a method is described to combine the bone regeneration capabilities of 3D-printed macroporous medical grade polycaprolactone (PCL) scaffolds with the electrical and electrochemical capabilities of the conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT). PCL scaffolds have been highly effective in vivo as bone regeneration grafts, and PEDOT is a leading material in the field of organic bioelectronics, due to its stability, conformability, and biocompatibility. A protocol is reported for scaffolds functionalization with PEDOT, using vapor-phase polymerization, resulting in a conformal conducting layer. Scaffolds' porosity and mechanical stability, important for in vivo bone regeneration applications, are retained. Human fetal mesenchymal stem cells proliferation is assessed on the functionalized scaffolds, showing the cytocompatibility of the polymeric coating. Altogether, these results show the feasibility of the proposed approach to obtain electroactive scaffolds for electrical stimulation of stem cells for regenerative medicine. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

3D-printed scaffolds based on PLA/HA nanocomposites for trabecular bone reconstruction

Science.gov (United States)

Niaza, K. V.; Senatov, F. S.; Kaloshkin, S. D.; Maksimkin, A. V.; Chukov, D. I.

2016-08-01

In the present work porous PLA scaffolds filled with micro- and nano- HA were studied. Both composites with micro- and nano-HA were obtained by extrusion in the same conditions. Scaffolds were obtained by 3D-printing by fused filament fabrication method. Structure of porous scaffolds was pre-modeled by computer software. Compression and three - point flexural tests were used to study mechanical properties of the scaffolds.

In vitro characterization of 3D printed scaffolds aimed at bone tissue regeneration.

Science.gov (United States)

Boga, João C; Miguel, Sónia P; de Melo-Diogo, Duarte; Mendonça, António G; Louro, Ricardo O; Correia, Ilídio J

2018-05-01

The incidence of fractures and bone-related diseases like osteoporosis has been increasing due to aging of the world's population. Up to now, grafts and titanium implants have been the principal therapeutic approaches used for bone repair/regeneration. However, these types of treatment have several shortcomings, like limited availability, risk of donor-to-recipient infection and tissue morbidity. To overcome these handicaps, new 3D templates, capable of replicating the features of the native tissue, are currently being developed by researchers from the area of tissue engineering. These 3D constructs are able to provide a temporary matrix on which host cells can adhere, proliferate and differentiate. Herein, 3D cylindrical scaffolds were designed to mimic the natural architecture of hollow bones, and to allow nutrient exchange and bone neovascularization. 3D scaffolds were produced with tricalcium phosphate (TCP)/alginic acid (AA) using a Fab@home 3D printer. Furthermore, graphene oxide (GO) was incorporated into the structure of some scaffolds to further enhance their mechanical properties. The results revealed that the scaffolds incorporating GO displayed greater porosity, without impairing their mechanical properties. These scaffolds also presented a controlled swelling profile, enhanced biomineralization capacity and were able to increase the Alkaline Phosphatase (ALP) activity. Such characteristics make TCP/AA scaffolds functionalized with GO promising 3D constructs for bone tissue engineering applications. Copyright © 2018 Elsevier B.V. All rights reserved.

Preparation and characterization of cockle shell aragonite nanocomposite porous 3D scaffolds for bone repair

Directory of Open Access Journals (Sweden)

Saffanah Khuder Mahmood

2017-07-01

Full Text Available The demands for applicable tissue-engineered scaffolds that can be used to repair load-bearing segmental bone defects (SBDs is vital and in increasing demand. In this study, seven different combinations of 3 dimensional (3D novel nanocomposite porous structured scaffolds were fabricated to rebuild SBDs using an extraordinary blend of cockle shells (CaCo3 nanoparticles (CCN, gelatin, dextran and dextrin to structure an ideal bone scaffold with adequate degradation rate using the Freeze Drying Method (FDM and labeled as 5211, 5400, 6211, 6300, 7101, 7200 and 8100. The micron sized cockle shells powder obtained (75 µm was made into nanoparticles using mechano-chemical, top-down method of nanoparticles synthesis with the presence of the surfactant BS-12 (dodecyl dimethyl bataine. The phase purity and crystallographic structures, the chemical functionality and the thermal characterization of the scaffolds’ powder were recognized using X-Ray Diffractometer (XRD, Fourier transform infrared (FTIR spectrophotometer and Differential Scanning Calorimetry (DSC respectively. Characterizations of the scaffolds were assessed by Scanning Electron Microscopy (SEM, Degradation Manner, Water Absorption Test, Swelling Test, Mechanical Test and Porosity Test. Top-down method produced cockle shell nanoparticles having averagely range 37.8±3–55.2±9 nm in size, which were determined using Transmission Electron Microscope (TEM. A mainly aragonite form of calcium carbonate was identified in both XRD and FTIR for all scaffolds, while the melting (Tm and transition (Tg temperatures were identified using DSC with the range of Tm 62.4–75.5 °C and of Tg 230.6–232.5 °C. The newly prepared scaffolds were with the following characteristics: (i good biocompatibility and biodegradability, (ii appropriate surface chemistry and (iii highly porous, with interconnected pore network. Engineering analyses showed that scaffold 5211 possessed 3D interconnected homogenous

Evaluation of the effect of the degree of acetylation on the inflammatory response to 3D porous chitosan scaffolds.

Science.gov (United States)

Barbosa, Judite N; Amaral, Isabel F; Aguas, Artur P; Barbosa, Mário A

2010-04-01

The effect of the degree of acetylation (DA) of 3D chitosan (Ch) scaffolds on the inflammatory reaction was investigated. Chitosan porous scaffolds with DAs of 4 and 15% were implanted using a subcutaneous air-pouch model of inflammation. The initial acute inflammatory response was evaluated 24 and 48 h after implantation. To characterize the initial response, the recruitment and adhesion of inflammatory cells to the implant site was studied. The fibrous capsule formation and the infiltration of inflammatory cells within the scaffolds were evaluated for longer implantation times (2 and 4 weeks). Chitosan with DA 15% attracted the highest number of leukocytes to the implant site. High numbers of adherent inflammatory cells were also observed in this material. For longer implantation periods Ch scaffolds with a DA of 15% induced the formation of a thick fibrous capsule and a high infiltration of inflammatory cells within the scaffold. Our results indicate that the biological response to implanted Ch scaffolds was influenced by the DA. Chitosan with a DA of 15% induce a more intense inflammatory response when compared with DA 4% Ch. Because inflammation and healing are interrelated, this result may provide clues for the relative importance of acetyl and amine functional groups in tissue repair and regeneration.

3D-printed scaffolds based on PLA/HA nanocomposites for trabecular bone reconstruction

International Nuclear Information System (INIS)

Niaza, K V; Senatov, F S; Kaloshkin, S D; Maksimkin, A V; Chukov, D I

2016-01-01

In the present work porous PLA scaffolds filled with micro- and nano- HA were studied. Both composites with micro- and nano-HA were obtained by extrusion in the same conditions. Scaffolds were obtained by 3D-printing by fused filament fabrication method. Structure of porous scaffolds was pre-modeled by computer software. Compression and three - point flexural tests were used to study mechanical properties of the scaffolds. (paper)

Tantalum coating on porous Ti6Al4V scaffold using chemical vapor deposition and preliminary biological evaluation

Energy Technology Data Exchange (ETDEWEB)

Li, Xiang, E-mail: xiangliwj@sjtu.edu.cn [School of Mechanical Engineering, Shanghai Jiao Tong University, State Key Laboratory of Mechanical System and Vibration, Shanghai, 200240 (China); Wang, Lin [Institute of Orthopaedics, Xijing Hospital, The Fourth Military Medical University, Xi' an, 710032 (China); Yu, Xiaoming [The Institute of Metal Research, Chinese Academy of Sciences, Shenyang, 110016 (China); Feng, Yafei [Institute of Orthopaedics, Xijing Hospital, The Fourth Military Medical University, Xi' an, 710032 (China); Wang, Chengtao [School of Mechanical Engineering, Shanghai Jiao Tong University, State Key Laboratory of Mechanical System and Vibration, Shanghai, 200240 (China); Yang, Ke [The Institute of Metal Research, Chinese Academy of Sciences, Shenyang, 110016 (China); Su, Daniel [School of Mechanical Engineering, Shanghai Jiao Tong University, State Key Laboratory of Mechanical System and Vibration, Shanghai, 200240 (China)

2013-07-01

Porous tantalum (Ta), produced via chemical vapor deposition (CVD) of commercially pure Ta onto a vitreous carbon, is currently available for use in orthopedic applications. However, the relatively high manufacturing cost and the incapability to produce customized implant using medical image data have limited its application to gain widespread acceptance. In this study, Ta film was deposited on porous Ti6Al4V scaffolds using CVD technique. Digital microscopy and scanning electron microscopy indicated that the Ta coating evenly covered the entire scaffold structure. X-ray diffraction analysis showed that the coating consisted of α and β phases of Ta. Goat mesenchymal stem cells were seeded and cultured on the Ti6Al4V scaffolds with and without coating. The tetrazolium-based colorimetric assay exhibited better cell adhesion and proliferation on Ta-coated scaffolds compared with uncoated scaffolds. The porous scaffolds were subsequently implanted in goats for 12 weeks. Histological analysis revealed similar bone formation around the periphery of the coated and uncoated implants, but bone ingrowth is better within the Ta-coated scaffolds. To demonstrate the ability of producing custom implant for clinical applications via this technology, we designed and fabricated a porous Ti6Al4V scaffold with segmental mandibular shape derived from patient computerized tomography data. - Highlights: • Ta film was coated on porous Ti6Al4V scaffold using chemical vapor deposition. • Tantalum coating allowed for higher levels of cell adhesion and proliferation. • Better new bone formation occurred inside the tantalum-coated scaffolds. • Clinical image data was integrated with EBM to fabricate customized scaffold.

Tantalum coating on porous Ti6Al4V scaffold using chemical vapor deposition and preliminary biological evaluation

International Nuclear Information System (INIS)

Li, Xiang; Wang, Lin; Yu, Xiaoming; Feng, Yafei; Wang, Chengtao; Yang, Ke; Su, Daniel

2013-01-01

Porous tantalum (Ta), produced via chemical vapor deposition (CVD) of commercially pure Ta onto a vitreous carbon, is currently available for use in orthopedic applications. However, the relatively high manufacturing cost and the incapability to produce customized implant using medical image data have limited its application to gain widespread acceptance. In this study, Ta film was deposited on porous Ti6Al4V scaffolds using CVD technique. Digital microscopy and scanning electron microscopy indicated that the Ta coating evenly covered the entire scaffold structure. X-ray diffraction analysis showed that the coating consisted of α and β phases of Ta. Goat mesenchymal stem cells were seeded and cultured on the Ti6Al4V scaffolds with and without coating. The tetrazolium-based colorimetric assay exhibited better cell adhesion and proliferation on Ta-coated scaffolds compared with uncoated scaffolds. The porous scaffolds were subsequently implanted in goats for 12 weeks. Histological analysis revealed similar bone formation around the periphery of the coated and uncoated implants, but bone ingrowth is better within the Ta-coated scaffolds. To demonstrate the ability of producing custom implant for clinical applications via this technology, we designed and fabricated a porous Ti6Al4V scaffold with segmental mandibular shape derived from patient computerized tomography data. - Highlights: • Ta film was coated on porous Ti6Al4V scaffold using chemical vapor deposition. • Tantalum coating allowed for higher levels of cell adhesion and proliferation. • Better new bone formation occurred inside the tantalum-coated scaffolds. • Clinical image data was integrated with EBM to fabricate customized scaffold

Validation of scaffold design optimization in bone tissue engineering: finite element modeling versus designed experiments.

Science.gov (United States)

Uth, Nicholas; Mueller, Jens; Smucker, Byran; Yousefi, Azizeh-Mitra

2017-02-21

This study reports the development of biological/synthetic scaffolds for bone tissue engineering (TE) via 3D bioplotting. These scaffolds were composed of poly(L-lactic-co-glycolic acid) (PLGA), type I collagen, and nano-hydroxyapatite (nHA) in an attempt to mimic the extracellular matrix of bone. The solvent used for processing the scaffolds was 1,1,1,3,3,3-hexafluoro-2-propanol. The produced scaffolds were characterized by scanning electron microscopy, microcomputed tomography, thermogravimetric analysis, and unconfined compression test. This study also sought to validate the use of finite-element optimization in COMSOL Multiphysics for scaffold design. Scaffold topology was simplified to three factors: nHA content, strand diameter, and strand spacing. These factors affect the ability of the scaffold to bear mechanical loads and how porous the structure can be. Twenty four scaffolds were constructed according to an I-optimal, split-plot designed experiment (DE) in order to generate experimental models of the factor-response relationships. Within the design region, the DE and COMSOL models agreed in their recommended optimal nHA (30%) and strand diameter (460 μm). However, the two methods disagreed by more than 30% in strand spacing (908 μm for DE; 601 μm for COMSOL). Seven scaffolds were 3D-bioplotted to validate the predictions of DE and COMSOL models (4.5-9.9 MPa measured moduli). The predictions for these scaffolds showed relative agreement for scaffold porosity (mean absolute percentage error of 4% for DE and 13% for COMSOL), but were substantially poorer for scaffold modulus (51% for DE; 21% for COMSOL), partly due to some simplifying assumptions made by the models. Expanding the design region in future experiments (e.g., higher nHA content and strand diameter), developing an efficient solvent evaporation method, and exerting a greater control over layer overlap could allow developing PLGA-nHA-collagen scaffolds to meet the mechanical requirements for

Electrospun conductive nanofibrous scaffolds for engineering cardiac tissue and 3D bioactuators.

Science.gov (United States)

Wang, Ling; Wu, Yaobin; Hu, Tianli; Guo, Baolin; Ma, Peter X

2017-09-01

Mimicking the nanofibrous structure similar to extracellular matrix and conductivity for electrical propagation of native myocardium would be highly beneficial for cardiac tissue engineering and cardiomyocytes-based bioactuators. Herein, we developed conductive nanofibrous sheets with electrical conductivity and nanofibrous structure composed of poly(l-lactic acid) (PLA) blending with polyaniline (PANI) for cardiac tissue engineering and cardiomyocytes-based 3D bioactuators. Incorporating of varying contents of PANI from 0wt% to 3wt% into the PLA polymer, the electrospun nanofibrous sheets showed enhanced conductivity while maintaining the same fiber diameter. These PLA/PANI conductive nanofibrous sheets exhibited good cell viability and promoting effect on differentiation of H9c2 cardiomyoblasts in terms of maturation index and fusion index. Moreover, PLA/PANI nanofibrous sheets enhanced the cell-cell interaction, maturation and spontaneous beating of primary cardiomyocytes. Furthermore, the cardiomyocytes-laden PLA/PANI conductive nanofibrous sheets can form 3D bioactuators with tubular and folding shapes, and spontaneously beat with much higher frequency and displacement than that on cardiomyocytes-laden PLA nanofibrous sheets. Therefore, these PLA/PANI conductive nanofibrous sheets with conductivity and extracellular matrix like nanostructure demonstrated promising potential in cardiac tissue engineering and cardiomyocytes-based 3D bioactuators. Cardiomyocytes-based bioactuators have been paid more attention due to their spontaneous motion by integrating cardiomyocytes into polymer structures, but developing suitable scaffolds for bioactuators remains challenging. Electrospun nanofibrous scaffolds have been widely used in cardiac tissue engineering because they can mimic the extracellular matrix of myocardium. Developing conductive nanofibrous scaffolds by electrospinning would be beneficial for cardiomyocytes-based bioactuators, but such scaffolds have been

Clinical application of a 3D-printed scaffold in chronic wound treatment: a case series.

Science.gov (United States)

Sun, Haining; Lv, Huayao; Qiu, Fanghui; Sun, Duolun; Gao, Yue; Chen, Ning; Zheng, YongKe; Deng, Kunxue; Yang, Yaya; Zhang, Haitao; Xu, Tao; Ren, Dongni

2018-05-02

This case series evaluates the safety and effectiveness of 3D-printed scaffold in chronic wounds. The scaffold is a composite of natural and synthetic materials, and can be prepared in the form of powder or membrane. We recruited patients with pressure ulcera (PU) and/or a diabetic foot ulcers (DFU). We used two methods: 3D-printed scaffolds alone, or 3D-printing powder mixed with platelet-rich fibrinogen (PRF). Clinicians and patients were asked to rate the scaffold's ease of application and comfort during use. A total of five patients were recruited; four with a PU and one with a DFU. For the patient treated with the 3D-printed scaffold membrane (n=1), their PU healed in 28 days, and for patients treated with the 3D-printed scaffold powder (n=2), their PUs healed in 54 days. For the patients treated with the 3D-printing powder mixed with PRF (n=2), the patient with a PU healed in 11 days, and the patient with the DFU healed in 14 days. All clinicians rated the 3D-printed scaffold as 'easy' or 'very easy' to use, and patients rated their comfort during wear and at dressing change as 'good' or 'very good'. This study demonstrated that 3D-printed scaffold was convenient to use, have the potential to improve wound healing rates, and provided a safe and effective way for treating chronic wounds.

Stromal cell derived factor-1α (SDF-1α) directed chemoattraction of transiently CXCR4 overexpressing mesenchymal stem cells into functionalized three-dimensional biomimetic scaffolds

DEFF Research Database (Denmark)

Thieme, S; Ryser, Martin; Gentsch, Marcus

2009-01-01

Three-dimensional (3D) bone substitute material should not only serve as scaffold in large bone defects but also attract mesenchymal stem cells, a subset of bone marrow stromal cells (BMSCs) that are able to form new bone tissue. An additional crucial step is to attract BMSCs from the surface int...... invaded up to 250 mum into SDF-1alpha-releasing 3D scaffolds, whereas CXCR4-overexpressing BMSC invaded up to 500 mum within 5 days. Thus, the SDF-1alpha/CXCR4 chemoattraction system can be used to efficiently recruit BMSCs into SDF-1alpha-releasing 3D scaffolds in vitro and in vivo....

Proliferation and enrichment of CD133(+) glioblastoma cancer stem cells on 3D chitosan-alginate scaffolds.

Science.gov (United States)

Kievit, Forrest M; Florczyk, Stephen J; Leung, Matthew C; Wang, Kui; Wu, Jennifer D; Silber, John R; Ellenbogen, Richard G; Lee, Jerry S H; Zhang, Miqin

2014-11-01

Emerging evidence implicates cancer stem cells (CSCs) as primary determinants of the clinical behavior of human cancers, representing an ideal target for next-generation anti-cancer therapies. However CSCs are difficult to propagate in vitro, severely limiting the study of CSC biology and drug development. Here we report that growing cells from glioblastoma (GBM) cell lines on three dimensional (3D) porous chitosan-alginate (CA) scaffolds dramatically promotes the proliferation and enrichment of cells possessing the hallmarks of CSCs. CA scaffold-grown cells were found more tumorigenic in nude mouse xenografts than cells grown from monolayers. Growing in CA scaffolds rapidly promoted expression of genes involved in the epithelial-to-mesenchymal transition that has been implicated in the genesis of CSCs. Our results indicate that CA scaffolds have utility as a simple and inexpensive means to cultivate CSCs in vitro in support of studies to understand CSC biology and develop more effective anti-cancer therapies. Copyright © 2014 Elsevier Ltd. All rights reserved.

Formation of Neural Networks in 3D Scaffolds Fabricated by Means of Laser Microstereolithography.

Science.gov (United States)

Vedunova, M V; Timashev, P S; Mishchenko, T A; Mitroshina, E V; Koroleva, A V; Chichkov, B N; Panchenko, V Ya; Bagratashvili, V N; Mukhina, I V

2016-08-01

We developed and tested new 3D scaffolds for neurotransplantation. Scaffolds of predetermined architectonic were prepared using microstereolithography technique. Scaffolds were highly biocompatible with the nervous tissue cells. In vitro studies showed that the material of fabricated scaffolds is not toxic for dissociated brain cells and promotes the formation of functional neural networks in the matrix. These results demonstrate the possibility of fabrication of tissue-engineering constructs for neurotransplantation based on created scaffolds.

Scaffold-hopping from xanthines to tricyclic guanines: A case study of dipeptidyl peptidase 4 (DPP4) inhibitors

Energy Technology Data Exchange (ETDEWEB)

Pissarnitski, Dmitri A.; Zhao, Zhiqiang; Cole, David; Wu, Wen-Lian; Domalski, Martin; Clader, John W.; Scapin, Giovanna; Voigt, Johannes; Soriano, Aileen; Kelly, Theresa; Powles, Mary Ann; Yao, Zuliang; Burnett, Duane A. (Merck)

2016-11-01

Molecular modeling of unbound tricyclic guanine scaffolds indicated that they can serve as effective bioisosteric replacements of xanthines. This notion was further confirmed by a combination of X-ray crystallography and SAR studies, indicating that tricyclic guanine DPP4 inhibitors mimic the binding mode of xanthine inhibitors, exemplified by linagliptin. Realization of the bioisosteric relationship between these scaffolds potentially will lead to a wider application of cyclic guanines as xanthine replacements in drug discovery programs for a variety of biological targets. Newly designed DPP4 inhibitors achieved sub-nanomolar potency range and demonstrated oral activity in vivo in mouse glucose tolerance test.

A 3D Electroactive Polypyrrole-Collagen Fibrous Scaffold for Tissue Engineering

Directory of Open Access Journals (Sweden)

Kam W. Leong

2011-02-01

Full Text Available Fibers that can provide topographical, biochemical and electrical cues would be attractive for directing the differentiation of stem cells into electro-responsive cells such as neuronal or muscular cells. Here we report on the fabrication of polypyrrole-incorporated collagen-based fibers via interfacial polyelectrolyte complexation (IPC. The mean ultimate tensile strength of the fibers is 304.0 ± 61.0 MPa and the Young’s Modulus is 10.4 ± 4.3 GPa. Human bone marrow-derived mesenchymal stem cells (hMSCs are cultured on the fibers in a proliferating medium and stimulated with an external electrical pulse generator for 5 and 10 days. The effects of polypyrrole in the fiber system can be observed, with hMSCs adopting a neuronal-like morphology at day 10, and through the upregulation of neural markers, such as noggin, MAP2, neurofilament, β tubulin III and nestin. This study demonstrates the potential of this fiber system as an attractive 3D scaffold for tissue engineering, where collagen is present on the fiber surface for cellular adhesion, and polypyrrole is encapsulated within the fiber for enhanced electrical communication in cell-substrate and cell-cell interactions.

Strategies for neurotrophin-3 and chondroitinase ABC release from freeze-cast chitosan-alginate nerve-guidance scaffolds.

Science.gov (United States)

Francis, Nicola L; Hunger, Philipp M; Donius, Amalie E; Wegst, Ulrike G K; Wheatley, Margaret A

2017-01-01

Freeze casting, or controlled unidirectional solidification, can be used to fabricate chitosan-alginate (C-A) scaffolds with highly aligned porosity that are suitable for use as nerve-guidance channels. To augment the guidance of growth across a spinal cord injury lesion, these scaffolds are now evaluated in vitro to assess their ability to release neurotrophin-3 (NT-3) and chondroitinase ABC (chABC) in a controlled manner. Protein-loaded microcapsules were incorporated into C-A scaffolds prior to freeze casting without affecting the original scaffold architecture. In vitro protein release was not significantly different when comparing protein loaded directly into the scaffolds with release from scaffolds containing incorporated microcapsules. NT-3 was released from the C-A scaffolds for 8 weeks in vitro, while chABC was released for up to 7 weeks. Low total percentages of protein released from the scaffolds over this time period were attributed to limitation of diffusion by the interpenetrating polymer network matrix of the scaffold walls. NT-3 and chABC released from the scaffolds retained bioactivity, as determined by a neurite outgrowth assay, and the promotion of neurite growth across an inhibitory barrier of chondroitin sulphate proteoglycans. This demonstrates the potential of these multifunctional scaffolds for enhancing axonal regeneration through growth-inhibiting glial scars via the sustained release of chABC and NT-3. Copyright © 2014 John Wiley & Sons, Ltd. Copyright © 2014 John Wiley & Sons, Ltd.

Biomechanical properties of 3D-printed bone scaffolds are improved by treatment with CRFP.

Science.gov (United States)

Helguero, Carlos G; Mustahsan, Vamiq M; Parmar, Sunjit; Pentyala, Sahana; Pfail, John L; Kao, Imin; Komatsu, David E; Pentyala, Srinivas

2017-12-22

One of the major challenges in orthopedics is to develop implants that overcome current postoperative problems such as osteointegration, proper load bearing, and stress shielding. Current implant techniques such as allografts or endoprostheses never reach full bone integration, and the risk of fracture due to stress shielding is a major concern. To overcome this, a novel technique of reverse engineering to create artificial scaffolds was designed and tested. The purpose of the study is to create a new generation of implants that are both biocompatible and biomimetic. 3D-printed scaffolds based on physiological trabecular bone patterning were printed. MC3T3 cells were cultured on these scaffolds in osteogenic media, with and without the addition of Calcitonin Receptor Fragment Peptide (CRFP) in order to assess bone formation on the surfaces of the scaffolds. Integrity of these cell-seeded bone-coated scaffolds was tested for their mechanical strength. The results show that cellular proliferation and bone matrix formation are both supported by our 3D-printed scaffolds. The mechanical strength of the scaffolds was enhanced by trabecular patterning in the order of 20% for compression strength and 60% for compressive modulus. Furthermore, cell-seeded trabecular scaffolds modulus increased fourfold when treated with CRFP. Upon mineralization, the cell-seeded trabecular implants treated with osteo-inductive agents and pretreated with CRFP showed a significant increase in the compressive modulus. This work will lead to creating 3D structures that can be used in the replacement of not only bone segments, but entire bones.

The Use of Poly-4-Hydroxybutyrate (P4HB) Scaffold in the Ptotic Breast: A Multicenter Clinical Study.

Science.gov (United States)

Adams, William P; Baxter, Richard; Glicksman, Caroline; Mast, Bruce A; Tantillo, Michael; Van Natta, Bruce W

2018-04-06

Mastopexy and reduction mammaplasty are often limited by the patient's poor native soft tissue quality, resulting in ptosis recurrence and loss of rejuvenated surgical results. Surgical scaffolds and acellular dermal matrices are used in these procedures to provide physical and mechanical stabilization of weakened or compromised tissue. GalaFLEX scaffold, made from poly-4-hydroxybutyrate (P4HB), is a next-generation product for soft tissue reinforcement that resorbs gradually while aiding tissue regeneration to achieve excellent outcomes. To assess the clinical performance of GalaFLEX scaffold in soft tissue reinforcement during elective mastopexy and reduction mammaplasty. This multicenter, single-arm, observational study assessed product performance and outcomes of GalaFLEX scaffold when used in breast surgery. Outcomes included ptosis correction and maintenance, associated adverse events, patient and surgeon satisfaction, and mammographic and ultrasound imaging evaluation. At 6 centers in the US, 62 of 69 enrolled patients were treated. Of this population, 89.7% had successful ptosis correction and maintenance at 1 year, with high patient and surgeon satisfaction for breast shape, droop/sag of the breast, and maintenance of results at 1 year. There were 5 adverse events deemed related to the device (8.0%), including nerve pain, breast swelling, ptosis, and 2 instances of asymmetry. GalaFLEX scaffold safely and successfully supports and elevates breast tissue in mastopexy and reduction mammaplasty, with maintained support at 1 year. Surgeon and patient satisfaction were high. No mammogram or ultrasound interference was detected.

Fabrication and evaluation of 3D β-TCP scaffold by novel direct-write assembly method

International Nuclear Information System (INIS)

Sa, Min Woo; Kim, Jong Young

2015-01-01

Various scaffold fabrication methods have been explored to enhance the cell interaction effects and mechanical properties of scaffolds in bone regeneration. Rapid prototyping (RP) for tissue engineering is a useful technology that may provide a potential scaffolding structure to regenerate, restore, and repair a damaged bone tissue or organ, that is, RP is a promising tissue engineering technique through a 3D scaffold fabrication by using a computer-aided design/computer-aided manufacturing system. In this study, 3D β-tricalcium phosphate (β-TCP) scaffolds were fabricated by a novel direct-write assembly method. The mechanical property of β-TCP scaffolds was analyzed by stress-strain curves by using a compression testing machine. Furthermore, an in vitro CCK-8 assay of osteosarcoma MG-63 cells showed the significant cell attachment and proliferation in the β-TCP scaffold.

Fabrication and evaluation of 3D β-TCP scaffold by novel direct-write assembly method

Energy Technology Data Exchange (ETDEWEB)

Sa, Min Woo; Kim, Jong Young [Andong National University, Andong (Korea, Republic of)

2015-11-15

Various scaffold fabrication methods have been explored to enhance the cell interaction effects and mechanical properties of scaffolds in bone regeneration. Rapid prototyping (RP) for tissue engineering is a useful technology that may provide a potential scaffolding structure to regenerate, restore, and repair a damaged bone tissue or organ, that is, RP is a promising tissue engineering technique through a 3D scaffold fabrication by using a computer-aided design/computer-aided manufacturing system. In this study, 3D β-tricalcium phosphate (β-TCP) scaffolds were fabricated by a novel direct-write assembly method. The mechanical property of β-TCP scaffolds was analyzed by stress-strain curves by using a compression testing machine. Furthermore, an in vitro CCK-8 assay of osteosarcoma MG-63 cells showed the significant cell attachment and proliferation in the β-TCP scaffold.

Microporous polymeric 3D scaffolds templated by the layer-by-layer self-assembly.

Science.gov (United States)

Paulraj, Thomas; Feoktistova, Natalia; Velk, Natalia; Uhlig, Katja; Duschl, Claus; Volodkin, Dmitry

2014-08-01

Polymeric scaffolds serve as valuable supports for biological cells since they offer essential features for guiding cellular organization and tissue development. The main challenges for scaffold fabrication are i) to tune an internal structure and ii) to load bio-molecules such as growth factors and control their local concentration and distribution. Here, a new approach for the design of hollow polymeric scaffolds using porous CaCO3 particles (cores) as templates is presented. The cores packed into a microfluidic channel are coated with polymers employing the layer-by-layer (LbL) technique. Subsequent core elimination at mild conditions results in formation of the scaffold composed of interconnected hollow polymer microspheres. The size of the cores determines the feature dimensions and, as a consequence, governs cellular adhesion: for 3T3 fibroblasts an optimal microsphere size is 12 μm. By making use of the carrier properties of the porous CaCO3 cores, the microspheres are loaded with BSA as a model protein. The scaffolds developed here may also be well suited for the localized release of bio-molecules using external triggers such as IR-light. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Porous titanium scaffolds fabricated using a rapid prototyping and powder metallurgy technique.

Science.gov (United States)

Ryan, Garrett E; Pandit, Abhay S; Apatsidis, Dimitrios P

2008-09-01

One of the main issues in orthopaedic implant design is the fabrication of scaffolds that closely mimic the biomechanical properties of the surrounding bone. This research reports on a multi-stage rapid prototyping technique that was successfully developed to produce porous titanium scaffolds with fully interconnected pore networks and reproducible porosity and pore size. The scaffolds' porous characteristics were governed by a sacrificial wax template, fabricated using a commercial 3D-printer. Powder metallurgy processes were employed to generate the titanium scaffolds by filling around the wax template with titanium slurry. In the attempt to optimise the powder metallurgy technique, variations in slurry concentration, compaction pressure and sintering temperature were investigated. By altering the wax design template, pore sizes ranging from 200 to 400 microm were achieved. Scaffolds with porosities of 66.8 +/- 3.6% revealed compression strengths of 104.4+/-22.5 MPa in the axial direction and 23.5 +/- 9.6 MPa in the transverse direction demonstrating their anisotropic nature. Scaffold topography was characterised using scanning electron microscopy and microcomputed tomography. Three-dimensional reconstruction enabled the main architectural parameters such as pore size, interconnecting porosity, level of anisotropy and level of structural disorder to be determined. The titanium scaffolds were compared to their intended designs, as governed by their sacrificial wax templates. Although discrepancies in architectural parameters existed between the intended and the actual scaffolds, overall the results indicate that the porous titanium scaffolds have the properties to be potentially employed in orthopaedic applications.

3D-Printed ABS and PLA Scaffolds for Cartilage and Nucleus Pulposus Tissue Regeneration

Directory of Open Access Journals (Sweden)

Derek H. Rosenzweig

2015-07-01

Full Text Available Painful degeneration of soft tissues accounts for high socioeconomic costs. Tissue engineering aims to provide biomimetics recapitulating native tissues. Biocompatible thermoplastics for 3D printing can generate high-resolution structures resembling tissue extracellular matrix. Large-pore 3D-printed acrylonitrile butadiene styrene (ABS and polylactic acid (PLA scaffolds were compared for cell ingrowth, viability, and tissue generation. Primary articular chondrocytes and nucleus pulposus (NP cells were cultured on ABS and PLA scaffolds for three weeks. Both cell types proliferated well, showed high viability, and produced ample amounts of proteoglycan and collagen type II on both scaffolds. NP generated more matrix than chondrocytes; however, no difference was observed between scaffold types. Mechanical testing revealed sustained scaffold stability. This study demonstrates that chondrocytes and NP cells can proliferate on both ABS and PLA scaffolds printed with a simplistic, inexpensive desktop 3D printer. Moreover, NP cells produced more proteoglycan than chondrocytes, irrespective of thermoplastic type, indicating that cells maintain individual phenotype over the three-week culture period. Future scaffold designs covering larger pore sizes and better mimicking native tissue structure combined with more flexible or resorbable materials may provide implantable constructs with the proper structure, function, and cellularity necessary for potential cartilage and disc tissue repair in vivo.

3D-Printed ABS and PLA Scaffolds for Cartilage and Nucleus Pulposus Tissue Regeneration.

Science.gov (United States)

Rosenzweig, Derek H; Carelli, Eric; Steffen, Thomas; Jarzem, Peter; Haglund, Lisbet

2015-07-03

Painful degeneration of soft tissues accounts for high socioeconomic costs. Tissue engineering aims to provide biomimetics recapitulating native tissues. Biocompatible thermoplastics for 3D printing can generate high-resolution structures resembling tissue extracellular matrix. Large-pore 3D-printed acrylonitrile butadiene styrene (ABS) and polylactic acid (PLA) scaffolds were compared for cell ingrowth, viability, and tissue generation. Primary articular chondrocytes and nucleus pulposus (NP) cells were cultured on ABS and PLA scaffolds for three weeks. Both cell types proliferated well, showed high viability, and produced ample amounts of proteoglycan and collagen type II on both scaffolds. NP generated more matrix than chondrocytes; however, no difference was observed between scaffold types. Mechanical testing revealed sustained scaffold stability. This study demonstrates that chondrocytes and NP cells can proliferate on both ABS and PLA scaffolds printed with a simplistic, inexpensive desktop 3D printer. Moreover, NP cells produced more proteoglycan than chondrocytes, irrespective of thermoplastic type, indicating that cells maintain individual phenotype over the three-week culture period. Future scaffold designs covering larger pore sizes and better mimicking native tissue structure combined with more flexible or resorbable materials may provide implantable constructs with the proper structure, function, and cellularity necessary for potential cartilage and disc tissue repair in vivo.

Influence of crosslinking on the mechanical behavior of 3D printed alginate scaffolds: Experimental and numerical approaches.

Science.gov (United States)

Naghieh, Saman; Karamooz-Ravari, Mohammad Reza; Sarker, M D; Karki, Eva; Chen, Xiongbiao

2018-04-01

Tissue scaffolds fabricated by three-dimensional (3D) bioprinting are attracting considerable attention for tissue engineering applications. Because the mechanical properties of hydrogel scaffolds should match the damaged tissue, changing various parameters during 3D bioprinting has been studied to manipulate the mechanical behavior of the resulting scaffolds. Crosslinking scaffolds using a cation solution (such as CaCl 2 ) is also important for regulating the mechanical properties, but has not been well documented in the literature. Here, the effect of varied crosslinking agent volume and crosslinking time on the mechanical behavior of 3D bioplotted alginate scaffolds was evaluated using both experimental and numerical methods. Compression tests were used to measure the elastic modulus of each scaffold, then a finite element model was developed and a power model used to predict scaffold mechanical behavior. Results showed that crosslinking time and volume of crosslinker both play a decisive role in modulating the mechanical properties of 3D bioplotted scaffolds. Because mechanical properties of scaffolds can affect cell response, the findings of this study can be implemented to modulate the elastic modulus of scaffolds according to the intended application. Copyright © 2018 Elsevier Ltd. All rights reserved.

Graphene-containing PCL- coated Porous 13-93B3 Bioactive Glass Scaffolds for Bone Regeneration

Science.gov (United States)

Türk, Mert; Deliormanlı, Aylin M.

2018-04-01

Borate-based 13-93B3 bioactive glass scaffolds were coated with the graphene-containing poly-caprolactone (PCL) solution to prepare electrically conductive composites for biomedical applications. Results revealed that electrical conductivity of the scaffolds increased with increasing concentration of graphene nanoparticles. Significant difference was not observed in hydroxyapatite forming ability of the bare and the graphene-containing scaffolds immersed in simulated body fluid. In vitro cytotoxicity experiments (XTT tests) showed that pre-osteoblastic MC3T3-E1 cell viability percentages of the graphene- containing samples was higher than control group samples after 7 days of incubation. However, a decrease in cell viability rates was obtained after 14 days of incubation for samples coated with PCL containing graphene starting from 3 wt%. Additionally, results obtained in the live-dead assay were consistent with the results of XTT tests. A higher ALP activity was detected in cells cultured on the graphene-containing borate glass scaffolds than those on the bare PCL coated 13-93B3 scaffolds suggesting the presence of graphene nanopowders stimulated an early stage of osteoblastic differentiation. SEM analysis showed that MC3T3-E1 cells exhibited a flat appearance and spread out through the surface in all groups of scaffolds starting from 3 days of incubation.

Mesoporous bioactive glass nanolayer-functionalized 3D-printed scaffolds for accelerating osteogenesis and angiogenesis

Science.gov (United States)

Zhang, Yali; Xia, Lunguo; Zhai, Dong; Shi, Mengchao; Luo, Yongxiang; Feng, Chun; Fang, Bing; Yin, Jingbo; Chang, Jiang; Wu, Chengtie

2015-11-01

The hierarchical microstructure, surface and interface of biomaterials are important factors influencing their bioactivity. Porous bioceramic scaffolds have been widely used for bone tissue engineering by optimizing their chemical composition and large-pore structure. However, the surface and interface of struts in bioceramic scaffolds are often ignored. The aim of this study is to incorporate hierarchical pores and bioactive components into the bioceramic scaffolds by constructing nanopores and bioactive elements on the struts of scaffolds and further improve their bone-forming activity. Mesoporous bioactive glass (MBG) modified β-tricalcium phosphate (MBG-β-TCP) scaffolds with a hierarchical pore structure and a functional strut surface (~100 nm of MBG nanolayer) were successfully prepared via 3D printing and spin coating. The compressive strength and apatite-mineralization ability of MBG-β-TCP scaffolds were significantly enhanced as compared to β-TCP scaffolds without the MBG nanolayer. The attachment, viability, alkaline phosphatase (ALP) activity, osteogenic gene expression (Runx2, BMP2, OPN and Col I) and protein expression (OPN, Col I, VEGF, HIF-1α) of rabbit bone marrow stromal cells (rBMSCs) as well as the attachment, viability and angiogenic gene expression (VEGF and HIF-1α) of human umbilical vein endothelial cells (HUVECs) in MBG-β-TCP scaffolds were significantly upregulated compared with conventional bioactive glass (BG)-modified β-TCP (BG-β-TCP) and pure β-TCP scaffolds. Furthermore, MBG-β-TCP scaffolds significantly enhanced the formation of new bone in vivo as compared to BG-β-TCP and β-TCP scaffolds. The results suggest that application of the MBG nanolayer to modify 3D-printed bioceramic scaffolds offers a new strategy to construct hierarchically porous scaffolds with significantly improved physicochemical and biological properties, such as mechanical properties, osteogenesis, angiogenesis and protein expression for bone tissue

Functionalization of 3D scaffolds with protein-releasing biomaterials for intracellular delivery.

Science.gov (United States)

Seras-Franzoso, Joaquin; Steurer, Christoph; Roldán, Mònica; Vendrell, Meritxell; Vidaurre-Agut, Carla; Tarruella, Anna; Saldaña, Laura; Vilaboa, Nuria; Parera, Marc; Elizondo, Elisa; Ratera, Imma; Ventosa, Nora; Veciana, Jaume; Campillo-Fernández, Alberto J; García-Fruitós, Elena; Vázquez, Esther; Villaverde, Antonio

2013-10-10

Appropriate combinations of mechanical and biological stimuli are required to promote proper colonization of substrate materials in regenerative medicine. In this context, 3D scaffolds formed by compatible and biodegradable materials are under continuous development in an attempt to mimic the extracellular environment of mammalian cells. We have here explored how novel 3D porous scaffolds constructed by polylactic acid, polycaprolactone or chitosan can be decorated with bacterial inclusion bodies, submicron protein particles formed by releasable functional proteins. A simple dipping-based decoration method tested here specifically favors the penetration of the functional particles deeper than 300μm from the materials' surface. The functionalized surfaces support the intracellular delivery of biologically active proteins to up to more than 80% of the colonizing cells, a process that is slightly influenced by the chemical nature of the scaffold. The combination of 3D soft scaffolds and protein-based sustained release systems (Bioscaffolds) offers promise in the fabrication of bio-inspired hybrid matrices for multifactorial control of cell proliferation in tissue engineering under complex architectonic setting-ups. © 2013.

Impedance Spectroscopic Characterisation of Porosity in 3D Cell Culture Scaffolds with Different Channel Networks

DEFF Research Database (Denmark)

Canali, Chiara; Mohanty, Soumyaranjan; Heiskanen, Arto

2015-01-01

We present the application of electrochemical impedance spectroscopy (EIS) as a method for discriminating between different polydimethylsiloxane (PDMS) scaffolds for three-dimensional (3D) cell cultures. The validity of EIS characterisation for scaffolds having different degree of porosity...... serve as means of single-frequency measurements for fast scaffold characterization combined with in vitro monitoring of 3D cell cultures....

3D printing of novel osteochondral scaffolds with graded microstructure

Science.gov (United States)

Nowicki, Margaret A.; Castro, Nathan J.; Plesniak, Michael W.; Zhang, Lijie Grace

2016-10-01

Osteochondral tissue has a complex graded structure where biological, physiological, and mechanical properties vary significantly over the full thickness spanning from the subchondral bone region beneath the joint surface to the hyaline cartilage region at the joint surface. This presents a significant challenge for tissue-engineered structures addressing osteochondral defects. Fused deposition modeling (FDM) 3D bioprinters present a unique solution to this problem. The objective of this study is to use FDM-based 3D bioprinting and nanocrystalline hydroxyapatite for improved bone marrow human mesenchymal stem cell (hMSC) adhesion, growth, and osteochondral differentiation. FDM printing parameters can be tuned through computer aided design and computer numerical control software to manipulate scaffold geometries in ways that are beneficial to mechanical performance without hindering cellular behavior. Additionally, the ability to fine-tune 3D printed scaffolds increases further through our investment casting procedure which facilitates the inclusion of nanoparticles with biochemical factors to further elicit desired hMSC differentiation. For this study, FDM was used to print investment-casting molds innovatively designed with varied pore distribution over the full thickness of the scaffold. The mechanical and biological impacts of the varied pore distributions were compared and evaluated to determine the benefits of this physical manipulation. The results indicate that both mechanical properties and cell performance improve in the graded pore structures when compared to homogeneously distributed porous and non-porous structures. Differentiation results indicated successful osteogenic and chondrogenic manipulation in engineered scaffolds.

Improving effects of chitosan nanofiber scaffolds on osteoblast proliferation and maturation

Directory of Open Access Journals (Sweden)

Ho MH

2014-09-01

Full Text Available Ming-Hua Ho,1,2 Mei-Hsiu Liao,3 Yi-Ling Lin,2 Chien-Hao Lai,3 Pei-I Lin,3 Ruei-Ming Chen2–4 1Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei, Taiwan; 2Cell Physiology and Molecular Image Research Center and Department of Anesthesiology, Wan Fang Hospital, 3Graduate Institute of Medical Sciences, Taipei Medical University, Taipei, Taiwan; 4Anesthetics and Toxicology Research Center, Taipei Medical University Hospital, Taipei, Taiwan Abstract: Osteoblast maturation plays a key role in regulating osteogenesis. Electrospun nanofibrous products were reported to possess a high surface area and porosity. In this study, we developed chitosan nanofibers and examined the effects of nanofibrous scaffolds on osteoblast maturation and the possible mechanisms. Macro- and micro observations of the chitosan nanofibers revealed that these nanoproducts had a flat surface and well-distributed fibers with nanoscale diameters. Mouse osteoblasts were able to attach onto the chitosan nanofiber scaffolds, and the scaffolds degraded in a time-dependent manner. Analysis by scanning electron microscopy further showed mouse osteoblasts adhered onto the scaffolds along the nanofibers, and cell–cell communication was also detected. Mouse osteoblasts grew much better on chitosan nanofiber scaffolds than on chitosan films. In addition, human osteoblasts were able to adhere and grow on the chitosan nanofiber scaffolds. Interestingly, culturing human osteoblasts on chitosan nanofiber scaffolds time-dependently increased DNA replication and cell proliferation. In parallel, administration of human osteoblasts onto chitosan nanofibers significantly induced osteopontin, osteocalcin, and alkaline phosphatase (ALP messenger (mRNA expression. As to the mechanism, chitosan nanofibers triggered runt-related transcription factor 2 mRNA and protein syntheses. Consequently, results of ALP-, alizarin red-, and von Kossa-staining analyses

Extrusion-based 3D printing of poly(propylene fumarate) scaffolds with hydroxyapatite gradients

Science.gov (United States)

Trachtenberg, Jordan E.; Placone, Jesse K.; Smith, Brandon T.; Fisher, John P.; Mikos, Antonios G.

