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Redolfi Riva E, Özkan M, Contreras E, Pawar S, Zinno C, Escarda-Castro E, Kim J, Wieringa P, Stellacci F, Micera S, Navarro X. Beyond the limiting gap length: peripheral nerve regeneration through implantable nerve guidance conduits. Biomater Sci 2024; 12:1371-1404. [PMID: 38363090 DOI: 10.1039/d3bm01163a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2024]
Abstract
Peripheral nerve damage results in the loss of sensorimotor and autonomic functions, which is a significant burden to patients. Furthermore, nerve injuries greater than the limiting gap length require surgical repair. Although autografts are the preferred clinical choice, their usage is impeded by their limited availability, dimensional mismatch, and the sacrifice of another functional donor nerve. Accordingly, nerve guidance conduits, which are tubular scaffolds engineered to provide a biomimetic environment for nerve regeneration, have emerged as alternatives to autografts. Consequently, a few nerve guidance conduits have received clinical approval for the repair of short-mid nerve gaps but failed to regenerate limiting gap damage, which represents the bottleneck of this technology. Thus, it is still necessary to optimize the morphology and constituent materials of conduits. This review summarizes the recent advances in nerve conduit technology. Several manufacturing techniques and conduit designs are discussed, with emphasis on the structural improvement of simple hollow tubes, additive manufacturing techniques, and decellularized grafts. The main objective of this review is to provide a critical overview of nerve guidance conduit technology to support regeneration in long nerve defects, promote future developments, and speed up its clinical translation as a reliable alternative to autografts.
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Affiliation(s)
- Eugenio Redolfi Riva
- The Biorobotic Institute, Scuola Superiore Sant'Anna, Piazza Martiri della Libertà 33, 56127 Pisa, Italy.
- Department of Excellence in Robotics & AI, Scuola Superiore Sant'Anna, Piazza Martiri della Libertà 33, 56127 Pisa, Italy
| | - Melis Özkan
- Institute of Materials, école Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
- Bertarelli Foundation Chair in Translational Neural Engineering, Center for Neuroprosthetics and Institute of Bioengineering, école Polytechnique Federale de Lausanne, Lausanne, Switzerland
| | - Estefania Contreras
- Integral Service for Laboratory Animals (SIAL), Faculty of Veterinary, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
- Department of Cell Biology, Physiology and Immunology, Institute of Neurosciences, Universitat Autònoma de Barcelona (UAB), 08193 Bellaterra, Spain.
| | - Sujeet Pawar
- Institute of Materials, école Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Ciro Zinno
- The Biorobotic Institute, Scuola Superiore Sant'Anna, Piazza Martiri della Libertà 33, 56127 Pisa, Italy.
- Department of Excellence in Robotics & AI, Scuola Superiore Sant'Anna, Piazza Martiri della Libertà 33, 56127 Pisa, Italy
| | - Enrique Escarda-Castro
- Complex Tissue Regeneration Department, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, Maastricht, The Netherlands
| | - Jaehyeon Kim
- Complex Tissue Regeneration Department, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, Maastricht, The Netherlands
| | - Paul Wieringa
- Complex Tissue Regeneration Department, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, Maastricht, The Netherlands
| | - Francesco Stellacci
- Institute of Materials, école Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
- Institute of Materials, Department of Bioengineering and Global Health Institute, École Polytechnique Fédérale de Lausanne (EPFL), Station 12, CH-1015 Lausanne, Switzerland
| | - Silvestro Micera
- The Biorobotic Institute, Scuola Superiore Sant'Anna, Piazza Martiri della Libertà 33, 56127 Pisa, Italy.
- Department of Excellence in Robotics & AI, Scuola Superiore Sant'Anna, Piazza Martiri della Libertà 33, 56127 Pisa, Italy
- Bertarelli Foundation Chair in Translational Neural Engineering, Center for Neuroprosthetics and Institute of Bioengineering, école Polytechnique Federale de Lausanne, Lausanne, Switzerland
| | - Xavier Navarro
- Department of Cell Biology, Physiology and Immunology, Institute of Neurosciences, Universitat Autònoma de Barcelona (UAB), 08193 Bellaterra, Spain.
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), 28031 Madrid, Spain
- Institute Guttmann Foundation, Hospital of Neurorehabilitation, Badalona, Spain
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2
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Yazdani N, Willits RK. Mimicking the neural stem cell niche: An engineer’s view of cell: material interactions. FRONTIERS IN CHEMICAL ENGINEERING 2023. [DOI: 10.3389/fceng.2022.1086099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Neural stem cells have attracted attention in recent years to treat neurodegeneration. There are two neurogenic regions in the brain where neural stem cells reside, one of which is called the subventricular zone (SVZ). The SVZ niche is a complicated microenvironment providing cues to regulate self-renewal and differentiation while maintaining the neural stem cell’s pool. Many scientists have spent years understanding the cellular and structural characteristics of the SVZ niche, both in homeostasis and pathological conditions. On the other hand, engineers focus primarily on designing platforms using the knowledge they acquire to understand the effect of individual factors on neural stem cell fate decisions. This review provides a general overview of what we know about the components of the SVZ niche, including the residing cells, extracellular matrix (ECM), growth factors, their interactions, and SVZ niche changes during aging and neurodegenerative diseases. Furthermore, an overview will be given on the biomaterials used to mimic neurogenic niche microenvironments and the design considerations applied to add bioactivity while meeting the structural requirements. Finally, it will discuss the potential gaps in mimicking the microenvironment.
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3
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Development and In Vitro Differentiation of Schwann Cells. Cells 2022; 11:cells11233753. [PMID: 36497014 PMCID: PMC9739763 DOI: 10.3390/cells11233753] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 11/16/2022] [Accepted: 11/22/2022] [Indexed: 11/25/2022] Open
Abstract
Schwann cells are glial cells of the peripheral nervous system. They exist in several subtypes and perform a variety of functions in nerves. Their derivation and culture in vitro are interesting for applications ranging from disease modeling to tissue engineering. Since primary human Schwann cells are challenging to obtain in large quantities, in vitro differentiation from other cell types presents an alternative. Here, we first review the current knowledge on the developmental signaling mechanisms that determine neural crest and Schwann cell differentiation in vivo. Next, an overview of studies on the in vitro differentiation of Schwann cells from multipotent stem cell sources is provided. The molecules frequently used in those protocols and their involvement in the relevant signaling pathways are put into context and discussed. Focusing on hiPSC- and hESC-based studies, different protocols are described and compared, regarding cell sources, differentiation methods, characterization of cells, and protocol efficiency. A brief insight into developments regarding the culture and differentiation of Schwann cells in 3D is given. In summary, this contribution provides an overview of the current resources and methods for the differentiation of Schwann cells, it supports the comparison and refinement of protocols and aids the choice of suitable methods for specific applications.
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4
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De S, Singh N. Advancements in Three Dimensional In-Vitro Cell Culture Models. CHEM REC 2022; 22:e202200058. [PMID: 35701102 DOI: 10.1002/tcr.202200058] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 05/26/2022] [Indexed: 12/27/2022]
Abstract
The scientific field is observing a gradual shift from monolayer cultures to three-dimensional (3D) models, as they give a more relevant data in pre-clinical stages. This review summarizes the major techniques and materials used to develop 3D platforms, especially for cancer. It also discusses the challenges and some unresolved issues of the field and highlights some techniques that have made it to the market.
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Affiliation(s)
- Shreemoyee De
- Centre for Biomedical Engineering, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, 110016, India
| | - Neetu Singh
- Centre for Biomedical Engineering, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, 110016, India.,Biomedical Engineering Unit, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, 110029, India
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5
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Oevreeide IH, Szydlak R, Luty M, Ahmed H, Prot V, Skallerud BH, Zemła J, Lekka M, Stokke BT. On the Determination of Mechanical Properties of Aqueous Microgels-Towards High-Throughput Characterization. Gels 2021; 7:64. [PMID: 34072792 PMCID: PMC8261632 DOI: 10.3390/gels7020064] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 05/21/2021] [Accepted: 05/25/2021] [Indexed: 12/15/2022] Open
Abstract
Aqueous microgels are distinct entities of soft matter with mechanical signatures that can be different from their macroscopic counterparts due to confinement effects in the preparation, inherently made to consist of more than one domain (Janus particles) or further processing by coating and change in the extent of crosslinking of the core. Motivated by the importance of the mechanical properties of such microgels from a fundamental point, but also related to numerous applications, we provide a perspective on the experimental strategies currently available and emerging tools being explored. Albeit all techniques in principle exploit enforcing stress and observing strain, the realization differs from directly, as, e.g., by atomic force microscope, to less evident in a fluid field combined with imaging by a high-speed camera in high-throughput strategies. Moreover, the accompanying analysis strategies also reflect such differences, and the level of detail that would be preferred for a comprehensive understanding of the microgel mechanical properties are not always implemented. Overall, the perspective is that current technologies have the capacity to provide detailed, nanoscopic mechanical characterization of microgels over an extended size range, to the high-throughput approaches providing distributions over the mechanical signatures, a feature not readily accessible by atomic force microscopy and micropipette aspiration.
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Affiliation(s)
- Ingrid Haga Oevreeide
- Biophysics and Medical Technology, Department of Physics, NTNU The Norwegian University of Science and Technology, NO-7491 Trondheim, Norway; (I.H.O.); (H.A.)
| | - Renata Szydlak
- Institute of Nuclear Physics, Polish Academy of Sciences, PL-31342 Krakow, Poland; (R.S.); (M.L.); (J.Z.)
| | - Marcin Luty
- Institute of Nuclear Physics, Polish Academy of Sciences, PL-31342 Krakow, Poland; (R.S.); (M.L.); (J.Z.)
| | - Husnain Ahmed
- Biophysics and Medical Technology, Department of Physics, NTNU The Norwegian University of Science and Technology, NO-7491 Trondheim, Norway; (I.H.O.); (H.A.)
| | - Victorien Prot
- Biomechanics, Department of Structural Engineering, NTNU The Norwegian University of Science and Technology, NO-7491 Trondheim, Norway; (V.P.); (B.H.S.)
| | - Bjørn Helge Skallerud
- Biomechanics, Department of Structural Engineering, NTNU The Norwegian University of Science and Technology, NO-7491 Trondheim, Norway; (V.P.); (B.H.S.)
| | - Joanna Zemła
- Institute of Nuclear Physics, Polish Academy of Sciences, PL-31342 Krakow, Poland; (R.S.); (M.L.); (J.Z.)
| | - Małgorzata Lekka
- Institute of Nuclear Physics, Polish Academy of Sciences, PL-31342 Krakow, Poland; (R.S.); (M.L.); (J.Z.)
| | - Bjørn Torger Stokke
- Biophysics and Medical Technology, Department of Physics, NTNU The Norwegian University of Science and Technology, NO-7491 Trondheim, Norway; (I.H.O.); (H.A.)