2017-01-01

The primary focus of this work is to present the current challenges of printing scaffolds with concentration gradients of nanoparticles with an aim to improve the processing of these scaffolds. Furthermore, we address how print fidelity is related to material composition and emphasize the importance of considering this relationship when developing complex scaffolds for bone implants. The ability to create complex tissues is becoming increasingly relevant in the tissue engineering community. For bone tissue engineering applications, this work demonstrates the ability to use extrusion-based printing techniques to control the spatial deposition of hydroxyapatite (HA) nanoparticles in a 3D composite scaffold. In doing so, we combined the benefits of synthetic, degradable polymers, such as poly(propylene fumarate) (PPF), with osteoconductive HA nanoparticles that provide robust compressive mechanical properties. Furthermore, the final 3D printed scaffolds consisted of well-defined layers with interconnected pores, two critical features for a successful bone implant. To demonstrate a controlled gradient of HA, thermogravimetric analysis was carried out to quantify HA on a per-layer basis. Moreover, we non-destructively evaluated the tendency of HA particles to aggregate within PPF using micro-computed tomography (µCT). This work provides insight for proper fabrication and characterization of composite scaffolds containing particle gradients and has broad applicability for future efforts in fabricating complex scaffolds for tissue engineering applications. PMID:28125380

Design of 3D scaffolds for tissue engineering testing a tough polylactide-based graft copolymer

International Nuclear Information System (INIS)

Dorati, R.; Colonna, C.; Tomasi, C.; Genta, I.; Bruni, G.; Conti, B.

2014-01-01

The aim of this research was to investigate a tough polymer to develop 3D scaffolds and 2D films for tissue engineering applications, in particular to repair urethral strictures or defects. The polymer tested was a graft copolymer of polylactic acid (PLA) synthesized with the rationale to improve the toughness of the related PLA homopolymer. The LMP-3055 graft copolymer (in bulk) demonstrated to have negligible cytotoxicity (bioavailability > 85%, MTT test). Moreover, the LMP-3055 sterilized through gamma rays resulted to be cytocompatible and non-toxic, and it has a positive effect on cell biofunctionality, promoting the cell growth. 3D scaffolds and 2D film were prepared using different LMP-3055 polymer concentrations (7.5, 10, 12.5 and 15%, w/v), and the effect of polymer concentration on pore size, porosity and interconnectivity of the 3D scaffolds and 2D film was investigated. 3D scaffolds got better results for fulfilling structural and biofunctional requirements: porosity, pore size and interconnectivity, cell attachment and proliferation. 3D scaffolds obtained with 10 and 12.5% polymer solutions (3D-2 and 3D-3, respectively) were identified as the most suitable construct for the cell attachment and proliferation presenting pore size ranged between 100 and 400 μm, high porosity (77–78%) and well interconnected pores. In vitro cell studies demonstrated that all the selected scaffolds were able to support the cell proliferation, the cell attachment and growth resulting to their dependency on the polymer concentration and structural features. The degradation test revealed that the degradation of polymer matrix (ΔMw) and water uptake of 3D scaffolds exceed those of 2D film and raw polymer (used as control reference), while the mass loss of samples (3D scaffold and 2D film) resulted to be controlled, they showed good stability and capacity to maintain the physical integrity during the incubation time. - Highlights: • Tough PLA graft copolymer was proposed

Design of 3D scaffolds for tissue engineering testing a tough polylactide-based graft copolymer

Energy Technology Data Exchange (ETDEWEB)

Dorati, R., E-mail: rossella.dorati@unipv.it [Department of Drug Sciences, University of Pavia, V.le Taramelli 12, 27100 Pavia (Italy); Center for Tissue Engineering (CIT), University of Pavia, Via Ferrata 1, 27100 Pavia (Italy); Colonna, C. [Department of Drug Sciences, University of Pavia, V.le Taramelli 12, 27100 Pavia (Italy); Center for Tissue Engineering (CIT), University of Pavia, Via Ferrata 1, 27100 Pavia (Italy); Tomasi, C. [C.S.G.I., Department of Chemistry, Division of Physical Chemistry, University of Pavia, V.le Taramelli 16 I, 27100 Pavia (Italy); Genta, I. [Department of Drug Sciences, University of Pavia, V.le Taramelli 12, 27100 Pavia (Italy); Center for Tissue Engineering (CIT), University of Pavia, Via Ferrata 1, 27100 Pavia (Italy); Bruni, G. [C.S.G.I., Department of Chemistry, Division of Physical Chemistry, University of Pavia, V.le Taramelli 16 I, 27100 Pavia (Italy); Conti, B. [Department of Drug Sciences, University of Pavia, V.le Taramelli 12, 27100 Pavia (Italy); Center for Tissue Engineering (CIT), University of Pavia, Via Ferrata 1, 27100 Pavia (Italy)

2014-01-01

The aim of this research was to investigate a tough polymer to develop 3D scaffolds and 2D films for tissue engineering applications, in particular to repair urethral strictures or defects. The polymer tested was a graft copolymer of polylactic acid (PLA) synthesized with the rationale to improve the toughness of the related PLA homopolymer. The LMP-3055 graft copolymer (in bulk) demonstrated to have negligible cytotoxicity (bioavailability > 85%, MTT test). Moreover, the LMP-3055 sterilized through gamma rays resulted to be cytocompatible and non-toxic, and it has a positive effect on cell biofunctionality, promoting the cell growth. 3D scaffolds and 2D film were prepared using different LMP-3055 polymer concentrations (7.5, 10, 12.5 and 15%, w/v), and the effect of polymer concentration on pore size, porosity and interconnectivity of the 3D scaffolds and 2D film was investigated. 3D scaffolds got better results for fulfilling structural and biofunctional requirements: porosity, pore size and interconnectivity, cell attachment and proliferation. 3D scaffolds obtained with 10 and 12.5% polymer solutions (3D-2 and 3D-3, respectively) were identified as the most suitable construct for the cell attachment and proliferation presenting pore size ranged between 100 and 400 μm, high porosity (77–78%) and well interconnected pores. In vitro cell studies demonstrated that all the selected scaffolds were able to support the cell proliferation, the cell attachment and growth resulting to their dependency on the polymer concentration and structural features. The degradation test revealed that the degradation of polymer matrix (ΔMw) and water uptake of 3D scaffolds exceed those of 2D film and raw polymer (used as control reference), while the mass loss of samples (3D scaffold and 2D film) resulted to be controlled, they showed good stability and capacity to maintain the physical integrity during the incubation time. - Highlights: • Tough PLA graft copolymer was proposed

Balancing mechanical strength with bioactivity in chitosan-calcium phosphate 3D microsphere scaffolds for bone tissue engineering: air- vs. freeze-drying processes.

Science.gov (United States)

Nguyen, D T; McCanless, J D; Mecwan, M M; Noblett, A P; Haggard, W O; Smith, R A; Bumgardner, J D

2013-01-01

The objective of this study was to evaluate the potential benefit of 3D composite scaffolds composed of chitosan and calcium phosphate for bone tissue engineering. Additionally, incorporation of mechanically weak lyophilized microspheres within those air-dried (AD) was considered for enhanced bioactivity. AD microsphere, alone, and air- and freeze-dried microsphere (FDAD) 3D scaffolds were evaluated in vitro using a 28-day osteogenic culture model with the Saos-2 cell line. Mechanical testing, quantitative microscopy, and lysozyme-driven enzymatic degradation of the scaffolds were also studied. FDAD scaffold showed a higher concentration (p < 0.01) in cells per scaffold mass vs. AD constructs. Collagen was ∼31% greater (p < 0.01) on FDAD compared to AD scaffolds not evident in microscopy of microsphere surfaces. Alternatively, AD scaffolds demonstrated a superior threefold increase in compressive strength over FDAD (12 vs. 4 MPa) with minimal degradation. Inclusion of FD spheres within the FDAD scaffolds allowed increased cellular activity through improved seeding, proliferation, and extracellular matrix production (as collagen), although mechanical strength was sacrificed through introduction of the less stiff, porous FD spheres.

Two-photon polymerization technique for microfabrication of CAD-designed 3D scaffolds from commercially available photosensitive materials.

Science.gov (United States)

Ovsianikov, Aleksandr; Schlie, Sabrina; Ngezahayo, Anaclet; Haverich, Axel; Chichkov, Boris N

2007-01-01

We report on recent advances in the fabrication of three-dimensional (3D) scaffolds for tissue engineering and regenerative medicine constructs using a two-photon polymerization technique (2PP). 2PP is a novel CAD/CAM technology allowing the fabrication of any computer-designed 3D structure from a photosensitive polymeric material. The flexibility of this technology and the ability to precisely define 3D construct geometry allows issues associated with vascularization and patient-specific tissue fabrication to be directly addressed. The fabrication of reproducible scaffold structures by 2PP is important for systematic studies of cellular processes and better understanding of in vitro tissue formation. In this study, 2PP was applied for the generation of 3D scaffold-like structures, using the photosensitive organic-inorganic hybrid polymer ORMOCER (ORganically MOdified CERamics) and epoxy-based SU8 materials. By comparing the proliferation rates of cells grown on flat material surfaces and under control conditions, it was demonstrated that ORMOCER and SU8 are not cytotoxic. Additional tests show that the DNA strand breaking of GFSHR-17 granulosa cells was not affected by the presence of ORMOCER. Furthermore, gap junction conductance measurements revealed that ORMOCER did not alter the formation of cell-cell junctions, critical for functional tissue growth. The possibilities of seeding 3D structures with cells were analysed. These studies demonstrate the great potential of 2PP technique for the manufacturing of scaffolds with controlled topology and properties.

Design of 3D scaffolds for tissue engineering testing a tough polylactide-based graft copolymer.

Science.gov (United States)

Dorati, R; Colonna, C; Tomasi, C; Genta, I; Bruni, G; Conti, B

2014-01-01

The aim of this research was to investigate a tough polymer to develop 3D scaffolds and 2D films for tissue engineering applications, in particular to repair urethral strictures or defects. The polymer tested was a graft copolymer of polylactic acid (PLA) synthesized with the rationale to improve the toughness of the related PLA homopolymer. The LMP-3055 graft copolymer (in bulk) demonstrated to have negligible cytotoxicity (bioavailability >85%, MTT test). Moreover, the LMP-3055 sterilized through gamma rays resulted to be cytocompatible and non-toxic, and it has a positive effect on cell biofunctionality, promoting the cell growth. 3D scaffolds and 2D film were prepared using different LMP-3055 polymer concentrations (7.5, 10, 12.5 and 15%, w/v), and the effect of polymer concentration on pore size, porosity and interconnectivity of the 3D scaffolds and 2D film was investigated. 3D scaffolds got better results for fulfilling structural and biofunctional requirements: porosity, pore size and interconnectivity, cell attachment and proliferation. 3D scaffolds obtained with 10 and 12.5% polymer solutions (3D-2 and 3D-3, respectively) were identified as the most suitable construct for the cell attachment and proliferation presenting pore size ranged between 100 and 400μm, high porosity (77-78%) and well interconnected pores. In vitro cell studies demonstrated that all the selected scaffolds were able to support the cell proliferation, the cell attachment and growth resulting to their dependency on the polymer concentration and structural features. The degradation test revealed that the degradation of polymer matrix (ΔMw) and water uptake of 3D scaffolds exceed those of 2D film and raw polymer (used as control reference), while the mass loss of samples (3D scaffold and 2D film) resulted to be controlled, they showed good stability and capacity to maintain the physical integrity during the incubation time. © 2013.

Chitosan-based hydrogel tissue scaffolds made by 3D plotting promotes osteoblast proliferation and mineralization.

Science.gov (United States)

Liu, I-Hsin; Chang, Shih-Hsin; Lin, Hsin-Yi

2015-05-13

A 3D plotting system was used to make chitosan-based tissue scaffolds with interconnected pores using pure chitosan (C) and chitosan cross-linked with pectin (CP) and genipin (CG). A freeze-dried chitosan scaffold (CF/D) was made to compare with C, to observe the effects of structural differences. The fiber size, pore size, porosity, compression strength, swelling ratio, drug release efficacy, and cumulative weight loss of the scaffolds were measured. Osteoblasts were cultured on the scaffolds and their proliferation, type I collagen production, alkaline phosphatase activity, calcium deposition, and morphology were observed. C had a lower swelling ratio, degradation, porosity and drug release efficacy and a higher compressional stiffness and cell proliferation compared to CF/D (p 3D-plotted samples, cells on CP exhibited the highest degree of mineralization after 21 d (p 3D-plotted scaffolds were stronger, less likely to degrade and better promoted osteoblast cell proliferation in vitro compared to the freeze-dried scaffolds. C, CP and CG were structurally similar, and the different crosslinking caused significant changes in their physical and biological performances.

Ovalbumin-BasedPorous Scaffolds for Bone Tissue Regeneration

Directory of Open Access Journals (Sweden)

Gabrielle Farrar

2010-01-01

Full Text Available Cell differentiation on glutaraldehyde cross-linked ovalbumin scaffolds was the main focus of this research. Salt leaching and freeze drying were used to create a three-dimensional porous structure. Average pore size was 147.84±40.36 μm and 111.79±30.71 μm for surface and cross sectional area, respectively. Wet compressive strength and elastic modulus were 6.8±3.6 kPa. Average glass transition temperature was 320.1±1.4°C. Scaffolds were sterilized with ethylene oxide prior to seeding MC3T3-E1 cells. Cells were stained with DAPI and Texas red to determine morphology and proliferation. Average cell numbers increased between 4-hour- and 96-hour-cultured scaffolds. Alkaline phosphatase and osteocalcin levels were measured at 3, 7, 14, and 21 days. Differentiation studies showed an increase in osteocalcin at 21 days and alkaline phosphatase levels at 14 days, both indicating differentiation occurred. This work demonstrated the use of ovalbumin scaffolds for a bone tissue engineering application.

Large 3D direct laser written scaffolds for tissue engineering applications

Science.gov (United States)

Trautmann, Anika; Rüth, Marieke; Lemke, Horst-Dieter; Walther, Thomas; Hellmann, Ralf

2018-01-01

We report on the fabrication of three-dimensional direct laser written scaffolds for tissue engineering and the seeding of primary fibroblasts on these structures. Scaffolds are realized by two-photon absorption induced polymerization in the inorganic-organic hybrid polymer OrmoComp using a 515 nm femtosecond laser. A nonstop single-line single-pass writing process is implemented in order to produce periodic reproducible large scaled structures with a dimension in the range of several millimeters and reduce process time to less than one hour. This method allows us to determine optimized process parameters for writing stable structures while achieving pore sizes ranging from 5 μm to 90 μm and a scanning speed of up to 5 mm/s. After a multi-stage post-treatment, normal human dermal fibroblasts are applied to the scaffolds to test if these macroscopic structures with large surface and numerous small gaps between the pores provide nontoxic conditions. Furthermore, we study the cell behavior in this environment and observe both cell growth on as well as ingrowth on the three-dimensional structures. In particular, fibroblasts adhere and grow also on the vertical walls of the scaffolds.

Ultrasound promoted one-pot synthesis of 2-amino-4,8-dihydropyrano[3,2-b]pyran-3-carbonitrile scaffolds in aqueous media: a complementary 'green chemistry' tool to organic synthesis.

Science.gov (United States)

Banitaba, Sayed Hossein; Safari, Javad; Khalili, Shiva Dehghan

2013-01-01

A green and simple approach to assembling of 2-amino-4,8-dihydropyrano[3,2-b]pyran-3-carbonitrile scaffolds via three-component reaction of kojic acid, malononitrile, and aromatic aldehydes in aqueous media under ultrasound irradiation is described. The combinatorial synthesis was achieved for this methodology with applying ultrasound irradiation while making use of water as green solvent. In comparison to conventional methods, experimental simplicity, good functional group tolerance, excellent yields, short routine, and selectivity without the need for a transition metal or base catalyst are prominent features of this green procedure. Copyright © 2012 Elsevier B.V. All rights reserved.

Antimicrobial 3D Porous Scaffolds Prepared by Additive Manufacturing and Breath Figures.

Science.gov (United States)

Vargas-Alfredo, Nelson; Dorronsoro, Ane; Cortajarena, Aitziber L; Rodríguez-Hernández, Juan

2017-10-25

We describe herein a novel strategy for the fabrication of efficient 3D printed antibacterial scaffolds. For this purpose, both the surface topography as well as the chemical composition of 3D scaffolds fabricated by additive manufacturing were modified. The scaffolds were fabricated by fused deposition modeling (FDM) using high-impact polystyrene (HIPS) filaments. The surface of the objects was then topographically modified providing materials with porous surfaces by means of the Breath Figures approach. The strategy involves the immersion of the scaffold in a polymer solution during a precise period of time. This approach permitted the modification of the pore size varying the immersion time as well as the solution concentration. Moreover, by using polymer blend solutions of polystyrene and polystyrene-b-poly(acrylic acid) (PS 23 -b-PAA 18 ) and a quaternized polystyrene-b-poly(dimethylaminoethyl methacrylate) (PS 42 -b-PDMAEMAQ 17 ), the scaffolds were simultaneously chemically modified. The surfaces were characterized by scanning electron microscopy and infrared spectroscopy. Finally, the biological response toward bacteria was explored. Porous surfaces prepared using quaternized PDMAEMA as well as those prepared using PAA confer antimicrobial activity to the films, i.e., were able to kill on contact Staphylococcus aureus employed as model bacteria.

Bioactive glass-poly (ε-caprolactone) composite scaffolds with 3 dimensionally hierarchical pore networks

International Nuclear Information System (INIS)

Yun, Hui-suk; Kim, Seung-eon; Park, Eui Kyun

2011-01-01

Hierarchically mesoporous-macroporous-giant-porous bioactive glass/poly ε-caprolactone (PCL) composite scaffolds were prepared using a combination of the sol-gel method, evaporation-induced self-assembly process in the presence of nonionic triblock copolymer, EO 100 PO 65 EO 100 (F127), as template, salt leaching method, and rapid prototyping techniques. F127 acts as a template, inducing the formation of mesopores, NaCl with sizes between 25 and 33 μm provides macro-pores after leaching, and rapid prototyping produces giant-pores. The structure and morphology of the scaffolds were characterized by the field emission scanning electron microscopy, transmission electron microscopy, and Hg porosimetry. The mechanical properties of the scaffolds were examined by the dynamic mechanical analysis. Their in vitro bioactivities were confirmed by immersing the scaffolds in simulated body fluid. Their biocompatibilities were also evaluated by culturing human bone marrow stromal cells on the scaffolds. The scaffolds show good molding capabilities, mechanical properties, 3 dimensionally well-interconnected pore structures, bioactivities, and biocompatibilities in vitro. Depending on the amount of NaCl, the scaffolds also show unique sponge-like properties, but still retain better mechanical properties than general salt leaching derived PCL scaffolds. All of the data provide good evidence that the obtained scaffolds possess excellent potential for applications in the fields of tissue engineering and drug storage.

Enhancement of neurite outgrowth in neuron cancer stem cells by growth on 3-D collagen scaffolds

Energy Technology Data Exchange (ETDEWEB)

Chen, Chih-Hao [Department of Electrical Engineering, I-Shou University, Taiwan, ROC (China); Neurosurgery, Department of Surgery, Kaohsiung Veterans General Hospital, Taiwan, ROC (China); Department of Biomedical Engineering, I-Shou University, Taiwan, ROC (China); Kuo, Shyh Ming [Department of Biomedical Engineering, I-Shou University, Taiwan, ROC (China); Liu, Guei-Sheung [Centre for Eye Research Australia, University of Melbourne (Australia); Chen, Wan-Nan U. [Department of Biological Science and Technology, I-Shou University, Taiwan, ROC (China); Chuang, Chin-Wen [Department of Electrical Engineering, I-Shou University, Taiwan, ROC (China); Liu, Li-Feng, E-mail: liulf@isu.edu.tw [Department of Biological Science and Technology, I-Shou University, Taiwan, ROC (China)

2012-11-09

Highlights: Black-Right-Pointing-Pointer Neuron cancer stem cells (NCSCs) behave high multiply of growth on collagen scaffold. Black-Right-Pointing-Pointer Enhancement of NCSCs neurite outgrowth on porous collagen scaffold. Black-Right-Pointing-Pointer 3-D collagen culture of NCSCs shows an advance differentiation than 2-D culture. -- Abstract: Collagen is one component of the extracellular matrix that has been widely used for constructive remodeling to facilitate cell growth and differentiation. The 3-D distribution and growth of cells within the porous scaffold suggest a clinical significance for nerve tissue engineering. In the current study, we investigated proliferation and differentiation of neuron cancer stem cells (NCSCs) on a 3-D porous collagen scaffold that mimics the natural extracellular matrix. We first generated green fluorescence protein (GFP) expressing NCSCs using a lentiviral system to instantly monitor the transitions of morphological changes during growth on the 3-D scaffold. We found that proliferation of GFP-NCSCs increased, and a single cell mass rapidly grew with unrestricted expansion between days 3 and 9 in culture. Moreover, immunostaining with neuronal nuclei (NeuN) revealed that NCSCs grown on the 3-D collagen scaffold significantly enhanced neurite outgrowth. Our findings confirmed that the 80 {mu}m porous collagen scaffold could enhance attachment, viability and differentiation of the cancer neural stem cells. This result could provide a new application for nerve tissue engineering and nerve regeneration.

Enhancement of neurite outgrowth in neuron cancer stem cells by growth on 3-D collagen scaffolds

International Nuclear Information System (INIS)

Chen, Chih-Hao; Kuo, Shyh Ming; Liu, Guei-Sheung; Chen, Wan-Nan U.; Chuang, Chin-Wen; Liu, Li-Feng

2012-01-01

Highlights: ► Neuron cancer stem cells (NCSCs) behave high multiply of growth on collagen scaffold. ► Enhancement of NCSCs neurite outgrowth on porous collagen scaffold. ► 3-D collagen culture of NCSCs shows an advance differentiation than 2-D culture. -- Abstract: Collagen is one component of the extracellular matrix that has been widely used for constructive remodeling to facilitate cell growth and differentiation. The 3-D distribution and growth of cells within the porous scaffold suggest a clinical significance for nerve tissue engineering. In the current study, we investigated proliferation and differentiation of neuron cancer stem cells (NCSCs) on a 3-D porous collagen scaffold that mimics the natural extracellular matrix. We first generated green fluorescence protein (GFP) expressing NCSCs using a lentiviral system to instantly monitor the transitions of morphological changes during growth on the 3-D scaffold. We found that proliferation of GFP-NCSCs increased, and a single cell mass rapidly grew with unrestricted expansion between days 3 and 9 in culture. Moreover, immunostaining with neuronal nuclei (NeuN) revealed that NCSCs grown on the 3-D collagen scaffold significantly enhanced neurite outgrowth. Our findings confirmed that the 80 μm porous collagen scaffold could enhance attachment, viability and differentiation of the cancer neural stem cells. This result could provide a new application for nerve tissue engineering and nerve regeneration.

Clinical Application of Scaffolds for Partial Meniscus Replacement.

Science.gov (United States)

Moran, Cathal J; Withers, Daniel P; Kurzweil, Peter R; Verdonk, Peter C

2015-09-01

Meniscal tears are common injuries often treated by partial meniscectomy. This may result in altered joint contact mechanics which in turn may lead to worsening symptoms and an increased risk of osteoarthritis. Meniscal scaffolds have been proposed as a treatment option aimed at reducing symptoms while also potentially reducing progression of degenerative change. There are 2 scaffolds available for clinical use at the present time; Collagen Meniscus Implant and Actifit. Medium-term to long-term data (4.9 to 11.3 y) demonstrate efficacy of partial meniscus replacement. The patients who seem to benefit most are chronic postmeniscectomy rather than acute meniscal injuries. Herein we report on available clinical data for Collagen Meniscus Implant and Actifit while describing our preferred surgical technique and postoperative rehabilitation program.

Scaffold Hopping Toward Agomelatine: Novel 3, 4-Dihydroisoquinoline Compounds as Potential Antidepressant Agents

Science.gov (United States)

Yang, Yang; Ang, Wei; Long, Haiyue; Chang, Ying; Li, Zicheng; Zhou, Liangxue; Yang, Tao; Deng, Yong; Luo, Youfu

2016-10-01

A scaffold-hopping strategy toward Agomelatine based on in silico screening and knowledge analysis was employed to design novel antidepressant agents. A series of 3, 4-dihydroisoquinoline compounds were selected for chemical synthesis and biological assessment. Three compounds (6a-1, 6a-2, 6a-9) demonstrated protective effects on corticosterone-induced lesion of PC12 cells. Compound 6a-1 also displayed low inhibitory effects on the growth of HEK293 and L02 normal cells and it was further evaluated for its potential antidepressant effects in vivo. The forced swim test (FST) results revealed that compound 6a-1 remarkably reduced the immobility time of rats and the open field test (OFT) results indicated a better general locomotor activity of the rats treated with compound 6a-1 than those with Agomelatine or Fluoxetine. Mechanism studies implied that compound 6a-1 can significantly reduce PC12 cell apoptosis by up-regulation of GSH and down-regulation of ROS in corticosterone-induced lesion of PC12 cells. Meanwhile, the down-regulation of calcium ion concentration and up-regulation of BDNF level in PC12 cells may account for the neuroprotective effects. Furthermore, compound 6a-1 can increase cell survival and cell proliferation, promote cell maturation in the rat hippocampus after chronic treatment. The acute toxicity data in vivo indicated compound 6a-1 exhibited less hepatotoxicity than Agomelatine.

Immunological compatibility status of placenta-derived stem cells is mediated by scaffold 3D structure.

Science.gov (United States)

Azizian, Sara; Khatami, Fatemeh; Modaresifar, Khashayar; Mosaffa, Nariman; Peirovi, Habibollah; Tayebi, Lobat; Bahrami, Soheyl; Redl, Heinz; Niknejad, Hassan

2018-02-23

Placenta-derived amniotic epithelial cells (AECs), a great cell source for tissue engineering and stem cell therapy, are immunologically inert in their native state; however, immunological changes in these cells after culture and differentiation have challenged their applications. The aim of this study was to investigate the effect of 2D and 3D scaffolds on human lymphocyte antigens (HLA) expression by AECs. The effect of different preparation parameters including pre-freezing time and temperature was evaluated on 3D chitosan-gelatine scaffolds properties. Evaluation of MHC class I, HLA-DR and HLA-G expression in AECs after 7 d culture on 2D bed and 3D scaffold of chitosan-gelatine showed that culture of AECs on the 2D substrate up-regulated MHC class I and HLA-DR protein markers on AECs surface and down-regulated HLA-G protein. In contrast, 3D scaffold did not increase protein expression of MHC class I and HLA-DR. Moreover, HLA-G protein expression remained unchanged in 3D culture. These results confirm that 3D scaffold can remain AECs in their native immunological state and modification of physical properties of the scaffold is a key regulator of immunological markers at the gene and protein expression levels; a strategy which circumvents rejection challenge of amniotic stem cells to be translated into the clinic.

3D printed porous polycaprolactone/oyster shell powder (PCL/OSP) scaffolds for bone tissue engineering

Science.gov (United States)

Luo, Wenfeng; Zhang, Shuangying; Lan, Yuewei; Huang, Chen; Wang, Chao; Lai, Xuexu; Chen, Hanwei; Ao, Ningjian

2018-04-01

In this work, oyster shell powder (OSP) was used as the bio-filler and combined with polycaprolactone (PCL) through melt blending methodology. The PCL and PCL/OSP scaffolds were prepared using additive manufacturing process. All the 3D printed scaffolds hold a highly porosity and interconnected pore structures. OSP particles are dispersed in the polymer matrix, which helped to improve the degree of crystallinity and mineralization ability of the scaffolds. There was no significant cytotoxicity of the prepared scaffolds towards MG-63 cells, and all the scaffolds showed a well ALP activity. Therefore, PCL/OSP scaffolds had a high potential to be employed in the bone tissue engineering.

Customized biomimetic scaffolds created by indirect three-dimensional printing for tissue engineering

International Nuclear Information System (INIS)

Lee, Ju-Yeon; Choi, Bogyu; Wu, Benjamin; Lee, Min

2013-01-01

Three-dimensional printing (3DP) is a rapid prototyping technique that can create complex 3D structures by inkjet printing of a liquid binder onto powder biomaterials for tissue engineering scaffolds. Direct fabrication of scaffolds from 3DP, however, imposes a limitation on material choices by manufacturing processes. In this study, we report an indirect 3DP approach wherein a positive replica of desired shapes was printed using gelatin particles, and the final scaffold was directly produced from the printed mold. To create patient-specific scaffolds that match precisely to a patient's external contours, we integrated our indirect 3DP technique with imaging technologies and successfully created custom scaffolds mimicking human mandibular condyle using polycaprolactone and chitosan for potential osteochondral tissue engineering. To test the ability of the technique to precisely control the internal morphology of the scaffolds, we created orthogonal interconnected channels within the scaffolds using computer-aided-design models. Because very few biomaterials are truly osteoinductive, we modified inert 3D printed materials with bioactive apatite coating. The feasibility of these scaffolds to support cell growth was investigated using bone marrow stromal cells (BMSC). The BMSCs showed good viability in the scaffolds, and the apatite coating further enhanced cellular spreading and proliferation. This technique may be valuable for complex scaffold fabrication. (paper)

High-efficiency pyrene-based blue light emitting diodes: Aggregation suppression using a calixarene 3D-scaffold

KAUST Repository

Chan, Khaileok

2012-01-01

An efficient blue light emitting diode based on solution processable pyrene-1,3-alt-calix[4]arene is demonstrated, providing a record current efficiency of 10.5 cd A -1 in a simple non-doped OLED configuration. Complete suppression of pyrene aggregation in the solid state is achieved by controlling chromophore dispersion using the 1,3-alt-calix[4]arene scaffold. © 2012 The Royal Society of Chemistry.

Laser Fabrication of 3D Gelatin Scaffolds for the Generation of Bioartificial Tissues

Directory of Open Access Journals (Sweden)

Mathias Wilhelmi

2011-01-01

Full Text Available In the present work, the two-photon polymerization (2PP technique was applied to develop precisely defined biodegradable 3D tissue engineering scaffolds. The scaffolds were fabricated via photopolymerization of gelatin modified with methacrylamide moieties. The results indicate that the gelatin derivative (GelMod preserves its enzymatic degradation capability after photopolymerization. In addition, the developed scaffolds using 2PP support primary adipose-derived stem cell (ASC adhesion, proliferation and differentiation into the anticipated lineage.

3D printing of porous hydroxyapatite scaffolds intended for use in bone tissue engineering applications

Energy Technology Data Exchange (ETDEWEB)

Cox, Sophie C.; Thornby, John A.; Gibbons, Gregory J., E-mail: G.J.Gibbons@warwick.ac.uk; Williams, Mark A.; Mallick, Kajal K.

2015-02-01

A systematic characterisation of bone tissue scaffolds fabricated via 3D printing from hydroxyapatite (HA) and poly(vinyl)alcohol (PVOH) composite powders is presented. Flowability of HA:PVOH precursor materials was observed to affect mechanical stability, microstructure and porosity of 3D printed scaffolds. Anisotropic behaviour of constructs and part failure at the boundaries of interlayer bonds was highlighted by compressive strength testing. A trade-off between the ability to facilitate removal of PVOH thermal degradation products during sintering and the compressive strength of green parts was revealed. The ultimate compressive strength of 55% porous green scaffolds printed along the Y-axis and dried in a vacuum oven for 6 h was 0.88 ± 0.02 MPa. Critically, the pores of 3D printed constructs could be user designed, ensuring bulk interconnectivity, and the imperfect packing of powder particles created an inherent surface roughness and non-designed porosity within the scaffold. These features are considered promising since they are known to facilitate osteoconduction and osteointegration in-vivo. Characterisation techniques utilised in this study include two funnel flow tests, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), compressive strength testing and computed tomography (CT). - Highlights: • Flowability of HA and PVOH powders corresponded to scaffold printability. • Anisotropic behaviour of 3D printed scaffolds was highlighted by compressive tests. • Maximum compressive strength of 3D printed 55% porous scaffolds was 0.88 MPa. • Imperfect packing of precursors resulted in a rough surface and microporosity. • A CT method was designed and used to quantify designed and non-designed porosity.

3D printing of porous hydroxyapatite scaffolds intended for use in bone tissue engineering applications

International Nuclear Information System (INIS)

Cox, Sophie C.; Thornby, John A.; Gibbons, Gregory J.; Williams, Mark A.; Mallick, Kajal K.

2015-01-01

A systematic characterisation of bone tissue scaffolds fabricated via 3D printing from hydroxyapatite (HA) and poly(vinyl)alcohol (PVOH) composite powders is presented. Flowability of HA:PVOH precursor materials was observed to affect mechanical stability, microstructure and porosity of 3D printed scaffolds. Anisotropic behaviour of constructs and part failure at the boundaries of interlayer bonds was highlighted by compressive strength testing. A trade-off between the ability to facilitate removal of PVOH thermal degradation products during sintering and the compressive strength of green parts was revealed. The ultimate compressive strength of 55% porous green scaffolds printed along the Y-axis and dried in a vacuum oven for 6 h was 0.88 ± 0.02 MPa. Critically, the pores of 3D printed constructs could be user designed, ensuring bulk interconnectivity, and the imperfect packing of powder particles created an inherent surface roughness and non-designed porosity within the scaffold. These features are considered promising since they are known to facilitate osteoconduction and osteointegration in-vivo. Characterisation techniques utilised in this study include two funnel flow tests, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), compressive strength testing and computed tomography (CT). - Highlights: • Flowability of HA and PVOH powders corresponded to scaffold printability. • Anisotropic behaviour of 3D printed scaffolds was highlighted by compressive tests. • Maximum compressive strength of 3D printed 55% porous scaffolds was 0.88 MPa. • Imperfect packing of precursors resulted in a rough surface and microporosity. • A CT method was designed and used to quantify designed and non-designed porosity

The effect of porosity on cell ingrowth into accurately defined, laser-made, polylactide-based 3D scaffolds

Energy Technology Data Exchange (ETDEWEB)

Danilevicius, Paulius; Georgiadi, Leoni [Foundation for Research and Technology Hellas (FORTH), Institute of Electronic Structure and Laser (IESL), N Plastira 100, 70013 Heraklion (Greece); Pateman, Christopher J.; Claeyssens, Frederik [Kroto Research Institute, Department of Materials Science and Engineering, University of Sheffield, Broad Lane, Sheffield S3 7HQ (United Kingdom); Chatzinikolaidou, Maria, E-mail: mchatzin@materials.uoc.gr [Foundation for Research and Technology Hellas (FORTH), Institute of Electronic Structure and Laser (IESL), N Plastira 100, 70013 Heraklion (Greece); Department of Materials Science and Technology, University of Crete, PO Box 2208, 71303 Heraklion (Greece); Farsari, Maria, E-mail: mfarsari@iesl.forth.gr [Foundation for Research and Technology Hellas (FORTH), Institute of Electronic Structure and Laser (IESL), N Plastira 100, 70013 Heraklion (Greece)

2015-05-01

Highlights: • We studied the porosity of laser-made 3D scaffolds on MC3T3-E1 pre-osteoblastic cells. • We made polylactide 3D scaffolds with pores 25–110 μm. - Abstract: The aim of this study is to demonstrate the accuracy required for the investigation of the role of solid scaffolds’ porosity in cell proliferation. We therefore present a qualitative investigation into the effect of porosity on MC3T3-E1 pre-osteoblastic cell ingrowth of three-dimensional (3D) scaffolds fabricated by direct femtosecond laser writing. The material we used is a purpose made photosensitive pre-polymer based on polylactide. We designed and fabricated complex, geometry-controlled 3D scaffolds with pore sizes ranging from 25 to 110 μm, representing porosities 70%, 82%, 86%, and 90%. The 70% porosity scaffolds did not support cell growth initially and in the long term. For the other porosities, we found a strong adhesion of the pre-osteoblastic cells from the first hours after seeding and a remarkable proliferation increase after 3 weeks and up to 8 weeks. The 86% porosity scaffolds exhibited a higher efficiency compared to 82% and 90%. In addition, bulk material degradation studies showed that the employed, highly-acrylated polylactide is degradable. These findings support the potential use of the proposed material and the scaffold fabrication technique in bone tissue engineering.

Fabrication of a Highly Aligned Neural Scaffold via a Table Top Stereolithography 3D Printing and Electrospinning.

Science.gov (United States)

Lee, Se-Jun; Nowicki, Margaret; Harris, Brent; Zhang, Lijie Grace

2017-06-01

Three-dimensional (3D) bioprinting is a rapidly emerging technique in the field of tissue engineering to fabricate extremely intricate and complex biomimetic scaffolds in the range of micrometers. Such customized 3D printed constructs can be used for the regeneration of complex tissues such as cartilage, vessels, and nerves. However, the 3D printing techniques often offer limited control over the resolution and compromised mechanical properties due to short selection of printable inks. To address these limitations, we combined stereolithography and electrospinning techniques to fabricate a novel 3D biomimetic neural scaffold with a tunable porous structure and embedded aligned fibers. By employing two different types of biofabrication methods, we successfully utilized both synthetic and natural materials with varying chemical composition as bioink to enhance biocompatibilities and mechanical properties of the scaffold. The resulting microfibers composed of polycaprolactone (PCL) polymer and PCL mixed with gelatin were embedded in 3D printed hydrogel scaffold. Our results showed that 3D printed scaffolds with electrospun fibers significantly improve neural stem cell adhesion when compared to those without the fibers. Furthermore, 3D scaffolds embedded with aligned fibers showed an enhancement in cell proliferation relative to bare control scaffolds. More importantly, confocal microscopy images illustrated that the scaffold with PCL/gelatin fibers greatly increased the average neurite length and directed neurite extension of primary cortical neurons along the fiber. The results of this study demonstrate the potential to create unique 3D neural tissue constructs by combining 3D bioprinting and electrospinning techniques.

Fabrication of Nanostructured Poly-ε-caprolactone 3D Scaffolds for 3D Cell Culture Technology

KAUST Repository

Schipani, Rossana

2015-04-21

Tissue engineering is receiving tremendous attention due to the necessity to overcome the limitations related to injured or diseased tissues or organs. It is the perfect combination of cells and biomimetic-engineered materials. With the appropriate biochemical factors, it is possible to develop new effective bio-devices that are capable to improve or replace biological functions. Latest developments in microfabrication methods, employing mostly synthetic biomaterials, allow the production of three-dimensional (3D) scaffolds that are able to direct cell-to-cell interactions and specific cellular functions in order to drive tissue regeneration or cell transplantation. The presented work offers a rapid and efficient method of 3D scaffolds fabrication by using optical lithography and micro-molding techniques. Bioresorbable polymer poly-ε-caprolactone (PCL) was the material used thanks to its high biocompatibility and ability to naturally degrade in tissues. 3D PCL substrates show a particular combination in the designed length scale: cylindrical shaped pillars with 10μm diameter, 10μm height, arranged in a hexagonal lattice with spacing of 20μm were obtained. The sidewalls of the pillars were nanostructured by attributing a 3D architecture to the scaffold. The suitability of these devices as cell culture technology supports was evaluated by plating NIH/3T3 mouse embryonic fibroblasts and human Neural Stem Cells (hNSC) on them. Scanning Electron Microscopy (SEM) analysis was carried out in order to examine the micro- and nano-patterns on the surface of the supports. In addition, after seeding of cells, SEM and immunofluorescence characterization of the fabricated systems were performed to check adhesion, growth and proliferation. It was observed that cells grow and develop healthy on the bio-polymeric devices by giving rise to well-interconnected networks. 3D PCL nano-patterned pillared scaffold therefore may have considerable potential as effective tool for

Application of quality by design for 3D printed bone prostheses and scaffolds.

Science.gov (United States)

Martinez-Marquez, Daniel; Mirnajafizadeh, Ali; Carty, Christopher P; Stewart, Rodney A

2018-01-01

3D printing is an emergent manufacturing technology recently being applied in the medical field for the development of custom bone prostheses and scaffolds. However, successful industry transformation to this new design and manufacturing approach requires technology integration, concurrent multi-disciplinary collaboration, and a robust quality management framework. This latter change enabler is the focus of this study. While a number of comprehensive quality frameworks have been developed in recent decades to ensure that the manufacturing of medical devices produces reliable products, they are centred on the traditional context of standardised manufacturing techniques. The advent of 3D printing technologies and the prospects for mass customisation provides significant market opportunities, but also presents a serious challenge to regulatory bodies tasked with managing and assuring product quality and safety. Before 3D printing bone prostheses and scaffolds can gain traction, industry stakeholders, such as regulators, clients, medical practitioners, insurers, lawyers, and manufacturers, would all require a high degree of confidence that customised manufacturing can achieve the same quality outcomes as standardised manufacturing. A Quality by Design (QbD) approach to custom 3D printed prostheses can help to ensure that products are designed and manufactured correctly from the beginning without errors. This paper reports on the adaptation of the QbD approach for the development process of 3D printed custom bone prosthesis and scaffolds. This was achieved through the identification of the Critical Quality Attributes of such products, and an extensive review of different design and fabrication methods for 3D printed bone prostheses. Research outcomes include the development of a comprehensive design and fabrication process flow diagram, and categorised risks associated with the design and fabrication processes of such products. An extensive systematic literature review

Application of quality by design for 3D printed bone prostheses and scaffolds

Science.gov (United States)

Martinez-Marquez, Daniel; Mirnajafizadeh, Ali; Carty, Christopher P.

2018-01-01

3D printing is an emergent manufacturing technology recently being applied in the medical field for the development of custom bone prostheses and scaffolds. However, successful industry transformation to this new design and manufacturing approach requires technology integration, concurrent multi-disciplinary collaboration, and a robust quality management framework. This latter change enabler is the focus of this study. While a number of comprehensive quality frameworks have been developed in recent decades to ensure that the manufacturing of medical devices produces reliable products, they are centred on the traditional context of standardised manufacturing techniques. The advent of 3D printing technologies and the prospects for mass customisation provides significant market opportunities, but also presents a serious challenge to regulatory bodies tasked with managing and assuring product quality and safety. Before 3D printing bone prostheses and scaffolds can gain traction, industry stakeholders, such as regulators, clients, medical practitioners, insurers, lawyers, and manufacturers, would all require a high degree of confidence that customised manufacturing can achieve the same quality outcomes as standardised manufacturing. A Quality by Design (QbD) approach to custom 3D printed prostheses can help to ensure that products are designed and manufactured correctly from the beginning without errors. This paper reports on the adaptation of the QbD approach for the development process of 3D printed custom bone prosthesis and scaffolds. This was achieved through the identification of the Critical Quality Attributes of such products, and an extensive review of different design and fabrication methods for 3D printed bone prostheses. Research outcomes include the development of a comprehensive design and fabrication process flow diagram, and categorised risks associated with the design and fabrication processes of such products. An extensive systematic literature review

Initial boost release of transforming growth factor-β3 and chondrogenesis by freeze-dried bioactive polymer scaffolds.

Science.gov (United States)

Krüger, Jan Philipp; Machens, Isabel; Lahner, Matthias; Endres, Michaela; Kaps, Christian

2014-12-01

In cartilage regeneration, bio-activated implants are used in stem and progenitor cell-based microfracture cartilage repair procedures. Our aim was to analyze the chondrogenic potential of freeze-dried resorbable polymer-based polyglycolic acid (PGA) scaffolds bio-activated with transforming growth factor-β3 (TGFB3) on human subchondral mesenchymal progenitor cells known from microfracture. Progenitor cells derived from femur heads were cultured in the presence of freeze-dried TGFB3 in high-density pellet culture and in freeze-dried TGFB3-PGA scaffolds for chondrogenic differentiation. Progenitor cell cultures in PGA scaffolds as well as pellet cultures with and without continuous application of TGFB3 served as controls. Release studies showed that freeze-dried TGFB3-PGA scaffolds facilitate a rapid, initial boost-like release of 71.5% of TGFB3 in the first 10 h. Gene expression analysis and histology showed induction of typical chondrogenic markers like type II collagen and formation of cartilaginous tissue in TGFB3-PGA scaffolds seeded with subchondral progenitor cells and in pellet cultures stimulated with freeze-dried TGFB3. Chondrogenic differentiation in freeze-dried TGFB3-PGA scaffolds was comparable to cultures receiving TGFB3 continuously, while non-stimulated controls did not show chondrogenesis during prolonged culture for 14 days. These results suggest that bio-activated, freeze-dried TGFB3-PGA scaffolds have chondrogenic potential and are a promising tool for stem cell-mediated cartilage regeneration.

Automated quality characterization of 3D printed bone scaffolds

Directory of Open Access Journals (Sweden)

Tzu-Liang Bill Tseng

2014-07-01

Full Text Available Optimization of design is an important step in obtaining tissue engineering scaffolds with appropriate shapes and inner microstructures. Different shapes and sizes of scaffolds are modeled using UGS NX 6.0 software with variable pore sizes. The quality issue we are concerned is the scaffold porosity, which is mainly caused by the fabrication inaccuracies. Bone scaffolds are usually characterized using a scanning electron microscope, but this study presents a new automated inspection and classification technique. Due to many numbers and size variations for the pores, the manual inspection of the fabricated scaffolds tends to be error-prone and costly. Manual inspection also raises the chance of contamination. Thus, non-contact, precise inspection is preferred. In this study, the critical dimensions are automatically measured by the vision camera. The measured data are analyzed to classify the quality characteristics. The automated inspection and classification techniques developed in this study are expected to improve the quality of the fabricated scaffolds and reduce the overall cost of manufacturing.