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6
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Xu Z, Orkwis JA, Harris GM. Cell Shape and Matrix Stiffness Impact Schwann Cell Plasticity via YAP/TAZ and Rho GTPases. Int J Mol Sci 2021; 22:ijms22094821. [PMID: 34062912 PMCID: PMC8124465 DOI: 10.3390/ijms22094821] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 04/27/2021] [Accepted: 04/28/2021] [Indexed: 01/01/2023] Open
Abstract
Schwann cells (SCs) are a highly plastic cell type capable of undergoing phenotypic changes following injury or disease. SCs are able to upregulate genes associated with nerve regeneration and ultimately achieve functional recovery. During the regeneration process, the extracellular matrix (ECM) and cell morphology play a cooperative, critical role in regulating SCs, and therefore highly impact nerve regeneration outcomes. However, the roles of the ECM and mechanotransduction relating to SC phenotype are largely unknown. Here, we describe the role that matrix stiffness and cell morphology play in SC phenotype specification via known mechanotransducers YAP/TAZ and RhoA. Using engineered microenvironments to precisely control ECM stiffness, cell shape, and cell spreading, we show that ECM stiffness and SC spreading downregulated SC regenerative associated proteins by the activation of RhoA and YAP/TAZ. Additionally, cell elongation promoted a distinct SC regenerative capacity by the upregulation of Rac1/MKK7/JNK, both necessary for the ECM and morphology changes found during nerve regeneration. These results confirm the role of ECM signaling in peripheral nerve regeneration as well as provide insight to the design of future biomaterials and cellular therapies for peripheral nerve regeneration.
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Affiliation(s)
- Zhenyuan Xu
- Department of Chemical and Environmental Engineering, University of Cincinnati, Cincinnati, OH 45221, USA; (Z.X.); (J.A.O.)
| | - Jacob A. Orkwis
- Department of Chemical and Environmental Engineering, University of Cincinnati, Cincinnati, OH 45221, USA; (Z.X.); (J.A.O.)
| | - Greg M. Harris
- Department of Chemical and Environmental Engineering, University of Cincinnati, Cincinnati, OH 45221, USA; (Z.X.); (J.A.O.)
- Department of Biomedical Engineering, University of Cincinnati, Cincinnati, OH 45221, USA
- Neuroscience Graduate Program, College of Medicine, University of Cincinnati, Cincinnati, OH 45267, USA
- Correspondence: ; Tel.: +1-(513)-556-4167
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7
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Aluri KC, Hossain MA, Kanetkar N, Miller BC, Dowgiallo MG, Sivasankar D, Sullivan MR, Manetsch R, Konry T, Ekenseair A, Agar JN. Cyclic Thiosulfinates as a Novel Class of Disulfide Cleavable Cross-Linkers for Rapid Hydrogel Synthesis. Bioconjug Chem 2021; 32:584-594. [PMID: 33606505 DOI: 10.1021/acs.bioconjchem.1c00049] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We recently reported that cyclic thiosulfinates are cysteine selective cross-linkers that avoid the "dead-end" modifications that contribute to other cross-linkers' toxicity. In this study, we generalize the chemistry of cyclic thiosulfinates to that of thiol selective cross-linking and apply them to the synthesis of hydrogels. Thiol-functionalized four-arm poly(ethylene glycol) and hyaluronic acid monomers were cross-linked with 1,2-dithiane-1-oxide to form disulfide cross-linked hydrogels within seconds. The synthesized hydrogel could be reduced with physiological concentrations of glutathione, which modulated hydrogel mechanical properties and degradation kinetics. Bovine serum albumin protein was successfully encapsulated in hydrogel, and diffusion-mediated release was demonstrated in vitro. Hep G2 cells grew in the presence of preformed hydrogel and during hydrogel synthesis, demonstrating acceptable cytotoxicity. We encapsulated cells within a hydrogel and demonstrated cell growth and recovery up to 10 days, with and without cell adhesion peptides. In summary, we report cyclic thiosulfinates as a novel class of cross-linkers for the facile synthesis of biodegradable hydrogels.
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Affiliation(s)
- Krishna C Aluri
- Department of Chemistry and Chemical Biology, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115, United States.,Barnett Institute of Chemical and Biological Analysis, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
| | - Md Amin Hossain
- Department of Chemistry and Chemical Biology, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115, United States.,Barnett Institute of Chemical and Biological Analysis, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
| | - Ninad Kanetkar
- Department of Chemical Engineering, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
| | - Brandon C Miller
- Department of Chemistry and Chemical Biology, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
| | - Matthew G Dowgiallo
- Department of Chemistry and Chemical Biology, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
| | - Durgalakshmi Sivasankar
- Department of Chemistry and Chemical Biology, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115, United States.,Barnett Institute of Chemical and Biological Analysis, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
| | - Matthew R Sullivan
- Department of Pharmaceutical Sciences, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
| | - Roman Manetsch
- Department of Chemistry and Chemical Biology, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115, United States.,Department of Pharmaceutical Sciences, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
| | - Tania Konry
- Department of Pharmaceutical Sciences, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
| | - Adam Ekenseair
- Department of Chemical Engineering, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
| | - Jeffrey N Agar
- Department of Chemistry and Chemical Biology, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115, United States.,Barnett Institute of Chemical and Biological Analysis, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115, United States.,Department of Pharmaceutical Sciences, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
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8
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Challenges and solutions for fabrication of three-dimensional cocultures of neural cell-loaded biomimetic constructs. Biointerphases 2021; 16:011202. [PMID: 33706526 DOI: 10.1116/6.0000700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Fabrication of three-dimensional (3D) constructs to model body tissues and organs can contribute to research into tissue development and models for studying disease, as well as supporting preclinical drug screening in vitro. Furthermore, 3D constructs can also be used for diagnosis and therapy of disease conditions via lab on a chip and microarrays for diagnosis and engineered products for tissue repair, replacement, and regeneration. While cell culture approaches for studying tissue development and disease in two dimensions are long-established, the translation of this knowledge into 3D environments remains a fertile field of research. In this Tutorial, we specifically focus on the application of biosynthetic hydrogels for neural cell encapsulation. The Tutorial briefly covers background on using biosynthetic hydrogels for cell encapsulation, as well as common fabrication techniques. The Methods section focuses on the hydrogel design and characterization, highlighting key elements and tips for more effective approaches. Coencapsulation of different cell types, and the challenges associated with different growth and maintenance requirements, is the main focus of this Tutorial. Much care is needed to blend different cell types, and this Tutorial provides tips and insights that have proven successful for 3D coculture in biosynthetic hydrogels.
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9
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Lee DH, Arisaka Y, Tonegawa A, Kang TW, Tamura A, Yui N. Cellular Orientation on Repeatedly Stretching Gelatin Hydrogels with Supramolecular Cross-Linkers. Polymers (Basel) 2019; 11:polym11122095. [PMID: 31847323 PMCID: PMC6960878 DOI: 10.3390/polym11122095] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Accepted: 12/12/2019] [Indexed: 12/20/2022] Open
Abstract
The cytocompatibility of biological and synthetic materials is an important issue for biomaterials. Gelatin hydrogels are used as biomaterials because of their biodegradability. We have previously reported that the mechanical properties of gelatin hydrogels are improved by cross-linking with polyrotaxanes, a supramolecular compound composed of many cyclic molecules threaded with a linear polymer. In this study, the ability of gelatin hydrogels cross-linked by polyrotaxanes (polyrotaxane–gelatin hydrogels) for cell cultivation was investigated. Because the amount of polyrotaxanes used for gelatin fabrication is very small, the chemical composition was barely altered. The structure and wettability of these hydrogels are also the same as those of conventional hydrogels. Fibroblasts adhered on polyrotaxane–gelatin hydrogels and conventional hydrogels without any reduction or apoptosis of adherent cells. From these results, the polyrotaxane–gelatin hydrogels have the potential to improve the mechanical properties of gelatin without affecting cytocompatibility. Interestingly, when cells were cultured on polyrotaxane–gelatin hydrogels after repeated stress deformation, the cells were spontaneously oriented to the stretching direction. This cellular response was not observed on conventional hydrogels. These results suggest that the use of a polyrotaxane cross-linking agent can not only improve the strength of hydrogels but can also contribute to controlling reorientation of the gelatin.
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10
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Liu Y, Dong R, Zhang C, Yang Y, Xu Y, Wang H, Zhang M, Zhu J, Wang Y, Sun Y, Zhang Z. Therapeutic effects of nerve leachate-treated adipose-derived mesenchymal stem cells on rat sciatic nerve injury. Exp Ther Med 2019; 19:223-231. [PMID: 31853293 PMCID: PMC6909684 DOI: 10.3892/etm.2019.8203] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Accepted: 09/26/2019] [Indexed: 02/06/2023] Open
Abstract
Peripheral nerve injury (PNI) is a common condition, often resulting from physical nerve injury and trauma. Successful repair of the peripheral nerve is dependent on the regenerative activity of Schwann cells (SCs). Application of SC-like adipose-derived mesenchymal stem cells (ADSCs) may be a suitable cell-based therapy for PNI. In the present study, nerve leachate derived from the rat sciatic nerve was used to induce the differentiation of ADSCs. These cells were placed in an acellular biological scaffold, which was then grafted to a rat sciatic nerve to bridge a 1-cm gap. Sprague-Dawley rats were divided into four groups: Scaffold only, untreated ADSCs + scaffold, nerve leachate-treated ADSCs + scaffold and autograft. Two-months post-transplant, the structure and function of the regenerated nerves and the recovery of the innervated muscles was analyzed. After transplant, there was a significant increase in the average area (15.86%; P<0.05), density (23.13%; P<0.05) and thickness (43.24%; P<0.05) of regenerated nerve fibers in the nerve leachate-treated ADSCs + scaffold group compared with the untreated ADSCs + scaffold group. The nerve conduction velocity in the nerve leachate-treated ADSCs + scaffold and autograft groups was superior to that in the other groups. In the nerve leachate-treated ADSCs + scaffold group, the cross-sectional area of the gastrocnemius increased by 39.28% (P<0.05) and the cross-sectional area of collagen fibers decreased by 29.87% (P<0.05) compared with the ADSCs + scaffold group. Moreover, the therapeutic effect of nerve leachate-treated ADSCs + scaffold on PNI was similar to that of an autograft. These results suggest that nerve leachate-treated ADSCs may promote the repair of PNI.