3D porous chitosan scaffolds suit survival and neural differentiation of dental pulp stem cells.

Science.gov (United States)

Feng, Xingmei; Lu, Xiaohui; Huang, Dan; Xing, Jing; Feng, Guijuan; Jin, Guohua; Yi, Xin; Li, Liren; Lu, Yuanzhou; Nie, Dekang; Chen, Xiang; Zhang, Lei; Gu, Zhifeng; Zhang, Xinhua

2014-08-01

A key aspect of cell replacement therapy in brain injury treatment is construction of a suitable biomaterial scaffold that can effectively carry and transport the therapeutic cells to the target area. In the present study, we created small 3D porous chitosan scaffolds through freeze-drying, and showed that these can support and enhance the differentiation of dental pulp stem cells (DPSCs) to nerve cells in vitro. The DPSCs were collected from the dental pulp of adult human third molars. At a swelling rate of ~84.33 ± 10.92 %, the scaffold displayed high porosity and interconnectivity of pores, as revealed by SEM. Cell counting kit-8 assay established the biocompatibility of the chitosan scaffold, supporting the growth and survival of DPSCs. The successful neural differentiation of DPSCs was assayed by RT-PCR, western blotting, and immunofluorescence. We found that the scaffold-attached DPSCs showed high expression of Nestin that decreased sharply following induction of differentiation. Exposure to the differentiation media also increased the expression of neural molecular markers Microtubule-associated protein 2, glial fibrillary acidic protein, and 2',3'-cyclic nucleotide phosphodiesterase. This study demonstrates that the granular 3D chitosan scaffolds are non-cytotoxic, biocompatible, and provide a conducive and favorable micro-environment for attachment, survival, and neural differentiation of DPSCs. These scaffolds have enormous potential to facilitate future advances in treatment of brain injury.

The 3-D Culture and In Vivo Growth of the Human Hepatocellular Carcinoma Cell Line HepG2 in a Self-Assembling Peptide Nanofiber Scaffold

International Nuclear Information System (INIS)

Wu, M.; Yang, Z.; Liu, Y.; Liu, B.; Zhao, X.

2010-01-01

We report the use of the RADA16-I scaffold to mimic the ECM microenvironment and support tumor cell adherence and survival. Cellular morphology, proliferation, adhesion ability, and in vivo tumor formation were studied in the human hepatocellular carcinoma cell line HepG2 in the 3-D RADA16-I scaffold. No significant differences in HepG2 cell proliferation, adhesion, and albumin secretion were observed in the peptide scaffold compared to collagen I. Furthermore, the HepG2 cells pre cultured in the peptide scaffold showed a higher proliferation rate and formed significantly bigger tumors when compared to cells grown on a traditional 2D monolayer, suggesting that the 3-D RADA16-I scaffold can mimic the tumor microenvironment and promote a malignant phenotype in HepG2 cells. Our results indicate that the RADA16-I scaffold can serve as an ideal model for tumorigenesis, growth, local invasion, and metastasis.

Morphology and characterization of 3D micro-porous structured chitosan scaffolds for tissue engineering.

Science.gov (United States)

Hsieh, Wen-Chuan; Chang, Chih-Pong; Lin, Shang-Ming

2007-06-15

This research studies the morphology and characterization of three-dimensional (3D) micro-porous structures produced from biodegradable chitosan for use as scaffolds for cells culture. The chitosan 3D micro-porous structures were produced by a simple liquid hardening method, which includes the processes of foaming by mechanical stirring without any chemical foaming agent added, and hardening by NaOH cross linking. The pore size and porosity were controlled with mechanical stirring strength. This study includes the morphology of chitosan scaffolds, the characterization of mechanical properties, water absorption properties and in vitro enzymatic degradation of the 3D micro-porous structures. The results show that chitosan 3D micro-porous structures were successfully produced. Better formation samples were obtained when chitosan concentration is at 1-3%, and concentration of NaOH is at 5%. Faster stirring rate would produce samples of smaller pore diameter, but when rotation speed reaches 4000 rpm and higher the changes in pore size is minimal. Water absorption would reduce along with the decrease of chitosan scaffolds' pore diameter. From stress-strain analysis, chitosan scaffolds' mechanical properties are improved when it has smaller pore diameter. From in vitro enzymatic degradation results, it shows that the disintegration rate of chitosan scaffolds would increase along with the processing time increase, but approaching equilibrium when the disintegration rate reaches about 20%.

Facile method of building hydroxyapatite 3D scaffolds assembled from porous hollow fibers enabling nutrient delivery

NARCIS (Netherlands)

Salamon, David; Da Silva Teixeira, Sandra; Dutczak, S.M.; Stamatialis, Dimitrios

2014-01-01

Nowadays, diffusion through scaffold and tissue usually limits transport, and forms potentially hypoxic regions. Several methods are used for preparation of 3D hydroxyapatite scaffolds, however, production of a scaffold including porous hollow fibers for nutrition delivery is difficult and

Effect of 3D-scaffold formation on differentiation and survival in human neural progenitor cells.

Science.gov (United States)

Ortinau, Stefanie; Schmich, Jürgen; Block, Stephan; Liedmann, Andrea; Jonas, Ludwig; Weiss, Dieter G; Helm, Christiane A; Rolfs, Arndt; Frech, Moritz J

2010-11-11

3D-scaffolds have been shown to direct cell growth and differentiation in many different cell types, with the formation and functionalisation of the 3D-microenviroment being important in determining the fate of the embedded cells. Here we used a hydrogel-based scaffold to investigate the influences of matrix concentration and functionalisation with laminin on the formation of the scaffolds, and the effect of these scaffolds on human neural progenitor cells cultured within them. In this study we used different concentrations of the hydrogel-based matrix PuraMatrix. In some experiments we functionalised the matrix with laminin I. The impact of concentration and treatment with laminin on the formation of the scaffold was examined with atomic force microscopy. Cells from a human fetal neural progenitor cell line were cultured in the different matrices, as well as in a 2D culture system, and were subsequently analysed with antibody stainings against neuronal markers. In parallel, the survival rate of the cells was determined by a live/dead assay. Atomic force microscopy measurements demonstrated that the matrices are formed by networks of isolated PuraMatrix fibres and aggregates of fibres. An increase of the hydrogel concentration led to a decrease in the mesh size of the scaffolds and functionalisation with laminin promoted aggregation of the fibres (bundle formation), which further reduces the density of isolated fibres. We showed that laminin-functionalisation is essential for human neural progenitor cells to build up 3D-growth patterns, and that proliferation of the cells is also affected by the concentration of matrix. In addition we found that 3D-cultures enhanced neuronal differentiation and the survival rate of the cells compared to 2D-cultures. Taken together, we have demonstrated a direct influence of the 3D-scaffold formation on the survival and neuronal differentiation of human neural progenitor cells. These findings emphasize the importance of optimizing 3

Enhanced In Vivo Bone and Blood Vessel Formation by Iron Oxide and Silica Doped 3D Printed Tricalcium Phosphate Scaffolds.

Science.gov (United States)

Bose, Susmita; Banerjee, Dishary; Robertson, Samuel; Vahabzadeh, Sahar

2018-05-04

Calcium phosphate (CaP) ceramics show significant promise towards bone graft applications because of the compositional similarity to inorganic materials of bone. With 3D printing, it is possible to create ceramic implants that closely mimic the geometry of human bone and can be custom-designed for unusual injuries or anatomical sites. The objective of the study was to optimize the 3D-printing parameters for the fabrication of scaffolds, with complex geometry, made from synthesized tricalcium phosphate (TCP) powder. This study was also intended to elucidate the mechanical and biological effects of the addition of Fe +3 and Si +4 in TCP implants in a rat distal femur model for 4, 8, and 12 weeks. Doped with Fe +3 and Si +4 TCP scaffolds with 3D interconnected channels were fabricated to provide channels for micronutrients delivery and improved cell-material interactions through bioactive fixation. Addition of Fe +3 into TCP enhanced early-stage new bone formation by increasing type I collagen production. Neovascularization was observed in the Si +4 doped samples after 12 weeks. These findings emphasize that the additive manufacturing of scaffolds with complex geometry from synthesized ceramic powder with modified chemistry is feasible and may serve as a potential candidate to introduce angiogenic and osteogenic properties to CaPs, leading to accelerated bone defect healing.

Collagenous matrix supported by a 3D-printed scaffold for osteogenic differentiation of dental pulp cells.

Science.gov (United States)

Fahimipour, Farahnaz; Dashtimoghadam, Erfan; Rasoulianboroujeni, Morteza; Yazdimamaghani, Mostafa; Khoshroo, Kimia; Tahriri, Mohammadreza; Yadegari, Amir; Gonzalez, Jose A; Vashaee, Daryoosh; Lobner, Douglas C; Jafarzadeh Kashi, Tahereh S; Tayebi, Lobat

2018-02-01

A systematic characterization of hybrid scaffolds, fabricated based on combinatorial additive manufacturing technique and freeze-drying method, is presented as a new platform for osteoblastic differentiation of dental pulp cells (DPCs). The scaffolds were consisted of a collagenous matrix embedded in a 3D-printed beta-tricalcium phosphate (β-TCP) as the mineral phase. The developed construct design was intended to achieve mechanical robustness owing to 3D-printed β-TCP scaffold, and biologically active 3D cell culture matrix pertaining to the Collagen extracellular matrix. The β-TCP precursor formulations were investigated for their flow-ability at various temperatures, which optimized for fabrication of 3D printed scaffolds with interconnected porosity. The hybrid constructs were characterized by 3D laser scanning microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and compressive strength testing. The in vitro characterization of scaffolds revealed that the hybrid β-TCP/Collagen constructs offer superior DPCs proliferation and alkaline phosphatase (ALP) activity compared to the 3D-printed β-TCP scaffold over three weeks. Moreover, it was found that the incorporation of TCP into the Collagen matrix improves the ALP activity. The presented results converge to suggest the developed 3D-printed β-TCP/Collagen hybrid constructs as a new platform for osteoblastic differentiation of DPCs for craniomaxillofacial bone regeneration. Copyright © 2017. Published by Elsevier Ltd.

Preparation of 3D fibroin/chitosan blend porous scaffold for tissue engineering via a simplified method.

Science.gov (United States)

Ruan, Yuhui; Lin, Hong; Yao, Jinrong; Chen, Zhengrong; Shao, Zhengzhong

2011-03-10

In this work, we developed a simple and flexible method to manufacture a 3D porous scaffold based on the blend of regenerated silk fibroin (RSF) and chitosan (CS). No crosslinker or other toxic reagents were used in this method. The pores of resulted 3D scaffolds were connected with each other, and their sizes could be easily controlled by the concentration of the mixed solution. Compared with pure RSF scaffolds, the water absorptivities of these RSF/CS blend scaffolds with significantly enhanced mechanical properties were greatly increased. The results of MTT and RT-PCR tests indicated that the chondrocytes grew very well in these blend RSF/CS porous scaffolds. This suggested that the RSF/CS blend scaffold prepared by this new method could be a promising candidate for applications in tissue engineering. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Mechanical, thermal and morphological characterisation of 3D porous Pennisetum purpureum/PLA biocomposites scaffold

Energy Technology Data Exchange (ETDEWEB)

Revati, R. [School of Mechatronic Engineering, Universiti Malaysia Perlis (UniMAP), Pauh Putra Campus, 02600 Arau, Perlis (Malaysia); Abdul Majid, M.S., E-mail: shukry@unimap.edu.my [School of Mechatronic Engineering, Universiti Malaysia Perlis (UniMAP), Pauh Putra Campus, 02600 Arau, Perlis (Malaysia); Ridzuan, M.J.M., E-mail: ridzuanjamir@unimap.edu.my [School of Mechatronic Engineering, Universiti Malaysia Perlis (UniMAP), Pauh Putra Campus, 02600 Arau, Perlis (Malaysia); Normahira, M., E-mail: normahira@unimap.edu.my [School of Mechatronic Engineering, Universiti Malaysia Perlis (UniMAP), Pauh Putra Campus, 02600 Arau, Perlis (Malaysia); Mohd Nasir, N.F., E-mail: nashrul@unimap.edu.my [School of Mechatronic Engineering, Universiti Malaysia Perlis (UniMAP), Pauh Putra Campus, 02600 Arau, Perlis (Malaysia); Rahman Y, M.N., E-mail: nurrahman@unimap.edu.my [School of Mechatronic Engineering, Universiti Malaysia Perlis (UniMAP), Pauh Putra Campus, 02600 Arau, Perlis (Malaysia); Gibson, A.G., E-mail: geoff.gibson@ncl.ac.uk [School of Mechanical and Systems Engineering, Newcastle University, Newcastle upon Tyne NE1 7RU (United Kingdom)

2017-06-01

The mechanical, thermal, and morphological properties of a 3D porous Pennisetum purpureum (PP)/polylactic acid (PLA) based scaffold were investigated. In this study, a scaffold containing P. purpureum and PLA was produced using the solvent casting and particulate leaching method. P. purpureum fibre, also locally known as Napier grass, is composed of 46% cellulose, 34% hemicellulose, and 20% lignin. PLA composites with various P. purpureum contents (10%, 20%, and 30%) were prepared and subsequently characterised. The morphologies, structures and thermal behaviours of the prepared composite scaffolds were characterised using field-emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). The morphology was studied using FESEM; the scaffold possessed 70–200 μm-sized pores with a high level of interconnectivity. The moisture content and mechanical properties of the developed porous scaffolds were further characterised. The P. purpureum/PLA scaffold had a greater porosity factor (99%) and compression modulus (5.25 MPa) than those of the pure PLA scaffold (1.73 MPa). From the results, it can be concluded that the properties of the highly porous P. purpureum/PLA scaffold developed in this study can be controlled and optimised. This can be used to facilitate the construction of implantable tissue-engineered cartilage. - Highlights: • High interconnected pores with 99% of porosity were observed for the scaffolds. • The pore sizes of the P. purpureum/PLA scaffolds ranged from 69 to 215 μm. • Addition of fillers improves the thermal properties and stability of the scaffolds. • PLA-PP{sub 30} scaffold showed enhanced compression modulus from 1.73 to 5.25 MPa.

Mechanical, thermal and morphological characterisation of 3D porous Pennisetum purpureum/PLA biocomposites scaffold

International Nuclear Information System (INIS)

Revati, R.; Abdul Majid, M.S.; Ridzuan, M.J.M.; Normahira, M.; Mohd Nasir, N.F.; Rahman Y, M.N.; Gibson, A.G.

2017-01-01

The mechanical, thermal, and morphological properties of a 3D porous Pennisetum purpureum (PP)/polylactic acid (PLA) based scaffold were investigated. In this study, a scaffold containing P. purpureum and PLA was produced using the solvent casting and particulate leaching method. P. purpureum fibre, also locally known as Napier grass, is composed of 46% cellulose, 34% hemicellulose, and 20% lignin. PLA composites with various P. purpureum contents (10%, 20%, and 30%) were prepared and subsequently characterised. The morphologies, structures and thermal behaviours of the prepared composite scaffolds were characterised using field-emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). The morphology was studied using FESEM; the scaffold possessed 70–200 μm-sized pores with a high level of interconnectivity. The moisture content and mechanical properties of the developed porous scaffolds were further characterised. The P. purpureum/PLA scaffold had a greater porosity factor (99%) and compression modulus (5.25 MPa) than those of the pure PLA scaffold (1.73 MPa). From the results, it can be concluded that the properties of the highly porous P. purpureum/PLA scaffold developed in this study can be controlled and optimised. This can be used to facilitate the construction of implantable tissue-engineered cartilage. - Highlights: • High interconnected pores with 99% of porosity were observed for the scaffolds. • The pore sizes of the P. purpureum/PLA scaffolds ranged from 69 to 215 μm. • Addition of fillers improves the thermal properties and stability of the scaffolds. • PLA-PP 30 scaffold showed enhanced compression modulus from 1.73 to 5.25 MPa.

Bioabsorbable poly-L/D-lactide (96/4) scaffold arthroplasty (RegJoint™) for trapeziometacarpal osteoarthritis: a 3-year follow-up study.

Science.gov (United States)

Mattila, Simo; Ainola, Mari; Waris, Eero

2018-05-01

The poly-L/D-lactide joint scaffold (RegJoint™) has recently been associated with adverse tissue reactions and osteolysis after partial trapeziectomy for trapeziometacarpal osteoarthritis. Twenty-two of 23 patients previously operated on with this scaffold were re-examined at a mean follow-up of 3.3 years (range 36-53 months). Overall, the results showed an unacceptably high rate of adverse tissue reactions related to the degradation process of the implant, resulting in a revision procedure in three patients. At final follow-up, at which point the implant had completely degraded, there were no signs of ongoing adverse tissue reactions. There was a significant decrease in pain, increase in strength and subjective improvement in function at final follow-up compared with the pre-operative results in patients who had not undergone revision surgery. However, owing to the high incidence of adverse tissue reactions, the use of the implant has been discontinued in the treatment of trapeziometacarpal osteoarthritis. IV.

Composite PLA/PEG/nHA/Dexamethasone Scaffold Prepared by 3D Printing for Bone Regeneration.

Science.gov (United States)

Li, Xiaoyuan; Wang, Yu; Wang, Zigui; Qi, Yanxin; Li, Linlong; Zhang, Peibiao; Chen, Xuesi; Huang, Yubin

2018-04-24

3D printing has become an essential part of bone tissue engineering and attracts great attention for the fabrication of bioactive scaffolds. Combining this rapid manufacturing technique with chemical precipitation, biodegradable 3D scaffold composed of polymer matrix (polylactic acid and polyethylene glycol), ceramics (nano hydroxyapatite), and drugs (dexamethasone (Dex)) is prepared. Results of water contact angle, differential scanning calorimeter, and mechanical tests confirm that incorporation of Dex leads to significantly improved wettability, higher crystallinity degree, and tunable degradation rates. In vitro experiment with mouse MC3T3-E1 cells implies that Dex released from scaffolds is not beneficial for early cell proliferation, but it improves late alkaline phosphatase secretion and mineralization significantly. Anti-inflammation assay of murine RAW 264.7 cells proves that Dex released from all the scaffolds successfully suppresses lipopolysaccharide induced interleukin-6 and inducible nitric oxide synthase secretion by M1 macrophages. Further in vivo experiment on rat calvarial defects indicates that scaffolds containing Dex promote osteoinduction and osteogenic response and would be promising candidates for clinical applications. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Establishment of 3D culture and induction of osteogenic differentiation of pre-osteoblasts using wet-collected aligned scaffolds

Energy Technology Data Exchange (ETDEWEB)

Ding, Huifen [Hubei-MOSTKLOS & KLOBM, School and Hospital of Stomatology, Wuhan University, Wuhan 430079 (China); Chongqing Affiliated Hospital of Stomatology, Chongqing University of Medical Sciences, Chongqing 400015 (China); Zhong, Junwen [Wuhan National Laboratory for Optoelectronics, School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074 (China); Xu, Fei; Song, Fangfang; Yin, Miao; Wu, Yanru; Hu, Qiyi [Hubei-MOSTKLOS & KLOBM, School and Hospital of Stomatology, Wuhan University, Wuhan 430079 (China); Wang, Jiawei, E-mail: wangjwei@hotmail.com [Hubei-MOSTKLOS & KLOBM, School and Hospital of Stomatology, Wuhan University, Wuhan 430079 (China)

2017-02-01

Aligned fibrous scaffolds have attracted much interest in bone tissue engineering, because they are supposed to induce osteogenic differentiation. For the first time, aligned silk fibroin nanofibres were loosely packed using a novel wet-collection electrospinning method. Moreover, three-dimensional (3D) culture of MC3T3-E1 pre-osteoblasts was established on these fibrous scaffolds. Physicochemical properties of the scaffolds and the behaviour of MC3T3-E1 pre-osteoblasts on the scaffolds were analysed and compared with scaffolds obtained using traditional method. Ethanol bath improved the uniformity and alignment of the fibres and increased the thickness and porosity of the scaffolds. Structures of the fibres were well maintained after immediate crosslinking in ethanol. Cells on the wet-collected scaffolds exhibited more ordered arrangement and elongated morphology as well as faster and deeper infiltration. The ordered infiltration resulted in the establishment of the 3D culture of cells, promoting proliferation and osteogenic differentiation of the pre-osteoblasts. Thus, the wet-collected aligned scaffolds with improved topographical and physicochemical properties presents significant potential application in bone regeneration. - Highlights: • Aligned silk fibroin nanofibres were loosely packed using a novel wet-collection electrospinning method. • Structural properties of the aligned nanofibres were improved. • Three-dimensional culture of MC3T3-E1 pre-osteoblasts was established. • The arrangement, morphology, infiltration, proliferation and osteogenic differentiation of cells were enhanced.

3D-Printed Atsttrin-Incorporated Alginate/Hydroxyapatite Scaffold Promotes Bone Defect Regeneration with TNF/TNFR Signaling Involvement.

Science.gov (United States)

Wang, Quan; Xia, Qingqing; Wu, Yan; Zhang, Xiaolei; Wen, Feiqiu; Chen, Xiaowen; Zhang, Shufang; Heng, Boon Chin; He, Yong; Ouyang, Hong-Wei

2015-08-05

High expression levels of pro-inflammatory tumor necrosis factor (TNF)-α within bone defects can decelerate and impair bone regeneration. However, there are few available bone scaffolds with anti-inflammatory function. The progranulin (PGRN)-derived engineered protein, Atsttrin, is known to exert antagonistic effects on the TNF-α function. Hence, this study investigates whether 3D-printed Atsttrin-incorporated alginate(Alg)/hydroxyapatite(nHAp) scaffolds can facilitate bone healing through affecting the TNF/TNFR signaling. A 3D bioprinting system is used to fabricate Atsttrin-Alg/nHAp composite scaffolds, and the Atsttrin release from this scaffold is characterized, followed by evaluation of its efficacy on bone regeneration both in vitro and in vivo. The 3D-printed Atsttrin-Alg/nHAp scaffold exhibits a precisely defined structure, can sustain Atsttrin release for at least 5 days, has negligible cytotoxicity, and supports cell adhesion. Atsttrin can also attenuate the suppressive effects of TNF-α on BMP-2-induced osteoblastic differentiation in vitro. The 3D-printed Atsttrin-Alg/nHAp scaffold significantly reduces the number of TNF-α positive cells within wound sites, 7 days after post-calvarial defect surgery. Additionally, histological staining and X-ray scanning results also show that the 3D-printed Atsttrin-Alg/nHAp scaffold enhances the regeneration of mice calvarial bone defects. These findings thus demonstrate that the precise structure and anti-inflammatory properties of 3D-printed Atsttrin-Alg/nHAp scaffolds may promote bone defect repair. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A multi-scale controlled tissue engineering scaffold prepared by 3D printing and NFES technology

Directory of Open Access Journals (Sweden)

Feifei Yan

2014-03-01

Full Text Available The current focus in the field of life science is the use of tissue engineering scaffolds to repair human organs, which has shown great potential in clinical applications. Extracellular matrix morphology and the performance and internal structure of natural organs are required to meet certain requirements. Therefore, integrating multiple processes can effectively overcome the limitations of the individual processes and can take into account the needs of scaffolds for the material, structure, mechanical properties and many other aspects. This study combined the biological 3D printing technology and the near-field electro-spinning (NFES process to prepare a multi-scale controlled tissue engineering scaffold. While using 3D printing technology to directly prepare the macro-scaffold, the compositing NFES process to build tissue micro-morphology ultimately formed a tissue engineering scaffold which has the specific extracellular matrix structure. This scaffold not only takes into account the material, structure, performance and many other requirements, but also focuses on resolving the controllability problems in macro- and micro-forming which further aim to induce cell directed differentiation, reproduction and, ultimately, the formation of target tissue organs. It has in-depth immeasurable significance to build ideal scaffolds and further promote the application of tissue engineering.

Evaluation of the effects of nano-TiO2 on bioactivity and mechanical properties of nano bioglass-P3HB composite scaffold for bone tissue engineering.

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Bakhtiyari, Sanaz Soleymani Eil; Karbasi, Saeed; Monshi, Ahmad; Montazeri, Mahbobeh

2016-01-01

To emulate bone structure, porous composite scaffold with suitable mechanical properties should be designed. In this research the effects of nano-titania (nTiO2) on the bioactivity and mechanical properties of nano-bioglass-poly-3-hydroxybutyrate (nBG/P3HB)-composite scaffold were evaluated. First, nBG powder was prepared by melting method of pure raw materials at a temperature of 1400 °C and then the porous ceramic scaffold of nBG/nTiO2 with 30 wt% of nBG containing different weight ratios of nTiO2 (3, 6, and 9 wt% of nTiO2 with grain size of 35-37 nm) was prepared by using polyurethane sponge replication method. Then the scaffolds were coated with P3HB in order to increase the scaffold's mechanical properties. Mechanical strength and modulus of scaffolds were improved by adding nTiO2 to nBG scaffold and adding P3HB to nBG/nTiO2 composite scaffold. The results of the compressive strength and porosity tests showed that the best scaffold is 30 wt% of nBG with 6 wt% of nTiO2 composite scaffold immersed for 30 s in P3HB with 79.5-80 % of porosity in 200-600 μm, with a compressive strength of 0.15 MPa and a compressive modulus of 30 MPa, which is a good candidate for bone tissue engineering. To evaluate the bioactivity of the scaffold, the simulated body fluid (SBF) solution was used. The best scaffold with 30 wt% of nBG, 6 wt% of P3HB and 6 wt% of nTiO2 was immersed in SBF for 4 weeks at an incubation temperature of 37 °C. The bioactivity of the scaffolds was characterized by AAS, SEM, EDXA and XRD. The results of bioactivity showed that bone-like apatite layer formed well at scaffold surface and adding nTiO2 to nBG/P3HB composite scaffold helped increase the bioactivity rate.

Role of scaffold mean pore size in meniscus regeneration.

Science.gov (United States)

Zhang, Zheng-Zheng; Jiang, Dong; Ding, Jian-Xun; Wang, Shao-Jie; Zhang, Lei; Zhang, Ji-Ying; Qi, Yan-Song; Chen, Xue-Si; Yu, Jia-Kuo

2016-10-01

Recently, meniscus tissue engineering offers a promising management for meniscus regeneration. Although rarely reported, the microarchitectures of scaffolds can deeply influence the behaviors of endogenous or exogenous stem/progenitor cells and subsequent tissue formation in meniscus tissue engineering. Herein, a series of three-dimensional (3D) poly(ε-caprolactone) (PCL) scaffolds with three distinct mean pore sizes (i.e., 215, 320, and 515μm) were fabricated via fused deposition modeling. The scaffold with the mean pore size of 215μm significantly improved both the proliferation and extracellular matrix (ECM) production/deposition of mesenchymal stem cells compared to all other groups in vitro. Moreover, scaffolds with mean pore size of 215μm exhibited the greatest tensile and compressive moduli in all the acellular and cellular studies. In addition, the relatively better results of fibrocartilaginous tissue formation and chondroprotection were observed in the 215μm scaffold group after substituting the rabbit medial meniscectomy for 12weeks. Overall, the mean pore size of 3D-printed PCL scaffold could affect cell behavior, ECM production, biomechanics, and repair effect significantly. The PCL scaffold with mean pore size of 215μm presented superior results both in vitro and in vivo, which could be an alternative for meniscus tissue engineering. Meniscus tissue engineering provides a promising strategy for meniscus regeneration. In this regard, the microarchitectures (e.g., mean pore size) of scaffolds remarkably impact the behaviors of cells and subsequent tissue formation, which has been rarely reported. Herein, three three-dimensional poly(ε-caprolactone) scaffolds with different mean pore sizes (i.e., 215, 320, and 515μm) were fabricated via fused deposition modeling. The results suggested that the mean pore size significantly affected the behaviors of endogenous or exogenous stem/progenitor cells and subsequent tissue formation. This study furthers

In vitro degradation of a 3D porous Pennisetum purpureum/PLA biocomposite scaffold.

Science.gov (United States)

Revati, R; Majid, M S Abdul; Ridzuan, M J M; Basaruddin, K S; Rahman Y, M N; Cheng, E M; Gibson, A G

2017-10-01

The in vitro degradation and mechanical properties of a 3D porous Pennisetum purpureum (PP)/polylactic acid (PLA)-based scaffold were investigated. In this study, composite scaffolds with PP to PLA ratios of 0%, 10%, 20%, and 30% were immersed in a PBS solution at 37°C for 40 days. Compression tests were conducted to evaluate the compressive strength and modulus of the scaffolds, according to ASTM F451-95. The compression strength of the scaffolds was found to increase from 1.94 to 9.32MPa, while the compressive modulus increased from 1.73 to 5.25MPa as the fillers' content increased from 0wt% to 30wt%. Moreover, field emission scanning electron microscopy (FESEM) and X-ray diffraction were employed to observe and analyse the microstructure and fibre-matrix interface. Interestingly, the degradation rate was reduced for the PLA/PP 20 scaffold, though insignificantly, this could be attributed to the improved mechanical properties and stronger fibre-matrix interface. Microstructure changes after degradation were observed using FESEM. The FESEM results indicated that a strong fibre-matrix interface was formed in the PLA/PP 20 scaffold, which reflected the addition of P. purpureum into PLA decreasing the degradation rate compared to in pure PLA scaffolds. The results suggest that the P. purpureum/PLA scaffold degradation rate can be altered and controlled to meet requirements imposed by a given tissue engineering application. Copyright © 2017 Elsevier Ltd. All rights reserved.

Evaluation of 3D-Printed Polycaprolactone Scaffolds Coated with Freeze-Dried Platelet-Rich Plasma for Bone Regeneration

Directory of Open Access Journals (Sweden)

Junda Li

2017-07-01

Full Text Available Three-dimensional printing is one of the most promising techniques for the manufacturing of scaffolds for bone tissue engineering. However, a pure scaffold is limited by its biological properties. Platelet-rich plasma (PRP has been shown to have the potential to improve the osteogenic effect. In this study, we improved the biological properties of scaffolds by coating 3D-printed polycaprolactone (PCL scaffolds with freeze-dried and traditionally prepared PRP, and we evaluated these scaffolds through in vitro and in vivo experiments. In vitro, we evaluated the interaction between dental pulp stem cells (DPSCs and the scaffolds by measuring cell proliferation, alkaline phosphatase (ALP activity, and osteogenic differentiation. The results showed that freeze-dried PRP significantly enhanced ALP activity and the mRNA expression levels of osteogenic genes (ALP, RUNX2 (runt-related gene-2, OCN (osteocalcin, OPN (osteopontin of DPSCs (p < 0.05. In vivo, 5 mm calvarial defects were created, and the PRP-PCL scaffolds were implanted. The data showed that compared with traditional PRP-PCL scaffolds or bare PCL scaffolds, the freeze-dried PRP-PCL scaffolds induced significantly greater bone formation (p < 0.05. All these data suggest that coating 3D-printed PCL scaffolds with freeze-dried PRP can promote greater osteogenic differentiation of DPSCs and induce more bone formation, which may have great potential in future clinical applications.

Bone regeneration in critical bone defects using three-dimensionally printed β-tricalcium phosphate/hydroxyapatite scaffolds is enhanced by coating scaffolds with either dipyridamole or BMP-2.

Science.gov (United States)

Ishack, Stephanie; Mediero, Aranzazu; Wilder, Tuere; Ricci, John L; Cronstein, Bruce N

2017-02-01

Bone defects resulting from trauma or infection need timely and effective treatments to restore damaged bone. Using specialized three-dimensional (3D) printing technology we have created custom 3D scaffolds of hydroxyapatite (HA)/beta-tri-calcium phosphate (β-TCP) to promote bone repair. To further enhance bone regeneration we have coated the scaffolds with dipyridamole, an agent that increases local adenosine levels by blocking cellular uptake of adenosine. Nearly 15% HA:85% β-TCP scaffolds were designed using Robocad software, fabricated using a 3D Robocasting system, and sintered at 1100°C for 4 h. Scaffolds were coated with BMP-2 (200 ng mL -1 ), dypiridamole 100 µM or saline and implanted in C57B6 and adenosine A2A receptor knockout (A2AKO) mice with 3 mm cranial critical bone defects for 2-8 weeks. Dipyridamole release from scaffold was assayed spectrophotometrically. MicroCT and histological analysis were performed. Micro-computed tomography (microCT) showed significant bone formation and remodeling in HA/β-TCP-dipyridamole and HA/β-TCP-BMP-2 scaffolds when compared to scaffolds immersed in vehicle at 2, 4, and 8 weeks (n = 5 per group; p ≤ 0.05, p ≤ 0.05, and p ≤ 0.01, respectively). Histological analysis showed increased bone formation and a trend toward increased remodeling in HA/β-TCP- dipyridamole and HA/β-TCP-BMP-2 scaffolds. Coating scaffolds with dipyridamole did not enhance bone regeneration in A2AKO mice. In conclusion, scaffolds printed with HA/β-TCP promote bone regeneration in critical bone defects and coating these scaffolds with agents that stimulate A2A receptors and growth factors can further enhance bone regeneration. These coated scaffolds may be very useful for treating critical bone defects due to trauma, infection or other causes. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 366-375, 2017. © 2015 Wiley Periodicals, Inc.

Design and Fabrication of 3D printed Scaffolds with a Mechanical Strength Comparable to Cortical Bone to Repair Large Bone Defects

Science.gov (United States)

Roohani-Esfahani, Seyed-Iman; Newman, Peter; Zreiqat, Hala

2016-01-01

A challenge in regenerating large bone defects under load is to create scaffolds with large and interconnected pores while providing a compressive strength comparable to cortical bone (100-150 MPa). Here we design a novel hexagonal architecture for a glass-ceramic scaffold to fabricate an anisotropic, highly porous three dimensional scaffolds with a compressive strength of 110 MPa. Scaffolds with hexagonal design demonstrated a high fatigue resistance (1,000,000 cycles at 1-10 MPa compressive cyclic load), failure reliability and flexural strength (30 MPa) compared with those for conventional architecture. The obtained strength is 150 times greater than values reported for polymeric and composite scaffolds and 5 times greater than reported values for ceramic and glass scaffolds at similar porosity. These scaffolds open avenues for treatment of load bearing bone defects in orthopaedic, dental and maxillofacial applications.

Discovery of Mixed Pharmacology Melanocortin-3 Agonists and Melanocortin-4 Receptor Tetrapeptide Antagonist Compounds (TACOs) Based on the Sequence Ac-Xaa1-Arg-(pI)DPhe-Xaa4-NH2.

Science.gov (United States)

Doering, Skye R; Freeman, Katie T; Schnell, Sathya M; Haslach, Erica M; Dirain, Marvin; Debevec, Ginamarie; Geer, Phaedra; Santos, Radleigh G; Giulianotti, Marc A; Pinilla, Clemencia; Appel, Jon R; Speth, Robert C; Houghten, Richard A; Haskell-Luevano, Carrie

2017-05-25

The centrally expressed melanocortin-3 and -4 receptors (MC3R/MC4R) have been studied as possible targets for weight management therapies, with a preponderance of studies focusing on the MC4R. Herein, a novel tetrapeptide scaffold [Ac-Xaa 1 -Arg-(pI)DPhe-Xaa 4 -NH 2 ] is reported. The scaffold was derived from results obtained from a MC3R mixture-based positional scanning campaign. From these results, a set of 48 tetrapeptides were designed and pharmacologically characterized at the mouse melanocortin-1, -3, -4, and -5 receptors. This resulted in the serendipitous discovery of nine compounds that were MC3R agonists (EC 50 DPhe-Tic-NH 2 ], 1 [Ac-His-Arg-(pI)DPhe-Tic-NH 2 ], and 41 [Ac-Arg-Arg-(pI)DPhe-DNal(2')-NH 2 ] were more potent (EC 50 DPhe-Arg-Trp-NH 2 . This template contains a sequentially reversed "Arg-(pI)DPhe" motif with respect to the classical "Phe-Arg" melanocortin signaling motif, which results in pharmacology that is first-in-class for the central melanocortin receptors.

3D printing for the design and fabrication of polymer-based gradient scaffolds.

Science.gov (United States)

Bracaglia, Laura G; Smith, Brandon T; Watson, Emma; Arumugasaamy, Navein; Mikos, Antonios G; Fisher, John P

2017-07-01

To accurately mimic the native tissue environment, tissue engineered scaffolds often need to have a highly controlled and varied display of three-dimensional (3D) architecture and geometrical cues. Additive manufacturing in tissue engineering has made possible the development of complex scaffolds that mimic the native tissue architectures. As such, architectural details that were previously unattainable or irreproducible can now be incorporated in an ordered and organized approach, further advancing the structural and chemical cues delivered to cells interacting with the scaffold. This control over the environment has given engineers the ability to unlock cellular machinery that is highly dependent upon the intricate heterogeneous environment of native tissue. Recent research into the incorporation of physical and chemical gradients within scaffolds indicates that integrating these features improves the function of a tissue engineered construct. This review covers recent advances on techniques to incorporate gradients into polymer scaffolds through additive manufacturing and evaluate the success of these techniques. As covered here, to best replicate different tissue types, one must be cognizant of the vastly different types of manufacturing techniques available to create these gradient scaffolds. We review the various types of additive manufacturing techniques that can be leveraged to fabricate scaffolds with heterogeneous properties and discuss methods to successfully characterize them. Additive manufacturing techniques have given tissue engineers the ability to precisely recapitulate the native architecture present within tissue. In addition, these techniques can be leveraged to create scaffolds with both physical and chemical gradients. This work offers insight into several techniques that can be used to generate graded scaffolds, depending on the desired gradient. Furthermore, it outlines methods to determine if the designed gradient was achieved. This review

Synthesis of Tetrasubstituted Thieno[3,2-b]pyridin-5(4H)-one Derivatives as a Heterocyclic Scaffold for Multisite-specific Fluorous Fluorescent Tagging and Fluorous Solid-Phase Extraction

Energy Technology Data Exchange (ETDEWEB)

Jeon, Moon-Kook; Yi, Su-Jin [Korea Research Institute of Chemical Technology, Daejeon (Korea, Republic of); Son, Seung Uk [Sungkyunkwan University, Suwon (Korea, Republic of)

2016-08-15

Tetrasubstituted thieno[3,2-b]pyridin-5(4H)-one derivatives were selected as a highly functionalized heterocyclic scaffold for a multisite-specific tagging process utilizing a previously devised fluorous fluorescent tag system. A suitable synthetic method was established for the 7-alkoxy-2,4,6-risubstituted-thieno[3,2-b] pyridin-5(4H)-one derivatives, and incorporating t-butoxycarbonyl-functionalized building blocks into the reaction sequence produced precursors that could be used in the tagging process. Fluorous solid-phase extraction facilitated the purification of the tagged target compounds after a series of reactions, including t-Bu deprotection/N-hydroxysuccinimidyl ester formation/amidation.

Synthesis of Tetrasubstituted Thieno[3,2-b]pyridin-5(4H)-one Derivatives as a Heterocyclic Scaffold for Multisite-specific Fluorous Fluorescent Tagging and Fluorous Solid-Phase Extraction

International Nuclear Information System (INIS)

Jeon, Moon-Kook; Yi, Su-Jin; Son, Seung Uk

2016-01-01

Tetrasubstituted thieno[3,2-b]pyridin-5(4H)-one derivatives were selected as a highly functionalized heterocyclic scaffold for a multisite-specific tagging process utilizing a previously devised fluorous fluorescent tag system. A suitable synthetic method was established for the 7-alkoxy-2,4,6-risubstituted-thieno[3,2-b] pyridin-5(4H)-one derivatives, and incorporating t-butoxycarbonyl-functionalized building blocks into the reaction sequence produced precursors that could be used in the tagging process. Fluorous solid-phase extraction facilitated the purification of the tagged target compounds after a series of reactions, including t-Bu deprotection/N-hydroxysuccinimidyl ester formation/amidation.

Magnetic responsive hydroxyapatite composite scaffolds construction for bone defect reparation.

Science.gov (United States)

Zeng, Xiao Bo; Hu, Hao; Xie, Li Qin; Lan, Fang; Jiang, Wen; Wu, Yao; Gu, Zhong Wei

2012-01-01

In recent years, interest in magnetic biomimetic scaffolds for tissue engineering has increased considerably. A type of magnetic scaffold composed of magnetic nanoparticles (MNPs) and hydroxyapatite (HA) for bone repair has been developed by our research group. In this study, to investigate the influence of the MNP content (in the scaffolds) on the cell behaviors and the interactions between the magnetic scaffold and the exterior magnetic field, a series of MNP-HA magnetic scaffolds with different MNP contents (from 0.2% to 2%) were fabricated by immersing HA scaffold into MNP colloid. ROS 17/2.8 and MC3T3-E1 cells were cultured on the scaffolds in vitro, with and without an exterior magnetic field, respectively. The cell adhesion, proliferation and differentiation were evaluated via scanning electron microscopy; confocal laser scanning microscopy; and 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), alkaline phosphatase, and bone gla protein activity tests. The results demonstrated the positive influence of the magnetic scaffolds on cell adhesion, proliferation, and differentiation. Further, a higher amount of MNPs on the magnetic scaffolds led to more significant stimulation. The magnetic scaffold can respond to the exterior magnetic field and engender some synergistic effect to intensify the stimulating effect of a magnetic field to the proliferation and differentiation of cells.

Nanorod mediated collagen scaffolds as extra cellular matrix mimics

International Nuclear Information System (INIS)

Vedhanayagam, Mohan; Nair, Balachandran Unni; Sreeram, Kalarical Janardhanan; Mohan, Ranganathan

2015-01-01

Creating collagen scaffolds that mimic extracellular matrices without using toxic exogenous materials remains a big challenge. A new strategy to create scaffolds through end-to-end crosslinking through functionalized nanorods leading to well-designed architecture is presented here. Self-assembled scaffolds with a denaturation temperature of 110 °C, porosity of 70%, pore size of 0.32 μm and Young’s modulus of 231 MPa were developed largely driven by imine bonding between 3-mercapto-1-propanal (MPA) functionalized ZnO nanorods and collagen. The mechanical properties obtained were much higher than that of native collagen, collagen—MPA, collagen—3-mercapto-1-propanol (3MPOH) or collagen- 3-MPOH-ZnO, clearly bringing out the relevance of nanorod mediated assembly of fibrous networks. This new strategy has led to scaffolds with mechanical properties much higher than earlier reports and can provide support for cell growth and facilitation of cell attachment. (paper)

3D printed alendronate-releasing poly(caprolactone) porous scaffolds enhance osteogenic differentiation and bone formation in rat tibial defects.

Science.gov (United States)

Kim, Sung Eun; Yun, Young-Pil; Shim, Kyu-Sik; Kim, Hak-Jun; Park, Kyeongsoon; Song, Hae-Ryong

2016-09-29

The aim of this study was to evaluate the in vitro osteogenic effects and in vivo new bone formation of three-dimensional (3D) printed alendronate (Aln)-releasing poly(caprolactone) (PCL) (Aln/PCL) scaffolds in rat tibial defect models. 3D printed Aln/PCL scaffolds were fabricated via layer-by-layer deposition. The fabricated Aln/PCL scaffolds had high porosity and an interconnected pore structure and showed sustained Aln release. In vitro studies showed that MG-63 cells seeded on the Aln/PCL scaffolds displayed increased alkaline phosphatase (ALP) activity and calcium content in a dose-dependent manner when compared with cell cultures in PCL scaffolds. In addition, in vivo animal studies and histologic evaluation showed that Aln/PCL scaffolds implanted in a rat tibial defect model markedly increased new bone formation and mineralized bone tissues in a dose-dependent manner compared to PCL-only scaffolds. Our results show that 3D printed Aln/PCL scaffolds are promising templates for bone tissue engineering applications.

Dynamic mechanical properties of 3D fiber-deposited PEOT/PBT scaffolds: An experimental and numerical analysis.

NARCIS (Netherlands)

Moroni, Lorenzo; Poort, G.; van Keulen, F.; de Wijn, J.R.; van Blitterswijk, Clemens

2006-01-01

Mechanical properties of three-dimensional (3D) scaffolds can be appropriately modulated through novel fabrication techniques like 3D fiber deposition (3DF), by varying scaffold's pore size and shape. Dynamic stiffness, in particular, can be considered as an important property to optimize the

Surface-modified functionalized polycaprolactone scaffolds for bone repair

DEFF Research Database (Denmark)

Jensen, Jonas; Rölfing, Jan Hendrik Duedal; Svend Le, Dang Quang

2014-01-01

A porcine calvaria defect study was carried out to investigate the bone repair potential of three-dimensional (3D)-printed poly-ε-caprolactone (PCL) scaffolds embedded with nanoporous PCL. A microscopic grid network was created by rapid prototyping making a 3D-fused deposition model (FDM-PCL). Af......A porcine calvaria defect study was carried out to investigate the bone repair potential of three-dimensional (3D)-printed poly-ε-caprolactone (PCL) scaffolds embedded with nanoporous PCL. A microscopic grid network was created by rapid prototyping making a 3D-fused deposition model (FDM......-PCL). Afterward, the FDM-PCL scaffolds were infused with a mixture of PCL, water, and 1,4-dioxane and underwent a thermal-induced phase separation (TIPS) followed by lyophilization. The TIPS process lead to a nanoporous structure shielded by the printed microstructure (NSP-PCL). Sixteen Landrace pigs were divided...... into two groups with 8 and 12 weeks follow-up, respectively. A total of six nonpenetrating holes were drilled in the calvaria of each animal. The size of the cylindrical defects was h 10 mm and Ø 10 mm. The defects were distributed randomly using following groups: (a) NSP-PCL scaffold, (b) FDM-PCL scaffold...

Parallel fabrication of macroporous scaffolds.

Science.gov (United States)

Dobos, Andrew; Grandhi, Taraka Sai Pavan; Godeshala, Sudhakar; Meldrum, Deirdre R; Rege, Kaushal

2018-07-01

Scaffolds generated from naturally occurring and synthetic polymers have been investigated in several applications because of their biocompatibility and tunable chemo-mechanical properties. Existing methods for generation of 3D polymeric scaffolds typically cannot be parallelized, suffer from low throughputs, and do not allow for quick and easy removal of the fragile structures that are formed. Current molds used in hydrogel and scaffold fabrication using solvent casting and porogen leaching are often single-use and do not facilitate 3D scaffold formation in parallel. Here, we describe a simple device and related approaches for the parallel fabrication of macroporous scaffolds. This approach was employed for the generation of macroporous and non-macroporous materials in parallel, in higher throughput and allowed for easy retrieval of these 3D scaffolds once formed. In addition, macroporous scaffolds with interconnected as well as non-interconnected pores were generated, and the versatility of this approach was employed for the generation of 3D scaffolds from diverse materials including an aminoglycoside-derived cationic hydrogel ("Amikagel"), poly(lactic-co-glycolic acid) or PLGA, and collagen. Macroporous scaffolds generated using the device were investigated for plasmid DNA binding and cell loading, indicating the use of this approach for developing materials for different applications in biotechnology. Our results demonstrate that the device-based approach is a simple technology for generating scaffolds in parallel, which can enhance the toolbox of current fabrication techniques. © 2018 Wiley Periodicals, Inc.

Silk scaffolds connected with different naturally occurring biomaterials for prostate cancer cell cultivation in 3D.

Science.gov (United States)

Bäcker, Anne; Erhardt, Olga; Wietbrock, Lukas; Schel, Natalia; Göppert, Bettina; Dirschka, Marian; Abaffy, Paul; Sollich, Thomas; Cecilia, Angelica; Gruhl, Friederike J

2017-02-01

In the present work, different biopolymer blend scaffolds based on the silk protein fibroin from Bombyx mori (BM) were prepared via freeze-drying method. The chemical, structural, and mechanical properties of the three dimensional (3D) porous silk fibroin (SF) composite scaffolds of gelatin, collagen, and chitosan as well as SF from Antheraea pernyi (AP) and the recombinant spider silk protein spidroin (SSP1) have been systematically investigated, followed by cell culture experiments with epithelial prostate cancer cells (LNCaP) up to 14 days. Compared to the pure SF scaffold of BM, the blend scaffolds differ in porous morphology, elasticity, swelling behavior, and biochemical composition. The new composite scaffold with SSP1 showed an increased swelling degree and soft tissue like elastic properties. Whereas, in vitro cultivation of LNCaP cells demonstrated an increased growth behavior and spheroid formation within chitosan blended scaffolds based on its remarkable porosity, which supports nutrient supply matrix. Results of this study suggest that silk fibroin matrices are sufficient and certain SF composite scaffolds even improve 3D cell cultivation for prostate cancer research compared to matrices based on pure biomaterials or synthetic polymers. © 2016 Wiley Periodicals, Inc.

Use of Interim Scaffolding and Neotissue Development to Produce a Scaffold-Free Living Hyaline Cartilage Graft.

Science.gov (United States)

Lau, Ting Ting; Leong, Wenyan; Peck, Yvonne; Su, Kai; Wang, Dong-An

2015-01-01

The fabrication of three-dimensional (3D) constructs relies heavily on the use of biomaterial-based scaffolds. These are required as mechanical supports as well as to translate two-dimensional cultures to 3D cultures for clinical applications. Regardless of the choice of scaffold, timely degradation of scaffolds is difficult to achieve and undegraded scaffold material can lead to interference in further tissue development or morphogenesis. In cartilage tissue engineering, hydrogel is the highly preferred scaffold material as it shares many similar characteristics with native cartilaginous matrix. Hence, we employed gelatin microspheres as porogens to create a microcavitary alginate hydrogel as an interim scaffold to facilitate initial chondrocyte 3D culture and to establish a final scaffold-free living hyaline cartilaginous graft (LhCG) for cartilage tissue engineering.

In vitro biocompatibility of 45S5 Bioglass-derived glass-ceramic scaffolds coated with poly(3-hydroxybutyrate).

Science.gov (United States)

Bretcanu, Oana; Misra, Superb; Roy, Ipsita; Renghini, Chiara; Fiori, Fabrizio; Boccaccini, Aldo R; Salih, Vehid

2009-02-01

The aim of this work was to study the in vitro biocompatibility of glass-ceramic scaffolds based on 45S5 Bioglass, using a human osteosarcoma cell line (HOS-TE85). The highly porous scaffolds were produced by the foam replication technique. Two different types of scaffolds with different porosities were analysed. They were coated with a biodegradable polymer, poly(3-hydroxybutyrate) (P(3HB)). The scaffold bioactivity was evaluated by soaking in a simulated body fluid (SBF) for different durations. Compression strength tests were performed before and after immersion in SBF. These experiments showed that the scaffolds are highly bioactive, as after a few days of immersion in SBF a hydroxyapatite-like layer was formed on the scaffold's surface. It was also observed that P(3HB)-coated samples exhibited higher values of compression strength than uncoated samples. Biocompatibility assessment was carried out by qualitative evaluation of cell morphology after different culture periods, using scanning electron microscopy, while cell proliferation was determined by using the AlamarBlue assay. Alkaline phosphatase (ALP) and osteocalcin (OC) assays were used as quantitative in vitro indicators of osteoblast function. Two different types of medium were used for ALP and OC tests: normal supplemented medium and osteogenic medium. HOS cells were seeded and cultured onto the scaffolds for up to 2 weeks. The AlamarBlue assay showed that cells were able to proliferate and grow on the scaffold surface. After 7 days in culture, the P(3HB)-coated samples had a higher number of cells on their surfaces than the uncoated samples. Regarding ALP- and OC-specific activity, no significant differences were found between samples with different pore sizes. All scaffolds containing osteogenic medium seemed to have a slightly higher level of ALP and OC concentration. These experiments confirmed that Bioglass/P(3HB) scaffolds have potential as osteoconductive tissue engineering substrates for

Incorporating simvastatin/poloxamer 407 hydrogel into 3D-printed porous Ti6Al4V scaffolds for the promotion of angiogenesis, osseointegration and bone ingrowth.

Science.gov (United States)

Liu, Hao; Li, Wei; Liu, Can; Tan, Jie; Wang, Hong; Hai, Bao; Cai, Hong; Leng, Hui-Jie; Liu, Zhong-Jun; Song, Chun-Li

2016-10-27

Three-dimensional porous titanium alloys printed via electron beam melting have low stiffness similar to that of cortical bone and are promising scaffolds for orthopedic applications. However, the bio-inert nature of titanium alloy is poorly compatible with bone ingrowth. We previously observed that simvastatin/poloxamer 407 thermosensitive hydrogel induces endogenous angiogenic/osteogenic growth factors and promotes angiogenesis and osteogenesis, but the mechanical properties of this hydrogel are poor. The purpose of this study was to construct 3D-printed porous titanium scaffolds (pTi scaffolds) filled with simvastatin/hydrogel and evaluate the effects of this composite on osseointegration, bone ingrowth and neovascularization using a tibial defect rabbit model. Four and eight weeks after implantation, the bone volume, bone mineral density, mineral apposition rate, and push-in maximum force of the pTi scaffolds filled with simvastatin/hydrogel were significantly higher than those without simvastatin (p bone and neovascularization (p bone ingrowth.

Preclinical study of SZ2080 material 3D microstructured scaffolds for cartilage tissue engineering made by femtosecond direct laser writing lithography

International Nuclear Information System (INIS)

Mačiulaitis, Justinas; Darinskas, Adas; Šimbelytė, Agnė; Mačiulaitis, Romaldas; Deveikytė, Milda; Rekštytė, Sima; Malinauskas, Mangirdas; Bratchikov, Maksim; Daunoras, Gintaras; Laurinavičienė, Aida; Laurinavičius, Arvydas; Gudas, Rimtautas

2015-01-01

Over the last decade DLW employing ultrafast pulsed lasers has become a well-established technique for the creation of custom-made free-form three-dimensional (3D) microscaffolds out of a variety of materials ranging from proteins to biocompatible glasses. Its potential applications for manufacturing a patient’s specific scaffold seem unlimited in terms of spatial resolution and geometry complexity. However, despite few exceptions in which live cells or primitive organisms were encapsulated into a polymer matrix, no demonstration of an in vivo study case of scaffolds generated with the use of such a method was performed. Here, we report a preclinical study of 3D artificial microstructured scaffolds out of hybrid organic-inorganic (HOI) material SZ2080 fabricated using the DLW technique. The created 2.1 × 2.1 × 0.21 mm 3 membrane constructs are tested both in vitro by growing isolated allogeneic rabbit chondrocytes (Cho) and in vivo by implanting them into rabbit organisms for one, three and six months. An ex vivo histological examination shows that certain pore geometry and the pre-growing of Cho prior to implantation significantly improves the performance of the created 3D scaffolds. The achieved biocompatibility is comparable to the commercially available collagen membranes. The successful outcome of this study supports the idea that hexagonal-pore-shaped HOI microstructured scaffolds in combination with Cho seeding may be successfully implemented for cartilage tissue engineering. (paper)

Development and characterization of a PHB-HV-based 3D scaffold for a tissue engineering and cell-therapy combinatorial approach for spinal cord injury regeneration.

Science.gov (United States)

Ribeiro-Samy, Silvina; Silva, Nuno A; Correlo, Vitor M; Fraga, Joana S; Pinto, Luísa; Teixeira-Castro, Andreia; Leite-Almeida, Hugo; Almeida, Armando; Gimble, Jeffrey M; Sousa, Nuno; Salgado, António J; Reis, Rui L

2013-11-01

Spinal cord injury (SCI) leads to devastating neurological deficits. Several tissue engineering (TE)-based approaches have been investigated for repairing this condition. Poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHB-HV) is found to be particularly attractive for TE applications due to its properties, such as biodegradability, biocompatibility, thermoplasticity and piezoelectricity. Hence, this report addresses the development and characterization of PHB-HV-based 3D scaffolds, produced by freeze-drying, aimed to SCI treatment. The obtained scaffolds reveal an anisotropic morphology with a fully interconnected network of pores. In vitro studies demonstrate a lack of cytotoxic effect of PHB-HV scaffolds. Direct contact assays also reveal their ability to support the culture of CNS-derived cells and mesenchymal-like stem cells from different sources. Finally, histocompatibility studies show that PHB-HV scaffolds are well tolerated by the host tissue, and do not negatively impact the left hindlimb locomotor function recovery. Therefore results herein presented suggest that PHB-HV scaffolds may be suitable for SCI treatment. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Preparation and Evaluation of Gelatin-Chitosan-Nanobioglass 3D Porous Scaffold for Bone Tissue Engineering

Directory of Open Access Journals (Sweden)

Kanchan Maji

2016-01-01

Full Text Available The aim of the present study was to prepare and characterize bioglass-natural biopolymer based composite scaffold and evaluate its bone regeneration ability. Bioactive glass nanoparticles (58S in the size range of 20–30 nm were synthesized using sol-gel method. Porous scaffolds with varying bioglass composition from 10 to 30 wt% in chitosan, gelatin matrix were fabricated using the method of freeze drying of its slurry at 40 wt% solids loading. Samples were cross-linked with glutaraldehyde to obtain interconnected porous 3D microstructure with improved mechanical strength. The prepared scaffolds exhibited >80% porosity with a mean pore size range between 100 and 300 microns. Scaffold containing 30 wt% bioglass (GCB 30 showed a maximum compressive strength of 2.2±0.1 MPa. Swelling and degradation studies showed that the scaffold had excellent properties of hydrophilicity and biodegradability. GCB 30 scaffold was shown to be noncytotoxic and supported mesenchymal stem cell attachment, proliferation, and differentiation as indicated by MTT assay and RUNX-2 expression. Higher cellular activity was observed in GCB 30 scaffold as compared to GCB 0 scaffold suggesting the fact that 58S bioglass nanoparticles addition into the scaffold promoted better cell adhesion, proliferation, and differentiation. Thus, the study showed that the developed composite scaffolds are potential candidates for regenerating damaged bone tissue.

2, 3-Dihydrazone cellulose: Prospective material for tissue engineering scaffolds

International Nuclear Information System (INIS)

Verma, Vipin; Verma, Poonam; Ray, Pratima; Ray, Alok R.

2008-01-01

Cellulose was oxidized by sodium metaperiodate to give rise to 2, 3-dialdehyde cellulose with 92% oxidation ratio, which was further reacted with hydrazine to form 2, 3-dihydrazone cellulose for the incorporation of NH 2 groups. Two forms of matrix, i.e. films and sponges were fabricated. The materials were characterized by FTIR spectroscopy. Scanning electron microscopy revealed its porous architecture with an average pore size of 150 μm. Swelling studies were carried out in phosphate buffer saline (PBS) at physiological pH 7.4. The contact angle of the 2, 3-dihydrazone cellulose surface was determined for assessing its hydrophilicity which came out to be 23 deg. ± 2 deg. NIH3T3 mice fibroblast cells were used for determining the cytocompatibility of the surfaces. The morphology of the cells was observed through optical inverted microscopy. The results show that 2, 3-dihydrazone cellulose can be used as scaffold material in tissue engineering

Functionalization of PCL-3D Electrospun Nanofibrous Scaffolds for Improved BMP2-Induced Bone Formation.

Science.gov (United States)

Miszuk, Jacob M; Xu, Tao; Yao, Qingqing; Fang, Fang; Childs, Josh D; Hong, Zhongkui; Tao, Jianning; Fong, Hao; Sun, Hongli

2018-03-01

Bone morphogenic protein 2 (BMP2) is a key growth factor for bone regeneration, possessing FDA approval for orthopedic applications. BMP2 is often required in supratherapeutic doses clinically, yielding adverse side effects and substantial treatment costs. Considering the crucial role of materials for BMPs delivery and cell osteogenic differentiation, we devote to engineering an innovative bone-matrix mimicking niche to improve low dose of BMP2-induced bone formation. Our previous work describes a novel technique, named thermally induced nanofiber self-agglomeration (TISA), for generating 3D electrospun nanofibrous (NF) polycaprolactone (PCL) scaffolds. TISA process could readily blend PCL with PLA, leading to increased osteogenic capabilities in vitro , however, these bio-inert synthetic polymers produced limited BMP2-induced bone formation in vivo. We therefore hypothesize that functionalization of NF 3D PCL scaffolds with bone-like hydroxyapatite (HA) and BMP2 signaling activator phenamil will provide a favorable osteogenic niche for bone formation at low doses of BMP2. Compared to PCL-3D scaffolds, PCL/HA-3D scaffolds demonstrated synergistically enhanced osteogenic differentiation capabilities of C2C12 cells with phenamil. Importantly, in vivo studies showed this synergism was able to generate significantly increased new bone in an ectopic mouse model, suggesting PCL/HA-3D scaffolds act as a favorable synthetic extracellular matrix for bone regeneration.

Mechanical, thermal and morphological characterisation of 3D porous Pennisetum purpureum/PLA biocomposites scaffold.

Science.gov (United States)

Revati, R; Abdul Majid, M S; Ridzuan, M J M; Normahira, M; Mohd Nasir, N F; Rahman Y, M N; Gibson, A G

2017-06-01

The mechanical, thermal, and morphological properties of a 3D porous Pennisetum purpureum (PP)/polylactic acid (PLA) based scaffold were investigated. In this study, a scaffold containing P. purpureum and PLA was produced using the solvent casting and particulate leaching method. P. purpureum fibre, also locally known as Napier grass, is composed of 46% cellulose, 34% hemicellulose, and 20% lignin. PLA composites with various P. purpureum contents (10%, 20%, and 30%) were prepared and subsequently characterised. The morphologies, structures and thermal behaviours of the prepared composite scaffolds were characterised using field-emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). The morphology was studied using FESEM; the scaffold possessed 70-200μm-sized pores with a high level of interconnectivity. The moisture content and mechanical properties of the developed porous scaffolds were further characterised. The P. purpureum/PLA scaffold had a greater porosity factor (99%) and compression modulus (5.25MPa) than those of the pure PLA scaffold (1.73MPa). From the results, it can be concluded that the properties of the highly porous P. purpureum/PLA scaffold developed in this study can be controlled and optimised. This can be used to facilitate the construction of implantable tissue-engineered cartilage. Copyright © 2017 Elsevier B.V. All rights reserved.

Manufacturing of calcium phosphate scaffolds by pseudomorphic transformation of gypsum

Energy Technology Data Exchange (ETDEWEB)

Araujo Batista, H. de.; Batista Cardoso, M.; Sales Vasconcelos, A.; Vinicius Lia Fook, M.; Rodriguez Barbero, M. A.; Garcia Carrodeguas, R.

2016-08-01

Carbonated hydroxyapatite (CHAp) and β-tricalcium phosphate (β-TCP) have been employed for decades as constituents of scaffolds for bone regeneration because they chemically resemble bone mineral. In this study, the feasibility to manufacture CHAp/β-TCP scaffolds by pseudomorphic transformation of casted blocks of gypsum was investigated. The transformation was carried out by immersing the precursor gypsum block in 1 M (NH{sub 4}){sub 2}HPO{sub 4}/1.33 M NH{sub 4}OH solution with liquid/solid ratio of 10 mL/g and autoclaving at 120 degree centigrade and 203 kPa (2 atm) for 3 h at least. Neither shape nor dimensions significantly changed during transformation. The composition of scaffolds treated for 3 h was 70 wt.% CHAp and 30 wt.% β-TCP, and their compressive and diametral compressive strengths were 6.5 ± 0.7 and 5.3 ±0.7 MPa, respectively. By increasing the time of treatment to 6 h, the composition of the scaffold enriched in β-TCP (60 wt.% CHAp and 40 wt.% β-TCP) but its compressive and diametral compressive strengths were not significantly affected (6.7 ± 0.9 and 5.4 ± 0.6 MPa, respectively). On the basis of the results obtained, it was concluded that this route is a good approach to the manufacturing of biphasic (CHAp/β-TCP) scaffolds from previously shaped pieces of gypsum. (Author)

Antioxidant effects of betulin on porcine chondrocyte behavior in gelatin/C6S/C4S/HA modified tricopolymer scaffold

International Nuclear Information System (INIS)

Lin, Wen-Yang; Lin, Feng-Huei; Sadhasivam, S.; Savitha, S.

2010-01-01

The antioxidant effects of betulin on porcine chondrocytes cultured in gelatin/C6S/C4S/HA modified tricopolymer scaffold for a period of 4 weeks was investigated. The porous structure of the scaffold and cell attachment was observed by scanning electron microscopy (SEM). Biochemical measures of necrosis, cell proliferation, sulfated glycosaminoglycans (sGAG) content and extracellular matrix related gene expressions were quantitatively evaluated. The cell proliferation data showed good cellular viability in tricopolymer scaffold and increased optical density for total DNA demonstrated that the cells continued to proliferate inside the scaffold. The sGAG production indicated chondrogenic differentiation. Chondrocytes treated with betulin expressed transcripts encoding type II collagen, aggrecan, and decorin. To conclude, the substantiated results supported cell proliferation, production of extracellular matrix proteins and down-regulation of matrix metalloproteases and cytokine, in betulin treated scaffolds.

Antioxidant effects of betulin on porcine chondrocyte behavior in gelatin/C6S/C4S/HA modified tricopolymer scaffold

Energy Technology Data Exchange (ETDEWEB)

Lin, Wen-Yang; Lin, Feng-Huei [Institute of Biomedical Engineering, National Taiwan University, Taipei, Taiwan (China); Sadhasivam, S., E-mail: rahulsbio@yahoo.co.in [Institute of Biomedical Engineering, National Taiwan University, Taipei, Taiwan (China); Savitha, S. [Institute of Biomedical Engineering, National Taiwan University, Taipei, Taiwan (China)

2010-05-10

The antioxidant effects of betulin on porcine chondrocytes cultured in gelatin/C6S/C4S/HA modified tricopolymer scaffold for a period of 4 weeks was investigated. The porous structure of the scaffold and cell attachment was observed by scanning electron microscopy (SEM). Biochemical measures of necrosis, cell proliferation, sulfated glycosaminoglycans (sGAG) content and extracellular matrix related gene expressions were quantitatively evaluated. The cell proliferation data showed good cellular viability in tricopolymer scaffold and increased optical density for total DNA demonstrated that the cells continued to proliferate inside the scaffold. The sGAG production indicated chondrogenic differentiation. Chondrocytes treated with betulin expressed transcripts encoding type II collagen, aggrecan, and decorin. To conclude, the substantiated results supported cell proliferation, production of extracellular matrix proteins and down-regulation of matrix metalloproteases and cytokine, in betulin treated scaffolds.

Novel mechanically competent polysaccharide scaffolds for bone tissue engineering

International Nuclear Information System (INIS)

Kumbar, S G; Toti, U S; Deng, M; James, R; Laurencin, C T; Aravamudhan, A; Harmon, M; Ramos, D M

2011-01-01

The success of the scaffold-based bone regeneration approach critically depends on the biomaterial's mechanical and biological properties. Cellulose and its derivatives are inherently associated with exceptional strength and biocompatibility due to their β-glycosidic linkage and extensive hydrogen bonding. This polymer class has a long medical history as a dialysis membrane, wound care system and pharmaceutical excipient. Recently cellulose-based scaffolds have been developed and evaluated for a variety of tissue engineering applications. In general porous polysaccharide scaffolds in spite of many merits lack the necessary mechanical competence needed for load-bearing applications. The present study reports the fabrication and characterization of three-dimensional (3D) porous sintered microsphere scaffolds based on cellulose derivatives using a solvent/non-solvent sintering approach for load-bearing applications. These 3D scaffolds exhibited a compressive modulus and strength in the mid-range of human trabecular bone and underwent degradation resulting in a weight loss of 10–15% after 24 weeks. A typical stress–strain curve for these scaffolds showed an initial elastic region and a less-stiff post-yield region similar to that of native bone. Human osteoblasts cultured on these scaffolds showed progressive growth with time and maintained expression of osteoblast phenotype markers. Further, the elevated expression of alkaline phosphatase and mineralization at early time points as compared to heat-sintered poly(lactic acid–glycolic acid) control scaffolds with identical pore properties affirmed the advantages of polysaccharides and their potential for scaffold-based bone regeneration.

Three-Dimensional Printing of Hollow-Struts-Packed Bioceramic Scaffolds for Bone Regeneration.

Science.gov (United States)

Luo, Yongxiang; Zhai, Dong; Huan, Zhiguang; Zhu, Haibo; Xia, Lunguo; Chang, Jiang; Wu, Chengtie

2015-11-04

Three-dimensional printing technologies have shown distinct advantages to create porous scaffolds with designed macropores for application in bone tissue engineering. However, until now, 3D-printed bioceramic scaffolds only possessing a single type of macropore have been reported. Generally, those scaffolds with a single type of macropore have relatively low porosity and pore surfaces, limited delivery of oxygen and nutrition to surviving cells, and new bone tissue formation in the center of the scaffolds. Therefore, in this work, we present a useful and facile method for preparing hollow-struts-packed (HSP) bioceramic scaffolds with designed macropores and multioriented hollow channels via a modified coaxial 3D printing strategy. The prepared HSP scaffolds combined high porosity and surface area with impressive mechanical strength. The unique hollow-struts structures of bioceramic scaffolds significantly improved cell attachment and proliferation and further promoted formation of new bone tissue in the center of the scaffolds, indicating that HSP ceramic scaffolds can be used for regeneration of large bone defects. In addition, the strategy can be used to prepare other HSP ceramic scaffolds, indicating a universal application for tissue engineering, mechanical engineering, catalysis, and environmental materials.

3D Printing of Aniline Tetramer-Grafted-Polyethylenimine and Pluronic F127 Composites for Electroactive Scaffolds.

Science.gov (United States)

Dong, Shi-Lei; Han, Lu; Du, Cai-Xia; Wang, Xiao-Yu; Li, Lu-Hai; Wei, Yen

2017-02-01

Electroactive hydrogel scaffolds are fabricated by the 3D-printing technique using composites of 30% Pluronic F127 and aniline tetramer-grafted-polyethylenimine (AT-PEI) copolymers with various contents from 2.5% to 10%. The synthesized AT-PEI copolymers can self-assemble into nanoparticles with the diameter of ≈50 nm and display excellent electroactivity due to AT conjugation. The copolymers are then homogeneously distributed into 30% Pluronic F127 solution by virtue of the thermosensitivity of F127, denoted as F/AT-PEI composites. Macroscopic photographs of latticed scaffolds elucidate their excellent printability of F/AT-PEI hydrogels for the 3D-printing technique. The conductivities of the printed F/AT-PEI scaffolds are all higher than 2.0 × 10 -3 S cm -1 , which are significantly improved compared with that of F127 scaffold with only 0.94 × 10 -3 S cm -1 . Thus, the F/AT-PEI scaffolds can be considered as candidates for application in electrical stimulation of tissue regeneration such as repair of muscle and cardiac nerve tissue. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Highly defined 3D printed chitosan scaffolds featuring improved cell growth.

Science.gov (United States)

Elviri, Lisa; Foresti, Ruben; Bergonzi, Carlo; Zimetti, Francesca; Marchi, Cinzia; Bianchera, Annalisa; Bernini, Franco; Silvestri, Marco; Bettini, Ruggero

2017-07-12

The augmented demand for medical devices devoted to tissue regeneration and possessing a controlled micro-architecture means there is a need for industrial scale-up in the production of hydrogels. A new 3D printing technique was applied to the automation of a freeze-gelation method for the preparation of chitosan scaffolds with controlled porosity. For this aim, a dedicated 3D printer was built in-house: a preliminary effort has been necessary to explore the printing parameter space to optimize the printing results in terms of geometry, tolerances and mechanical properties of the product. Analysed parameters included viscosity of the starting chitosan solution, which was measured with a Brookfield viscometer, and temperature of deposition, which was determined by filming the process with a cryocooled sensor thermal camera. Optimized parameters were applied to the production of scaffolds from solutions of chitosan alone or with the addition of raffinose as a viscosity modifier. Resulting hydrogels were characterized in terms of morphology and porosity. In vitro cell culture studies comparing 3D printed scaffolds with their homologous produced by solution casting evidenced an improvement in biocompatibility deriving from the production technique as well as from the solid state modification of chitosan stemming from the addition of the viscosity modifier.

Biological evaluation of human hair keratin scaffolds for skin wound repair and regeneration

International Nuclear Information System (INIS)

Xu, Songmei; Sang, Lin; Zhang, Yaping; Wang, Xiaoliang; Li, Xudong

2013-01-01

The cytocompatibility, in vivo biodegradation and wound healing of keratin biomaterials were investigated. For the purposes, three groups of keratin scaffolds were fabricated by freeze-drying reduced solutions at 2 wt.%, 4 wt.% and 8 wt.% keratins extracted from human hairs. These scaffolds exhibited evenly distributed high porous structures with pore size of 120–220 μm and the porosity > 90%. NIH3T3 cells proliferated well on these scaffolds in culture lasting up to 22 days. Confocal micrographs stained with AO visually revealed cell attachment and infiltration as well as scaffold architectural stability. In vivo animal experiments were conducted with 4 wt.% keratin scaffolds. Early degradation of subcutaneously implanted scaffolds occurred at 3 weeks in the outermost surface, in concomitant with inflammatory response. At 5 weeks, the overall porous structure of scaffolds severely deteriorated while the early inflammatory response in the outermost surface obviously subsided. A faster keratin biodegradation was observed in repairing full-thickness skin defects. Compared with the blank control, keratin scaffolds gave rise to more blood vessels at 2 weeks and better complete wound repair at 3 weeks with a thicker epidermis, less contraction and newly formed hair follicles. These preliminary results suggest that human hair keratin scaffolds are promising dermal substitutes for skin regeneration. - Highlights: ► Preparation of highly-interconnected human hair keratin scaffolds. ► Long-term cell culturing and in vivo animal experiments with keratin scaffolds. ► Biodegradation is dependent on implantation site and function ► Early vascularization and better repair in treating full-thickness skin wounds. ► A thicker epidermis, less contraction and newly formed hair follicles are observed.

Enrichment of glioma stem cell-like cells on 3D porous scaffolds composed of different extracellular matrix.

Science.gov (United States)

Wang, Xuanzhi; Dai, Xingliang; Zhang, Xinzhi; Li, Xinda; Xu, Tao; Lan, Qing

2018-04-15

Cancer stem cells (CSCs), being tumor-initiating with self-renewal capacity and heterogeneity, are most likely the cause of tumor resistance, reoccurrence and metastasis. To further investigate the role of CSCs in tumor biology, there is a need to develop an effective culture system to grow, maintain and enrich CSCs. Three-dimensional (3D) cell culture model has been widely used in tumor research and drug screening. Recently, researchers have begun to utilize 3D models to culture cancer cells for CSCs enrichment. In this study, glioma cell line was cultured with 3D porous chitosan (CS) scaffolds or chitosan-hyaluronic acid (CS-HA) scaffolds to explore the possibility of glioma stem cells (GSCs)-like cells enrichment, to study the morphology, gene expression, and in vivo tumorigenicity of 3D scaffolds cells, and to compare results to 2D controls. Results showed that glioma cells on both CS and CS-HA scaffolds could form tumor cell spheroids and increased the expression of GSCs biomarkers compared to conventional 2D monolayers. Furthermore, cells in CS-HA scaffolds had higher expression levels of epithelial-to-mesenchymal transition (EMT)-related gene. Specifically, the in vivo tumorigenicity capability of CS-HA scaffold cultured cells was greater than 2D cells or CS scaffold cultured cells. It is indicated that the chemical composition of scaffold plays an important role in the enrichment of CSCs. Our results suggest that CS-HA scaffolds have a better capability to enrich GSCs-like cells and can serve as a simple and effective way to cultivate and enrich CSCs in vitro to support the study of CSCs biology and development of novel anti-cancer therapies. Copyright © 2018 Elsevier Inc. All rights reserved.

Cold atmospheric plasma (CAP) surface nanomodified 3D printed polylactic acid (PLA) scaffolds for bone regeneration.

Science.gov (United States)

Wang, Mian; Favi, Pelagie; Cheng, Xiaoqian; Golshan, Negar H; Ziemer, Katherine S; Keidar, Michael; Webster, Thomas J

2016-12-01

Three-dimensional (3D) printing is a new fabrication method for tissue engineering which can precisely control scaffold architecture at the micron-scale. However, scaffolds not only need 3D biocompatible structures that mimic the micron structure of natural tissues, they also require mimicking of the nano-scale extracellular matrix properties of the tissue they intend to replace. In order to achieve this, the objective of the present in vitro study was to use cold atmospheric plasma (CAP) as a quick and inexpensive way to modify the nano-scale roughness and chemical composition of a 3D printed scaffold surface. Water contact angles of a normal 3D printed poly-lactic-acid (PLA) scaffold dramatically dropped after CAP treatment from 70±2° to 24±2°. In addition, the nano-scale surface roughness (Rq) of the untreated 3D PLA scaffolds drastically increased (up to 250%) after 1, 3, and 5min of CAP treatment from 1.20nm to 10.50nm, 22.90nm, and 27.60nm, respectively. X-ray photoelectron spectroscopy (XPS) analysis showed that the ratio of oxygen to carbon significantly increased after CAP treatment, which indicated that the CAP treatment of PLA not only changed nano-scale roughness but also chemistry. Both changes in hydrophilicity and nano-scale roughness demonstrated a very efficient plasma treatment, which in turn significantly promoted both osteoblast (bone forming cells) and mesenchymal stem cell attachment and proliferation. These promising results suggest that CAP surface modification may have potential applications for enhancing 3D printed PLA bone tissue engineering materials (and all 3D printed materials) in a quick and an inexpensive manner and, thus, should be further studied. Three-dimensional (3D) printing is a new fabrication method for tissue engineering which can precisely control scaffold architecture at the micron-scale. Although their success is related to their ability to exactly mimic the structure of natural tissues and control mechanical

Substituted 4-hydroxy-1,2,3-triazoles

DEFF Research Database (Denmark)

Pippione, Agnese C.; Dosio, Franco; Ducime, Alex

2015-01-01

the distal (S)-glutamic acid carboxyl group using the 4-hydroxy-1,2,3-triazole moiety is applied, to obtain two promising glutamate analogs. In the second example, a scaffold hopping approach is applied, replacing the phenolic moiety present in MDG-1-33A, a potent inhibitor of Onchocerca volvulus chitinase...

A healing method of tympanic membrane perforations using three-dimensional porous chitosan scaffolds.

Science.gov (United States)

Kim, Jangho; Kim, Seung Won; Choi, Seong Jun; Lim, Ki Taek; Lee, Jong Bin; Seonwoo, Hoon; Choung, Pill-Hoon; Park, Keehyun; Cho, Chong-Su; Choung, Yun-Hoon; Chung, Jong Hoon

2011-11-01

Both surgical tympanoplasty and paper patch grafts are frequently procedured to heal tympanic membrane (TM) perforation or chronic otitis media, despite their many disadvantages. In this study, we report a new healing method of TM perforation by using three-dimensional (3D) porous chitosan scaffolds (3D chitosan scaffolds) as an alternative method to surgical treatment or paper patch graft. Various 3D chitosan scaffolds were prepared; and the structural characteristics, mechanical property, in vitro biocompatibility, and healing effects of the 3D chitosan scaffolds as an artificial TM in in vivo animal studies were investigated. A 3D chitosan scaffold of 5 wt.% chitosan concentration showed good proliferation of TM cells in an in vitro study, as well as suitable structural characteristics and mechanical property, as compared with either 1% or 3% chitosan. In in vivo animal studies, 3D chitosan scaffold were able to migrate through the pores and surfaces of TM cells, thus leading to more effective TM regeneration than paper patch technique. Histological observations demonstrated that the regenerated TM with the 3D chitosan scaffold consisted of three (epidermal, connective tissue, and mucosal) layers and were thicker than normal TMs. The 3D chitosan scaffold technique may be an optimal healing method used in lieu of surgical tympanoplasty in certain cases to heal perforated TMs.

Biocompatibility of hydroxyapatite scaffolds processed by lithography-based additive manufacturing.

Science.gov (United States)

Tesavibul, Passakorn; Chantaweroad, Surapol; Laohaprapanon, Apinya; Channasanon, Somruethai; Uppanan, Paweena; Tanodekaew, Siriporn; Chalermkarnnon, Prasert; Sitthiseripratip, Kriskrai

2015-01-01

The fabrication of hydroxyapatite scaffolds for bone tissue engineering applications by using lithography-based additive manufacturing techniques has been introduced due to the abilities to control porous structures with suitable resolutions. In this research, the use of hydroxyapatite cellular structures, which are processed by lithography-based additive manufacturing machine, as a bone tissue engineering scaffold was investigated. The utilization of digital light processing system for additive manufacturing machine in laboratory scale was performed in order to fabricate the hydroxyapatite scaffold, of which biocompatibilities were eventually evaluated by direct contact and cell-culturing tests. In addition, the density and compressive strength of the scaffolds were also characterized. The results show that the hydroxyapatite scaffold at 77% of porosity with 91% of theoretical density and 0.36 MPa of the compressive strength are able to be processed. In comparison with a conventionally sintered hydroxyapatite, the scaffold did not present any cytotoxic signs while the viability of cells at 95.1% was reported. After 14 days of cell-culturing tests, the scaffold was able to be attached by pre-osteoblasts (MC3T3-E1) leading to cell proliferation and differentiation. The hydroxyapatite scaffold for bone tissue engineering was able to be processed by the lithography-based additive manufacturing machine while the biocompatibilities were also confirmed.

Physico-functional and mechanical properties of chitosan and calcium salts incorporated fish gelatin scaffolds.

Science.gov (United States)

Jeevithan, E; Jeya Shakila, R; Varatharajakumar, A; Jeyasekaran, G; Sukumar, D

2013-09-01

Four types of fish gelatin scaffolds viz. gelatin (G), gelatin-chitosan (GC), gelatin-calcium acetate (GCA) and gelatin-chitosan-calcium acetate (GCCA) prepared were investigated for their functional properties, biomechanical strength, microstructural changes in relation to biodegradation. GC scaffold was superior with pH 3.15 and viscosity 9.40 cP. Chitosan and calcium acetate improved tensile strength (TS) and Young's modulus (YM), but lowered elongation at break (EAB). GCCA scaffold possessed moderate TS of 19.6 MPa, EAB of 4.76% and YM of 185 MPa. Foaming ability ratio of GC scaffold was high (3.41). GCA and GCCA scaffolds remained for 4 days before complete in vitro biodegradation. GC scaffold had larger cavities (180-300 μm) that were responsible for low swelling ratios and shrinkage factor. GCCA scaffold with moderate swelling rates, mechanical, functional properties and lowered biodegradation rate were found more suitable for biomedical applications. Copyright © 2013 Elsevier B.V. All rights reserved.

Melt electrospinning of biodegradable polyurethane scaffolds

Science.gov (United States)

Karchin, Ari; Simonovsky, Felix I.; Ratner, Buddy D.; Sanders, Joan E.

2014-01-01

Electrospinning from the melt, in contrast to from solution, is an attractive tissue engineering scaffold manufacturing process as it allows for the formation of small diameter fibers while eliminating potentially cytotoxic solvents. Despite this, there is a dearth of literature on scaffold formation via melt electrospinning. This is likely due to the technical challenges related to the need for a well-controlled high temperature setup and the difficulty in developing an appropriate polymer. In this paper, a biodegradable and thermally stable polyurethane (PU) is described specifically for use in melt electrospinning. Polymer formulations of aliphatic PUs based on (CH2)4-content diisocyanates, polycaprolactone (PCL), 1,4-butanediamine and 1,4-butanediol (BD) were evaluated for utility in the melt electrospinning process. The final polymer formulation, a catalyst-purified PU based on 1,4-butane diisocyanate, PCL and BD in a 4/1/3 molar ratio with a weight-average molecular weight of about 40 kDa, yielded a nontoxic polymer that could be readily electrospun from the melt. Scaffolds electrospun from this polymer contained point bonds between fibers and mechanical properties analogous to many in vivo soft tissues. PMID:21640853

Fabrication and characterization of strontium incorporated 3-D bioactive glass scaffolds for bone tissue from biosilica

Energy Technology Data Exchange (ETDEWEB)

Özarslan, Ali Can, E-mail: alicanozarslan@gmail.com; Yücel, Sevil, E-mail: syucel@yildiz.edu.tr

2016-11-01

Bioactive glass scaffolds that contain silica are high viable biomaterials as bone supporters for bone tissue engineering due to their bioactive behaviour in simulated body fluid (SBF). In the human body, these materials help inorganic bone structure formation due to a combination of the particular ratio of elements such as silicon (Si), calcium (Ca), sodium (Na) and phosphorus (P), and the doping of strontium (Sr) into the scaffold structure increases their bioactive behaviour. In this study, bioactive glass scaffolds were produced by using rice hull ash (RHA) silica and commercial silica based bioactive glasses. The structural properties of scaffolds such as pore size, porosity and also the bioactive behaviour were investigated. The results showed that undoped and Sr-doped RHA silica-based bioactive glass scaffolds have better bioactivity than that of commercial silica based bioactive glass scaffolds. Moreover, undoped and Sr-doped RHA silica-based bioactive glass scaffolds will be able to be used instead of undoped and Sr-doped commercial silica based bioactive glass scaffolds for bone regeneration applications. Scaffolds that are produced from undoped or Sr-doped RHA silica have high potential to form new bone for bone defects in tissue engineering. - Highlights: • Production of 3-D bioactive glass scaffolds from different silica sources • The effect of biosilica from rice hull ash on the bioactive glass scaffold • Sr additive impact on the bioactivity and biodegradability properties of scaffolds.

Fabrication of a customized bone scaffold using a homemade medical 3D printer for comminuted fractures

Science.gov (United States)

Yoon, Do-Kun; Jung, Joo-Young; Shin, Han-Back; Kim, Moo-Sub; Choe, Bo-Young; Kim, Sunmi; Suh, Tae Suk; Lee, Keum Sil; Xing, Lei

2016-09-01

The purpose of this study was to show a 3D printed reconstruction model of a bone destroyed by a comminuted fracture. After a thoracic limb of a cow with a comminuted fracture was scanned by using computed tomography, a scaffold was designed by using a 3D modeling tool for its reconstruction and fabricated by using a homemade medical 3D printer. The homemade medical 3D printer was designed for medical use. In order to reconstruct the geometry of the destroyed bone, we use the geometry of a similar section (reference geometry) of normal bone in the 3D modeling process. The missing part between the destroyed ridge and the reference geometry was filled with an effective space by using a manual interpolation. Inexpensive materials and free software were used to construct the medical 3D printer system. The fabrication of the scaffold progressed according to the design of reconstructed bone by using this medical 3D printer. The material of the scaffold was biodegradable material, and could be transplanted into the human body. The fabricated scaffold was correctly inserted into the fractured bone in place of the destroyed portion, with good agreement. According to physical stress test results, the performance of printing resolution was 0.1 mm. The average geometrical error of the scaffold was below 0.3 mm. The reconstructed bone by using the fabricated scaffold was able to support the weight of the human body. No process used to obtain the result was complex or required many resources. The methods and results in this study show several possible clinical applications in fields such as orthopedics or oncology without a need to purchase high-price instruments for 3D printing.

Scaffolds of hydroxyl apatite nanoparticles disseminated in 1, 6-diisocyanatohexane-extended poly(1, 4-butylene succinate)/poly(methyl methacrylate) for bone tissue engineering

International Nuclear Information System (INIS)

Kaur, Kulwinder; Singh, K.J.; Anand, Vikas; Bhatia, Gaurav; Kaur, Raminderjit; Kaur, Manpreet; Nim, Lovedeep; Arora, Daljit Singh

2017-01-01

Poly(1, 4-butyl succinate) extended 1, 6-diisocyanatohexane (PBSu-DCH) polymers and Polymethylmethacrylate (PMMA) scaffolds decorated with nano hydroxyl apatite have been prepared and characterized for regeneration of bone in cranio-maxillofacial region. Synthesized scaffolds revealed good response in bone regeneration and excellent cell viability in comparison to commercial available glass plate, which lead to better proliferation of MG-63 cell lines. Additionally, they demonstrate high porosity and excellent water retention ability. Moreover, controlled degradation (in pH = 7.4) and sustained drug release in pH (4.5 and 7.4) are advantages of these scaffolds to serve as delivery vehicles for therapeutic drugs. Samples also provide the protection against Escherichia coli and Methicillin Resistant Staphylococcus aureus microorganisms which can be helpful for quick recovery of the patient. In-vitro inflammatory response has been assessed via adsorption of human plasma/serum proteins on the surface of the scaffolds. Results suggest that prepared scaffolds have good bone regeneration ability and provide friendly environment for the cell growth with the additional advantage of protection of the surrounding tissues from microbial infection. With all these features, it is speculated that these scaffolds will have wide utility in the area of tissue engineering and regenerative medicine. - Highlights: • Porous scaffolds have been prepared by solvent casting technique. • Scaffolds have shown good antibacterial activity against gram positive and negative microorganisms. • Synthesized scaffolds may find applications in the area of regenerative medicine.

Scaffolds of hydroxyl apatite nanoparticles disseminated in 1, 6-diisocyanatohexane-extended poly(1, 4-butylene succinate)/poly(methyl methacrylate) for bone tissue engineering

Energy Technology Data Exchange (ETDEWEB)

Kaur, Kulwinder [Department of Physics, Guru Nanak Dev University, Amritsar 143005 (India); Singh, K.J., E-mail: kanwarjitsingh@yahoo.com [Department of Physics, Guru Nanak Dev University, Amritsar 143005 (India); Anand, Vikas [Department of Physics, Guru Nanak Dev University, Amritsar 143005 (India); Bhatia, Gaurav; Kaur, Raminderjit [Department of Molecular Biology and Biochemistry, Guru Nanak Dev University, Amritsar 143005 (India); Kaur, Manpreet [Department of Human Genetics, Guru Nanak Dev University, Amritsar 143005 (India); Nim, Lovedeep; Arora, Daljit Singh [Department of Microbiology, Guru Nanak Dev University, Amritsar 143005 (India)

2017-02-01

Poly(1, 4-butyl succinate) extended 1, 6-diisocyanatohexane (PBSu-DCH) polymers and Polymethylmethacrylate (PMMA) scaffolds decorated with nano hydroxyl apatite have been prepared and characterized for regeneration of bone in cranio-maxillofacial region. Synthesized scaffolds revealed good response in bone regeneration and excellent cell viability in comparison to commercial available glass plate, which lead to better proliferation of MG-63 cell lines. Additionally, they demonstrate high porosity and excellent water retention ability. Moreover, controlled degradation (in pH = 7.4) and sustained drug release in pH (4.5 and 7.4) are advantages of these scaffolds to serve as delivery vehicles for therapeutic drugs. Samples also provide the protection against Escherichia coli and Methicillin Resistant Staphylococcus aureus microorganisms which can be helpful for quick recovery of the patient. In-vitro inflammatory response has been assessed via adsorption of human plasma/serum proteins on the surface of the scaffolds. Results suggest that prepared scaffolds have good bone regeneration ability and provide friendly environment for the cell growth with the additional advantage of protection of the surrounding tissues from microbial infection. With all these features, it is speculated that these scaffolds will have wide utility in the area of tissue engineering and regenerative medicine. - Highlights: • Porous scaffolds have been prepared by solvent casting technique. • Scaffolds have shown good antibacterial activity against gram positive and negative microorganisms. • Synthesized scaffolds may find applications in the area of regenerative medicine.