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Affiliation(s)
- Yumei Liu
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, Henan 471023, P.R. China
| | - Ruiqi Dong
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, Henan 471023, P.R. China
| | - Chunyan Zhang
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, Henan 471023, P.R. China
| | - Yuxiang Yang
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, Henan 471023, P.R. China
| | - Yaolu Xu
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, Henan 471023, P.R. China
| | - Haojie Wang
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, Henan 471023, P.R. China
| | - Mengyu Zhang
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, Henan 471023, P.R. China
| | - Jiamin Zhu
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, Henan 471023, P.R. China
| | - Yuqin Wang
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, Henan 471023, P.R. China.,Engineering Research Center for Mutton Sheep Breeding of Henan Province, Luoyang, Henan 471023, P.R. China
| | - Yanhong Sun
- Department of Physiology, Inner Mongolia Medical University, Hohhot, Inner Mongolia 010110, P.R. China
| | - Ziqiang Zhang
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, Henan 471023, P.R. China
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11
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Aregueta-Robles UA, Martens PJ, Poole-Warren LA, Green RA. Tissue engineered hydrogels supporting 3D neural networks. Acta Biomater 2019; 95:269-284. [PMID: 30500450 DOI: 10.1016/j.actbio.2018.11.044] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2018] [Revised: 11/08/2018] [Accepted: 11/26/2018] [Indexed: 01/07/2023]
Abstract
Promoting nerve regeneration requires engineering cellular carriers to physically and biochemically support neuronal growth into a long lasting functional tissue. This study systematically evaluated the capacity of a biosynthetic poly(vinyl alcohol) (PVA) hydrogel to support growth and differentiation of co-encapsulated neurons and glia. A significant challenge is to understand the role of the dynamic degradable hydrogel mechanical properties on expression of relevant cellular morphologies and function. It was hypothesised that a carrier with mechanical properties akin to neural tissue will provide glia with conditions to thrive, and that glia in turn will support neuronal survival and development. PVA co-polymerised with biological macromolecules sericin and gelatin (PVA-SG) and with tailored nerve tissue-like mechanical properties were used to encapsulate Schwann cells (SCs) alone and subsequently a co-culture of SCs and neural-like PC12s. SCs were encapsulated within two PVA-SG gel variants with initial compressive moduli of 16 kPa and 2 kPa, spanning a range of reported mechanical properties for neural tissues. Both hydrogels were shown to support cell viability and expression of extracellular matrix proteins, however, SCs grown within the PVA-SG with a higher initial modulus were observed to present with greater physiologically relevant morphologies and increased expression of extracellular matrix proteins. The higher modulus PVA-SG was subsequently shown to support development of neuronal networks when SCs were co-encapsulated with PC12s. The lower modulus hydrogel was unable to support effective development of neural networks. This study demonstrates the critical link between hydrogel properties and glial cell phenotype on development of functional neural tissues. STATEMENT OF SIGNIFICANCE: Hydrogels as platforms for tissue regeneration must provide encapsulated cellular progenitors with physical and biochemical cues for initial survival and to support ongoing tissue formation as the artificial network degrades. While most research focuses on tailoring scaffold properties to suit neurons, this work aims to support glia SCs as the key cellular component that physically and biochemically supports the neuronal network. The challenge is to modify hydrogel properties to support growth and development of multiple cell types into a neuronal network. Given SCs ability to respond to substrate mechanical properties, the significance of this work lies in understanding the relationship between dynamic hydrogel mechanical properties and glia SCs development as the element that enables formation of mature, differentiated neural networks.
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Affiliation(s)
| | - Penny J Martens
- Graduate School of Biomedical Engineering, University of New South Wales, Sydney, Australia
| | - Laura A Poole-Warren
- Graduate School of Biomedical Engineering, University of New South Wales, Sydney, Australia
| | - Rylie A Green
- Department of Bioengineering, Imperial College London, London, UK
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12
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Tytgat L, Van Damme L, Van Hoorick J, Declercq H, Thienpont H, Ottevaere H, Blondeel P, Dubruel P, Van Vlierberghe S. Additive manufacturing of photo-crosslinked gelatin scaffolds for adipose tissue engineering. Acta Biomater 2019; 94:340-350. [PMID: 31136829 DOI: 10.1016/j.actbio.2019.05.062] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 05/20/2019] [Accepted: 05/23/2019] [Indexed: 01/22/2023]
Abstract
There exists a clear clinical need for adipose tissue reconstruction strategies to repair soft tissue defects which outperform the currently available approaches. In this respect, additive manufacturing has shown to be a promising alternative for the development of larger constructs able to support adipose tissue engineering. In the present work, a thiol-ene photo-click crosslinkable gelatin hydrogel was developed which allowed extrusion-based additive manufacturing into porous scaffolds. To this end, norbornene-functionalized gelatin (Gel-NB) was combined with thiolated gelatin (Gel-SH). The application of a macromolecular gelatin-based thiolated crosslinker holds several advantages over conventional crosslinkers including cell-interactivity, less chance at phase separation between scaffold material and crosslinker and the formation of a more homogeneous network. Throughout the paper, these photo-click scaffolds were benchmarked to the conventional methacrylamide-modified gelatin (Gel-MA). The results indicated that stable scaffolds could be realized which were further characterized physico-chemically by performing swelling, mechanical and in vitro biodegradability assays. Furthermore, the seeded adipose tissue-derived stem cells (ASCs) remained viable (>90%) up to 14 days and were able to proliferate. In addition, the cells could be differentiated into the adipogenic lineage on the photo-click crosslinked scaffolds, thereby performing better than the cells supported by the frequently reported Gel-MA scaffolds. As a result, the developed photo-click crosslinked scaffolds can be considered a promising candidate towards adipose tissue engineering and a valuable alternative for the omnipresent Gel-MA. STATEMENT OF SIGNIFICANCE: The field of adipose tissue engineering has emerged as a promising strategy to repair soft tissue defects. Herein, Gel-NB/Gel-SH gelatin-based hydrogel scaffolds were produced using extrusion-based additive manufacturing. Using a cell-interactive, thiolated gelatin crosslinker, a homogeneous network was formed and the risk of phase separation between norbornene-modified gelatin and macromolecular crosslinkers was reduced. UV-induced crosslinking of these materials is based on step growth polymerization which requires less free radicals to enable polymerization. Our results demonstrated the potential of the developed scaffolds, due to their favourable physico-chemical characteristics as well as their adipogenic differentiation potential when benchmarked to Gel-MA scaffolds. Hence, the hydrogels could be of great interest towards future development of adipose tissue constructs and tissue engineering in general.