Engineering anatomically shaped vascularized bone grafts with hASCs and 3D-printed PCL scaffolds.

Science.gov (United States)

Temple, Joshua P; Hutton, Daphne L; Hung, Ben P; Huri, Pinar Yilgor; Cook, Colin A; Kondragunta, Renu; Jia, Xiaofeng; Grayson, Warren L

2014-12-01

The treatment of large craniomaxillofacial bone defects is clinically challenging due to the limited availability of transplantable autologous bone grafts and the complex geometry of the bones. The ability to regenerate new bone tissues that faithfully replicate the anatomy would revolutionize treatment options. Advances in the field of bone tissue engineering over the past few decades offer promising new treatment alternatives using biocompatible scaffold materials and autologous cells. This approach combined with recent advances in three-dimensional (3D) printing technologies may soon allow the generation of large, bioartificial bone grafts with custom, patient-specific architecture. In this study, we use a custom-built 3D printer to develop anatomically shaped polycaprolactone (PCL) scaffolds with varying internal porosities. These scaffolds are assessed for their ability to support induction of human adipose-derived stem cells (hASCs) to form vasculature and bone, two essential components of functional bone tissue. The development of functional tissues is assessed in vitro and in vivo. Finally, we demonstrate the ability to print large mandibular and maxillary bone scaffolds that replicate fine details extracted from patient's computed tomography scans. The findings of this study illustrate the capabilities and potential of 3D printed scaffolds to be used for engineering autologous, anatomically shaped, vascularized bone grafts. © 2014 Wiley Periodicals, Inc.

Breast Cancer Stem Cell Culture and Enrichment Using Poly(ε-Caprolactone Scaffolds

Directory of Open Access Journals (Sweden)

Sònia Palomeras

2016-04-01

Full Text Available The cancer stem cell (CSC population displays self-renewal capabilities, resistance to conventional therapies, and a tendency to post-treatment recurrence. Increasing knowledge about CSCs’ phenotype and functions is needed to investigate new therapeutic strategies against the CSC population. Here, poly(ε-caprolactone (PCL, a biocompatible polymer free of toxic dye, has been used to fabricate scaffolds, solid structures suitable for 3D cancer cell culture. It has been reported that scaffold cell culture enhances the CSCs population. A RepRap BCN3D+ printer and 3 mm PCL wire were used to fabricate circular scaffolds. PCL design and fabrication parameters were first determined and then optimized considering several measurable variables of the resulting scaffolds. MCF7 breast carcinoma cell line was used to assess scaffolds adequacy for 3D cell culture. To evaluate CSC enrichment, the Mammosphere Forming Index (MFI was performed in 2D and 3D MCF7 cultures. Results showed that the 60° scaffolds were more suitable for 3D culture than the 45° and 90° ones. Moreover, 3D culture experiments, in adherent and non-adherent conditions, showed a significant increase in MFI compared to 2D cultures (control. Thus, 3D cell culture with PCL scaffolds could be useful to improve cancer cell culture and enrich the CSCs population.

Soy Protein Scaffold Biomaterials for Tissue Engineering and Regenerative Medicine

Science.gov (United States)

Chien, Karen B.

Developing functional biomaterials using highly processable materials with tailorable physical and bioactive properties is an ongoing challenge in tissue engineering. Soy protein is an abundant, natural resource with potential use for regenerative medicine applications. Preliminary studies show that soy protein can be physically modified and fabricated into various biocompatible constructs. However, optimized soy protein structures for tissue regeneration (i.e. 3D porous scaffolds) have not yet been designed. Furthermore, little work has established the in vivo biocompatibility of implanted soy protein and the benefit of using soy over other proteins including FDA-approved bovine collagen. In this work, freeze-drying and 3D printing fabrication processes were developed using commercially available soy protein to create porous scaffolds that improve cell growth and infiltration compared to other soy biomaterials previously reported. Characterization of scaffold structure, porosity, and mechanical/degradation properties was performed. In addition, the behavior of human mesenchymal stem cells seeded on various designed soy scaffolds was analyzed. Biological characterization of the cell-seeded scaffolds was performed to assess feasibility for use in liver tissue regeneration. The acute and humoral response of soy scaffolds implanted in an in vivo mouse subcutaneous model was also investigated. All fabricated soy scaffolds were modified using thermal, chemical, and enzymatic crosslinking to change properties and cell growth behavior. 3D printing allowed for control of scaffold pore size and geometry. Scaffold structure, porosity, and degradation rate significantly altered the in vivo response. Freeze-dried soy scaffolds had similar biocompatibility as freeze-dried collagen scaffolds of the same protein content. However, the soy scaffolds degraded at a much faster rate, minimizing immunogenicity. Interestingly, subcutaneously implanted soy scaffolds affected blood

Improving PEEK bioactivity for craniofacial reconstruction using a 3D printed scaffold embedded with mesenchymal stem cells.

Science.gov (United States)

Roskies, Michael; Jordan, Jack O; Fang, Dongdong; Abdallah, Mohamed-Nur; Hier, Michael P; Mlynarek, Alex; Tamimi, Faleh; Tran, Simon D

2016-07-01

Polyetheretherketone (PEEK) is a bioinert thermoplastic that has been investigated for its potential use in craniofacial reconstruction; however, its use in clinical practice is limited by a poor integration with adjacent bone upon implantation. To improve the bone-implant interface, two strategies have been employed: to modify its surface or to impregnate PEEK with bioactive materials. This study attempts to combine and improve upon the two approaches by modifying the internal structure into a trabecular network and to impregnate PEEK with mesenchymal stem cells. Furthermore, we compare the newly designed PEEK scaffolds' interactions with both bone-derived (BMSC) and adipose (ADSC) stem cells. Customized PEEK scaffolds were designed to incorporate a trabecular microstructure using a computer-aided design program and then printed via selective laser sintering (SLS), a 3D-printing process with exceptional accuracy. The scaffold structure was evaluated using microCT. Scanning electron microscopy (SEM) was used to evaluate scaffold morphology with and without mesenchymal stem cells (MSCs). Adipose and bone marrow mesenchymal cells were isolated from rats and cultured on scaffolds. Cell proliferation and differentiation were assessed using alamarBlue and alkaline phosphatase assays, respectively. Cell morphology after one week of co-culturing cells with PEEK scaffolds was evaluated using SEM. SLS 3D printing fabricated scaffolds with a porosity of 36.38% ± 6.66 and density of 1.309 g/cm(2). Cell morphology resembled viable fibroblasts attaching to the surface and micropores of the scaffold. PEEK scaffolds maintained the viability of both ADSCs and BMSCs; however, ADSCs demonstrated higher osteodifferentiation than BMSCs (p PEEK scaffolds that maintain the viability of adipose and bone marrow-derived MSCs and induce the osteodifferentiation of the adipose-derived MSCs. The combination of 3D printed PEEK scaffolds with MSCs could overcome some of the limitations

1,3,5-Triazine-based analogues of purine: from isosteres to privileged scaffolds in medicinal chemistry.

Science.gov (United States)

Lim, Felicia Phei Lin; Dolzhenko, Anton V

2014-10-06

Purines can be considered as the most ubiquitous and functional N-heterocyclic compounds in nature. Structural modifications of natural purines, particularly using isosteric ring systems, have been in the focus of many drug discovery programs. Fusion of 1,3,5-triazine ring with pyrrole, pyrazole, imidazole, 1,2,3-triazole or 1,2,4-triazole results in seven bicyclic heterocyclic systems isosteric to purine. Application of the isosterism concept for the development of new compounds with therapeutic potential in areas involving purinergic regulation or purine metabolism led to significant advances in medicinal chemistry of the azolo[1,3,5]triazines. These 1,3,5-triazine-based purine-like scaffolds significantly increase level of molecular diversity and allow covering chemical space in the important areas of medicinal chemistry. Some of these azolo[1,3,5]triazine systems have become privileged scaffolds in the development of inhibitors of various kinases, phosphodiesterase, xanthine oxidase, and thymidine phosphorylase, antagonists of adenosine and corticotropin-releasing hormone receptors, anticancer and antiviral agents. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Interfacing polymeric scaffolds with primary pancreatic ductal adenocarcinoma cells to develop 3D cancer models

NARCIS (Netherlands)

Ricci, C.; Mota, C.M.; Moscato, S.; D' Alessandro, D.; Ugel, S.; Sartoris, S.; Bronte, V.; Boggi, U.; Campani, D.; Funel, N.; Moroni, Lorenzo; Danti, S.

2014-01-01

We analyzed the interactions between human primary cells from pancreatic ductal adenocarcinoma (PDAC) and polymeric scaffolds to develop 3D cancer models useful for mimicking the biology of this tumor. Three scaffold types based on two biocompatible polymeric formulations, such as poly(vinyl

An axial distribution of seeding, proliferation, and osteogenic differentiation of MC3T3-E1 cells and rat bone marrow-derived mesenchymal stem cells across a 3D Thai silk fibroin/gelatin/hydroxyapatite scaffold in a perfusion bioreactor

Energy Technology Data Exchange (ETDEWEB)

Sinlapabodin, Salita; Amornsudthiwat, Phakdee; Damrongsakkul, Siriporn; Kanokpanont, Sorada, E-mail: sorada.k@chula.ac.th

2016-01-01

In cell culture, a perfusion bioreactor provides effective transportation of nutrients, oxygen, and waste removal to and from the core of the scaffold. In addition, it provides mechanical stimuli for enhancing osteogenic differentiation. In this study, we used an axial distribution of cell numbers, alkaline phosphatase (ALP) enzyme activity, and calcium content across 4 cross-sections of 10 mm thick scaffold, made of Thai silk fibroin (SF)/gelatin (G)/hydroxyapatite (HA), as a tool to evaluate the suitable perfusion flow rate. These evaluations cover all cellular developmental phases starting from seeding, to proliferation, and later osteogenic differentiation. Mouse pre-osteoblastic MC3T3-E1 cell lines were used as a cell model during seeding and proliferation. The bioreactor seeded scaffold provided more uniform cell distribution across the scaffold compared to centrifugal and agitation seeding, while the overall number of adhered cells from bioreactor seeding was slightly lower than agitation seeding. The dynamic culture using 1 ml/min perfusion flow rate (initial shear stress of 0.1 dyn/cm{sup 2}) enabled statistically higher MC3T3-E1 proliferation, ALP activity, and calcium deposition than those observed in the static-culturing condition. However, the perfusion flow rate of 1 ml/min seemed not to be enough for enhancing ALP expression across all sections of the scaffold. Rat bone marrow derived stromal cells (rMSC) were used in the detachment test and osteogenic differentiation. It was found that perfusion flow rate of 5 ml/min caused statistically higher cell detachment than that of 1 and 3 ml/min. The perfusion flow rate of 3 ml/min gave the highest rMSC osteogenic differentiation on a SF/G/HA scaffold than other flow rates, as observed from the significantly highest number of ALP enzyme activity and the calcium content without any significant cell growth. In addition, all of these parameters were evenly distributed across all scaffold sections. - Highlights

Bioactive Scaffolds for Regeneration of Cartilage and Subchondral Bone Interface

Science.gov (United States)

Deng, Cuijun; Zhu, Huiying; Li, Jiayi; Feng, Chun; Yao, Qingqiang; Wang, Liming; Chang, Jiang; Wu, Chengtie

2018-01-01

The cartilage lesion resulting from osteoarthritis (OA) always extends into subchondral bone. It is of great importance for simultaneous regeneration of two tissues of cartilage and subchondral bone. 3D-printed Sr5(PO4)2SiO4 (SPS) bioactive ceramic scaffolds may achieve the aim of regenerating both of cartilage and subchondral bone. We hypothesized that strontium (Sr) and silicon (Si) ions released from SPS scaffolds play a crucial role in osteochondral defect reconstruction. Methods: SPS bioactive ceramic scaffolds were fabricated by a 3D-printing method. The SEM and ICPAES were used to investigate the physicochemical properties of SPS scaffolds. The proliferation and maturation of rabbit chondrocytes stimulated by SPS bioactive ceramics were measured in vitro. The stimulatory effect of SPS scaffolds for cartilage and subchondral bone regeneration was investigated in vivo. Results: SPS scaffolds significantly stimulated chondrocyte proliferation, and SPS extracts distinctly enhanced the maturation of chondrocytes and preserved chondrocytes from OA. SPS scaffolds markedly promoted the regeneration of osteochondral defects. The complex interface microstructure between cartilage and subchondral bone was obviously reconstructed. The underlying mechanism may be related to Sr and Si ions stimulating cartilage regeneration by activating HIF pathway and promoting subchondral bone reconstruction through activating Wnt pathway, as well as preserving chondrocytes from OA via inducing autophagy and inhibiting hedgehog pathway. Conclusion: Our findings suggest that SPS scaffolds can help osteochondral defect reconstruction and well reconstruct the complex interface between cartilage and subchondral bone, which represents a promising strategy for osteochondral defect regeneration. PMID:29556366

Platelet lysate embedded scaffolds for skin regeneration.

Science.gov (United States)

Sandri, Giuseppina; Bonferoni, Maria Cristina; Rossi, Silvia; Ferrari, Franca; Mori, Michela; Cervio, Marila; Riva, Federica; Liakos, Ioannis; Athanassiou, Athanassia; Saporito, Francesca; Marini, Lara; Caramella, Carla

2015-04-01

The work presents the development of acellular scaffolds extemporaneously embedded with platelet lysate (PL), as an innovative approach in the field of tissue regeneration/reparation. PL embedded scaffolds should have a tridimensional architecture to support cell migration and growth, in order to restore skin integrity. For this reason, chondroitin sulfate (CS) was associated with sodium alginate (SA) to prepare highly porous systems. The developed scaffolds were characterized for chemical stability to γ-radiation, morphology, hydration and mechanical properties. Moreover, the capability of fibroblasts and endothelial cells to populate the scaffold was evaluated by means of proliferation test 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and confocal laser scanning microscopy study. The scaffolds, not altered by sterilization, were characterized by limited swelling and high flexibility, by foam-like structure with bubbles that formed a high surface area and irregular texture suitable for cell adhesion. Cell growth and scaffold population were evident on the bubble surface, where the cells appeared anchored to the scaffold structure. Scaffold network based on CS and SA demonstrated to be an effective support to enhance and to allow fibroblasts and endothelial cells (human umbilical vein endothelial cells, HUVEC) adhesion and proliferation. In particular, it could be hypothesized that cell adhesion was facilitated by the synergic effect of PL and CS. Although further in vivo evaluation is needed, on the basis of in vitro results, PL embedded scaffolds seem promising systems for skin wound healing.

Expansion of Bone Marrow Mesenchymal Stromal Cells in Perfused 3D Ceramic Scaffolds Enhances In Vivo Bone Formation.

Science.gov (United States)

Hoch, Allison I; Duhr, Ralph; Di Maggio, Nunzia; Mehrkens, Arne; Jakob, Marcel; Wendt, David

2017-12-01

Bone marrow-derived mesenchymal stromal cells (BMSC), when expanded directly within 3D ceramic scaffolds in perfusion bioreactors, more reproducibly form bone when implanted in vivo as compared to conventional expansion on 2D polystyrene dishes/flasks. Since the bioreactor-based expansion on 3D ceramic scaffolds encompasses multiple aspects that are inherently different from expansion on 2D polystyrene, we aimed to decouple the effects of specific parameters among these two model systems. We assessed the effects of the: 1) 3D scaffold vs. 2D surface; 2) ceramic vs. polystyrene materials; and 3) BMSC niche established within the ceramic pores during in vitro culture, on subsequent in vivo bone formation. While BMSC expanded on 3D polystyrene scaffolds in the bioreactor could maintain their in vivo osteogenic potential, results were similar as BMSC expanded in monolayer on 2D polystyrene, suggesting little influence of the scaffold 3D environment. Bone formation was most reproducible when BMSC are expanded on 3D ceramic, highlighting the influence of the ceramic substrate. The presence of a pre-formed niche within the scaffold pores had negligible effects on the in vivo bone formation. The results of this study allow a greater understanding of the parameters required for perfusion bioreactor-based manufacturing of osteogenic grafts for clinical applications. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Design and synthesis of selective CDK8/19 dual inhibitors: Discovery of 4,5-dihydrothieno[3',4':3,4]benzo[1,2-d]isothiazole derivatives.

Science.gov (United States)

Ono, Koji; Banno, Hiroshi; Okaniwa, Masanori; Hirayama, Takaharu; Iwamura, Naoki; Hikichi, Yukiko; Murai, Saomi; Hasegawa, Maki; Hasegawa, Yuka; Yonemori, Kazuko; Hata, Akito; Aoyama, Kazunobu; Cary, Douglas R

2017-04-15

To develop a novel series of CDK8/19 dual inhibitors, we employed structure-based drug design using docking models based on a library compound, 4,5-dihydroimidazolo[3',4':3,4]benzo[1,2-d]isothiazole 16 bound to CDK8. We designed various [5,6,5]-fused tricyclic scaffolds bearing a carboxamide group to maintain predicted interactions with the backbone CO and NH of Ala100 in the CDK8 kinase hinge region. We found that 4,5-dihydrothieno[3',4':3,4]benzo[1,2-d]isothiazole derivative 29a showed particularly potent enzymatic inhibitory activity in both CDK8/19 (CDK8 IC 50 : 0.76nM, CDK19 IC 50 : 1.7nM). To improve the physicochemical properties and kinase selectivity of this compound, we introduced a substituted 3-pyridyloxy group into the scaffold 8-position. The resulting optimized compound 52h showed excellent in vitro potency (CDK8 IC 50 : 0.46nM, CDK19 IC 50 : 0.99nM), physicochemical properties, and kinase selectivity (only 5 kinases showed DMG activation loop. In vitro pharmacological evaluation of 52h revealed potent suppression of phosphorylated STAT1 in various cancer cells. The high oral bioavailability found for this compound enabled in vivo studies, in which we demonstrated a mechanism-based in vivo PD effect as well as tumor growth suppression in an RPMI8226 human hematopoietic and lymphoid xenograft model in mouse [T/C: -1% (2.5mg/kg, qd)]. Copyright © 2017 Elsevier Ltd. All rights reserved.

Measurement of cell motility on proton beam micromachined 3D scaffolds

International Nuclear Information System (INIS)

Zhang, F.; Sun, F.; Kan, J.A. van; Shao, P.G.; Zheng, Z.; Ge, R.W.; Watt, F.

2005-01-01

Tissue engineering is a rapidly developing and highly interdisciplinary field that applies the principles of cell biology, engineering and material science. In natural tissues, the cells are arranged in a three-dimensional (3D) matrix which provides the appropriate functional, nutritional and spatial conditions. In scaffold guided tissue engineering 3D scaffolds provide the critical function of acting as extracellular matrices onto which cells can attach, grow, and form new tissue. The main focus of this paper is to understand cell behavior on micro-grooved and ridged substrates and to study the effects of geometrical constraints on cell motility and cell function. In this study, we found that BAE (Bovine Aortic Endothelial) cells naturally align with and are guided along 3D ridges and grooves machined into polymethylmethacrylate (PMMA) substrates. Average cell speed on micro-grooves and ridges ranged from 0.015 μm/s (for 12 μm wide and 10 μm deep ridges) to 0.025 μm/s (for 20 μm wide and 10 μm deep ridges). This compares with the cell motility rate on a flat PMMA surface where the average cell speed is around 0.012 μm/s. In this work we used scaffolds which were directly written with a focused proton beam, typically 1 MeV protons with a beam spot size of 1 x 1 μm 2

Tissue engineering penoplasty with biodegradable scaffold Maxpol-T cografted autologous fibroblasts for small penis syndrome.

Science.gov (United States)

Jin, Zhe; Wu, Yi-Guang; Yuan, Yi-Ming; Peng, Jing; Gong, Yan-Qing; Li, Guang-Yong; Song, Wei-Dong; Cui, Wan-Shou; He, Xue-You; Xin, Zhong-Cheng

2011-01-01

In this study, we investigated the safety and efficacy of a poly acid-co-glycolide biodegradable scaffold (Maxpol-T) coated by autologous fibroblasts (AF) for penile girth enlargement in small penis syndrome (SPS). Eighty patients with SPS were enrolled in a clinical study at 2 medical centers; 69 patients completed the study protocol. Scrotal skin was harvested under local anesthesia, and AFs were cultured and seeded on a Maxpol-T scaffold; the cografted scaffold was implanted under the Buck's fascia of penile shaft via a circumcising incision. Patients were followed up at 1, 3, and 6 months to evaluate penile girth changes. Patient satisfaction was assessed via Visual Analogue Scale and scored on the International Index of Erectile Function-5 (IIEF-5). Mean preoperative penile girth in the flaccid and erect state was 8.18 ± 0.83 cm and 10.26 ± 1.22 cm, respectively. At the 6-month postoperative follow-up, mean penile girth in the flaccid and erect state was increased to 12.19 ± 1.27 cm and 13.18 ± 1.31 cm, respectively (P < .001 for change in both flaccid and erect state). Sixty-five patients (94.2%) reported satisfaction with the procedure. Among them, 4 cases (5.8%) were dissatisfied, 7 cases (10.1%) were satisfied, 26 cases (37.7%) were very satisfied, and 32 cases (46.4%) were extremely satisfied. All men maintained IIEF-5 scores of more than 22. Complications included prolonged subcutaneous edema in 3 patients (4.3%) and pinpoint erosion at the suture area in 3 patients (4.3%). Implantation of autologous fibroblasts seeded on a Maxpol-T collagen scaffold holds promise as a safe and novel technique for penile girth enhancement in patients with SPS.

A 3D model of ovarian cancer cell lines on peptide nanofiber scaffold to explore the cell–scaffold interaction and chemotherapeutic resistance of anticancer drugs

Directory of Open Access Journals (Sweden)

Zehong Yang

2011-02-01

Full Text Available Zehong Yang1, Xiaojun Zhao1,21Nanomedicine Laboratory, West China Hospital and Institute for Nanobiomedical Technology and Membrane Biology, Sichuan University, Chengdu, People’s Republic of China; 2Center for Biomedical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USAAbstract: RADA16-I peptide hydrogel, a type of nanofiber scaffold derived from self-assembling peptide RADA16-I, has been extensively applied to regenerative medicine and tissue repair in order to develop novel nanomedicine systems. In this study, using RADA16-I peptide hydrogel, a three-dimensional (3D cell culture model was fabricated for in vitro culture of three ovarian cancer cell lines. Firstly, the peptide nanofiber scaffold was evaluated by transmission electron microscopy and atom force microscopy. Using phase contrast microscopy, the appearance of the representative ovarian cancer cells encapsulated in RADA16-I peptide hydrogel on days 1, 3, and 7 in 24-well Petri dishes was illustrated. The cancer cell–nanofiber scaffold construct was cultured for 5 days, and the ovarian cancer cells had actively proliferative potential. The precultured ovarian cancer cells exhibited nearly similar adhesion properties and invasion potentials in vitro between RADA16-I peptide nanofiber and type I collagen, which suggested that RADA16-I peptide hydrogel had some similar characteristics to type I collagen. The precultured ovarian cancer cells had two-fold to five-fold higher anticancer drug resistance than the conventional two-dimensional Petri dish culture. So the 3D cell model on peptide nanofiber scaffold is an optimal type of cell pattern for anticancer drug screening and tumor biology.Keywords: 3D culture, anticancer drug, nanofiber scaffold, cell viability, ovarian cancer

Oxygen and nitrogen plasma etching of three-dimensional hydroxyapatite/chitosan scaffolds fabricated by additive manufacturing

Science.gov (United States)

Myung, Sung-Woon; Kim, Byung-Hoon

2016-01-01

Three-dimensional (3D) chitosan and hydroxyapatite (HAp)/chitosan (CH) scaffolds were fabricated by additive manufacturing, then their surfaces were etched with oxygen (O2) and nitrogen (N2) plasma. O2 and N2 plasma etching was performed to increase surface properties such as hydrophilicity, roughness, and surface chemistry on the scaffolds. After etching, hydroxyapatite was exposed on the surface of 3D HAp/CH scaffolds. The surface morphology and chemical properties were characterized by contact angle measurement, scanning electron microscopy, X-ray diffraction, and attenuated total reflection Fourier infrared spectroscopy. The cell viability of 3D chitosan scaffolds was examined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The differentiation of preosteoblast cells was evaluated by alkaline phosphatase assay. The cell viability was improved by O2 and N2 plasma etching of 3D chitosan scaffolds. The present fabrication process for 3D scaffolds might be applied to a potential tool for preparing biocompatible scaffolds.

A novel approach for fabricating highly tunable and fluffy bioinspired 3D poly(vinyl alcohol) (PVA) fiber scaffolds.

Science.gov (United States)

Roy, Sunanda; Kuddannaya, Shreyas; Das, Tanya; Lee, Heng Yeong; Lim, Jacob; Hu, Xiao 'Matthew'; Chee Yoon, Yue; Kim, Jaehwan

2017-06-01

The excellent biocompatibility, biodegradability and chemo-thermal stability of poly(vinyl alcohol) (PVA) have been harnessed in diverse practical applications. These properties have motivated the fabrication of high performance PVA based nanofibers with adequate control over the micro and nano-architectures and surface chemical interactions. However, the high water solubility and hydrophilicity of the PVA polymer limits the application of the electrospun PVA nanofibers in aqueous environments owing to instantaneous dissolution. In this work, we report a novel yet facile concept for fabricating extremely light, fluffy, insoluble and stable three dimensional (3D) PVA fibrous scaffolds with/without coating for multifunctional purposes. While the solubility, morphology, fiber density and mechanical properties of nanofibers could be tuned by optimizing the cross-linking conditions, the surface chemical reactivity could be readily enhanced by coating with a polydopamine (pDA) bioinspired polymer without compromising the stability and innate properties of the native PVA fiber. The 3D pDA-PVA scaffolds exhibited super dye adsorption and constructive synergistic cell-material interactions by promoting healthy adhesion and viability of the human mesenchymal stem cells (hMSCs) within 3D micro-niches. We foresee the application of tunable PVA 3D as a highly adsorbent material and a scaffold material for tissue regeneration and drug delivery with close consideration of realistic in vivo parameters.

Poly(dopamine) coating of 3D printed poly(lactic acid) scaffolds for bone tissue engineering

International Nuclear Information System (INIS)

Kao, Chia-Tze; Lin, Chi-Chang; Chen, Yi-Wen; Yeh, Chia-Hung; Fang, Hsin-Yuan; Shie, Ming-You

2015-01-01

3D printing is a versatile technique to generate large quantities of a wide variety of shapes and sizes of polymer. The aim of this study is to develop functionalized 3D printed poly(lactic acid) (PLA) scaffolds and use a mussel-inspired surface coating to regulate cell adhesion, proliferation and differentiation of human adipose-derived stem cells (hADSCs). We prepared PLA 3D scaffolds coated with polydopamine (PDA). The chemical composition and surface properties of PDA/PLA were characterized by XPS. PDA/PLA modulated hADSCs' responses in several ways. Firstly, adhesion and proliferation, and cell cycle of hADSCs cultured on PDA/PLA were significantly enhanced relative to those on PLA. In addition, the collagen I secreted from cells was increased and promoted cell attachment and cell cycle progression were depended on the PDA content. In osteogenesis assay, the ALP activity and osteocalcin of hADSCs cultured on PDA/PLA were significantly higher than seen in those cultured on pure PLA scaffolds. Moreover, hADSCs cultured on PDA/PLA showed up-regulation of the ang-1 and vWF proteins associated with angiogenic differentiation. Our results demonstrate that the bio-inspired coating synthetic PLA polymer can be used as a simple technique to render the surfaces of synthetic scaffolds active, thus enabling them to direct the specific responses of hADSCs. - Highlights: • A simple method of 3D printed poly(lactic acid) scaffold coated with PDA • Promoted proliferation of hADSCs on PDA/PLA scaffolds • Increased collagen I, cell cycle, and cell adhesion with a high PDA content • Up-regulation of angiogenic and osteogenic of hADSCs • A promising method for bioinspired surface modification on PLA using PDA

Poly(dopamine) coating of 3D printed poly(lactic acid) scaffolds for bone tissue engineering

Energy Technology Data Exchange (ETDEWEB)

Kao, Chia-Tze [School of Dentistry, Chung Shan Medical University, Taichung City, Taiwan (China); Department of Stomatology, Chung Shan Medical University Hospital, Taichung City, Taiwan (China); Lin, Chi-Chang [Department of Chemical and Materials Engineering, Tunghai University, Taichung City, Taiwan (China); Chen, Yi-Wen; Yeh, Chia-Hung [3D Printing Medical Research Center, China Medical University Hospital, Taichung City, Taiwan (China); Fang, Hsin-Yuan [3D Printing Medical Research Center, China Medical University Hospital, Taichung City, Taiwan (China); Department of Thoracic Surgery, China Medical University Hospital, Taichung City, Taiwan (China); School of Medicine, College of Medicine, College of Public Health, Taichung City, Taiwan (China); Shie, Ming-You, E-mail: eviltacasi@gmail.com [3D Printing Medical Research Center, China Medical University Hospital, Taichung City, Taiwan (China)

2015-11-01

3D printing is a versatile technique to generate large quantities of a wide variety of shapes and sizes of polymer. The aim of this study is to develop functionalized 3D printed poly(lactic acid) (PLA) scaffolds and use a mussel-inspired surface coating to regulate cell adhesion, proliferation and differentiation of human adipose-derived stem cells (hADSCs). We prepared PLA 3D scaffolds coated with polydopamine (PDA). The chemical composition and surface properties of PDA/PLA were characterized by XPS. PDA/PLA modulated hADSCs' responses in several ways. Firstly, adhesion and proliferation, and cell cycle of hADSCs cultured on PDA/PLA were significantly enhanced relative to those on PLA. In addition, the collagen I secreted from cells was increased and promoted cell attachment and cell cycle progression were depended on the PDA content. In osteogenesis assay, the ALP activity and osteocalcin of hADSCs cultured on PDA/PLA were significantly higher than seen in those cultured on pure PLA scaffolds. Moreover, hADSCs cultured on PDA/PLA showed up-regulation of the ang-1 and vWF proteins associated with angiogenic differentiation. Our results demonstrate that the bio-inspired coating synthetic PLA polymer can be used as a simple technique to render the surfaces of synthetic scaffolds active, thus enabling them to direct the specific responses of hADSCs. - Highlights: • A simple method of 3D printed poly(lactic acid) scaffold coated with PDA • Promoted proliferation of hADSCs on PDA/PLA scaffolds • Increased collagen I, cell cycle, and cell adhesion with a high PDA content • Up-regulation of angiogenic and osteogenic of hADSCs • A promising method for bioinspired surface modification on PLA using PDA.

In vitro osteoclastogenesis on textile chitosan scaffold

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C Heinemann

2010-02-01

Full Text Available Textile chitosan fibre scaffolds were evaluated in terms of interaction with osteoclast-like cells, derived from human primary monocytes. Part of the scaffolds was further modified by coating with fibrillar collagen type I in order to make the surface biocompatible. Monocytes were cultured directly on the scaffolds in the presence of macrophage colony stimulating factor (M-CSF and receptor activator of nuclear factor kappaB ligand (RANKL for up to 18 days. Confocal laser scanning microscopy (CLSM as well as scanning electron microscopy (SEM revealed the formation of multinuclear osteoclast-like cells on both the raw chitosan fibres and the collagen-coated scaffolds. The modified surface supported the osteoclastogenesis. Differentiation towards the osteoclastic lineage was confirmed by the microscopic detection of cathepsin K, tartrate resistant acid phosphatase (TRAP, acidic compartments using 3-(2,4-dinitroanillino-3’-amino-N-methyldipropylamine (DAMP, immunological detection of TRAP isoform 5b, and analysis of gene expression of the osteoclastic markers TRAP, cathepsin K, vitronectin receptor, and calcitonin receptor using reverse transcription-polymerase chain reaction (RT-PCR. The feature of the collagen-coated but also of the raw chitosan fibre scaffolds to support attachment and differentiation of human monocytes facilitates cell-induced material resorption – one main requirement for successful bone tissue engineering.

Microporous dermal-like electrospun scaffolds promote accelerated skin regeneration.

Science.gov (United States)

Bonvallet, Paul P; Culpepper, Bonnie K; Bain, Jennifer L; Schultz, Matthew J; Thomas, Steven J; Bellis, Susan L

2014-09-01

The goal of this study was to synthesize skin substitutes that blend native extracellular matrix (ECM) molecules with synthetic polymers which have favorable mechanical properties. To this end, scaffolds were electrospun from collagen I (col) and poly(ɛ-caprolactone) (PCL), and then pores were introduced mechanically to promote fibroblast infiltration, and subsequent filling of the pores with ECM. A 70:30 col/PCL ratio was determined to provide optimal support for dermal fibroblast growth, and a pore diameter, 160 μm, was identified that enabled fibroblasts to infiltrate and fill pores with native matrix molecules, including fibronectin and collagen I. Mechanical testing of 70:30 col/PCL scaffolds with 160 μm pores revealed a tensile strength of 1.4 MPa, and the scaffolds also exhibited a low rate of contraction (pores. Keratinocytes formed a stratified layer on the surface of fibroblast-remodeled scaffolds, and staining for cytokeratin 10 revealed terminally differentiated keratinocytes at the apical surface. When implanted, 70:30 col/PCL scaffolds degraded within 3-4 weeks, an optimal time frame for degradation in vivo. Finally, 70:30 col/PCL scaffolds with or without 160 μm pores were implanted into full-thickness critical-sized skin defects. Relative to nonporous scaffolds or sham wounds, scaffolds with 160 μm pores induced accelerated wound closure, and stimulated regeneration of healthy dermal tissue, evidenced by a more normal-appearing matrix architecture, blood vessel in-growth, and hair follicle development. Collectively, these results suggest that microporous electrospun scaffolds are effective substrates for skin regeneration.

The 3,7-diazabicyclo[3.3.1]nonane scaffold for subtype selective nicotinic acetylcholine receptor (nAChR) ligands. Part 1: the influence of different hydrogen bond acceptor systems on alkyl and (hetero)aryl substituents.

Science.gov (United States)

Eibl, Christoph; Tomassoli, Isabelle; Munoz, Lenka; Stokes, Clare; Papke, Roger L; Gündisch, Daniela

2013-12-01

3,7-Diazabicyclo[3.3.1]nonane is a naturally occurring scaffold interacting with nicotinic acetylcholine receptors (nAChRs). When one nitrogen of the 3,7-diazabicyclo[3.3.1]nonane scaffold was implemented in a carboxamide motif displaying a hydrogen bond acceptor (HBA) functionality, compounds with higher affinities and subtype selectivity for α4β2(∗) were obtained. The nature of the HBA system (carboxamide, sulfonamide, urea) had a strong impact on nAChR interaction. High affinity ligands for α4β2(∗) possessed small alkyl chains, small un-substituted hetero-aryl groups or para-substituted phenyl ring systems along with a carboxamide group. Electrophysiological responses of selected 3,7-diazabicyclo[3.3.1]nonane derivatives to Xenopus oocytes expressing various nAChR subtypes showed diverse activation profiles. Compounds with strongest agonistic profiles were obtained with small alkyl groups whereas a shift to partial agonism/antagonism was observed for aryl substituents. Copyright © 2013 Elsevier Ltd. All rights reserved.

Bioactive polymeric scaffolds for tissue engineering

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Scott Stratton

2016-12-01

Full Text Available A variety of engineered scaffolds have been created for tissue engineering using polymers, ceramics and their composites. Biomimicry has been adopted for majority of the three-dimensional (3D scaffold design both in terms of physicochemical properties, as well as bioactivity for superior tissue regeneration. Scaffolds fabricated via salt leaching, particle sintering, hydrogels and lithography have been successful in promoting cell growth in vitro and tissue regeneration in vivo. Scaffold systems derived from decellularization of whole organs or tissues has been popular due to their assured biocompatibility and bioactivity. Traditional scaffold fabrication techniques often failed to create intricate structures with greater resolution, not reproducible and involved multiple steps. The 3D printing technology overcome several limitations of the traditional techniques and made it easier to adopt several thermoplastics and hydrogels to create micro-nanostructured scaffolds and devices for tissue engineering and drug delivery. This review highlights scaffold fabrication methodologies with a focus on optimizing scaffold performance through the matrix pores, bioactivity and degradation rate to enable tissue regeneration. Review highlights few examples of bioactive scaffold mediated nerve, muscle, tendon/ligament and bone regeneration. Regardless of the efforts required for optimization, a shift in 3D scaffold uses from the laboratory into everyday life is expected in the near future as some of the methods discussed in this review become more streamlined.

Fabrication of uniaxially aligned 3D electrospun scaffolds for neural regeneration

Energy Technology Data Exchange (ETDEWEB)

Subramanian, Anuradha; Krishnan, Uma Maheswari; Sethuraman, Swaminathan, E-mail: swami@sastra.edu [Center for Nanotechnology and Advanced Biomaterials, SASTRA University, Thanjavur 613 401, Tamil Nadu (India)

2011-04-15

Nanofibrous scaffolds are very promising physical guidance substrates for regenerating nerves to traverse larger nerve gaps. In this study, we have attempted to develop 2D random and 3D longitudinally oriented nanofibers of poly(lactide-co-glycolide) (PLGA) by the modified electrospinning process and characterized the surface morphology, mechanical properties, porosity, degradation and wettability. The orientation of aligned fibers was optimized by varying the speed of the rotating mandrel in the electrospinning process. The mean diameter of random PLGA nanofibers was 197 {+-} 72 nm, whereas that of the aligned PLGA fiber was 187 {+-} 121 nm. The pore size of aligned PLGA nanofibers (3.5 {+-} 1.1 {mu}m) was significantly lower than their respective random nanofibers (8.0 {+-} 2.0 {mu}m) (p < 0.05). However, the percentage porosity of both scaffolds was comparable (p > 0.05). The mass loss percentage and molecular weight loss percentage due to degradation was higher in random PLGA fibers when compared to aligned PLGA after 5 weeks (p < 0.05). The tensile strength and Young's modulus of random PLGA fibers were significantly higher than those of the aligned PLGA nanofibers (p < 0.05). Both random and longitudinally aligned scaffolds were used for the in vitro culture of Schwann cells. Morphology and cell proliferation results demonstrated that the aligned fibers assist the direction of Schwann cells and a better proliferation rate than their random fibers. The results confirmed that aligned nanofibers have better deformability, slow degradation, comparable porosity and orientation cues than random nanofibers. Hence the longitudinally aligned nanofibers may be ideal scaffolds for nerve regeneration.

Biological effects of functionalizing copolymer scaffolds with nanodiamond particles.

Science.gov (United States)

Xing, Zhe; Pedersen, Torbjorn O; Wu, Xujun; Xue, Ying; Sun, Yang; Finne-Wistrand, Anna; Kloss, Frank R; Waag, Thilo; Krueger, Anke; Steinmüller-Nethl, Doris; Mustafa, Kamal

2013-08-01

Significant evidence has indicated that poly(L-lactide)-co-(ɛ-caprolactone) [(poly(LLA-co-CL)] scaffolds could be one of the suitable candidates for bone tissue engineering. Oxygen-terminated nanodiamond particles (n-DP) were combined with poly(LLA-co-CL) and revealed to be positive for cell growth. In this study, we evaluated the influence of poly(LLA-co-CL) scaffolds modified by n-DP on attachment, proliferation, differentiation of bone marrow stromal cells (BMSCs) in vitro, and on bone formation using a sheep calvarial defect model. BMSCs were seeded on either poly(LLA-co-CL)- or n-DP-coated scaffolds and incubated for 1 h. Scanning electron microscopy (SEM) and fluorescence microscopy were used in addition to protein and DNA measurements to evaluate cellular attachment on the scaffolds. To determine the effect of n-DP on proliferation of BMSCs, cell/scaffold constructs were harvested after 3 days and evaluated by Bicinchoninic Acid (BCA) protein assay and SEM. In addition, the osteogenic differentiation of cells grown for 2 weeks on the various scaffolds and in a dynamic culture condition was evaluated by real-time RT-PCR. Unmodified and modified scaffolds were implanted into the calvaria of six-year-old sheep. The expression of collagen type I (COL I) and bone morphogenetic protein-2 (BMP-2) after 4 weeks as well as the formation of new bone after 12 and 24 weeks were analyzed by immunohistochemistry and histology. Scaffolds modified with n-DP supported increased cell attachment and the mRNA expression of osteopontin (OPN), bone sialoprotein (BSP), and BMP-2 were significantly increased after 2 weeks of culture. The BMSCs had spread well on the various scaffolds investigated after 3 days in the study with no significant difference in cell proliferation. Furthermore, the in vivo data revealed more positive staining of COL I and BMP-2 in relation to the n-DP-coated scaffolds after 4 weeks and presented more bone formation after 12 and 24 weeks. n

Methods of improving mechanical and biomedical properties of Ca-Si-based ceramics and scaffolds.

Science.gov (United States)

Wu, Chengtie

2009-05-01

CaSiO3 ceramics and porous scaffolds are regarded as potential materials for bone tissue regeneration owing to their excellent bioactivity. However, their low mechanical strength and high dissolution limit their further biomedical application. In this report, we introduce three methods to improve the mechanical and biomedical properties of CaSiO3 ceramics and scaffolds. Positive ions and polymer modification are two promising ways to improve the mechanical and biomedical properties of CaSiO3 ceramics and scaffolds for bone tissue regeneration.

Gas anti-solvent precipitation assisted salt leaching for generation of micro- and nano-porous wall in bio-polymeric 3D scaffolds.

Science.gov (United States)

Flaibani, Marina; Elvassore, Nicola

2012-08-01

The mass transport through biocompatible and biodegradable polymeric 3D porous scaffolds may be depleted by non-porous impermeable internal walls. As consequence the concentration of metabolites and growth factors within the scaffold may be heterogeneous leading to different cell fate depending on spatial cell location, and in some cases it may compromise cell survival. In this work, we fabricated polymeric scaffolds with micro- and nano-scale porosity by developing a new technique that couples two conventional scaffold production methods: solvent casting-salt leaching and gas antisolvent precipitation. 10-15 w/w solutions of a hyaluronic benzyl esters (HYAFF11) and poly-(lactic acid) (PLA) were used to fill packed beds of 0.177-0.425 mm NaCl crystals. The polymer precipitation in micro and nano-porous structures between the salt crystals was induced by high-pressure gas, then its flushing extracted the residual solvent. The salt was removed by water-wash. Morphological analysis by scanning electron microscopy showed a uniform porosity (~70%) and a high interconnectivity between porous. The polymeric walls were porous themselves counting for 30% of the total porosity. This wall porosity did not lead to a remarkable change in compressive modulus, deformation, and rupture pressure. Scaffold biocompatibility was tested with murine muscle cell line C2C12 for 4 and 7 days. Viability analysis and histology showed that micro- and nano-porous scaffolds are biocompatible and suitable for 3D cell culture promoting cell adhesion on the polymeric wall and allowing their proliferation in layers. Micro- and nano-scale porosities enhance cell migration and growth in the inner part of the scaffold. Copyright © 2012 Elsevier B.V. All rights reserved.

Dose-related effects of sericin on preadipocyte behavior within collagen/sericin hybrid scaffolds

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Valentina Mitran

2015-04-01

Full Text Available This paper aims at demonstrating the biocompatibility of recently developed 3D hydrogel scaffolds containing the same amount of collagen (COLL and variable concentrations of sericin (SS in order to find the most suitable formula for adipose tissue engineering (ATE applications. These scaffolds were obtained by COLL crosslinking with glutaraldehyde followed by freeze-drying and, subsequently, seeded with 3T3-L1 preadipocytes. Scanning electron microscopy studies revealed the scaffolds׳ architecture and cellular colonization. Also, in vitro biocompatibility of the developed scaffolds was evaluated by LDH and MTT assays and Live/Dead analysis of 3T3-L1 preadipocyte populating these 3D matrices. The best results in terms of cell survival and proliferation status were obtained in the case of the hybrid COLL scaffold containing 40% SS (COLL–SS4. Furthermore, the biological performance of the analyzed COLL-based hydrogels at 5- and 8- days post-seeding was found to decrease as follows: COLL–SS4>COLL–SS2>COLL>COLL–SS6. Consequently, our study highlights that hybrid scaffolds obtained by the addition of variable concentrations of SS to a constant COLL composition positively influences the behavior of 3T3-L1 cells with the exception of the COLL–SS6 matrix (60% SS. Altogether, the data obtained recommend SS as a component of COLL-based hydrogels providing them with features that may be useful in ATE applications.

Magnetic responsive hydroxyapatite composite scaffolds construction for bone defect reparation

Directory of Open Access Journals (Sweden)

Zeng XB

2012-07-01

Full Text Available Xiao Bo Zeng, Hao Hu, Li Qin Xie, Fang Lan, Wen Jiang, Yao Wu, Zhong Wei GuNational Engineering Research Center for Biomaterials, Sichuan University, Chengdu, Sichuan, People's Republic of ChinaIntroduction: In recent years, interest in magnetic biomimetic scaffolds for tissue engineering has increased considerably. A type of magnetic scaffold composed of magnetic nanoparticles (MNPs and hydroxyapatite (HA for bone repair has been developed by our research group.Aim and methods: In this study, to investigate the influence of the MNP content (in the scaffolds on the cell behaviors and the interactions between the magnetic scaffold and the exterior magnetic field, a series of MNP-HA magnetic scaffolds with different MNP contents (from 0.2% to 2% were fabricated by immersing HA scaffold into MNP colloid. ROS 17/2.8 and MC3T3-E1 cells were cultured on the scaffolds in vitro, with and without an exterior magnetic field, respectively. The cell adhesion, proliferation and differentiation were evaluated via scanning electron microscopy; confocal laser scanning microscopy; and 3-(4,5-Dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT, alkaline phosphatase, and bone gla protein activity tests.Results: The results demonstrated the positive influence of the magnetic scaffolds on cell adhesion, proliferation, and differentiation. Further, a higher amount of MNPs on the magnetic scaffolds led to more significant stimulation.Conclusion: The magnetic scaffold can respond to the exterior magnetic field and engender some synergistic effect to intensify the stimulating effect of a magnetic field to the proliferation and differentiation of cells.Keywords: magnetic therapy, magnetic nanoparticles, bone repair, magnetic responsive

Gas anti-solvent precipitation assisted salt leaching for generation of micro- and nano-porous wall in bio-polymeric 3D scaffolds

Energy Technology Data Exchange (ETDEWEB)

Flaibani, Marina; Elvassore, Nicola, E-mail: nicola.elvassore@unipd.it

2012-08-01

The mass transport through biocompatible and biodegradable polymeric 3D porous scaffolds may be depleted by non-porous impermeable internal walls. As consequence the concentration of metabolites and growth factors within the scaffold may be heterogeneous leading to different cell fate depending on spatial cell location, and in some cases it may compromise cell survival. In this work, we fabricated polymeric scaffolds with micro- and nano-scale porosity by developing a new technique that couples two conventional scaffold production methods: solvent casting-salt leaching and gas antisolvent precipitation. 10-15 w/w solutions of a hyaluronic benzyl esters (HYAFF11) and poly-(lactic acid) (PLA) were used to fill packed beds of 0.177-0.425 mm NaCl crystals. The polymer precipitation in micro and nano-porous structures between the salt crystals was induced by high-pressure gas, then its flushing extracted the residual solvent. The salt was removed by water-wash. Morphological analysis by scanning electron microscopy showed a uniform porosity ({approx} 70%) and a high interconnectivity between porous. The polymeric walls were porous themselves counting for 30% of the total porosity. This wall porosity did not lead to a remarkable change in compressive modulus, deformation, and rupture pressure. Scaffold biocompatibility was tested with murine muscle cell line C2C12 for 4 and 7 days. Viability analysis and histology showed that micro- and nano-porous scaffolds are biocompatible and suitable for 3D cell culture promoting cell adhesion on the polymeric wall and allowing their proliferation in layers. Micro- and nano-scale porosities enhance cell migration and growth in the inner part of the scaffold. - Highlights: Black-Right-Pointing-Pointer Gas anti-solvent precipitation and salt leaching for scaffold fabrication. Black-Right-Pointing-Pointer Hyaluronic benzyl esters (HYAFF11) and poly-(lactic acid) (PLA) sponges. Black-Right-Pointing-Pointer Gas anti-solvent precipitation

Gas anti-solvent precipitation assisted salt leaching for generation of micro- and nano-porous wall in bio-polymeric 3D scaffolds

International Nuclear Information System (INIS)

Flaibani, Marina; Elvassore, Nicola

2012-01-01

The mass transport through biocompatible and biodegradable polymeric 3D porous scaffolds may be depleted by non-porous impermeable internal walls. As consequence the concentration of metabolites and growth factors within the scaffold may be heterogeneous leading to different cell fate depending on spatial cell location, and in some cases it may compromise cell survival. In this work, we fabricated polymeric scaffolds with micro- and nano-scale porosity by developing a new technique that couples two conventional scaffold production methods: solvent casting-salt leaching and gas antisolvent precipitation. 10–15 w/w solutions of a hyaluronic benzyl esters (HYAFF11) and poly-(lactic acid) (PLA) were used to fill packed beds of 0.177–0.425 mm NaCl crystals. The polymer precipitation in micro and nano-porous structures between the salt crystals was induced by high-pressure gas, then its flushing extracted the residual solvent. The salt was removed by water-wash. Morphological analysis by scanning electron microscopy showed a uniform porosity (∼ 70%) and a high interconnectivity between porous. The polymeric walls were porous themselves counting for 30% of the total porosity. This wall porosity did not lead to a remarkable change in compressive modulus, deformation, and rupture pressure. Scaffold biocompatibility was tested with murine muscle cell line C2C12 for 4 and 7 days. Viability analysis and histology showed that micro- and nano-porous scaffolds are biocompatible and suitable for 3D cell culture promoting cell adhesion on the polymeric wall and allowing their proliferation in layers. Micro- and nano-scale porosities enhance cell migration and growth in the inner part of the scaffold. - Highlights: ► Gas anti-solvent precipitation and salt leaching for scaffold fabrication. ► Hyaluronic benzyl esters (HYAFF11) and poly-(lactic acid) (PLA) sponges. ► Gas anti-solvent precipitation induces nano-porous structures. ► Scaffolds are biocompatible and

Privileged scaffolds or promiscuous binders: a glance of pyrrolo[2,1-f][1,2,4]triazines and related bridgehead nitrogen heterocycles in medicinal chemistry.

Science.gov (United States)

Song, Yu'ning; Zhan, Peng; Zhang, Qingzhu; Liu, Xinyong

2013-01-01

Pyrrolo[2,1-f][1,2,4]triazine template, a unique bridgehead nitrogen heterocycle, certainly deserves the title of "privileged scaffold" in the drug discovery field because of the versatility and potential to yield derivatives with a wide range of biological activities, such as anti-anaplastic lymphoma kinase (ALK), Janus kinase 2 (JAK2), VEGFR-2, EGFR and/or HER2, Met kinase, p38α mitogen-activated protein (MAP) kinase and insulin-like growth factor receptor (IGF-1R) kinase activities, etc. These different biological properties of pyrrolo[2,1-f][1,2,4]triazine derivatives have motivated new studies in searching for novel derivatives with improved activity and also other applications in pharmaceutical field. However, no systematic review is available in the literature on the pyrrolo[2,1- f][1,2,4]triazine derivatives concerning the design of potent drug-like compounds. Owing to the importance of this heterocyclic system, the present paper is an attempt to the pharmacological activities, structural modifications and the structure-activity relationship (SAR) reported for bridgehead nitrogen heterocycles in the current literature, making an effort to highlight the importance and therapeutic potentials of the pyrrolo[2,1-f][1,2,4]triazine scaffold and its bridgehead nitrogen bioisosters as heterocyclic privileged medicinal scaffolds.

Cancer Cell Migration within 3D Layer-By-Layer Microfabricated Photocrosslinked PEG Scaffolds with Tunable Stiffness

OpenAIRE

Soman, Pranav; Kelber, Jonathan A.; Lee, Jin Woo; Wright, Tracy; Vecchio, Kenneth S.; Klemke, Richard L.; Chen, Shaochen

2012-01-01

Our current understanding of 3-dimensional (3D) cell migration is primarily based on results from fibrous scaffolds with randomly organized internal architecture. Manipulations that change the stiffness of these 3D scaffolds often alter other matrix parameters that can modulate cell motility independently or synergistically, making observations less predictive of how cells behave when migrating in 3D. In order to decouple microstructural influences and stiffness effects, we have designed and ...

In vitro cytocompatibility evaluation of chitosan/graphene oxide 3D scaffold composites designed for bone tissue engineering.

Science.gov (United States)

Dinescu, Sorina; Ionita, Mariana; Pandele, Andreea Madalina; Galateanu, Bianca; Iovu, Horia; Ardelean, Aurel; Costache, Marieta; Hermenean, Anca

2014-01-01

Extensively studied nowadays, graphene oxide (GO) has a benefic effect on cell proliferation and differentiation, thus holding promise for bone tissue engineering (BTE) approaches. The aim of this study was not only to design a chitosan 3D scaffold improved with GO for optimal BTE, but also to analyze its physicochemical properties and to evaluate its cytocompatibility and ability to support cell metabolic activity and proliferation. Overall results show that the addition of GO in the scaffold's composition improved mechanical properties and pore formation and enhanced the bioactivity of the scaffold material for tissue engineering. The new developed CHT/GO 3 wt% scaffold could be a potential candidate for further in vitro and in vivo osteogenesis studies and BTE approaches.

Strontium eluting graphene hybrid nanoparticles augment osteogenesis in a 3D tissue scaffold

Science.gov (United States)

Kumar, Sachin; Chatterjee, Kaushik

2015-01-01

particles. Thermal gravimetric analysis further confirmed the composition of the hybrid particles as 22 wt% of strontium. Macroporous tissue scaffolds were prepared by incorporating RGO_Sr particles in poly(ε-caprolactone) (PCL). The PCL/RGO_Sr scaffolds were found to elute strontium ions in aqueous medium. Osteoblast proliferation and differentiation was significantly higher in the PCL scaffolds containing the RGO_Sr particles in contrast to neat PCL and PCL/RGO scaffolds. The increased biological activity can be attributed to the release of strontium ions from the hybrid nanoparticles. This study demonstrates that composites prepared using hybrid nanoparticles that elute strontium ions can be used to prepare multifunctional scaffolds with good mechanical and osteoinductive properties. These findings have important implications for designing the next generation of biomaterials for use in tissue regeneration. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr05060f

Strontium hydroxyapatite/chitosan nanohybrid scaffolds with enhanced osteoinductivity for bone tissue engineering

International Nuclear Information System (INIS)

Lei, Yong; Xu, Zhengliang; Ke, Qinfei; Yin, Wenjing; Chen, Yixuan; Zhang, Changqing; Guo, Yaping

2017-01-01

For the clinical application of bone tissue engineering with the combination of biomaterials and mesenchymal stem cells (MSCs), bone scaffolds should possess excellent biocompatibility and osteoinductivity to accelerate the repair of bone defects. Herein, strontium hydroxyapatite [SrHAP, Ca 10−x Sr x (PO 4 ) 6 (OH) 2 ]/chitosan (CS) nanohybrid scaffolds were fabricated by a freeze-drying method. The SrHAP nanocrystals with the different x values of 0, 1, 5 and 10 are abbreviated to HAP, Sr1HAP, Sr5HAP and Sr10HAP, respectively. With increasing x values from 0 to 10, the crystal cell volumes and axial lengths of SrHAP become gradually large because of the greater ion radius of Sr 2+ than Ca 2+ , while the crystal sizes of SrHAP decrease from 70.4 nm to 46.7 nm. The SrHAP/CS nanohybrid scaffolds exhibits three-dimensional (3D) interconnected macropores with pore sizes of 100–400 μm, and the SrHAP nanocrystals are uniformly dispersed within the scaffolds. In vitro cell experiments reveal that all the HAP/CS, Sr1HAP/CS, Sr5HAP/CS and Sr10HAP/CS nanohybrid scaffolds possess excellent cytocompatibility with the favorable adhesion, spreading and proliferation of human bone marrow mesenchymal stem cells (hBMSCs). The Sr5HAP nanocrystals in the scaffolds do not affect the adhesion, spreading of hBMSCs, but they contribute remarkably to cell proliferation and osteogenic differentiation. As compared with the HAP/CS nanohybrid scaffold, the released Sr 2+ ions from the SrHAP/CS nanohybrid scaffolds enhance alkaline phosphatase (ALP) activity, extracellular matrix (ECM) mineralization and osteogenic-related COL-1 and ALP expression levels. Especially, the Sr5HAP/CS nanohybrid scaffolds exhibit the best osteoinductivity among four groups because of the synergetic effect between Ca 2+ and Sr 2+ ions. Hence, the Sr5HAP/CS nanohybrid scaffolds with excellent cytocompatibility and osteogenic property have promising application for bone tissue engineering. - Highlights: • We

Fabrication of electrospun HPGL scaffolds via glycidyl methacrylate cross-linker: Morphology, mechanical and biological properties

Energy Technology Data Exchange (ETDEWEB)

Baratéla, Fernando José Costa; Zazuco Higa, Olga [Biotechnology Center, Institute of Energy and Nuclear Research (IPEN), Av. Professor Lineu Prestes 2242, 05508-000 São Paulo, SP (Brazil); Duarte dos Passos, Esdras [PostGraduate Program in Materials for Engineering, Federal University of Itajubá (UNIFEI), Av. BPS 1303, 37500-903 Itajubá, MG (Brazil); Alencar de Queiroz, Alvaro Antonio, E-mail: alencar@unifei.edu.br [Physics and Chemistry Institute (IFQ), Federal University of Itajubá (UNIFEI), Av. BPS 1303, 37500-903 Itajubá, MG (Brazil); High Voltage Laboratory (LAT-EFEI), Federal University of Itajubá (UNIFEI), Av. BPS 1303, 37500-903 Itajubá, MG (Brazil)

2017-04-01

Electrospinning is a suitable method to produce scaffolds composed of nanoscale to microscale fibers, which are comparable to the extracellular matrix (ECM). Hyperbranched polyglycerol (HPGL) is a highly biocompatible polyether polyol potentially useful for the design of fibrous scaffolds mimicking the ECM architecture. However, scaffolds developed from HPGL have poor mechanical properties and morphological stability in the aqueous environments required for tissue engineering applications. This work reports the production of stable electrospun HPGL scaffolds (EHPGLS) using glycidyl methacrylate (GMA) as cross-linker to enhance the water stability and mechanical property of electrospun HPGL. The diameter and morphology of the produced EHPGLS were analyzed by scanning electron microscopy (SEM). It was observed that electrical fields in the range of 0.2 kV·cm{sup −1} to 1.0 kV·cm{sup −1} decrease the average fiber diameter of EHPGLS. The increase in porosity of EHPGLS with GMA concentration indicates the in situ formation of a heterogeneous structure resultant from the phase separation during crosslinking of HPGL by GMA. EHPGLS containing 20% (w/w) GMA concentration possessed highest tensile strength (295.4 ± 11.32 kPa), which is approximately 58 times higher than that of non-crosslinked EHPGLS (5.1 ± 2.12 kPa). The MTS cell viability results showed that the EHPGLS have no significant cytotoxicity effect on Chinese hamster ovary (CHO-K1) cells. Scanning electron microscopy (SEM) indicates that the cultured BALB/3T3 fibroblasts cells were able to keep contact each other's, thus forming a homogeneous monolayer on the internal surface of the EHPGLS. - Highlights: • A hyperbranched polyglycerol (HPGL) scaffold with elastic modulus of 295.4 ± 11.32 kPa was developed for soft tissue repair. • HPGL scaffold was prepared by electrospinning method. • The porosity of HPGL scaffolds can be tuned by selecting the degree of GMA in HPGL. • Electrospun HPGL

Impact of Particle Size of Ceramic Granule Blends on Mechanical Strength and Porosity of 3D Printed Scaffolds

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Sebastian Spath

2015-07-01

Full Text Available 3D printing is a promising method for the fabrication of scaffolds in the field of bone tissue engineering. To date, the mechanical strength of 3D printed ceramic scaffolds is not sufficient for a variety of applications in the reconstructive surgery. Mechanical strength is directly in relation with the porosity of the 3D printed scaffolds. The porosity is directly influenced by particle size and particle-size distribution of the raw material. To investigate this impact, a hydroxyapatite granule blend with a wide particle size distribution was fractioned by sieving. The specific fractions and bimodal mixtures of the sieved granule blend were used to 3D print specimens. It has been shown that an optimized arrangement of fractions with large and small particles can provide 3D printed specimens with good mechanical strength due to a higher packing density. An increase of mechanical strength can possibly expand the application area of 3D printed hydroxyapatite scaffolds.

PEDOT:PSS-Containing Nanohydroxyapatite/Chitosan Conductive Bionanocomposite Scaffold: Fabrication and Evaluation

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Alireza Lari

2016-01-01

Full Text Available Conductive poly(3,4-ethylenedioxythiophene-poly(4-styrene sulfonate (PEDOT:PSS was incorporated into nanohydroxyapatite/chitosan (nHA/CS composite scaffolds through a freezing and lyophilization technique. The bionanocomposite conductive scaffold was then characterized using several techniques. A scanning electron microscope image showed that the nHA and PEDOT:PSS were dispersed homogeneously in the chitosan matrix, which was also confirmed by energy-dispersive X-ray (EDX analysis. The conductive properties were measured using a digital multimeter. The weight loss and water-uptake properties of the bionanocomposite scaffolds were studied in vitro. An in vitro cell cytotoxicity test was carried out using mouse fibroblast (L929 cells cultured onto the scaffolds. Using a freezing and lyophilization technique, it was possible to fabricate three-dimensional, highly porous, and interconnected PEDOT:PSS/nHA/CS scaffolds with good handling properties. The porosity was 74% and the scaffold’s conductivity was 9.72±0.78 μS. The surface roughness was increased with the incorporation of nHA and PEDOT:PSS into the CS scaffold. The compressive mechanical properties increased significantly with the incorporation of nHA but did not change significantly with the incorporation of PEDOT:PSS. The PEDOT:PSS-containing nHA/CS scaffold exhibited significantly higher cell attachment. The PEDOT:PSS/nHA/CS scaffold could be a potential bionanocomposite conductive scaffold for tissue engineering.

Tissue-engineered bone with 3-dimensionally printed β-tricalcium phosphate and polycaprolactone scaffolds and early implantation: an in vivo pilot study in a porcine mandible model.

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Konopnicki, Sandra; Sharaf, Basel; Resnick, Cory; Patenaude, Adam; Pogal-Sussman, Tracy; Hwang, Kyung-Gyun; Abukawa, Harutsugi; Troulis, Maria J

2015-05-01

Deep bone penetration into implanted scaffolds remains a challenge in tissue engineering. The purpose of this study was to evaluate bone penetration depth within 3-dimensionally (3D) printed β-tricalcium phosphate (β-TCP) and polycaprolactone (PCL) scaffolds, seeded with porcine bone marrow progenitor cells (pBMPCs), and implanted early in vivo. Scaffolds were 3D printed with 50% β-TCP and 50% PCL. The pBMPCs were harvested, isolated, expanded, and differentiated into osteoblasts. Cells were seeded into the scaffolds and constructs were incubated in a rotational oxygen-permeable bioreactor system for 14 days. Six 2- × 2-cm defects were created in each mandible (N = 2 minipigs). In total, 6 constructs were placed within defects and 6 defects were used as controls (unseeded scaffolds, n = 3; empty defects, n = 3). Eight weeks after surgery, specimens were harvested and analyzed by hematoxylin and eosin (H&E), 4',6-diamidino-2-phenylindole (DAPI), and CD31 staining. Analysis included cell counts, bone penetration, and angiogenesis at the center of the specimens. All specimens (N = 12) showed bone formation similar to native bone at the periphery. Of 6 constructs, 4 exhibited bone formation in the center. Histomorphometric analysis of the H&E-stained sections showed an average of 22.1% of bone in the center of the constructs group compared with 1.87% in the unseeded scaffolds (P bone in the center, showed massive cell penetration depth by DAPI staining, with an average of 2,109 cells/0.57 mm(2) in the center compared with 1,114 cells/0.57 mm(2) in the controls (P printed β-TCP and PCL scaffolds seeded with pBMPCs and implanted early into porcine mandibular defects display good bone penetration depth. Further study with a larger sample and larger bone defects should be performed before human applications. Copyright © 2015 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Platelet lysate 3D scaffold supports mesenchymal stem cell chondrogenesis: an improved approach in cartilage tissue engineering.

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Moroz, Andrei; Bittencourt, Renata Aparecida Camargo; Almeida, Renan Padron; Felisbino, Sérgio Luis; Deffune, Elenice

2013-01-01

Articular lesions are still a major challenge in orthopedics because of cartilage's poor healing properties. A major improvement in therapeutics was the development of autologous chondrocytes implantation (ACI), a biotechnology-derived technique that delivers healthy autologous chondrocytes after in vitro expansion. To obtain cartilage-like tissue, 3D scaffolds are essential to maintain chondrocyte differentiated status. Currently, bioactive 3D scaffolds are promising as they can deliver growth factors, cytokines, and hormones to the cells, giving them a boost to attach, proliferate, induce protein synthesis, and differentiate. Using mesenchymal stem cells (MSCs) differentiated into chondrocytes, one can avoid cartilage harvesting. Thus, we investigated the potential use of a platelet-lysate-based 3D bioactive scaffold to support chondrogenic differentiation and maintenance of MSCs. The MSCs from adult rabbit bone marrow (n = 5) were cultivated and characterized using three antibodies by flow cytometry. MSCs (1 × 10(5)) were than encapsulated inside 60 µl of a rabbit platelet-lysate clot scaffold and maintained in Dulbecco's Modified Eagle Medium Nutrient Mixture F-12 supplemented with chondrogenic inductors. After 21 days, the MSCs-seeded scaffolds were processed for histological analysis and stained with toluidine blue. This scaffold was able to maintain round-shaped cells, typical chondrocyte metachromatic extracellular matrix deposition, and isogenous group formation. Cells accumulated inside lacunae and cytoplasm lipid droplets were other observed typical chondrocyte features. In conclusion, the usage of a platelet-lysate bioactive scaffold, associated with a suitable chondrogenic culture medium, supports MSCs chondrogenesis. As such, it offers an alternative tool for cartilage engineering research and ACI.

Surface modification of 3D-printed porous scaffolds via mussel-inspired polydopamine and effective immobilization of rhBMP-2 to promote osteogenic differentiation for bone tissue engineering.

Science.gov (United States)

Lee, Sang Jin; Lee, Donghyun; Yoon, Taek Rim; Kim, Hyung Keun; Jo, Ha Hyeon; Park, Ji Sun; Lee, Jun Hee; Kim, Wan Doo; Kwon, Il Keun; Park, Su A

2016-08-01

For tissue engineering, a bio-porous scaffold which is applied to bone-tissue regeneration should provide the hydrophilicity for cell attachment as well as provide for the capability to bind a bioactive molecule such as a growth factor in order to improve cell differentiation. In this work, we prepared a three-dimensional (3D) printed polycaprolactone scaffold (PCLS) grafted with recombinant human bone morphogenic protein-2 (rhBMP2) attached via polydopamine (DOPA) chemistry. The DOPA coated PCL scaffold was characterized by contact angle, water uptake, and X-ray photoelectron spectroscopy (XPS) in order to certify that the surface was successfully coated with DOPA. In order to test the loading and release of rhBMP2, we examined the release rate for 28days. For the In vitro cell study, pre-osteoblast MC3T3-E1 cells were seeded onto PCL scaffolds (PCLSs), DOPA coated PCL scaffold (PCLSD), and scaffolds with varying concentrations of rhBMP2 grafted onto the PCLSD 100 and PCLSD 500 (100 and 500ng/ml loaded), respectively. These scaffolds were evaluated by cell proliferation, alkaline phosphatase activity, and real time polymerase chain reaction with immunochemistry in order to verify their osteogenic activity. Through these studies, we demonstrated that our fabricated scaffolds were well coated with DOPA as well as grafted with rhBMP2 at a quantity of 22.7±5ng when treatment with 100ng/ml rhBMP2 and 153.3±2.4ng when treated with 500ng/ml rhBMP2. This grafting enables rhBMP2 to be released in a sustained pattern. In the in vitro results, the cell proliferation and an osteoconductivity of PCLSD 500 groups was greater than any other group. All of these results suggest that our manufactured 3D printed porous scaffold would be a useful construct for application to the bone tissue engineering field. Tissue-engineered scaffolds are not only extremely complex and cumbersome, but also use organic solvents which can negatively influence cellular function. Thus, a rapid

Anti-infective efficacy, cytocompatibility and biocompatibility of a 3D-printed osteoconductive composite scaffold functionalized with quaternized chitosan.

Science.gov (United States)

Yang, Ying; Yang, Shengbing; Wang, Yugang; Yu, Zhifeng; Ao, Haiyong; Zhang, Hongbo; Qin, Ling; Guillaume, Olivier; Eglin, David; Richards, R Geoff; Tang, Tingting

2016-12-01

Contaminated or infected bone defects remain serious challenges in clinical trauma and orthopaedics, and a bone substitute with both osteoconductivity and antibacterial properties represents an improvement for treatment strategy. In this study, quaternized chitosan (hydroxypropyltrimethyl ammonium chloride chitosan, HACC) was grafted to 3D-printed scaffolds composed of polylactide-co-glycolide (PLGA) and hydroxyapatite (HA), in order to design bone engineering scaffolds endowed with antibacterial and osteoconductive properties. We found that both the PLGA/HA/HACC and PLGA/HACC composite scaffolds decreased bacterial adhesion and biofilm formation under in vitro and in vivo conditions. Additionally, ATP leakage assay indicated that immobilizing HACC on the scaffolds could effectively disrupt microbial membranes. Using human bone marrow-derived mesenchymal stem cells (hBMSCs), we demonstrated that HA incorporated scaffolds, including PLGA/HA and PLGA/HA/HACC, favoured cell attachment, proliferation, spreading and osteogenic differentiation compared to HA-free PLGA or PLGA/HACC scaffolds. Finally, an in vivo biocompatibility assay conducted on rats, showed that HA incorporated scaffolds (including PLGA/HA and PLGA/HA/HACC scaffolds) exhibited good neovascularization and tissue integration. Taken together, our findings support the approach for developing porous PLGA/HA/HACC composite scaffold with potential clinical application in the treatment of infected bone. Although plenty of conductive scaffold biomaterials have been exploited to improve bone regeneration under infection, potential tissue toxicity under high concentration and antibiotic-resistance are their main deficiencies. This study indicated that HACC-grafted PLGA/HA composite scaffold prepared using an innovative 3D-printing technique and covalent grafting strategy showed significantly enhanced antibacterial activities, especially against the antibiotic-resistant strains, together with good osteogenic

Three-dimensional electrospun polycaprolactone (PCL)/alginate hybrid composite scaffolds.

Science.gov (United States)

Kim, Min Seong; Kim, GeunHyung

2014-12-19

Micro/nanofibrous scaffolds have been used widely in biomedical applications because the micro/nano-scale fibres resemble natural extracellular matrix and the high surface-to-volume ratio encourages cellular activities (attachment and proliferation). However, poor mechanical properties, low controllability of various shapes and difficulties in obtaining controllable pore structure have been obstacles to their use in hard-tissue regeneration. To overcome these shortcomings, we suggest a new composite system, which uses a combination method of wet electrospinning, rapid prototyping and a physical punching process. Using the process, we obtained polycaprolactone (PCL)/alginate composite scaffolds, consisting of electrospun PCL/alginate fibres and micro-sized PCL struts, with mean pore sizes of 821 ± 55 μm. To show the feasibility of the scaffolds for hard-tissue regeneration, the scaffolds were assessed not only for physical properties, including hydrophilicity, water absorption, and tensile and compressive strength, but also in vitro cellular responses (cell viability and proliferation) and osteogenic differentiation (alkaline phosphatase (ALP) activity, and mineralisation) by culturing with pre-osteoblasts (MC3T3-E1 cells). With the reinforcing micro-sized PCL struts, the elastic modulus of the PCL/alginate scaffold was significantly improved versus a pure PCL scaffold. Additionally, due to the alginate component in the fibrous scaffold, they showed significantly enhanced hydrophilic behaviour, water absorption (∼8-fold) and significant biological activities (∼1.6-fold for cell viability at 7 days, ∼2.3-fold for ALP activity at 14 days and ∼6.4-fold for calcium mineralisation at 14 days) compared with those of a pure PCL fibrous scaffold. Copyright © 2014 Elsevier Ltd. All rights reserved.

Development of various composition multicomponent chitosan/fish collagen/glycerin 3D porous scaffolds: Effect on morphology, mechanical strength, biostability and cytocompatibility.

Science.gov (United States)

Ullah, Saleem; Zainol, Ismail; Chowdhury, Shiplu Roy; Fauzi, M B

2018-05-01

The various composition multicomponent chitosan/fish collagen/glycerin 3D porous scaffolds were developed and investigated the effect of various composition chitosan/fish collagen/glycerin on scaffolds morphology, mechanical strength, biostability and cytocompatibility. The scaffolds were fabricated via freeze-drying technique. The effects of various compositions consisting in 3D scaffolds were investigated via FT-IR analysis, porosity, swelling and mechanical tests, and effect on the morphology of scaffolds investigated microscopically. The biostability and cytocompatibility tests were used to explore the ability of scaffolds to use for tissue engineering application. The average pore sizes of scaffolds were in range of 100.73±27.62-116.01±52.06, porosity 71.72±3.46-91.17±2.42%, tensile modulus in dry environment 1.47±0.08-0.17±0.03MPa, tensile modulus in wet environment 0.32±0.03-0.14±0.04MPa and biodegradation rate (at day 30) 60.38±0.70-83.48±0.28%. In vitro culture of human fibroblasts and keratinocytes showed that the various composition multicomponent 3D scaffolds were good cytocompatibility however, the scaffolds contained high amount of fish collagen excellently facilitated cell proliferation and adhesion. It was found that the high amount fish collagen and glycerin scaffolds have high porosity, enough mechanical strength and biostability, and excellent cytocompatibility. Copyright © 2018 Elsevier B.V. All rights reserved.

Pore architecture and cell viability on freeze dried 3D recombinant human collagen-peptide (RHC)-chitosan scaffolds.

Science.gov (United States)

Zhang, Jing; Zhou, Aimei; Deng, Aipeng; Yang, Yang; Gao, Lihu; Zhong, Zhaocai; Yang, Shulin

2015-04-01

Pore architecture of 3D scaffolds used in tissue engineering plays a critical role in the maintenance of cell survival, proliferation and further promotion of tissue regeneration. We investigated the pore size and structure, porosity, swelling as well as cell viability of a series of recombinant human collagen-peptide-chitosan (RHCC) scaffolds fabricated by lyophilization. In this paper, freezing regime containing a final temperature of freezing (Tf) and cooling rates was applied to obtain scaffolds with pore size ranging from 100μm to 120μm. Other protocols of RHC/chitosan suspension concentration and ratio modification were studied to produce more homogenous and appropriate structural scaffolds. The mean pore size decreased along with the decline of Tf at a slow cooling rate of 0.7°C/min; a more rapid cooling rate under 5°C/min resulted to a smaller pore size and more homogenous microstructure. High concentration could reduce pore size and lead to thick well of scaffold, while improved the ratio of RHC, lamellar and fiber structure coexisted with cellular pores. Human umbilical vein endothelial cells (HUVECs) were seeded on these manufactured scaffolds, the cell viability represented a negative correlation to the pore size. This study provides an alternative method to fabricate 3D RHC-chitosan scaffolds with appropriate pores for potential tissue engineering. Copyright © 2014 Elsevier B.V. All rights reserved.

Direct write printing of three-dimensional ZrO2 biological scaffolds

International Nuclear Information System (INIS)

Li, Ya-yun; Li, Long-tu; Li, Bo

2015-01-01

Graphical abstract: Three-dimensional (3D) zirconium dioxide (ZrO 2 ) scaffolds have been fabricated for biological engineering by direct write printing method. The water-based ZrO 2 ink with a solid content fraction of 70 wt% was deposited through a fine nozzle on the substrate by a layer-by-layer sequence to produce the 3D microperiodic structures. Under a microscope, the proliferation of HCT116 cells can be observed around the 3D ZrO 2 scaffolds. 3D porous internal architecture is beneficial for cell growth by providing more locations for cell attachment and proliferation. The largest value of compressive strength reached 10 MPa, which is more than that of the hydroxyapatite (HAp) scaffold. The ability of printing 3D scaffolds with the high precise control of their internal architecture is the unique characteristics performed by the direct write technique, which will provide potential application of biomaterials and tissue engineering scaffolds. (a) Top view of the sintered 3D woodpile ZrO 2 scaffold; (b) top view of the sintered 3D cylindrical ZrO 2 scaffold. - Highlights: • 3D cylindrical and woodpile ZrO 2 scaffolds were fabricated by direct write printing method. • The compressive strength of the sample with porosity about 63% was 8 MPa. • The compressive strength of the porosity 55% sample was 10 MPa. • 3D porous ZrO 2 scaffolds with interconnected architecture are beneficial for cell attachment and proliferation. - Abstract: Three-dimensional (3D) zirconium dioxide (ZrO 2 ) scaffolds have been fabricated for biological engineering by direct write printing method. The water-based ZrO 2 ink with a solid content fraction of 70 wt% was deposited through a fine nozzle on the substrate by a layer-by-layer sequence to produce the 3D microperiodic structures. The preparation and the rheological behavior of this ink, as well as the principles of the direct write printing process were investigated systematically. Sintered at 1250 °C for 4 h was the optimal

Nanosized Mesoporous Bioactive Glass/Poly(lactic-co-glycolic Acid Composite-Coated CaSiO3 Scaffolds with Multifunctional Properties for Bone Tissue Engineering

Directory of Open Access Journals (Sweden)

Mengchao Shi

2014-01-01

Full Text Available It is of great importance to prepare multifunctional scaffolds combining good mechanical strength, bioactivity, and drug delivery ability for bone tissue engineering. In this study, nanosized mesoporous bioglass/poly(lactic-co-glycolic acid composite-coated calcium silicate scaffolds, named NMBG-PLGA/CS, were successfully prepared. The morphology and structure of the prepared scaffolds were characterized by scanning electron microscopy and X-ray diffraction. The effects of NMBG on the apatite mineralization activity and mechanical strength of the scaffolds and the attachment, proliferation, and alkaline phosphatase activity of MC3T3 cells as well as drug ibuprofen delivery properties were systematically studied. Compared to pure CS scaffolds and PLGA/CS scaffolds, the prepared NMBG-PLGA/CS scaffolds had greatly improved apatite mineralization activity in simulated body fluids, much higher mechanical property, and supported the attachment of MC3T3 cells and enhanced the cell proliferation and ALP activity. Furthermore, the prepared NMBG-PLGA/CS scaffolds could be used for delivering ibuprofen with a sustained release profile. Our study suggests that the prepared NMBG-PLGA/CS scaffolds have improved physicochemical, biological, and drug-delivery property as compared to conventional CS scaffolds, indicating that the multifunctional property of the prepared scaffolds for the potential application of bone tissue engineering.

Neural Stem Cells (NSCs in 3D Collagen Scaffolds: developing pharmacologically monitored neuroimplants for Spinal Cord Injury (SCI

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Alexandra Kourgiantaki

2014-06-01

Full Text Available Spinal cord injury, a traumatic disease characterised by a massive degeneration of neural tissue, was recently targeted for neuroregenerative interventions. Our approach is the development of pharmacologically pulsed neuroimplants using 3D collagen scaffolds hosting NSCs. We aim to monitor the properties of NSCs ex vivo and in vivo, using synthetic small molecules with neuroprotective and neurogenic properties. Synthetic, highly lipophilic CNS bioavailable small molecules, synthesized by our group (microneurotrophins, bind to neurotrophins receptors (Gravanis et al, Science Signaling, 2012, Calogeropoulou et al., J Med Chem., 2009. BNN27 can specifically interact with TrkA and p75NTR receptors activating specific signalling pathways controlling neuronal cell survival and neurogenesis (Charalampopoulos et al, PNAS, 2004, Lazaridis et al., PLoS Biol., 2011. We are seeding embryonic and adult mouse NSC on collagen 3D scaffolds of different composition (collagen, chondroitin-6-sulphate and gelatin and construction (size of pores and stiffness, testing cell behaviour (survival, proliferation or differentiation in basal conditions or pulsed with neurotrophins and/or microneurotrophins. Using the knock in sox2-egfp mice strain and fluorescence activated cell sorting (FACS analysis, we obtain NSCs cultures with a sox2-positive population more than 90% pure. We evaluate specific markers of proliferation (ki67 and/or differentiation (GFAP for glial cells, Tuj1 for mature neurons and O4 for oligodendrocytes: we are currently testing the possible effect of BNN27 on proliferation of cortical NSCs in 2D cultures (increased numbers of ki67 positive cells up to 12%. The composition and the structure of 3D scaffolds seem to play a significant functional role: scaffolds with a combined composition such as 50% collagen/50% gelatin and 92% collagen/8% chondroitin-6-sulphate support NSC survival since they sustain sox2 expression and propagate neurosphere formation

Pore architecture and cell viability on freeze dried 3D recombinant human collagen-peptide (RHC)–chitosan scaffolds

Energy Technology Data Exchange (ETDEWEB)

Zhang, Jing; Zhou, Aimei; Deng, Aipeng [School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094 (China); Yang, Yang [Faculty of Engineering, University of Nottingham, Nottingham NG7 2RD (United Kingdom); Gao, Lihu; Zhong, Zhaocai [School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094 (China); Yang, Shulin, E-mail: yshulin@njust.edu.cn [School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094 (China)

2015-04-01

Pore architecture of 3D scaffolds used in tissue engineering plays a critical role in the maintenance of cell survival, proliferation and further promotion of tissue regeneration. We investigated the pore size and structure, porosity, swelling as well as cell viability of a series of recombinant human collagen-peptide–chitosan (RHCC) scaffolds fabricated by lyophilization. In this paper, freezing regime containing a final temperature of freezing (T{sub f}) and cooling rates was applied to obtain scaffolds with pore size ranging from 100 μm to 120 μm. Other protocols of RHC/chitosan suspension concentration and ratio modification were studied to produce more homogenous and appropriate structural scaffolds. The mean pore size decreased along with the decline of T{sub f} at a slow cooling rate of 0.7 °C/min; a more rapid cooling rate under 5 °C/min resulted to a smaller pore size and more homogenous microstructure. High concentration could reduce pore size and lead to thick well of scaffold, while improved the ratio of RHC, lamellar and fiber structure coexisted with cellular pores. Human umbilical vein endothelial cells (HUVECs) were seeded on these manufactured scaffolds, the cell viability represented a negative correlation to the pore size. This study provides an alternative method to fabricate 3D RHC–chitosan scaffolds with appropriate pores for potential tissue engineering. - Highlights: • Fabrication of recombinant human collagen-chitosan scaffolds by freezing drying • Influence of freeze drying protocols on lyophilized scaffolds • Pore size, microstructure, porosity, swelling and cell viability were compared. • The optimized porous scaffold is suitable for cell (HUVEC) seeding.

Pore architecture and cell viability on freeze dried 3D recombinant human collagen-peptide (RHC)–chitosan scaffolds

International Nuclear Information System (INIS)

Zhang, Jing; Zhou, Aimei; Deng, Aipeng; Yang, Yang; Gao, Lihu; Zhong, Zhaocai; Yang, Shulin

2015-01-01

Pore architecture of 3D scaffolds used in tissue engineering plays a critical role in the maintenance of cell survival, proliferation and further promotion of tissue regeneration. We investigated the pore size and structure, porosity, swelling as well as cell viability of a series of recombinant human collagen-peptide–chitosan (RHCC) scaffolds fabricated by lyophilization. In this paper, freezing regime containing a final temperature of freezing (T f ) and cooling rates was applied to obtain scaffolds with pore size ranging from 100 μm to 120 μm. Other protocols of RHC/chitosan suspension concentration and ratio modification were studied to produce more homogenous and appropriate structural scaffolds. The mean pore size decreased along with the decline of T f at a slow cooling rate of 0.7 °C/min; a more rapid cooling rate under 5 °C/min resulted to a smaller pore size and more homogenous microstructure. High concentration could reduce pore size and lead to thick well of scaffold, while improved the ratio of RHC, lamellar and fiber structure coexisted with cellular pores. Human umbilical vein endothelial cells (HUVECs) were seeded on these manufactured scaffolds, the cell viability represented a negative correlation to the pore size. This study provides an alternative method to fabricate 3D RHC–chitosan scaffolds with appropriate pores for potential tissue engineering. - Highlights: • Fabrication of recombinant human collagen-chitosan scaffolds by freezing drying • Influence of freeze drying protocols on lyophilized scaffolds • Pore size, microstructure, porosity, swelling and cell viability were compared. • The optimized porous scaffold is suitable for cell (HUVEC) seeding

Chitosan-g-lactide copolymers for fabrication of 3D scaffolds for tissue engineering

Science.gov (United States)

Demina, T. S.; Zaytseva-Zotova, D. S.; Timashev, P. S.; Bagratashvili, V. N.; Bardakova, K. N.; Sevrin, Ch; Svidchenko, E. A.; Surin, N. M.; Markvicheva, E. A.; Grandfils, Ch; Akopova, T. A.

2015-07-01

Chitosan-g-oligo (L, D-lactide) copolymers were synthesized and assessed to fabricate a number of 3D scaffolds using a variety of technologies such as oil/water emulsion evaporation technique, freeze-drying and two-photon photopolymerization. Solid-state copolymerization method allowed us to graft up to 160 wt-% of oligolactide onto chitosan backbone via chitosan amino group acetylation with substitution degree reaching up to 0.41. Grafting of hydrophobic oligolactide side chains with polymerization degree up to 10 results in chitosan amphiphilic properties. The synthesized chitosan-g-lactide copolymers were used to design 3D scaffolds for tissue engineering such as spherical microparticles and macroporous hydrogels.

3D- Printed Poly(ε-caprolactone) Scaffold Integrated with Cell-laden Chitosan Hydrogels for Bone Tissue Engineering

OpenAIRE

Dong, Liang; Wang, Shao-Jie; Zhao, Xin-Rong; Zhu, Yu-Fang; Yu, Jia-Kuo

2017-01-01

Synthetic polymeric scaffolds are commonly used in bone tissue engineering (BTE) due to their biocompatibility and adequate mechanical properties. However, their hydrophobicity and the lack of specific cell recognition sites confined their practical application. In this study, to improve the cell seeding efficiency and osteoinductivity, an injectable thermo-sensitive chitosan hydrogel (CSG) was incorporated into a 3D-printed poly(ε-caprolactone) (PCL) scaffold to form a hybrid scaffold. To de...

Enhanced osteogenic activity of poly(ester urea) scaffolds using facile post-3D printing peptide functionalization strategies.

Science.gov (United States)

Li, Shan; Xu, Yanyi; Yu, Jiayi; Becker, Matthew L

2017-10-01

Additive manufacturing has the potential to revolutionize regenerative medicine, but the harsh thermal or photochemical conditions during the 3D printing process limit the inclusion of drugs, growth factors and other biologics within the resulting scaffolds. Functionalization strategies that enable specific placement of bioactive species on the surface of 3D printed structures following the printing process afford a promising approach to sidestep the harsh conditions and incorporate these valuable bioactive molecules with precise control over concentration. Herein, resorbable polymer scaffolds were prepared from propargyl functionalized L-phenylalanine-based poly(ester urea)s (PEUs). Osteogenic growth peptide (OGP) or bone morphogenic protein-2 (BMP-2) peptides were immobilized on PEU scaffolds through surface available propargyl groups via copper-catalyzed azide alkyne cycloaddition (CuAAC) post 3D printing. The presence of either OGP or BMP-2 significantly enhanced hMSCs osteogenic differentiation compared to unfunctionalized scaffolds. Copyright © 2017 Elsevier Ltd. All rights reserved.

Bone tissue engineering scaffolding: computer-aided scaffolding techniques.

Science.gov (United States)

Thavornyutikarn, Boonlom; Chantarapanich, Nattapon; Sitthiseripratip, Kriskrai; Thouas, George A; Chen, Qizhi

Tissue engineering is essentially a technique for imitating nature. Natural tissues consist of three components: cells, signalling systems (e.g. growth factors) and extracellular matrix (ECM). The ECM forms a scaffold for its cells. Hence, the engineered tissue construct is an artificial scaffold populated with living cells and signalling molecules. A huge effort has been invested in bone tissue engineering, in which a highly porous scaffold plays a critical role in guiding bone and vascular tissue growth and regeneration in three dimensions. In the last two decades, numerous scaffolding techniques have been developed to fabricate highly interconnective, porous scaffolds for bone tissue engineering applications. This review provides an update on the progress of foaming technology of biomaterials, with a special attention being focused on computer-aided manufacturing (Andrade et al. 2002) techniques. This article starts with a brief introduction of tissue engineering (Bone tissue engineering and scaffolds) and scaffolding materials (Biomaterials used in bone tissue engineering). After a brief reviews on conventional scaffolding techniques (Conventional scaffolding techniques), a number of CAM techniques are reviewed in great detail. For each technique, the structure and mechanical integrity of fabricated scaffolds are discussed in detail. Finally, the advantaged and disadvantage of these techniques are compared (Comparison of scaffolding techniques) and summarised (Summary).

3D printing of porous hydroxyapatite scaffolds intended for use in bone tissue engineering applications.