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Affiliation(s)
- Liesbeth Tytgat
- Brussels Photonics (B-PHOT) - Department of Applied Physics and Photonics, Vrije Universiteit Brussel and Flanders Make, Pleinlaan 2, 1050 Brussels, Belgium; Polymer Chemistry & Biomaterials Group - Centre of Macromolecular Chemistry (CMaC) - Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281, S4-Bis, 9000 Ghent, Belgium
| | - Lana Van Damme
- Polymer Chemistry & Biomaterials Group - Centre of Macromolecular Chemistry (CMaC) - Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281, S4-Bis, 9000 Ghent, Belgium; Department of Plastic & Reconstructive Surgery, Ghent University Hospital, Corneel Heymanslaan 10, 2K12, 9000 Ghent, Belgium
| | - Jasper Van Hoorick
- Brussels Photonics (B-PHOT) - Department of Applied Physics and Photonics, Vrije Universiteit Brussel and Flanders Make, Pleinlaan 2, 1050 Brussels, Belgium; Polymer Chemistry & Biomaterials Group - Centre of Macromolecular Chemistry (CMaC) - Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281, S4-Bis, 9000 Ghent, Belgium
| | - Heidi Declercq
- Tissue Engineering and Biomaterials Group - Department of Human Structure and Repair, Ghent University, Corneel Heymanslaan 10, 6B3, 9000 Ghent, Belgium
| | - Hugo Thienpont
- Brussels Photonics (B-PHOT) - Department of Applied Physics and Photonics, Vrije Universiteit Brussel and Flanders Make, Pleinlaan 2, 1050 Brussels, Belgium
| | - Heidi Ottevaere
- Brussels Photonics (B-PHOT) - Department of Applied Physics and Photonics, Vrije Universiteit Brussel and Flanders Make, Pleinlaan 2, 1050 Brussels, Belgium
| | - Phillip Blondeel
- Department of Plastic & Reconstructive Surgery, Ghent University Hospital, Corneel Heymanslaan 10, 2K12, 9000 Ghent, Belgium
| | - Peter Dubruel
- Polymer Chemistry & Biomaterials Group - Centre of Macromolecular Chemistry (CMaC) - Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281, S4-Bis, 9000 Ghent, Belgium
| | - Sandra Van Vlierberghe
- Brussels Photonics (B-PHOT) - Department of Applied Physics and Photonics, Vrije Universiteit Brussel and Flanders Make, Pleinlaan 2, 1050 Brussels, Belgium; Polymer Chemistry & Biomaterials Group - Centre of Macromolecular Chemistry (CMaC) - Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281, S4-Bis, 9000 Ghent, Belgium
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13
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Teleanu RI, Gherasim O, Gherasim TG, Grumezescu V, Grumezescu AM, Teleanu DM. Nanomaterial-Based Approaches for Neural Regeneration. Pharmaceutics 2019; 11:E266. [PMID: 31181719 PMCID: PMC6630326 DOI: 10.3390/pharmaceutics11060266] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 06/03/2019] [Accepted: 06/04/2019] [Indexed: 12/13/2022] Open
Abstract
Mechanical, thermal, chemical, or ischemic injury of the central or peripheral nervous system results in neuron loss, neurite damage, and/or neuronal dysfunction, almost always accompanied by sensorimotor impairment which alters the patient's life quality. The regenerative strategies for the injured nervous system are currently limited and mainly allow partial functional recovery, so it is necessary to develop new and effective approaches for nervous tissue regenerative therapy. Nanomaterials based on inorganic or organic and composite or hybrid compounds with tunable physicochemical properties and functionality proved beneficial for the transport and delivery/release of various neuroregenerative-relevant biomolecules or cells. Within the following paragraphs, we will emphasize that nanomaterial-based strategies (including nanosized and nanostructured biomaterials) represent a promising alternative towards repairing and regenerating the injured nervous system.
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Affiliation(s)
- Raluca Ioana Teleanu
- "Victor Gomoiu" Clinical Children's Hospital, "Carol Davila" University of Medicine and Pharmacy, 050474 Bucharest, Romania.
| | - Oana Gherasim
- Department of Science and Engineering of Oxide Materials and Nanomaterials, Faculty of Applied Chemistry and Materials Science, Politehnica University of Bucharest, 011061 Bucharest, Romania.
- Lasers Department, National Institute for Lasers, Plasma and Radiation Physics, 077125 Magurele, Romania.
| | - Tudor George Gherasim
- National Institute of Neurology and Neurovascular Diseases, 077160 Bucharest, Romania.
| | - Valentina Grumezescu
- Lasers Department, National Institute for Lasers, Plasma and Radiation Physics, 077125 Magurele, Romania.
| | - Alexandru Mihai Grumezescu
- Department of Science and Engineering of Oxide Materials and Nanomaterials, Faculty of Applied Chemistry and Materials Science, Politehnica University of Bucharest, 011061 Bucharest, Romania.
| | - Daniel Mihai Teleanu
- Emergency University Hospital, "Carol Davila" University of Medicine and Pharmacy, 050474 Bucharest, Romania.
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14
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Cavanaugh M, Silantyeva E, Pylypiv Koh G, Malekzadeh E, Lanzinger WD, Willits RK, Becker ML. RGD-Modified Nanofibers Enhance Outcomes in Rats after Sciatic Nerve Injury. J Funct Biomater 2019; 10:jfb10020024. [PMID: 31146396 PMCID: PMC6637389 DOI: 10.3390/jfb10020024] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 05/13/2019] [Accepted: 05/22/2019] [Indexed: 01/23/2023] Open
Abstract
Nerve injuries requiring surgery are a significant problem without good clinical alternatives to the autograft. Tissue engineering strategies are critically needed to provide an alternative. In this study, we utilized aligned nanofibers that were click-modified with the bioactive peptide RGD for rat sciatic nerve repair. Empty conduits or conduits filled with either non-functionalized aligned nanofibers or RGD-functionalized aligned nanofibers were used to repair a 13 mm gap in the rat sciatic nerve of animals for six weeks. The aligned nanofibers encouraged cell infiltration and nerve repair as shown by histological analysis. RGD-functionalized nanofibers reduced muscle atrophy. During the six weeks of recovery, the animals were subjected to motor and sensory tests. Sensory recovery was improved in the RGD-functionalized nanofiber group by week 4, while other groups needed six weeks to show improvement after injury. Thus, the use of functionalized nanofibers provides cues that aid in in vivo nerve repair and should be considered as a future repair strategy.
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Affiliation(s)
- McKay Cavanaugh
- Department of Biomedical Engineering, The University of Akron, Akron, OH 44325-0302, USA.
| | - Elena Silantyeva
- Department of Polymer Science, The University of Akron, Akron, OH 44325, USA.
| | - Galina Pylypiv Koh
- Department of Biomedical Engineering, The University of Akron, Akron, OH 44325-0302, USA.
| | - Elham Malekzadeh
- Department of Biomedical Engineering, The University of Akron, Akron, OH 44325-0302, USA.
| | | | - Rebecca Kuntz Willits
- Department of Biomedical Engineering, The University of Akron, Akron, OH 44325-0302, USA.
| | - Matthew L Becker
- Department of Polymer Science, The University of Akron, Akron, OH 44325, USA.
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15
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Karg M, Pich A, Hellweg T, Hoare T, Lyon LA, Crassous JJ, Suzuki D, Gumerov RA, Schneider S, Potemkin II, Richtering W. Nanogels and Microgels: From Model Colloids to Applications, Recent Developments, and Future Trends. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:6231-6255. [PMID: 30998365 DOI: 10.1021/acs.langmuir.8b04304] [Citation(s) in RCA: 310] [Impact Index Per Article: 62.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Nanogels and microgels are soft, deformable, and penetrable objects with an internal gel-like structure that is swollen by the dispersing solvent. Their softness and the potential to respond to external stimuli like temperature, pressure, pH, ionic strength, and different analytes make them interesting as soft model systems in fundamental research as well as for a broad range of applications, in particular in the field of biological applications. Recent tremendous developments in their synthesis open access to systems with complex architectures and compositions allowing for tailoring microgels with specific properties. At the same time state-of-the-art theoretical and simulation approaches offer deeper understanding of the behavior and structure of nano- and microgels under external influences and confinement at interfaces or at high volume fractions. Developments in the experimental analysis of nano- and microgels have become particularly important for structural investigations covering a broad range of length scales relevant to the internal structure, the overall size and shape, and interparticle interactions in concentrated samples. Here we provide an overview of the state-of-the-art, recent developments as well as emerging trends in the field of nano- and microgels. The following aspects build the focus of our discussion: tailoring (multi)functionality through synthesis; the role in biological and biomedical applications; the structure and properties as a model system, e.g., for densely packed arrangements in bulk and at interfaces; as well as the theory and computer simulation.
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Affiliation(s)
- Matthias Karg
- Physical Chemistry I , Heinrich-Heine-University Duesseldorf , 40204 Duesseldorf , Germany
| | - Andrij Pich
- DWI-Leibnitz-Institute for Interactive Materials e.V. , 52056 Aachen , Germany
- Functional and Interactive Polymers, Institute for Technical and Macromolecular Chemistry , RWTH Aachen University , 52056 Aachen , Germany
| | - Thomas Hellweg
- Physical and Biophysical Chemistry , Bielefeld University , 33615 Bielefeld , Germany
| | - Todd Hoare
- Department of Chemical Engineering , McMaster University , Hamilton , Ontario L8S 4L8 , Canada
| | - L Andrew Lyon
- Schmid College of Science and Technology , Chapman University , Orange , California 92866 , United States
| | - J J Crassous
- Institute of Physical Chemistry , RWTH Aachen University , 52056 Aachen , Germany
| | | | - Rustam A Gumerov
- DWI-Leibnitz-Institute for Interactive Materials e.V. , 52056 Aachen , Germany
- Physics Department , Lomonosov Moscow State University , Moscow 119991 , Russian Federation
| | - Stefanie Schneider
- Institute of Physical Chemistry , RWTH Aachen University , 52056 Aachen , Germany
| | - Igor I Potemkin
- DWI-Leibnitz-Institute for Interactive Materials e.V. , 52056 Aachen , Germany
- Physics Department , Lomonosov Moscow State University , Moscow 119991 , Russian Federation
- National Research South Ural State University , Chelyabinsk 454080 , Russian Federation
| | - Walter Richtering
- Institute of Physical Chemistry , RWTH Aachen University , 52056 Aachen , Germany
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16
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George J, Hsu CC, Nguyen LTB, Ye H, Cui Z. Neural tissue engineering with structured hydrogels in CNS models and therapies. Biotechnol Adv 2019; 42:107370. [PMID: 30902729 DOI: 10.1016/j.biotechadv.2019.03.009] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Revised: 02/25/2019] [Accepted: 03/11/2019] [Indexed: 01/27/2023]
Abstract
The development of techniques to create and use multiphase microstructured hydrogels (granular hydrogels or microgels) has enabled the generation of cultures with more biologically relevant architecture and use of structured hydrogels is especially pertinent to the development of new types of central nervous system (CNS) culture models and therapies. We review material choice and the customisation of hydrogel structure, as well as the use of hydrogels in developmental models. Combining the use of structured hydrogel techniques with developmentally relevant tissue culture approaches will enable the generation of more relevant models and treatments to repair damaged CNS tissue architecture.
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Affiliation(s)
- Julian George
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, United Kingdom
| | - Chia-Chen Hsu
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, United Kingdom
| | - Linh Thuy Ba Nguyen
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, United Kingdom
| | - Hua Ye
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, United Kingdom.
| | - Zhanfeng Cui
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, United Kingdom.
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17
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Livingston MK, Morgan MM, Daly WT, Murphy WL, Johnson BP, Beebe DJ, Virumbrales-Muñoz M. Evaluation of PEG-based hydrogel influence on estrogen receptor driven responses in MCF7 breast cancer cells. ACS Biomater Sci Eng 2019; 5:6089-6098. [PMID: 31942444 PMCID: PMC6961958 DOI: 10.1021/acsbiomaterials.9b00480] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Extracellular matrix (ECM) mimicking hydrogel scaffolds have greatly improved the physiological relevance of in vitro assays, but introduce another dimension that creates variability in cell related readouts when compared to traditional 2D cells-on-plastic assays. We have developed a synthetic poly(ethylene glycol) (PEG) based ECM mimicking hydrogel and tested it against two gold standard animal-based naturally derived hydrogel scaffolds in MCF7 cell response. We have used the percent coefficient of variation (CV) as a metric to evaluate the reproducibility of said responses. Results indicated that PEG hydrogels performed similarly to naturally derived gold standards, and variance was similar in basic characterization assays, such as viability and cell adherence. PEG based hydrogels had lower CV values in estrogen receptor driven responses to several doses of estrogen in both estrogen receptor transactivation and estrogen induced proliferation.