Science.gov (United States)

Cox, Sophie C; Thornby, John A; Gibbons, Gregory J; Williams, Mark A; Mallick, Kajal K

2015-02-01

A systematic characterisation of bone tissue scaffolds fabricated via 3D printing from hydroxyapatite (HA) and poly(vinyl)alcohol (PVOH) composite powders is presented. Flowability of HA:PVOH precursor materials was observed to affect mechanical stability, microstructure and porosity of 3D printed scaffolds. Anisotropic behaviour of constructs and part failure at the boundaries of interlayer bonds was highlighted by compressive strength testing. A trade-off between the ability to facilitate removal of PVOH thermal degradation products during sintering and the compressive strength of green parts was revealed. The ultimate compressive strength of 55% porous green scaffolds printed along the Y-axis and dried in a vacuum oven for 6h was 0.88 ± 0.02 MPa. Critically, the pores of 3D printed constructs could be user designed, ensuring bulk interconnectivity, and the imperfect packing of powder particles created an inherent surface roughness and non-designed porosity within the scaffold. These features are considered promising since they are known to facilitate osteoconduction and osteointegration in-vivo. Characterisation techniques utilised in this study include two funnel flow tests, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), compressive strength testing and computed tomography (CT). Copyright © 2014 Elsevier B.V. All rights reserved.

HIV p24 as scaffold for presenting conformational HIV Env antigens.

Directory of Open Access Journals (Sweden)

Maria Tagliamonte

Full Text Available Heterologous protein scaffolds engrafted with structurally defined HIV Env epitopes recognized by broadly neutralizing monoclonal antibodies (MAbs represent a promising strategy to elicit broad neutralizing antibodies. In such regards, a protein scaffold based on the HIV p24 CA protein is a highly attractive approach, providing also Gag epitopes for eliciting HIV non-neutralizing protective antibodies and specific CD4(+ and CD8(+ T cell responses. In the present study, computational techniques were employed to verify the presence of acceptor sites for conformational HIV Env epitopes and, as proof of concept, the analysis of HIV p24 CA-based scaffolds using a complete V3 loop in a MAb-bound conformation is presented. The V3-p24 epitope-scaffold proteins show the formation of capsomers made of hexamers similarly to the p24 wild type protein. Moreover, the conformational V3 loop presented on p24 scaffold is recognized by a panel of anti-V3 MAbs. The results suggest that HIV p24 CA protein has suitable acceptor sites for engrafting foreign epitopes, without disrupting the formation of capsomer hexamer structures, and that the V3 epitope does retain its antibody-bound conformation. This strongly support the feasibility of developing a scaffolding strategy based on p24 CA proteins displaying conformational minimal structural, antigenic HIV Env epitopes.

[Gelatin/alginate hydrogel scaffolds prepared by 3D bioprinting promotes cell adhesion and proliferation of human dental pulp cells in vitro].

Science.gov (United States)

Yu, Hai-Yue; Ma, Dan-Dan; Wu, Bu-Ling

2017-05-20

To evaluate the cytotoxicity of gelatin/alginate hydrogel scaffolds prepared by 3D bioprinting in human dental pulp cells (HDPCs) and compare the cell adhesion and proliferation of the cells seeded in the biomaterial using two different methods. HDPCs isolated by tissue block culture and enzyme digestion were cultured and passaged. Gelatin/alginate hydrogel scaffolds were printed using a bioplotter, and the cytotoxicity of the aqueous extracts of the scaffold material was tested in the third passage of HDPCs using cell counting kit-8. Scanning electron microscopy and trypan blue were used to assess the adhesion and proliferation of the cells seeded in the scaffold material at a low or high concentration. The aqueous extract of the scaffolds at different concentrations showed no obvious cytotoxicity and promoted the proliferation of HDPCs. The scaffolds had a good biocompatibility and HDPCs seeded in the scaffold showed good cell growth. Cell seeding at a high concentration in the scaffold better promoted the adhesion of HDPCs and resulted in a greater cell number on the scaffold surface compared with low-concentration cell seeding after a 5-day culture (Palginate hydrogel scaffolds prepared by 3D bioprinting has a good biocompatibility and promotes the proliferation of HDPCs, and can be used as a scaffold material for tooth regeneration. Cell seeding at a high concentration can better promote cell adhesion to the scaffold material.

Fabrication and in vitro biocompatibility of biomorphic PLGA/nHA composite scaffolds for bone tissue engineering

International Nuclear Information System (INIS)

Qian, Junmin; Xu, Weijun; Yong, Xueqing; Jin, Xinxia; Zhang, Wei

2014-01-01

In this study, biomorphic poly(DL-lactic-co-glycolic acid)/nano-hydroxyapatite (PLGA/nHA) composite scaffolds were successfully prepared using cane as a template. The porous morphology, phase, compression characteristics and in vitro biocompatibility of the PLGA/nHA composite scaffolds and biomorphic PLGA scaffolds as control were investigated. The results showed that the biomorphic scaffolds preserved the original honeycomb-like architecture of cane and exhibited a bimodal porous structure. The average channel diameter and micropore size of the PLGA/nHA composite scaffolds were 164 ± 52 μm and 13 ± 8 μm, respectively, with a porosity of 89.3 ± 1.4%. The incorporation of nHA into PLGA decreased the degree of crystallinity of PLGA, and significantly improved the compressive modulus of biomorphic scaffolds. The in vitro biocompatibility evaluation with MC3T3-E1 cells demonstrated that the biomorphic PLGA/nHA composite scaffolds could better support cell attachment, proliferation and differentiation than the biomorphic PLGA scaffolds. The localization depth of MC3T3-E1 cells within the channels of the biomorphic PLGA/nHA composite scaffolds could reach approximately 400 μm. The results suggested that the biomorphic PLGA/nHA composite scaffolds were promising candidates for bone tissue engineering. - Highlights: • Novel biomimetic PLGA/nHA composite scaffolds were successfully prepared. • nHA addition improved elastic modulus of PLGA scaffold and decreased its crystallinity. • PLGA/nHA composite scaffolds had better biocompatibility than PLGA scaffolds. • Biomorphic PLGA/nHA composite scaffold had great potential in bone tissue engineering

Fabrication and in vitro biocompatibility of biomorphic PLGA/nHA composite scaffolds for bone tissue engineering

Energy Technology Data Exchange (ETDEWEB)

Qian, Junmin, E-mail: jmqian@mail.xjtu.edu.cn; Xu, Weijun; Yong, Xueqing; Jin, Xinxia; Zhang, Wei

2014-03-01

In this study, biomorphic poly(DL-lactic-co-glycolic acid)/nano-hydroxyapatite (PLGA/nHA) composite scaffolds were successfully prepared using cane as a template. The porous morphology, phase, compression characteristics and in vitro biocompatibility of the PLGA/nHA composite scaffolds and biomorphic PLGA scaffolds as control were investigated. The results showed that the biomorphic scaffolds preserved the original honeycomb-like architecture of cane and exhibited a bimodal porous structure. The average channel diameter and micropore size of the PLGA/nHA composite scaffolds were 164 ± 52 μm and 13 ± 8 μm, respectively, with a porosity of 89.3 ± 1.4%. The incorporation of nHA into PLGA decreased the degree of crystallinity of PLGA, and significantly improved the compressive modulus of biomorphic scaffolds. The in vitro biocompatibility evaluation with MC3T3-E1 cells demonstrated that the biomorphic PLGA/nHA composite scaffolds could better support cell attachment, proliferation and differentiation than the biomorphic PLGA scaffolds. The localization depth of MC3T3-E1 cells within the channels of the biomorphic PLGA/nHA composite scaffolds could reach approximately 400 μm. The results suggested that the biomorphic PLGA/nHA composite scaffolds were promising candidates for bone tissue engineering. - Highlights: • Novel biomimetic PLGA/nHA composite scaffolds were successfully prepared. • nHA addition improved elastic modulus of PLGA scaffold and decreased its crystallinity. • PLGA/nHA composite scaffolds had better biocompatibility than PLGA scaffolds. • Biomorphic PLGA/nHA composite scaffold had great potential in bone tissue engineering.

Scaffolding Proteins: Not Such Innocent Bystanders

OpenAIRE

Smith, F. Donelson; Scott, John D.

2013-01-01

Sequential transfer of information from one enzyme to the next within the confines of a protein kinase scaffold enhances signal transduction. Though frequently considered to be inert organizational elements, two recent reports implicate kinase-scaffolding proteins as active participants in signal relay.

Decellularized Human Dental Pulp as a Scaffold for Regenerative Endodontics.

Science.gov (United States)

Song, J S; Takimoto, K; Jeon, M; Vadakekalam, J; Ruparel, N B; Diogenes, A

2017-06-01

Teeth undergo postnatal organogenesis relatively late in life and only complete full maturation a few years after the crown first erupts in the oral cavity. At this stage, development can be arrested if the tooth organ is damaged by either trauma or caries. Regenerative endodontic procedures (REPs) are a treatment alternative to conventional root canal treatment for immature teeth. These procedures rely on the transfer of apically positioned stem cells, including stem cells of the apical papilla (SCAP), into the root canal system. Although clinical success has been reported for these procedures, the predictability of expected outcomes and the organization of the newly formed tissues are affected by the lack of an available suitable scaffold that mimics the complexity of the dental pulp extracellular matrix (ECM). In this study, we evaluated 3 methods of decellularization of human dental pulp to be used as a potential autograft scaffold. Tooth slices of human healthy extracted third molars were decellularized by 3 different methods. One of the methods generated the maximum observed decellularization with minimal impact on the ECM composition and organization. Furthermore, recellularization of the scaffold supported the proliferation of SCAP throughout the scaffold with differentiation into odontoblast-like cells near the dentinal walls. Thus, this study reports that human dental pulp from healthy extracted teeth can be successfully decellularized, and the resulting scaffold supports the proliferation and differentiation of SCAP. The future application of this form of an autograft in REPs can fulfill a yet unmet need for a suitable scaffold, potentially improving clinical outcomes and ultimately promoting the survival and function of teeth with otherwise poor prognosis.

Effect of biomimetic 3D environment of an injectable polymeric scaffold on MG-63 osteoblastic-cell response

International Nuclear Information System (INIS)

Verma, Shalini; Kumar, Neeraj

2010-01-01

Solid PLGA microspheres were fabricated and characterized in terms of their in vitro degradation behaviour. Microsphere scaffolds were then modified covalently by P-15 (GTPGPQGIAGQRGVV) to obtain a 3D bioactive collagen surrogate matrix for bone filling applications. These scaffolds were characterized for surface topography, hydrophilicity and evaluated for their effect on osteoblastic activity of MG-63 cell line vis-a-vis 2D monolayer culture. AFM and contact angle experiments indicated enhanced nano-level roughness and hydrophilicity on P-15 modification. Modified scaffolds showed enhanced cell attachment, proliferation, extracellular matrix formation, mineralization and collagen type-I expression when compared to unmodified microspheres, prerequisite for bone filling applications. On long term in vitro cell culture, however, decreased cell viability was observed which may be attributed to the acidic microenvironment generated due to polymer degradation and reduction in nutrient diffusion through the copious ECM formed in 3D scaffolds. Though a higher cell count could be obtained in 2D monolayer cell culture, it was overshadowed by weak cell attachment, poor phenotypic characteristics, decreased cell viability and low mineralization levels, over 28 day cell culture studies. Results indicate that P-15 modified microsphere scaffolds may provide a natural, biomimetic 3D environment and may be successfully exploited for non-invasive bone filling applications.

Preparation, characterization and biological test of 3D-scaffolds based on chitosan, fibroin and hydroxyapatite for bone tissue engineering

International Nuclear Information System (INIS)

Lima, Paulo Autran Leite; Resende, Cristiane Xavier; Dulce de Almeida Soares, Glória; Anselme, Karine; Almeida, Luís Eduardo

2013-01-01

This work describes the preparation and characterization of porous 3D-scaffolds based on chitosan (CHI), chitosan/silk fibroin (CHI/SF) and chitosan/silk fibroin/hydroxyapatite (CHI/SF/HA) by freeze drying. The biomaterials were characterized by X-ray diffraction, attenuated total reflection Fourier transform infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry, scanning electron microscopy and energy dispersive spectroscopy. In addition, studies of porosity, pore size, contact angle and biological response of SaOs-2osteoblastic cells were performed. The CHI scaffolds have a porosity of 94.2 ± 0.9%, which is statistically higher than the one presented by CHI/SF/HA scaffolds, 89.7 ± 2.6%. Although all scaffolds were able to promote adhesion, growth and maintenance of osteogenic differentiation of SaOs-2 cells, the new 3D-scaffold based on CHI/SF/HA showed a significantly higher cell growth at 7 days and 21 days and the level of alkaline phosphatase at 14 and 21 days was statistically superior compared to other tested materials. - Highlights: • Preparation of 3D-scaffolds based on CHI, with or without addition of SF and HA. • Scaffolds exhibited interconnected porous structure (pore size superior to 50 μm). • The tripolyphosphate did not induce any significant cytotoxic response. • The CHI/SF/HA composite showed a higher cell growth and ALP activity

Functional 3-D cardiac co-culture model using bioactive chitosan nanofiber scaffolds.

Science.gov (United States)

Hussain, Ali; Collins, George; Yip, Derek; Cho, Cheul H

2013-02-01

The in vitro generation of a three-dimensional (3-D) myocardial tissue-like construct employing cells, biomaterials, and biomolecules is a promising strategy in cardiac tissue regeneration, drug testing, and tissue engineering applications. Despite significant progress in this field, current cardiac tissue models are not yet able to stably maintain functional characteristics of cardiomyocytes for long-term culture and therapeutic purposes. The objective of this study was to fabricate bioactive 3-D chitosan nanofiber scaffolds using an electrospinning technique and exploring its potential for long-term cardiac function in the 3-D co-culture model. Chitosan is a natural polysaccharide biomaterial that is biocompatible, biodegradable, non-toxic, and cost effective. Electrospun chitosan was utilized to provide structural scaffolding characterized by scale and architectural resemblance to the extracellular matrix (ECM) in vivo. The chitosan fibers were coated with fibronectin via adsorption in order to enhance cellular adhesion to the fibers and migration into the interfibrous milieu. Ventricular cardiomyocytes were harvested from neonatal rats and studied in various culture conditions (i.e., mono- and co-cultures) for their viability and function. Cellular morphology and functionality were examined using immunofluorescent staining for alpha-sarcomeric actin (SM-actin) and gap junction protein, Connexin-43 (Cx43). Scanning electron microscopy (SEM) and light microscopy were used to investigate cellular morphology, spatial organization, and contractions. Calcium indicator was used to monitor calcium ion flux of beating cardiomyocytes. The results demonstrate that the chitosan nanofibers retained their cylindrical morphology in long-term cell cultures and exhibited good cellular attachment and spreading in the presence of adhesion molecule, fibronectin. Cardiomyocyte mono-cultures resulted in loss of cardiomyocyte polarity and islands of non-coherent contractions. However

Structural diversification of the aminobicyclo[4.3.0]nonane skeleton using alkynylsilyl-derived allylic trichloroacetimidates.

Science.gov (United States)

Mostafa, Mohamed A B; McMillan, Angus E; Sutherland, Andrew

2017-04-05

The amino substituted bicyclo[4.3.0]nonane is a molecular scaffold found in a wide range of natural products and medicinal agents. Despite this, synthetic methods for the general preparation of this structural motif are sparse. Here we evaluate a diastereoselective approach for the preparation of vinylsilyl derived aminobicyclo[4.3.0]nonanes using a one-pot multi-bond forming process involving a Pd(ii)-catalysed Overman rearrangement, a Ru(ii)-catalysed ring closing enyne metathesis reaction, followed by a hydrogen bonding directed Diels-Alder reaction. We show that a benzyldimethylsilyl-substituted alkene analogue is amenable to further functionalisation and the late stage generation of diverse sp 3 -rich, drug-like aminobicyclo[4.3.0]nonane scaffolds with up to six stereogenic centres.

Tailorable Surface Morphology of 3D Scaffolds by Combining Additive Manufacturing with Thermally Induced Phase Separation.

Science.gov (United States)

Di Luca, Andrea; de Wijn, Joost R; van Blitterswijk, Clemens A; Camarero-Espinosa, Sandra; Moroni, Lorenzo

2017-08-01

The functionalization of biomaterials substrates used for cell culture is gearing towards an increasing control over cell activity. Although a number of biomaterials have been successfully modified by different strategies to display tailored physical and chemical surface properties, it is still challenging to step from 2D substrates to 3D scaffolds with instructive surface properties for cell culture and tissue regeneration. In this study, additive manufacturing and thermally induced phase separation are combined to create 3D scaffolds with tunable surface morphology from polymer gels. Surface features vary depending on the gel concentration, the exchanging temperature, and the nonsolvent used. When preosteoblasts (MC-3T3 cells) are cultured on these scaffolds, a significant increase in alkaline phosphatase activity is measured for submicron surface topography, suggesting a potential role on early cell differentiation. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Effects of Neutralization and Crosslinking Agents on the Morphology of Chitosan Electrospun Scaffolds

Directory of Open Access Journals (Sweden)

Maryam Mashayekhi

2017-01-01

Full Text Available Chitosan, a natural polymer derived from chitin by deacetylation process of chitin, has gained an enormous interest in tissue engineering due to its unique features such as antibacterial activity and wound healing properties. Electrospinning of acidified chitosan solution is one of the most widely-used approaches in fabrication of 3D scaffolds. Although there are some reports addressing morphology tailoring of the chitosan nanofibers through solution electrospinning, there is no comparative report concerning the neutralization and stabilization conditions of chitosan electrospun fibers. Therefore, this article compares the effects of different neutralizing agents such as aqueous solutions of sodium carbonate (Na2CO3 and potassium carbonate (K2CO3, and crosslinking reagents including glutaraldehyde (GA and genipin on morphology of electrospun chitosan fibers. After neutralization and stabilization processes, Fourier transform infrared spectroscopy (FTIR was employed to investigate the morphology of fibers. Furthermore, the influence of the aforementioned parameters on stability of fibers was probed using scanning electron microscopy. SEM images illustrated that the scaffold resulting from electrospinning of 4 wt% chitosan solution in a mixture of trifluoroacetic acid (TFA and dichloromethane (DCM possessed a well-formed nanofibrous structure. Afterwards, different methods for neutralization and stabilization of the electrospun chitosan nanofiber mats were performed. In this respect, aqueous solutions of both Na2CO3 and K2CO3 salts (1M were employed as neutralization agents and GA and genipin were used as two different crosslinking agents. Based on SEM analysis, the chitosan fibers, crosslinked with genipin, showed better morphology than a scaffold which was crosslinked with glutaraldehyde

Increasing the strength and bioactivity of collagen scaffolds using customizable arrays of 3D-printed polymer fibers.

Science.gov (United States)

Mozdzen, Laura C; Rodgers, Ryan; Banks, Jessica M; Bailey, Ryan C; Harley, Brendan A C

2016-03-01

Tendon is a highly aligned connective tissue which transmits force from muscle to bone. Each year, people in the US sustain more than 32 million tendon injuries. To mitigate poor functional outcomes due to scar formation, current surgical techniques rely heavily on autografts. Biomaterial platforms and tissue engineering methods offer an alternative approach to address these injuries. Scaffolds incorporating aligned structural features can promote expansion of adult tenocytes and mesenchymal stem cells capable of tenogenic differentiation. However, appropriate balance between scaffold bioactivity and mechanical strength of these constructs remains challenging. The high porosity required to facilitate cell infiltration, nutrient and oxygen biotransport within three-dimensional constructs typically results in insufficient biomechanical strength. Here we describe the use of three-dimensional printing techniques to create customizable arrays of acrylonitrile butadiene styrene (ABS) fibers that can be incorporated into a collagen scaffold under development for tendon repair. Notably, mechanical performance of scaffold-fiber composites (elastic modulus, peak stress, strain at peak stress, and toughness) can be selectively manipulated by varying fiber-reinforcement geometry without affecting the native bioactivity of the collagen scaffold. Further, we report an approach to functionalize ABS fibers with activity-inducing growth factors via sequential oxygen plasma and carbodiimide crosslinking treatments. Together, we report an adaptable approach to control both mechanical strength and presence of biomolecular cues in a manner orthogonal to the architecture of the collagen scaffold itself. Tendon injuries account for more than 32 million injuries each year in the US alone. Current techniques use allografts to mitigate poor functional outcomes, but are not ideal platforms to induce functional regeneration following injury. Tissue engineering approaches using biomaterial

Strontium hydroxyapatite/chitosan nanohybrid scaffolds with enhanced osteoinductivity for bone tissue engineering

Energy Technology Data Exchange (ETDEWEB)

Lei, Yong [The Education Ministry Key Lab of Resource Chemistry and Shanghai Key Laboratory of Rare Earth Functional Materials, Shanghai Normal University, Shanghai 200234 (China); Xu, Zhengliang [Department of Orthopedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People' s Hospital, 600 Yishan Road, Shanghai 200233 (China); Ke, Qinfei [The Education Ministry Key Lab of Resource Chemistry and Shanghai Key Laboratory of Rare Earth Functional Materials, Shanghai Normal University, Shanghai 200234 (China); Yin, Wenjing; Chen, Yixuan [Department of Orthopedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People' s Hospital, 600 Yishan Road, Shanghai 200233 (China); Zhang, Changqing, E-mail: zhangcq@sjtu.edu.cn [Department of Orthopedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People' s Hospital, 600 Yishan Road, Shanghai 200233 (China); Guo, Yaping, E-mail: ypguo@shnu.edu.cn [The Education Ministry Key Lab of Resource Chemistry and Shanghai Key Laboratory of Rare Earth Functional Materials, Shanghai Normal University, Shanghai 200234 (China)

2017-03-01

For the clinical application of bone tissue engineering with the combination of biomaterials and mesenchymal stem cells (MSCs), bone scaffolds should possess excellent biocompatibility and osteoinductivity to accelerate the repair of bone defects. Herein, strontium hydroxyapatite [SrHAP, Ca{sub 10−x}Sr{sub x}(PO{sub 4}){sub 6}(OH){sub 2}]/chitosan (CS) nanohybrid scaffolds were fabricated by a freeze-drying method. The SrHAP nanocrystals with the different x values of 0, 1, 5 and 10 are abbreviated to HAP, Sr1HAP, Sr5HAP and Sr10HAP, respectively. With increasing x values from 0 to 10, the crystal cell volumes and axial lengths of SrHAP become gradually large because of the greater ion radius of Sr{sup 2+} than Ca{sup 2+}, while the crystal sizes of SrHAP decrease from 70.4 nm to 46.7 nm. The SrHAP/CS nanohybrid scaffolds exhibits three-dimensional (3D) interconnected macropores with pore sizes of 100–400 μm, and the SrHAP nanocrystals are uniformly dispersed within the scaffolds. In vitro cell experiments reveal that all the HAP/CS, Sr1HAP/CS, Sr5HAP/CS and Sr10HAP/CS nanohybrid scaffolds possess excellent cytocompatibility with the favorable adhesion, spreading and proliferation of human bone marrow mesenchymal stem cells (hBMSCs). The Sr5HAP nanocrystals in the scaffolds do not affect the adhesion, spreading of hBMSCs, but they contribute remarkably to cell proliferation and osteogenic differentiation. As compared with the HAP/CS nanohybrid scaffold, the released Sr{sup 2+} ions from the SrHAP/CS nanohybrid scaffolds enhance alkaline phosphatase (ALP) activity, extracellular matrix (ECM) mineralization and osteogenic-related COL-1 and ALP expression levels. Especially, the Sr5HAP/CS nanohybrid scaffolds exhibit the best osteoinductivity among four groups because of the synergetic effect between Ca{sup 2+} and Sr{sup 2+} ions. Hence, the Sr5HAP/CS nanohybrid scaffolds with excellent cytocompatibility and osteogenic property have promising application for

Evaluation of synovium-derived mesenchymal stem cells and 3D printed nanocomposite scaffolds for tissue engineering

International Nuclear Information System (INIS)

Pan, Jian-Feng; Li, Shuo; Guo, Chang-An; Zhang, Feng; Yan, Zuo-Qin; Xu, Du-Liang; Mo, Xiu-Mei

2015-01-01

Stem cells and scaffolds play a very important role in tissue engineering. Here, we isolated synovium-derived mesenchymal stem cells (SMSCs) from synovial membrane tissue and characterized stem-cell properties. Gelatin nanoparticles (NP) were prepared using a two-step desolvation method and then pre-mixed into different host matrix (silk fibroin (SF), gelatin (Gel), or SF–Gel mixture) to generate various 3D printed nanocomposite scaffolds (NP/SF, NP/SF–Gel, NP/Gel-1, and NP/Gel-2). The microstructure was examined by scanning electron microscopy. Biocompatibility assessment was performed through CCK-8 assay by coculturing with SMSCs at 1, 3, 7 and 14 days. According to the results, SMSCs are similar to other MSCs in their surface epitope expression, which are negative for CD45 and positive for CD44, CD90, and CD105. After incubation in lineage-specific medium, SMSCs could differentiate into chondrocytes, osteocytes and adipocytes. 3D printed nanocomposite scaffolds exhibited a good biocompatibility in the process of coculturing with SMSCs and had no negative effect on cell behavior. The study provides a strategy to obtain SMSCs and fabricate 3D printed nanocomposite scaffolds, the combination of which could be used for practical applications in tissue engineering. (paper)

Digital micromirror device (DMD)-based 3D printing of poly(propylene fumarate) scaffolds.

Science.gov (United States)

Mott, Eric J; Busso, Mallory; Luo, Xinyi; Dolder, Courtney; Wang, Martha O; Fisher, John P; Dean, David

2016-04-01

Our recent investigations into the 3D printing of poly(propylene fumarate) (PPF), a linear polyester, using a DMD-based system brought us to a resin that used titanium dioxide (TiO2) as an ultraviolet (UV) filter for controlling cure depth. However, this material hindered the 3D printing process due to undesirable lateral or "dark" curing (i.e., in areas not exposed to light from the DMD chip). Well known from its use in sunscreen, another UV filter, oxybenzone, has previously been used in conjunction with TiO2. In this study we hypothesize that combining these two UV filters will result in a synergistic effect that controls cure depth and avoids dark cure. A resin mixture (i.e., polymer, initiator, UV filters) was identified that worked well. The resin was then further characterized through mechanical testing, cure testing, and cytotoxicity testing to investigate its use as a material for bone tissue engineering scaffolds. Results show that the final resin eliminated dark cure as shown through image analysis. Mechanically the new scaffolds proved to be far weaker than those printed from previous resins, with compressive strengths of 7.8 ± 0.5 MPa vs. 36.5 ± 1.6 MPa, respectively. The new scaffolds showed a 90% reduction in elastic modulus and a 74% increase in max strain. These properties may be useful in tissue engineering applications where resorption is required. Initial cytotoxicity evaluation was negative. As hypothesized, the use of TiO2 and oxybenzone showed synergistic effects in the 3D printing of PPF tissue engineering scaffolds. Copyright © 2015 Elsevier B.V. All rights reserved.

Effect of copper-doped silicate 13–93 bioactive glass scaffolds on the response of MC3T3-E1 cells in vitro and on bone regeneration and angiogenesis in rat calvarial defects in vivo

Energy Technology Data Exchange (ETDEWEB)

Lin, Yinan; Xiao, Wei [Department of Materials Science and Engineering, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Bal, B. Sonny [Department of Orthopaedic Surgery, University of Missouri, Columbia, MO 65212 (United States); Rahaman, Mohamed N., E-mail: rahaman@mst.edu [Department of Materials Science and Engineering, Missouri University of Science and Technology, Rolla, MO 65409 (United States)

2016-10-01

The release of inorganic ions from biomaterials could provide an alternative approach to the use of growth factors for improving tissue healing. In the present study, the release of copper (Cu) ions from bioactive silicate (13–93) glass scaffolds on the response of cells in vitro and on bone regeneration and angiogenesis in vivo was studied. Scaffolds doped with varying concentrations of Cu (0–2.0 wt.% CuO) were created with a grid-like microstructure by robotic deposition. When immersed in simulated body fluid in vitro, the Cu-doped scaffolds released Cu ions into the medium in a dose-dependent manner and converted partially to hydroxyapatite. The proliferation and alkaline phosphatase activity of pre-osteoblastic MC3T3-E1 cells cultured on the scaffolds were not affected by 0.4 and 0.8 wt.% CuO in the glass but they were significantly reduced by 2.0 wt.% CuO. The percent new bone that infiltrated the scaffolds implanted for 6 weeks in rat calvarial defects (46 ± 8%) was not significantly affected by 0.4 or 0.8 wt.% CuO in the glass whereas it was significantly inhibited (0.8 ± 0.7%) in the scaffolds doped with 2.0 wt.% CuO. The area of new blood vessels in the fibrous tissue that infiltrated the scaffolds increased with CuO content of the glass and was significantly higher for the scaffolds doped with 2.0 wt.% CuO. Loading the scaffolds with bone morphogenetic protein-2 (1 μg/defect) significantly enhanced bone infiltration and reduced fibrous tissue in the scaffolds. These results showed that doping the 13–93 glass scaffolds with up to 0.8 wt.% CuO did not affect their biocompatibility whereas 2.0 wt.% CuO was toxic to cells and detrimental to bone regeneration. - Highlights: • First study to evaluate Cu ion release from silicate (13-93) bioactive glass scaffolds on osteogenesis in vivo • Released Cu ions influenced bone regeneration in a dose dependent manner • Lower concentrations of Cu ions had little effect on bone regeneration • Cu ion

Effect of copper-doped silicate 13–93 bioactive glass scaffolds on the response of MC3T3-E1 cells in vitro and on bone regeneration and angiogenesis in rat calvarial defects in vivo

International Nuclear Information System (INIS)

Lin, Yinan; Xiao, Wei; Bal, B. Sonny; Rahaman, Mohamed N.

2016-01-01

The release of inorganic ions from biomaterials could provide an alternative approach to the use of growth factors for improving tissue healing. In the present study, the release of copper (Cu) ions from bioactive silicate (13–93) glass scaffolds on the response of cells in vitro and on bone regeneration and angiogenesis in vivo was studied. Scaffolds doped with varying concentrations of Cu (0–2.0 wt.% CuO) were created with a grid-like microstructure by robotic deposition. When immersed in simulated body fluid in vitro, the Cu-doped scaffolds released Cu ions into the medium in a dose-dependent manner and converted partially to hydroxyapatite. The proliferation and alkaline phosphatase activity of pre-osteoblastic MC3T3-E1 cells cultured on the scaffolds were not affected by 0.4 and 0.8 wt.% CuO in the glass but they were significantly reduced by 2.0 wt.% CuO. The percent new bone that infiltrated the scaffolds implanted for 6 weeks in rat calvarial defects (46 ± 8%) was not significantly affected by 0.4 or 0.8 wt.% CuO in the glass whereas it was significantly inhibited (0.8 ± 0.7%) in the scaffolds doped with 2.0 wt.% CuO. The area of new blood vessels in the fibrous tissue that infiltrated the scaffolds increased with CuO content of the glass and was significantly higher for the scaffolds doped with 2.0 wt.% CuO. Loading the scaffolds with bone morphogenetic protein-2 (1 μg/defect) significantly enhanced bone infiltration and reduced fibrous tissue in the scaffolds. These results showed that doping the 13–93 glass scaffolds with up to 0.8 wt.% CuO did not affect their biocompatibility whereas 2.0 wt.% CuO was toxic to cells and detrimental to bone regeneration. - Highlights: • First study to evaluate Cu ion release from silicate (13-93) bioactive glass scaffolds on osteogenesis in vivo • Released Cu ions influenced bone regeneration in a dose dependent manner • Lower concentrations of Cu ions had little effect on bone regeneration • Cu ion

Scanning electron microscopy and swelling test of shrimp shell chitosan and chitosan-RGD scaffolds

Science.gov (United States)

Mandacan, M. C.; Yuniastuti, M.; Amir, L. R.; Idrus, E.; Suniarti, D. F.

2017-08-01

Shrimp shell chitosan and chitosan-RGD scaffold membranes are produced to be biocompatible with tissue engineering. Nonetheless, their architectural properties have not yet been studied. Analyze the architectural properties of chitosan and chitosan-RGD scaffolds. Analyze pore count and size, interpore distance, and porosity (using SEM testing and ImageJ analysis) and water absorption (using a swelling test). The properties of the chitosan and chitosan-RGD scaffolds were as follows, respectively. The pore counts were 225 and 153; pore size, 171.4 μam and 180.2 μam interpore distance, 105.7 μam and 101.4 μam porosity, 22% and 10.2%; and water absorption, 9.1 mgH2O/mgScaffold and 19.3 mgH2O/mgScaffold. The shrimp shell chitosan-RGD membrane scaffold was found to have architectural properties that make it more conducive to use in tissue engineering.

Cancer cell migration within 3D layer-by-layer microfabricated photocrosslinked PEG scaffolds with tunable stiffness.

Science.gov (United States)

Soman, Pranav; Kelber, Jonathan A; Lee, Jin Woo; Wright, Tracy N; Vecchio, Kenneth S; Klemke, Richard L; Chen, Shaochen

2012-10-01

Our current understanding of 3-dimensional (3D) cell migration is primarily based on results from fibrous scaffolds with randomly organized internal architecture. Manipulations that change the stiffness of these 3D scaffolds often alter other matrix parameters that can modulate cell motility independently or synergistically, making observations less predictive of how cells behave when migrating in 3D. In order to decouple microstructural influences and stiffness effects, we have designed and fabricated 3D polyethylene glycol (PEG) scaffolds that permit orthogonal tuning of both elastic moduli and microstructure. Scaffolds with log-pile architectures were used to compare the 3D migration properties of normal breast epithelial cells (HMLE) and Twist-transformed cells (HMLET). Our results indicate that the nature of cell migration is significantly impacted by the ability of cells to migrate in the third dimension. 2D ECM-coated PEG substrates revealed no statistically significant difference in cell migration between HMLE and HMLET cells among substrates of different stiffness. However, when cells were allowed to move along the third dimension, substantial differences were observed for cell displacement, velocity and path straightness parameters. Furthermore, these differences were sensitive to both substrate stiffness and the presence of the Twist oncogene. Importantly, these 3D modes of migration provide insight into the potential for oncogene-transformed cells to migrate within and colonize tissues of varying stiffness. Copyright © 2012 Elsevier Ltd. All rights reserved.

Hybrid scaffold bearing polymer-siloxane Schiff base linkage for bone tissue engineering

Energy Technology Data Exchange (ETDEWEB)

Nair, Bindu P., E-mail: bindumelekkuttu@gmail.com; Gangadharan, Dhanya; Mohan, Neethu; Sumathi, Babitha; Nair, Prabha D., E-mail: pdnair49@gmail.com

2015-07-01

Scaffolds that can provide the requisite biological cues for the fast regeneration of bone are highly relevant to the advances in tissue engineering and regenerative medicine. In the present article, we report the fabrication of a chitosan–gelatin–siloxane scaffold bearing interpolymer-siloxane Schiff base linkage, through a single-step dialdehyde cross-linking and freeze-drying method using 3-aminopropyltriethoxysilane as the siloxane precursor. Swelling of the scaffolds in phosphate buffered saline indicates enhancement with increase in siloxane concentration, whereas compressive moduli of the wet scaffolds reveal inverse dependence, owing to the presence of siloxane, rich in silanol groups. It is suggested that through the strategy of dialdehyde cross-linking, a limiting siloxane loading of 20 wt.% into a chitosan-gelatin matrix should be considered ideal for bone tissue engineering, because the scaffold made with 30 wt.% siloxane loading degrades by 48 wt.%, in 21 days. The hybrid scaffolds bearing Schiff base linkage between the polymer and siloxane, unlike the stable linkages in earlier reports, are expected to give a faster release of siloxanes and enhancement in osteogenesis. This is verified by the in vitro evaluation of the hybrid scaffolds using rabbit adipose mesenchymal stem cells, which revealed osteogenic cell-clusters on a polymer-siloxane scaffold, enhanced alkaline phosphatase activity and the expression of bone-specific genes, whereas the control scaffold without siloxane supported more of cell-proliferation than differentiation. A siloxane concentration dependent enhancement in osteogenic differentiation is also observed. - Highlights: • A hybrid scaffold bearing interpolymer-siloxane Schiff base linkage • A limiting siloxane loading of 20 wt.% into chitosan–gelatin matrix • A siloxane concentration dependent enhancement in osteogenic differentiation.

A novel nano-structured porous polycaprolactone scaffold improves hyaline cartilage repair in a rabbit model compared to a collagen type I/III scaffold: in vitro and in vivo studies.

Science.gov (United States)

Christensen, Bjørn Borsøe; Foldager, Casper Bindzus; Hansen, Ole Møller; Kristiansen, Asger Albæk; Le, Dang Quang Svend; Nielsen, Agnete Desirée; Nygaard, Jens Vinge; Bünger, Cody Erik; Lind, Martin

2012-06-01

To develop a nano-structured porous polycaprolactone (NSP-PCL) scaffold and compare the articular cartilage repair potential with that of a commercially available collagen type I/III (Chondro-Gide) scaffold. By combining rapid prototyping and thermally induced phase separation, the NSP-PCL scaffold was produced for matrix-assisted autologous chondrocyte implantation. Lyophilizing a water-dioxane-PCL solution created micro and nano-pores. In vitro: The scaffolds were seeded with rabbit chondrocytes and cultured in hypoxia for 6 days. qRT-PCR was performed using primers for sox9, aggrecan, collagen type 1 and 2. In vivo: 15 New Zealand White Rabbits received bilateral osteochondral defects in the femoral intercondylar grooves. Autologous chondrocytes were harvested 4 weeks prior to surgery. There were 3 treatment groups: (1) NSP-PCL scaffold without cells. (2) The Chondro-Gide scaffold with autologous chondrocytes and (3) NSP-PCL scaffold with autologous chondrocytes. Observation period was 13 weeks. Histological evaluation was made using the O'Driscoll score. In vitro: The expressions of sox9 and aggrecan were higher in the NSP-PCL scaffold, while expression of collagen 1 was lower compared to the Chondro-Gide scaffold. In vivo: Both NSP-PCL scaffolds with and without cells scored significantly higher than the Chondro-Gide scaffold when looking at the structural integrity and the surface regularity of the repair tissue. No differences were found between the NSP-PCL scaffold with and without cells. The NSP-PCL scaffold demonstrated higher in vitro expression of chondrogenic markers and had higher in vivo histological scores compared to the Chondro-Gide scaffold. The improved chondrocytic differentiation can potentially produce more hyaline cartilage during clinical cartilage repair. It appears to be a suitable cell-free implant for hyaline cartilage repair and could provide a less costly and more effective treatment option than the Chondro-Gide scaffold with cells.

Setd7 and its contribution to boron-induced bone regeneration in B-MBG scaffolds.

Science.gov (United States)

Yin, Chengcheng; Jia, Xiaoshi; Miron, Richard J; Long, Qiaoyun; Xu, Hudi; Wei, Yan; Wu, Min; Zhang, Yufeng; Li, Zubing

2018-04-20

Boron (B), a trace element found in the human body, plays an important role for health of bone by promoting the proliferation and differentiation of osteoblasts. Our research group previously fabricated B-mesoporous bioactive glass (MBG) scaffolds, which successfully promoted osteogenic differentiation of osteoblasts when compared to pure MBG scaffolds without boron. However, the mechanisms of the positive effect of B-MBG scaffolds on osteogenesis remains unknown. Therefore, we performed in-vivo experiments in an OVX rat models with pure MBG scaffolds and compared them to B-MBG scaffold. As a result, we found that B-MBG scaffold induced more new bone regeneration compared to pure MBG scaffold and examined genes related to bone regeneration induced by B-MBG scaffold through RNA-seq to obtain target genes and epigenetic mechanisms. The results demonstrated an increased expression and affiliation of Setd7 in the B-MBG group when compared to the MBG group. Immunofluorescent staining from our in vivo samples further demonstrated a higher localization of Setd7 and H3K4me3 in Runx2-positive cells in defects treated with B-MBG scaffolds. KEGG results suggested that specifically Wnt/β-catenin signaling pathway was highly activated in new bone area associated with B-MBG scaffolds. Thereafter, in vitro studies with human bone marrow stem cells (hBMSCs) stimulated by extracted liquid of B-MBG was associated with significantly elevated levels of Setd7, as well as H3K4me3 when compared to MBG alone. To verify the role of Setd7 in new bone formation in the presence of Boron, Setd7 was knocked down in hBMSCs with stimulation of the extracted liquids of B-MBG or MBG scaffolds. The result showed that osteoblast differentiation of hBMSCs was inhibited when Setd7 was knocked down, which could not be rescued by the extract liquids of B-MBG scaffolds confirming its role in osteoblast differentiation and bone regeneration. As a histone methylase, Setd7 may be expected to be a potential

Neuronal Networks on Nanocellulose Scaffolds.

Science.gov (United States)

Jonsson, Malin; Brackmann, Christian; Puchades, Maja; Brattås, Karoline; Ewing, Andrew; Gatenholm, Paul; Enejder, Annika

2015-11-01

Proliferation, integration, and neurite extension of PC12 cells, a widely used culture model for cholinergic neurons, were studied in nanocellulose scaffolds biosynthesized by Gluconacetobacter xylinus to allow a three-dimensional (3D) extension of neurites better mimicking neuronal networks in tissue. The interaction with control scaffolds was compared with cationized nanocellulose (trimethyl ammonium betahydroxy propyl [TMAHP] cellulose) to investigate the impact of surface charges on the cell interaction mechanisms. Furthermore, coatings with extracellular matrix proteins (collagen, fibronectin, and laminin) were investigated to determine the importance of integrin-mediated cell attachment. Cell proliferation was evaluated by a cellular proliferation assay, while cell integration and neurite propagation were studied by simultaneous label-free Coherent anti-Stokes Raman Scattering and second harmonic generation microscopy, providing 3D images of PC12 cells and arrangement of nanocellulose fibrils, respectively. Cell attachment and proliferation were enhanced by TMAHP modification, but not by protein coating. Protein coating instead promoted active interaction between the cells and the scaffold, hence lateral cell migration and integration. Irrespective of surface modification, deepest cell integration measured was one to two cell layers, whereas neurites have a capacity to integrate deeper than the cell bodies in the scaffold due to their fine dimensions and amoeba-like migration pattern. Neurites with lengths of >50 μm were observed, successfully connecting individual cells and cell clusters. In conclusion, TMAHP-modified nanocellulose scaffolds promote initial cellular scaffold adhesion, which combined with additional cell-scaffold treatments enables further formation of 3D neuronal networks.

Fabrication of novel biodegradable porous bone scaffolds based on amphiphilic hydroxyapatite nanorods

Energy Technology Data Exchange (ETDEWEB)

Zheng, Xiaoyan; Hui, Junfeng [Shaanxi Key Laboratory of Degradable Biomedical Materials, Shaanxi R& D Center of Biomaterials and Fermentation Engineering, School of Chemical and Engineering, Northwest University, Xi' an 710069, Shaanxi, PR China2 (China); Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of the Ministry of Education, Shaanxi Key Laboratory of Physico-Inorganic Chemistry, College of Chemistry & Materials Science, Northwest University, Xi' an 710069, Shaanxi (China); Li, Hui; Zhu, Chenhui [Shaanxi Key Laboratory of Degradable Biomedical Materials, Shaanxi R& D Center of Biomaterials and Fermentation Engineering, School of Chemical and Engineering, Northwest University, Xi' an 710069, Shaanxi, PR China2 (China); Hua, Xiufu, E-mail: hua_xiufu@163.com [Department of Scientific Research and Development, Tsinghua University, Beijing 100084 (China); Ma, Haixia, E-mail: mahx@nwu.edu.cn [Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of the Ministry of Education, Shaanxi Key Laboratory of Physico-Inorganic Chemistry, College of Chemistry & Materials Science, Northwest University, Xi' an 710069, Shaanxi (China); Fan, Daidi, E-mail: fandaidi@nwu.edu.cn [Shaanxi Key Laboratory of Degradable Biomedical Materials, Shaanxi R& D Center of Biomaterials and Fermentation Engineering, School of Chemical and Engineering, Northwest University, Xi' an 710069, Shaanxi, PR China2 (China)

2017-06-01

This paper describes a new synthetic strategy and biological application for novel amphiphilic hydroxyapatite (HAp) nanorods. The prepared HAp nanorods were able to be dispersed in water, ethyl alcohol and cyclohexane. The co-anchoring of the multidentate ligands of PEG 20000 and hydrophobic oleic acid (OA) on the rods' surfaces endowed them with excellent amphibious properties. Utilizing amphiphilic HAp nanorods with excellent biocompatibility as the inorganic phase, human-like collagen (HLC) as the organic phase and natural genipin as the cross-linker, optimal HLC/HAp porous scaffolds (HLC: HAp = 1:4, w/w) were fabricated. The compression stress and three-point bending strength of the scaffolds with pore diameters of 150 to 200 μm reached approximately 3.4 MPa and 5.4 MPa, respectively, and their porosity was 77.35 ± 3.75%. Cytological tests showed that HLC/HAp scaffolds could contribute to cell proliferation and differentiation. The results indicated that these novel amphiphilic HAp nanorods can be expected to become recognized as an excellent inorganic material for the porous scaffolds used in repairing bone and related applications. - Highlights: • A simple and effective hydrothermal method was developed for preparing uniform HAp nanorods with amphiphilic surfaces. • The synthesized amphiphilic HAp nanorods could be dispersed in water, ethyl alcohol or cyclohexane. • The prepared HLC/HAp porous scaffolds had good mechanical properties, biocompatibility and osteoconductive etc.

Fabrication of novel biodegradable porous bone scaffolds based on amphiphilic hydroxyapatite nanorods

International Nuclear Information System (INIS)

Zheng, Xiaoyan; Hui, Junfeng; Li, Hui; Zhu, Chenhui; Hua, Xiufu; Ma, Haixia; Fan, Daidi

2017-01-01

This paper describes a new synthetic strategy and biological application for novel amphiphilic hydroxyapatite (HAp) nanorods. The prepared HAp nanorods were able to be dispersed in water, ethyl alcohol and cyclohexane. The co-anchoring of the multidentate ligands of PEG 20000 and hydrophobic oleic acid (OA) on the rods' surfaces endowed them with excellent amphibious properties. Utilizing amphiphilic HAp nanorods with excellent biocompatibility as the inorganic phase, human-like collagen (HLC) as the organic phase and natural genipin as the cross-linker, optimal HLC/HAp porous scaffolds (HLC: HAp = 1:4, w/w) were fabricated. The compression stress and three-point bending strength of the scaffolds with pore diameters of 150 to 200 μm reached approximately 3.4 MPa and 5.4 MPa, respectively, and their porosity was 77.35 ± 3.75%. Cytological tests showed that HLC/HAp scaffolds could contribute to cell proliferation and differentiation. The results indicated that these novel amphiphilic HAp nanorods can be expected to become recognized as an excellent inorganic material for the porous scaffolds used in repairing bone and related applications. - Highlights: • A simple and effective hydrothermal method was developed for preparing uniform HAp nanorods with amphiphilic surfaces. • The synthesized amphiphilic HAp nanorods could be dispersed in water, ethyl alcohol or cyclohexane. • The prepared HLC/HAp porous scaffolds had good mechanical properties, biocompatibility and osteoconductive etc.

Characterization and evaluation of graphene oxide scaffold for periodontal wound healing of class II furcation defects in dog.

Science.gov (United States)

Kawamoto, Kohei; Miyaji, Hirofumi; Nishida, Erika; Miyata, Saori; Kato, Akihito; Tateyama, Akito; Furihata, Tomokazu; Shitomi, Kanako; Iwanaga, Toshihiko; Sugaya, Tsutomu

2018-01-01

The 3-dimensional scaffold plays a key role in volume and quality of repair tissue in periodontal tissue engineering therapy. We fabricated a novel 3D collagen scaffold containing carbon-based 2-dimensional layered material, named graphene oxide (GO). The aim of this study was to characterize and assess GO scaffold for periodontal tissue healing of class II furcation defects in dog. GO scaffolds were prepared by coating the surface of a 3D collagen sponge scaffold with GO dispersion. Scaffolds were characterized using cytotoxicity and tissue reactivity tests. In addition, GO scaffold was implanted into dog class II furcation defects and periodontal healing was investigated at 4 weeks postsurgery. GO scaffold exhibited low cytotoxicity and enhanced cellular ingrowth behavior and rat bone forming ability. In addition, GO scaffold stimulated healing of dog class II furcation defects. Periodontal attachment formation, including alveolar bone, periodontal ligament-like tissue, and cementum-like tissue, was significantly increased by GO scaffold implantation, compared with untreated scaffold. The results suggest that GO scaffold is biocompatible and possesses excellent bone and periodontal tissue formation ability. Therefore, GO scaffold would be beneficial for periodontal tissue engineering therapy.

Sulfophenyl-Functionalized Reduced Graphene Oxide Networks on Electrospun 3D Scaffold for Ultrasensitive NO₂ Gas Sensor.

Science.gov (United States)

Zou, Bin; Guo, Yunlong; Shen, Nannan; Xiao, Anshan; Li, Mingjun; Zhu, Liang; Wan, Pengbo; Sun, Xiaoming

2017-12-19

Ultrasensitive room temperature real-time NO₂ sensors are highly desirable due to potential threats on environmental security and personal respiratory. Traditional NO₂ gas sensors with highly operated temperatures (200-600 °C) and limited reversibility are mainly constructed from semiconducting oxide-deposited ceramic tubes or inter-finger probes. Herein, we report the functionalized graphene network film sensors assembled on an electrospun three-dimensional (3D) nanonetwork skeleton for ultrasensitive NO₂ sensing. The functional 3D scaffold was prepared by electrospinning interconnected polyacrylonitrile (PAN) nanofibers onto a nylon window screen to provide a 3D nanonetwork skeleton. Then, the sulfophenyl-functionalized reduced graphene oxide (SFRGO) was assembled on the electrospun 3D nanonetwork skeleton to form SFRGO network films. The assembled functionalized graphene network film sensors exhibit excellent NO₂ sensing performance (10 ppb to 20 ppm) at room temperature, reliable reversibility, good selectivity, and better sensing cycle stability. These improvements can be ascribed to the functionalization of graphene with electron-withdrawing sulfophenyl groups, the high surface-to-volume ratio, and the effective sensing channels from SFRGO wrapping onto the interconnected 3D scaffold. The SFRGO network-sensing film has the advantages of simple preparation, low cost, good processability, and ultrasensitive NO₂ sensing, all advantages that can be utilized for potential integration into smart windows and wearable electronic devices for real-time household gas sensors.

Design control for clinical translation of 3D printed modular scaffolds.

Science.gov (United States)

Hollister, Scott J; Flanagan, Colleen L; Zopf, David A; Morrison, Robert J; Nasser, Hassan; Patel, Janki J; Ebramzadeh, Edward; Sangiorgio, Sophia N; Wheeler, Matthew B; Green, Glenn E

2015-03-01

The primary thrust of tissue engineering is the clinical translation of scaffolds and/or biologics to reconstruct tissue defects. Despite this thrust, clinical translation of tissue engineering therapies from academic research has been minimal in the 27 year history of tissue engineering. Academic research by its nature focuses on, and rewards, initial discovery of new phenomena and technologies in the basic research model, with a view towards generality. Translation, however, by its nature must be directed at specific clinical targets, also denoted as indications, with associated regulatory requirements. These regulatory requirements, especially design control, require that the clinical indication be precisely defined a priori, unlike most academic basic tissue engineering research where the research target is typically open-ended, and furthermore requires that the tissue engineering therapy be constructed according to design inputs that ensure it treats or mitigates the clinical indication. Finally, regulatory approval dictates that the constructed system be verified, i.e., proven that it meets the design inputs, and validated, i.e., that by meeting the design inputs the therapy will address the clinical indication. Satisfying design control requires (1) a system of integrated technologies (scaffolds, materials, biologics), ideally based on a fundamental platform, as compared to focus on a single technology, (2) testing of design hypotheses to validate system performance as opposed to mechanistic hypotheses of natural phenomena, and (3) sequential testing using in vitro, in vivo, large preclinical and eventually clinical tests against competing therapies, as compared to single experiments to test new technologies or test mechanistic hypotheses. Our goal in this paper is to illustrate how design control may be implemented in academic translation of scaffold based tissue engineering therapies. Specifically, we propose to (1) demonstrate a modular platform approach

Effect of in vitro enzymatic degradation on 3D printed poly(ε-caprolactone) scaffolds: morphological, chemical and mechanical properties.

Science.gov (United States)

Ferreira, Joana; Gloria, Antonio; Cometa, Stefania; Coelho, Jorge F J; Domingos, Marco

2017-07-27

In recent years, the tissue engineering (TE) field has significantly benefited from advanced techniques such as additive manufacturing (AM), for the design of customized 3D scaffolds with the aim of guided tissue repair. Among the wide range of materials available to biomanufacture 3D scaffolds, poly(ε-caprolactone) (PCL) clearly arises as the synthetic polymer with the greatest potential, due to its unique properties - namely, biocompatibility, biodegradability, thermal and chemical stability and processability. This study aimed for the first time to investigate the effect of pore geometry on the in vitro enzymatic chain cleavage mechanism of PCL scaffolds manufactured by the AM extrusion process. Methods: Morphological properties of 3D printed PCL scaffolds before and after degradation were evaluated using Scanning Electron Microscopy (SEM) and micro-computed tomography (μ-CT). Differential Scanning Calorimetry (DSC) was employed to determine possible variations in the crystallinity of the scaffolds during the degradation period. The molecular weight was assessed using Size Exclusion Chromatography (SEC) while the mechanical properties were investigated under static compression conditions. Morphological results suggested a uniform reduction of filament diameter, while increasing the scaffolds' porosity. DSC analysis revealed and increment in the crystallinity degree while the molecular weight, evaluated through SEC, remained almost constant during the incubation period (25 days). Mechanical analysis highlighted a decrease in the compressive modulus and maximum stress over time, probably related to the significant weight loss of the scaffolds. All of these results suggest that PCL scaffolds undergo enzymatic degradation through a surface erosion mechanism, which leads to significant variations in mechanical, physical and chemical properties, but which has little influence on pore geometry.

Antimicrobial Effects of Novel Triple Antibiotic Paste-Mimic Scaffolds on Actinomyces naeslundii Biofilm.

Science.gov (United States)

Albuquerque, Maria T P; Ryan, Stuart J; Münchow, Eliseu A; Kamocka, Maria M; Gregory, Richard L; Valera, Marcia C; Bottino, Marco C

2015-08-01

Actinomyces naeslundii has been recovered from traumatized permanent teeth diagnosed with necrotic pulps. In this work, a triple antibiotic paste (TAP)-mimic scaffold is proposed as a drug-delivery strategy to eliminate A. naeslundii dentin biofilm. Metronidazole, ciprofloxacin, and minocycline were added to a polydioxanone (PDS) polymer solution and spun into fibrous scaffolds. Fiber morphology, mechanical properties, and drug release were investigated by using scanning electron microscopy, microtensile testing, and high-performance liquid chromatography, respectively. Human dentin specimens (4 × 4 × 1 mm(3), n = 4/group) were inoculated with A. naeslundii (ATCC 43146) for 7 days for biofilm formation. The infected dentin specimens were exposed to TAP-mimic scaffolds, TAP solution (positive control), and pure PDS (drug-free scaffold). Dentin infected (7-day biofilm) specimens were used for comparison (negative control). Confocal laser scanning microscopy was done to determine bacterial viability. Scaffolds displayed a submicron mean fiber diameter (PDS = 689 ± 312 nm and TAP-mimic = 718 ± 125 nm). Overall, TAP-mimic scaffolds showed significantly (P ≤ .040) lower mechanical properties than PDS. Within the first 24 hours, a burst release for all drugs was seen. A sustained maintenance of metronidazole and ciprofloxacin was observed over 4 weeks, but not for minocycline. Confocal laser scanning microscopy demonstrated complete elimination of all viable bacteria exposed to the TAP solution. Meanwhile, TAP-mimic scaffolds led to a significant (P mimic scaffolds hold significant potential in the eradication/elimination of bacterial biofilm, a critical step in regenerative endodontics. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

In vitro study of 3D PLGA/n-HAp/β-TCP composite scaffolds with etched oxygen plasma surface modification in bone tissue engineering

Energy Technology Data Exchange (ETDEWEB)

Roh, Hee-Sang [Department of Dental Materials, School of Dentistry, Chosun University, 309 Pilmun-daero, Dong-gu, Gwangju 61452 (Korea, Republic of); Jung, Sang-Chul [Department of Environmental Engineering, Sunchon National University, 255 Jungang-ro, Sunchon 57922 (Korea, Republic of); Kook, Min-Suk [Department of Oral and Maxillofacial Surgery, School of Dentistry, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 61186 (Korea, Republic of); Kim, Byung-Hoon, E-mail: kim5055@chosun.ac.kr [Department of Dental Materials, School of Dentistry, Chosun University, 309 Pilmun-daero, Dong-gu, Gwangju 61452 (Korea, Republic of)

2016-12-01

Highlights: • PLGA and PLGA/n-HAp/β-TCP scaffolds were successfully fabricated by 3D printing. • Oxygen plasma etching increases the wettability and surface roughness. • Bioceramics and oxygen plasma etching and could be used to improve the cell affinity. - Abstract: Three-dimensional (3D) scaffolds have many advantageous properties for bone tissue engineering application, due to its controllable properties such as pore size, structural shape and interconnectivity. In this study, effects on oxygen plasma surface modification and adding of nano-hydroxyapatite (n-HAp) and β-tricalcium phosphate (β-TCP) on the 3D PLGA/n-HAp/β-TCP scaffolds for improving preosteoblast cell (MC3T3-E1) adhesion, proliferation and differentiation were investigated. The 3D PLGA/n-HAp/β-TCP scaffolds were fabricated by 3D Bio-Extruder equipment. The 3D scaffolds were prepared with 0°/90° architecture and pore size of approximately 300 μm. In addition 3D scaffolds surface were etched by oxygen plasma to enhance the hydrophilic property and surface roughness. After oxygen plasma treatment, the surface chemistry and morphology were investigated by Fourier transform infrared spectroscopy, scanning electron microscopy, and atomic force microscopy. And also hydrophilic property was measured by contact angle. The MC3T3-E1 cell proliferation and differentiation were investigated by MTT assay and ALP activity. In present work, the 3D PLGA/HAp/beta-TCP composite scaffold with suitable structure for the growth of osteoblast cells was successfully fabricated by 3D rapid prototyping technique. The surface hydrophilicity and roughness of 3D scaffold increased by oxygen plasma treatment had a positive effect on cell adhesion, proliferation, and differentiation. Furthermore, the differentiation of MC3T3-E1 cell was significantly enhanced by adding of n-HAp and β-TCP on 3D PLGA scaffold. As a result, combination of bioceramics and oxygen plasma treatment showed a synergistic effect on

SHOP: scaffold hopping by GRID-based similarity searches

DEFF Research Database (Denmark)

Bergmann, Rikke; Linusson, Anna; Zamora, Ismael

2007-01-01

A new GRID-based method for scaffold hopping (SHOP) is presented. In a fully automatic manner, scaffolds were identified in a database based on three types of 3D-descriptors. SHOP's ability to recover scaffolds was assessed and validated by searching a database spiked with fragments of known...... scaffolds were in the 31 top-ranked scaffolds. SHOP also identified new scaffolds with substantially different chemotypes from the queries. Docking analysis indicated that the new scaffolds would have similar binding modes to those of the respective query scaffolds observed in X-ray structures...

3-D loaded scaffolds obtained by supercritical CO2 assisted process

Science.gov (United States)

Cardea, S.; Reverchon, E.

2014-08-01

In this work, a supercritical CO2 (SC-CO2) drying process for the formation of 3-D PVDF-HFP loaded scaffolds was tested. Experiments at pressures ranging between 150 and 250 bar and at temperatures ranging between 35 and 55°C were performed. The PVDF-HFP- acetone-ethanol solution at 15% w/w polymer was selected as the base case. The drug (amoxicillin) concentration was varied from 20 to 30% w/w with respect to PVDF-HFP. SC- CO2 drying process was confirmed to be a valid alternative to generate loaded structures; indeed, scaffolds characterized by nanometric networks (with mean pore diameter of about 300 nm) with a homogeneous drug distribution were obtained. Drug controlled release experiments were also performed and a quasi-zero order release kinetic was observed.

Study the bonding mechanism of binders on hydroxyapatite surface and mechanical properties for 3DP fabrication bone scaffolds.

Science.gov (United States)

Wei, Qinghua; Wang, Yanen; Li, Xinpei; Yang, Mingming; Chai, Weihong; Wang, Kai; zhang, Yingfeng

2016-04-01

In 3DP fabricating artificial bone scaffolds process, the interaction mechanism between binder and bioceramics power determines the microstructure and macro mechanical properties of Hydroxyapatite (HA) bone scaffold. In this study, we applied Molecular Dynamics (MD) methods to investigating the bonding mechanism and essence of binders on the HA crystallographic planes for 3DP fabrication bone scaffolds. The cohesive energy densities of binders and the binding energies, PCFs g(r), mechanical properties of binder/HA interaction models were analyzed through the MD simulation. Additionally, we prepared the HA bone scaffold specimens with different glues by 3DP additive manufacturing, and tested their mechanical properties by the electronic universal testing machine. The simulation results revealed that the relationship of the binding energies between binders and HA surface is consistent with the cohesive energy densities of binders, which is PAM/HA>PVA/HA>PVP/HA. The PCFs g(r) indicated that their interfacial interactions mainly attribute to the ionic bonds and hydrogen bonds which formed between the polar atoms, functional groups in binder polymer and the Ca, -OH in HA. The results of mechanical experiments verified the relationship of Young׳s modulus for three interaction models in simulation, which is PVA/HA>PAM/HA>PVP/HA. But the trend of compressive strength is PAM/HA>PVA/HA>PVP/HA, this is consistent with the binding energies of simulation. Therefore, the Young׳s modulus of bone scaffolds are limited by the Young׳s modulus of binders, and the compressive strength is mainly decided by the viscosity of binder. Finally, the major reasons for differences in mechanical properties between simulation and experiment were found, the space among HA pellets and the incomplete infiltration of glue were the main reasons influencing the mechanical properties of 3DP fabrication HA bone scaffolds. These results provide useful information in choosing binder for 3DP fabrication

Fabrication of 3D porous SF/β-TCP hybrid scaffolds for bone tissue reconstruction.

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Park, Hyun Jung; Min, Kyung Dan; Lee, Min Chae; Kim, Soo Hyeon; Lee, Ok Joo; Ju, Hyung Woo; Moon, Bo Mi; Lee, Jung Min; Park, Ye Ri; Kim, Dong Wook; Jeong, Ju Yeon; Park, Chan Hum

2016-07-01

Bio-ceramic is a biomaterial actively studied in the field of bone tissue engineering. But, only certain ceramic materials can resolve the corrosion problem and possess the biological affinity of conventional metal biomaterials. Therefore, the recent development of composites of hybrid composites and polymers has been widely studied. In this study, we aimed to select the best scaffold of silk fibroin and β-TCP hybrid for bone tissue engineering. We fabricated three groups of scaffold such as SF (silk fibroin scaffold), GS (silk fibroin/small granule size of β-TCP scaffold) and GM (silk fibroin/medium granule size of β-TCP scaffold), and we compared the characteristics of each group. During characterization of the scaffold, we used scanning electron microscopy (SEM) and a Fourier transform infrared spectroscopy (FTIR) for structural analysis. We compared the physiological properties of the scaffold regarding the swelling ratio, water uptake and porosity. To evaluate the mechanical properties, we examined the compressive strength of the scaffold. During in vitro testing, we evaluated cell attachment and cell proliferation (CCK-8). Finally, we confirmed in vivo new bone regeneration from the implanted scaffolds using histological staining and micro-CT. From these evaluations, the fabricated scaffold demonstrated high porosity with good inter-pore connectivity, showed good biocompatibility and high compressive strength and modulus. In particular, the present study indicates that the GM scaffold using β-TCP accelerates new bone regeneration of implanted scaffolds. Accordingly, our scaffold is expected to act a useful application in the field of bone tissue engineering. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1779-1787, 2016. © 2016 Wiley Periodicals, Inc.

Channeled Scaffolds for Engineering Myocardium with Mechanical Stimulation

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Zhang, Ting; Wan, Leo Q.; Xiong, Zhuo; Marsano, Anna; Maidhof, Robert; Park, Miri; Yan, Yongnian; Vunjak-Novakovic, Gordana

2011-01-01

The characteristics of the matrix (composition, structure, mechanical properties) and external culture environment (pulsatile perfusion, physical stimulation) are critically important for engineering functional myocardial tissue. We report the development of chitosan-collagen scaffolds with micro-pores and an array of parallel channels (~200 μm in diameter) that were specifically designed for cardiac tissue engineering with mechanical stimulation. The scaffolds were designed to have the structural and mechanical properties similar to those of the native human heart matrix. Scaffolds were seeded with neonatal rat heart cells and subjected to dynamic tensile stretch using a custom-designed bioreactor. The channels enhanced oxygen transport and facilitated the establishment of cell connections within the construct. The myocardial patches (14 mm in diameter, 1–2 mm thick) consisted of metabolically active cells and started to contract synchronously after 3 days of culture. Mechanical stimulation with high tensile stresses promoted cell alignment, elongation, and the expression of connexin-43 (Cx-43). This study confirms the importance of scaffold design and mechanical stimulation for the formation of contractile cardiac constructs. PMID:22081518

Construction of engineering adipose-like tissue in vivo utilizing human insulin gene-modified umbilical cord mesenchymal stromal cells with silk fibroin 3D scaffolds.

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Li, Shi-Long; Liu, Yi; Hui, Ling

2015-12-01

We evaluated the use of a combination of human insulin gene-modified umbilical cord mesenchymal stromal cells (hUMSCs) with silk fibroin 3D scaffolds for adipose tissue engineering. In this study hUMSCs were isolated and cultured. HUMSCs infected with Ade-insulin-EGFP were seeded in fibroin 3D scaffolds with uniform 50-60 µm pore size. Silk fibroin scaffolds with untransfected hUMSCs were used as control. They were cultured for 4 days in adipogenic medium and transplanted under the dorsal skins of female Wistar rats after the hUMSCs had been labelled with chloromethylbenzamido-1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (CM-Dil). Macroscopical impression, fluorescence observation, histology and SEM were used for assessment after transplantation at 8 and 12 weeks. Macroscopically, newly formed adipose tissue was observed in the experimental group and control group after 8 and 12 weeks. Fluorescence observation supported that the formed adipose tissue originated from seeded hUMSCs rather than from possible infiltrating perivascular tissue. Oil red O staining of newly formed tissue showed that there was substantially more tissue regeneration in the experimental group than in the control group. SEM showed that experimental group cells had more fat-like cells, whose volume was larger than that of the control group, and degradation of the silk fibroin scaffold was greater under SEM observation. This study provides significant evidence that hUMSCs transfected by adenovirus vector have good compatibility with silk fibroin scaffold, and adenoviral transfection of the human insulin gene can be used for the construction of tissue-engineered adipose. Copyright © 2013 John Wiley & Sons, Ltd.

3D- Printed Poly(ε-caprolactone) Scaffold Integrated with Cell-laden Chitosan Hydrogels for Bone Tissue Engineering.

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Dong, Liang; Wang, Shao-Jie; Zhao, Xin-Rong; Zhu, Yu-Fang; Yu, Jia-Kuo

2017-10-17

Synthetic polymeric scaffolds are commonly used in bone tissue engineering (BTE) due to their biocompatibility and adequate mechanical properties. However, their hydrophobicity and the lack of specific cell recognition sites confined their practical application. In this study, to improve the cell seeding efficiency and osteoinductivity, an injectable thermo-sensitive chitosan hydrogel (CSG) was incorporated into a 3D-printed poly(ε-caprolactone) (PCL) scaffold to form a hybrid scaffold. To demonstrate the feasibility of this hybrid system for BTE application, rabbit bone marrow mesenchymal stem cells (BMMSCs) and bone morphogenetic protein-2 (BMP-2) were encapsulated in CSG. Pure PCL scaffolds were used as controls. Cell proliferation and viability were investigated. Osteogenic gene expressions of BMMSCs in various scaffolds were determined with reverse transcription polymerase chain reaction (RT-PCR). Growth factor releasing profile and mechanical tests were performed. CCK-8 assay confirmed greater cell retention and proliferation in chitosan and hybrid groups. Confocal microscopy showed even distribution of cells in the hybrid system. After 2-week osteogenic culture in vitro, BMMSCs in hybrid and chitosan scaffolds showed stronger osteogenesis and bone-matrix formation. To conclude, chitosan/PCL hybrid scaffolds are a favorable platform for BTE due to its capacity to carry cells and drugs, and excellent mechanical strength.

Scaffolding proteins: not such innocent bystanders.

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Smith, F Donelson; Scott, John D

2013-06-17

Sequential transfer of information from one enzyme to the next within the confines of a protein kinase scaffold enhances signal transduction. Though frequently considered to be inert organizational elements, two recent reports implicate kinase-scaffolding proteins as active participants in signal relay. Copyright © 2013 Elsevier Ltd. All rights reserved.

Production of new 3D scaffolds for bone tissue regeneration by rapid prototyping.

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Fradique, R; Correia, T R; Miguel, S P; de Sá, K D; Figueira, D R; Mendonça, A G; Correia, I J

2016-04-01

The incidence of bone disorders, whether due to trauma or pathology, has been trending upward with the aging of the worldwide population. The currently available treatments for bone injuries are rather limited, involving mainly bone grafts and implants. A particularly promising approach for bone regeneration uses rapid prototyping (RP) technologies to produce 3D scaffolds with highly controlled structure and orientation, based on computer-aided design models or medical data. Herein, tricalcium phosphate (TCP)/alginate scaffolds were produced using RP and subsequently their physicochemical, mechanical and biological properties were characterized. The results showed that 60/40 of TCP and alginate formulation was able to match the compression and present a similar Young modulus to that of trabecular bone while presenting an adequate biocompatibility. Moreover, the biomineralization ability, roughness and macro and microporosity of scaffolds allowed cell anchoring and proliferation at their surface, as well as cell migration to its interior, processes that are fundamental for osteointegration and bone regeneration.

Design and synthesis of novel insecticides based on the serotonergic ligand 1-[(4-aminophenyl)ethyl]-4-[3-(trifluoromethyl)phenyl]piperazine (PAPP).

Science.gov (United States)

Cai, Mingyi; Li, Zhong; Fan, Feng; Huang, Qingchun; Shao, Xusheng; Song, Gonghua

2010-03-10

1-[(4-Aminophenyl)ethyl]-4-[3-(trifluoromethyl)phenyl]piperazine (PAPP) is a 5-HT(1A) agonist and was reported to display high affinity for serotonin (5-HT) receptor from the parasitic nematode Haemonchus contortus . The present investigation explored the possibility of using PAPP as a lead compound of new insecticides with novel mode of action. On the basis of the PAPP scaffold, a series of 1-arylmethyl-4-[(trifluoromethyl)pyridin-2-yl]piperazine derivatives were designed, synthesized, and evaluated for biological activities against the armyworm Pseudaletia separata (Walker). Bioassays showed that most of the target compounds displayed certain growth-inhibiting activities or larvicidal activities against armyworm. The quantitative structure-activity relationship (QSAR) for growth-inhibiting activities was also analyzed and established.

Rheological, biocompatibility and osteogenesis assessment of fish collagen scaffold for bone tissue engineering.

Science.gov (United States)

Elango, Jeevithan; Zhang, Jingyi; Bao, Bin; Palaniyandi, Krishnamoorthy; Wang, Shujun; Wenhui, Wu; Robinson, Jeya Shakila

2016-10-01

In the present investigation, an attempt was made to find an alternative to mammalian collagen with better osteogenesis ability. Three types of collagen scaffolds - collagen, collagen-chitosan (CCH), and collagen-hydroxyapatite (CHA) - were prepared from the cartilage of Blue shark and investigated for their physico-functional and mechanical properties in relation to biocompatibility and osteogenesis. CCH scaffold was superior with pH 4.5-4.9 and viscosity 9.7-10.9cP. Notably, addition of chitosan and HA (hydroxyapatite) improved the stiffness (11-23MPa) and degradation rate but lowered the water binding capacity and porosity of the scaffold. Interestingly, CCH scaffolds remained for 3days before complete in-vitro biodegradation. The decreased amount of viable T-cells and higher level of FAS/APO-1 were substantiated the biocompatibility properties of prepared collagen scaffolds. Osteogenesis study revealed that the addition of CH and HA in both fish and mammalian collagen scaffolds could efficiently promote osteoblast cell formation. The ALP activity was significantly high in CHA scaffold-treated osteoblast cells, which suggests an enhanced bone-healing process. Therefore, the present study concludes that the composite scaffolds prepared from fish collagen with higher stiffness, lower biodegradation rate, better biocompatible, and osteogenesis properties were suitable biomaterial for a bone tissue engineering application as an alternative to mammalian collagen scaffolds. Copyright © 2016 Elsevier B.V. All rights reserved.

Polycaprolactone nanofiber interspersed collagen type-I scaffold for bone regeneration: a unique injectable osteogenic scaffold

International Nuclear Information System (INIS)

Baylan, Nuray; Ditto, Maggie; Lawrence, Joseph G; Yildirim-Ayan, Eda; Bhat, Samerna; Lecka-Czernik, Beata

2013-01-01

There is an increasing demand for an injectable cell coupled three-dimensional (3D) scaffold to be used as bone fracture augmentation material. To address this demand, a novel injectable osteogenic scaffold called PN-COL was developed using cells, a natural polymer (collagen type-I), and a synthetic polymer (polycaprolactone (PCL)). The injectable nanofibrous PN-COL is created by interspersing PCL nanofibers within pre-osteoblast cell embedded collagen type-I. This simple yet novel and powerful approach provides a great benefit as an injectable bone scaffold over other non-living bone fracture stabilization polymers, such as polymethylmethacrylate and calcium content resin-based materials. The advantages of injectability and the biomimicry of collagen was coupled with the structural support of PCL nanofibers, to create cell encapsulated injectable 3D bone scaffolds with intricate porous internal architecture and high osteoconductivity. The effects of PCL nanofiber inclusion within the cell encapsulated collagen matrix has been evaluated for scaffold size retention and osteocompatibility, as well as for MC3T3-E1 cells osteogenic activity. The structural analysis of novel bioactive material proved that the material is chemically stable enough in an aqueous solution for an extended period of time without using crosslinking reagents, but it is also viscous enough to be injected through a syringe needle. Data from long-term in vitro proliferation and differentiation data suggests that novel PN-COL scaffolds promote the osteoblast proliferation, phenotype expression, and formation of mineralized matrix. This study demonstrates for the first time the feasibility of creating a structurally competent, injectable, cell embedded bone tissue scaffold. Furthermore, the results demonstrate the advantages of mimicking the hierarchical architecture of native bone with nano- and micro-size formation through introducing PCL nanofibers within macron-size collagen fibers and in

Prevascularization of 3D printed bone scaffolds by bioactive hydrogels and cell co-culture.

Science.gov (United States)

Kuss, Mitchell A; Wu, Shaohua; Wang, Ying; Untrauer, Jason B; Li, Wenlong; Lim, Jung Yul; Duan, Bin

2017-09-13

Vascularization is a fundamental prerequisite for large bone construct development and remains one of the main challenges of bone tissue engineering. Our current study presents the combination of 3D printing technique with a hydrogel-based prevascularization strategy to generate prevascularized bone constructs. Human adipose derived mesenchymal stem cells (ADMSC) and human umbilical vein endothelial cells (HUVEC) were encapsulated within our bioactive hydrogels, and the effects of culture conditions on in vitro vascularization were determined. We further generated composite constructs by forming 3D printed polycaprolactone/hydroxyapatite scaffolds coated with cell-laden hydrogels and determined how the co-culture affected vascularization and osteogenesis. It was demonstrated that 3D co-cultured ADMSC-HUVEC generated capillary-like networks within the porous 3D printed scaffold. The co-culture systems promoted in vitro vascularization, but had no significant effects on osteogenesis. The prevascularized constructs were subcutaneously implanted into nude mice to evaluate the in vivo vascularization capacity and the functionality of engineered vessels. The hydrogel systems facilitated microvessel and lumen formation and promoted anastomosis of vascular networks of human origin with host murine vasculature. These findings demonstrate the potential of prevascularized 3D printed scaffolds with anatomical shape for the healing of larger bone defects. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2017. © 2017 Wiley Periodicals, Inc.

Bio-functionalized PCL nanofibrous scaffolds for nerve tissue engineering

International Nuclear Information System (INIS)

Ghasemi-Mobarakeh, Laleh; Prabhakaran, Molamma P.; Morshed, Mohammad; Nasr-Esfahani, Mohammad Hossein; Ramakrishna, S.

2010-01-01

Surface properties of scaffolds such as hydrophilicity and the presence of functional groups on the surface of scaffolds play a key role in cell adhesion, proliferation and migration. Different modification methods for hydrophilicity improvement and introduction of functional groups on the surface of scaffolds have been carried out on synthetic biodegradable polymers, for tissue engineering applications. In this study, alkaline hydrolysis of poly (ε-caprolactone) (PCL) nanofibrous scaffolds was carried out for different time periods (1 h, 4 h and 12 h) to increase the hydrophilicity of the scaffolds. The formation of reactive groups resulting from alkaline hydrolysis provides opportunities for further surface functionalization of PCL nanofibrous scaffolds. Matrigel was attached covalently on the surface of an optimized 4 h hydrolyzed PCL nanofibrous scaffolds and additionally the fabrication of blended PCL/matrigel nanofibrous scaffolds was carried out. Chemical and mechanical characterization of nanofibrous scaffolds were evaluated using attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, contact angle, scanning electron microscopy (SEM) and tensile measurement. In vitro cell adhesion and proliferation study was carried out after seeding nerve precursor cells (NPCs) on different scaffolds. Results of cell proliferation assay and SEM studies showed that the covalently functionalized PCL/matrigel nanofibrous scaffolds promote the proliferation and neurite outgrowth of NPCs compared to PCL and hydrolyzed PCL nanofibrous scaffolds, providing suitable substrates for nerve tissue engineering.

3D Printed, PVA–PAA Hydrogel Loaded-Polycaprolactone Scaffold for the Delivery of Hydrophilic In-Situ Formed Sodium Indomethacin

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Mershen Govender

2018-06-01

Full Text Available 3D printed polycaprolactone (PCL-blended scaffolds have been designed, prepared, and evaluated in vitro in this study prior to the incorporation of a polyvinyl alcohol–polyacrylic acid (PVA–PAA hydrogel for the delivery of in situ-formed sodium indomethacin. The prepared PCL–PVA–PAA scaffold is proposed as a potential structural support system for load-bearing tissue damage where inflammation is prevalent. Uniaxial strain testing of the PCL-blended scaffolds were undertaken to determine the scaffold’s resistance to strain in addition to its thermal, structural, and porosimetric properties. The viscoelastic properties of the incorporated PVA–PAA hydrogel has also been determined, as well as the drug release profile of the PCL–PVA–PAA scaffold. Results of these analyses noted the structural strength, thermal stability, and porosimetric properties of the scaffold, as well as the ability of the PCL–PVA–PAA scaffold to deliver sodium indomethacin in simulated physiological conditions of pH and temperature. The results of this study therefore highlight the successful design, fabrication, and in vitro evaluation of a 3D printed polymeric strain-resistant supportive platform for the delivery of sodium indomethacin.

Design and characterization of a biodegradable composite scaffold for ligament tissue engineering.

Science.gov (United States)

Hayami, James W S; Surrao, Denver C; Waldman, Stephen D; Amsden, Brian G

2010-03-15

Herein we report on the development and characterization of a biodegradable composite scaffold for ligament tissue engineering based on the fundamental morphological features of the native ligament. An aligned fibrous component was used to mimic the fibrous collagen network and a hydrogel component to mimic the proteoglycan-water matrix of the ligament. The composite scaffold was constructed from cell-adherent, base-etched, electrospun poly(epsilon-caprolactone-co-D,L-lactide) (PCLDLLA) fibers embedded in a noncell-adherent photocrosslinked N-methacrylated glycol chitosan (MGC) hydrogel seeded with primary ligament fibroblasts. Base etching improved cellular adhesion to the PCLDLLA material. Cells within the MGC hydrogel remained viable (72 +/- 4%) during the 4-week culture period. Immunohistochemistry staining revealed ligament ECM markers collagen type I, collagen type III, and decorin organizing and accumulating along the PCLDLLA fibers within the composite scaffolds. On the basis of these results, it was determined that the composite scaffold design was a viable alternative to the current approaches used for ligament tissue engineering and merits further study. (c) 2009 Wiley Periodicals, Inc.

The osteogenic potential of mesoporous bioglasses/silk and non-mesoporous bioglasses/silk scaffolds in ovariectomized rats: in vitro and in vivo evaluation.

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Ning Cheng

Full Text Available Silk-based scaffolds have been introduced to bone tissue regeneration for years, however, their local therapeutic efficiency in bone metabolic disease condition has been seldom reported. According to our previous report, mesoporous bioactive glass (MBG/silk scaffolds exhibits superior in vitro bioactivity and in vivo osteogenic properties compared to non-mesoporous bioactive glass (BG/silk scaffolds, but no information could be found about their efficiency in osteoporotic (OVX environment. This study investigated a biomaterial-based approach for improving MSCs behavior in vitro, and accelerating OVX defect healing by using 3D BG/silk and MBG/silk scaffolds, and pure silk scaffolds as control. The results of SEM, CCK-8 assay and quantitative ALP activity showed that MBG/silk scaffolds can improve attachment, proliferation and osteogenic differentiation of both O-MSCs and sham control. In vivo therapeutic efficiency was evaluated by μCT analysis, hematoxylin and eosin staining, safranin O staining and tartrate-resistant acid phosphatase, indicating accelerated bone formation with compatible scaffold degradation and reduced osteoclastic response of defect healing in OVX rats after 2 and 4 weeks treatment, with a rank order of MBG/silk > BG/silk > silk group. Immunohistochemical markers of COL I, OPN, BSP and OCN also revealed that MBG/silk scaffolds can better induce accelerated collagen and non-collagen matrix production. The findings of this study suggest that MBG/silk scaffolds provide a better environment for cell attachment, proliferation and differentiation, and act as potential substitute for treating local osteoporotic defects.

Integrating biologically inspired nanomaterials and table-top stereolithography for 3D printed biomimetic osteochondral scaffolds

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Castro, Nathan J.; O'Brien, Joseph; Zhang, Lijie Grace

2015-08-01

The osteochondral interface of an arthritic joint is notoriously difficult to regenerate due to its extremely poor regenerative capacity and complex stratified architecture. Native osteochondral tissue extracellular matrix is composed of numerous nanoscale organic and inorganic constituents. Although various tissue engineering strategies exist in addressing osteochondral defects, limitations persist with regards to tissue scaffolding which exhibit biomimetic cues at the nano to micro scale. In an effort to address this, the current work focused on 3D printing biomimetic nanocomposite scaffolds for improved osteochondral tissue regeneration. For this purpose, two biologically-inspired nanomaterials have been synthesized consisting of (1) osteoconductive nanocrystalline hydroxyapatite (nHA) (primary inorganic component of bone) and (2) core-shell poly(lactic-co-glycolic) acid (PLGA) nanospheres encapsulated with chondrogenic transforming growth-factor β1 (TGF-β1) for sustained delivery. Then, a novel table-top stereolithography 3D printer and the nano-ink (i.e., nHA + nanosphere + hydrogel) were employed to fabricate a porous and highly interconnected osteochondral scaffold with hierarchical nano-to-micro structure and spatiotemporal bioactive factor gradients. Our results showed that human bone marrow-derived mesenchymal stem cell adhesion, proliferation, and osteochondral differentiation were greatly improved in the biomimetic graded 3D printed osteochondral construct in vitro. The current work served to illustrate the efficacy of the nano-ink and current 3D printing technology for efficient fabrication of a novel nanocomposite hydrogel scaffold. In addition, tissue-specific growth factors illustrated a synergistic effect leading to increased cell adhesion and directed stem cell differentiation.

Conducting Polymer Scaffolds for Hosting and Monitoring 3D Cell Culture

KAUST Repository

Inal, Sahika; Hama, Adel; Ferro, Magali; Pitsalidis, Charalampos; Oziat, Julie; Iandolo, Donata; Pappa, Anna-Maria; Hadida, Mikhael; Huerta, Miriam; Marchat, David; Mailley, Pascal; Owens, Ró isí n M.

2017-01-01

to their biocompatibility and tissue-like elasticity, which can be manipulated by inclusion of biopolymers such as collagen. Integration of a media perfusion tube inside the scaffold enables homogenous cell spreading and fluid transport throughout the scaffold, ensuring

Poly(dopamine) coating of 3D printed poly(lactic acid) scaffolds for bone tissue engineering.

Science.gov (United States)

Kao, Chia-Tze; Lin, Chi-Chang; Chen, Yi-Wen; Yeh, Chia-Hung; Fang, Hsin-Yuan; Shie, Ming-You

2015-11-01

3D printing is a versatile technique to generate large quantities of a wide variety of shapes and sizes of polymer. The aim of this study is to develop functionalized 3D printed poly(lactic acid) (PLA) scaffolds and use a mussel-inspired surface coating to regulate cell adhesion, proliferation and differentiation of human adipose-derived stem cells (hADSCs). We prepared PLA 3D scaffolds coated with polydopamine (PDA). The chemical composition and surface properties of PDA/PLA were characterized by XPS. PDA/PLA modulated hADSCs' responses in several ways. Firstly, adhesion and proliferation, and cell cycle of hADSCs cultured on PDA/PLA were significantly enhanced relative to those on PLA. In addition, the collagen I secreted from cells was increased and promoted cell attachment and cell cycle progression were depended on the PDA content. In osteogenesis assay, the ALP activity and osteocalcin of hADSCs cultured on PDA/PLA were significantly higher than seen in those cultured on pure PLA scaffolds. Moreover, hADSCs cultured on PDA/PLA showed up-regulation of the ang-1 and vWF proteins associated with angiogenic differentiation. Our results demonstrate that the bio-inspired coating synthetic PLA polymer can be used as a simple technique to render the surfaces of synthetic scaffolds active, thus enabling them to direct the specific responses of hADSCs. Copyright © 2015 Elsevier B.V. All rights reserved.

Microscale architecture in biomaterial scaffolds for spatial control of neural cell behavior

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Meco, Edi; Lampe, Kyle J.

2018-02-01

Biomaterial scaffolds mimic aspects of the native central nervous system (CNS) extracellular matrix (ECM) and have been extensively utilized to influence neural cell (NC) behavior in in vitro and in vivo settings. These biomimetic scaffolds support NC cultures, can direct the differentiation of NCs, and have recapitulated some native NC behavior in an in vitro setting. However, NC transplant therapies and treatments used in animal models of CNS disease and injury have not fully restored functionality. The observed lack of functional recovery occurs despite improvements in transplanted NC viability when incorporating biomaterial scaffolds and the potential of NC to replace damaged native cells. The behavior of NCs within biomaterial scaffolds must be directed in order to improve the efficacy of transplant therapies and treatments. Biomaterial scaffold topography and imbedded bioactive cues, designed at the microscale level, can alter NC phenotype, direct migration, and differentiation. Microscale patterning in biomaterial scaffolds for spatial control of NC behavior has enhanced the capabilities of in vitro models to capture properties of the native CNS tissue ECM. Patterning techniques such as lithography, electrospinning and 3D bioprinting can be employed to design the microscale architecture of biomaterial scaffolds. Here, the progress and challenges of the prevalent biomaterial patterning techniques of lithography, electrospinning, and 3D bioprinting are reported. This review analyzes NC behavioral response to specific microscale topographical patterns and spatially organized bioactive cues.

Mechano growth factor (MGF) and transforming growth factor (TGF)-β3 functionalized silk scaffolds enhance articular hyaline cartilage regeneration in rabbit model.

Science.gov (United States)

Luo, Ziwei; Jiang, Li; Xu, Yan; Li, Haibin; Xu, Wei; Wu, Shuangchi; Wang, Yuanliang; Tang, Zhenyu; Lv, Yonggang; Yang, Li

2015-06-01

Damaged cartilage has poor self-healing ability and usually progresses to scar or fibrocartilaginous tissue, and finally degenerates to osteoarthritis (OA). Here we demonstrated that one of alternative isoforms of IGF-1, mechano growth factor (MGF) acted synergistically with transforming growth factor β3 (TGF-β3) embedded in silk fibroin scaffolds to induce chemotactic homing and chondrogenic differentiation of mesenchymal stem cells (MSCs). Combination of MGF and TGF-β3 significantly increased cell recruitment up to 1.8 times and 2 times higher than TGF-β3 did in vitro and in vivo. Moreover, MGF increased Collagen II and aggrecan secretion of TGF-β3 induced hMSCs chondrogenesis, but decreased Collagen I in vitro. Silk fibroin (SF) scaffolds have been widely used for tissue engineering, and we showed that methanol treated pured SF scaffolds were porous, similar to compressive module of native cartilage, slow degradation rate and excellent drug released curves. At 7 days after subcutaneous implantation, TGF-β3 and MGF functionalized silk fibroin scaffolds (STM) recruited more CD29+/CD44+cells (Pcartilage-like extracellular matrix and less fibrillar collagen were detected in STM scaffolds than that in TGF-β3 modified scaffolds (ST) at 2 months after subcutaneous implantation. When implanted into articular joints in a rabbit osteochondral defect model, STM scaffolds showed the best integration into host tissues, similar architecture and collagen organization to native hyaline cartilage, as evidenced by immunostaining of aggrecan, collagen II and collagen I, as well as Safranin O and Masson's trichrome staining, and histological evalution based on the modified O'Driscoll histological scoring system (Pcartilage regeneration. This study demonstrated that TGF-β3 and MGF functionalized silk fibroin scaffolds enhanced endogenous stem cell recruitment and facilitated in situ articular cartilage regeneration, thus providing a novel strategy for cartilage repair

3D nanocomposite chitosan/bioactive glass scaffolds obtained using two different routes: an evaluation of the porous structure and mechanical properties

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Elke M. F. Lemos

2016-05-01

Full Text Available Porous synthetic substrates are developed through tissue engineering technologies to grow new tissue, restoring the function of tissue or an organ. For bone regeneration, these scaffolds must support the dynamic load exerted on this tissue, achieved primarily by increasing their compression strength, as established in the literature. The aim of this paper was to incorporate an inorganic composite bioactive glass (60%SiO2 - 36%CaO - 4%P2O5 as a reinforcing agent in mechanical 3D scaffolds that must remain porous. Two strategies were adopted: a co-precipitation method to obtain a nanoparticulate dispersion of bioactive glass (BGNP and a sol-gel method to combine a bioactive glass solution (BG with a previously prepared chitosan polymer solution. Moreover, a lyophilization process was also used, generating highly porous scaffolds. Various aspects of the scaffold were evaluated, including the morphology, orientation and size of the pores, and mechanical strength, as obtained using the two synthetic methods. The data for compressive strength revealed increased strength after the incorporation of bioactive glass, which was more pronounced when utilizing the nanoscale bioactive glass.

Thermogel-Coated Poly(ε-Caprolactone Composite Scaffold for Enhanced Cartilage Tissue Engineering