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Affiliation(s)
- Megan K. Livingston
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI 53706
- School of Medicine and Public Health, University of Wisconsin-Madison, 750 Highland Ave, Madison, WI 53726
| | - Molly M. Morgan
- School of Medicine and Public Health, University of Wisconsin-Madison, 750 Highland Ave, Madison, WI 53726
| | - William T. Daly
- Department of Orthopedics and Rehabilitation, University of Wisconsin-Madison, 1111 Highland Ave, Madison, WI 55705
| | - William L. Murphy
- Department of Orthopedics and Rehabilitation, University of Wisconsin-Madison, 1111 Highland Ave, Madison, WI 55705
- Department of Biomedical Engineering, University of Wisconsin-Madison, 1550 Engineering Dr, Madison, WI 53706
- Department of Materials Science and Engineering, University of Wisconsin-Madison, 1509 University Ave, Madison, WI 53706
| | - Brian P. Johnson
- School of Medicine and Public Health, University of Wisconsin-Madison, 750 Highland Ave, Madison, WI 53726
| | - David J. Beebe
- School of Medicine and Public Health, University of Wisconsin-Madison, 750 Highland Ave, Madison, WI 53726
| | - Maria Virumbrales-Muñoz
- School of Medicine and Public Health, University of Wisconsin-Madison, 750 Highland Ave, Madison, WI 53726
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18
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Do AV, Worthington K, Tucker B, Salem AK. Controlled drug delivery from 3D printed two-photon polymerized poly(ethylene glycol) dimethacrylate devices. Int J Pharm 2018; 552:217-224. [PMID: 30268853 PMCID: PMC6204107 DOI: 10.1016/j.ijpharm.2018.09.065] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Revised: 09/24/2018] [Accepted: 09/26/2018] [Indexed: 02/07/2023]
Abstract
Controlled drug delivery systems have been utilized to enhance the therapeutic effects of many drugs by delivering drugs in a time-dependent and sustained manner. Here, with the aid of 3D printing technology, drug delivery devices were fabricated and tested using a model drug (fluorophore: rhodamine B). Poly(ethylene glycol) dimethacrylate (PEGDMA) devices were fabricated using a two-photon polymerization (TPP) system and rhodamine B was homogenously entrapped inside the polymer matrix during photopolymerization. These devices were printed with varying porosity and morphology using varying printing parameters such as slicing and hatching distance. The effects of these variables on drug release kinetics were determined by evaluating device fluorescence over the course of one week. These PEGDMA-based structures were then investigated for toxicity and biocompatibility in vitro, where MTS assays were performed using a range of cell types including induced pluripotent stem cells (iPSCs). Overall, tuning the hatching distance, slicing distance, and pore size of the fabricated devices modulated the rhodamine B release profile, in each case presumably due to resulting changes in the motility of the small molecule and its access to structure edges. In general, increased spacing provided higher drug release while smaller spacing resulted in some occlusion, preventing media infiltration and thus resulting in reduced fluorophore release. The devices had no cytotoxic effects on human embryonic kidney cells (HEK293), bone marrow stromal stem cells (BMSCs) or iPSCs. Thus, we have demonstrated the utility of two-photon polymerization to create biocompatible, complex miniature devices with fine details and tunable release of a model drug.
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Affiliation(s)
- Anh-Vu Do
- Division of Pharmaceutics and Translational Therapeutics, College of Pharmacy, University of Iowa,Department of Chemical and Biochemical Engineering, College of Engineering, The University of Iowa
| | - Kristan Worthington
- Institute for Vision Research, Department of Ophthalmology and Visual Sciences, College of Medicine, The University of Iowa,Department of Biomedical Engineering, College of Engineering, The University of Iowa
| | - Budd Tucker
- Institute for Vision Research, Department of Ophthalmology and Visual Sciences, College of Medicine, The University of Iowa
| | - Aliasger K. Salem
- Division of Pharmaceutics and Translational Therapeutics, College of Pharmacy, University of Iowa,Department of Chemical and Biochemical Engineering, College of Engineering, The University of Iowa,Department of Biomedical Engineering, College of Engineering, The University of Iowa,
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19
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Hou S, Lake R, Park S, Edwards S, Jones C, Jeong KJ. Injectable Macroporous Hydrogel Formed by Enzymatic Cross-Linking of Gelatin Microgels. ACS APPLIED BIO MATERIALS 2018; 1:1430-1439. [PMID: 31701093 DOI: 10.1021/acsabm.8b00380] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Injectable hydrogels can be useful tools for facilitating wound healing since they conform to the irregular shapes of wounds, serving as a temporary matrix during the healing process. However, the lack of inherent pore structures of most injectable hydrogels prohibits desired interactions with the cells of the surrounding tissues limiting their clinical efficacy. Here, we introduce a simple, cost-effective and highly biofunctional injectable macroporous hydrogel made of gelatin microgels crosslinked by microbial transglutaminase (mTG). Pores are created by the interstitial space among the microgels. A water-in-oil emulsion technique was used to create gelatin microgels of an average size of 250μm in diameter. When crosslinked with mTG, the microgels adhered to each other to form a bulk hydrogel with inherent pores large enough for cell migration. The viscoelastic properties of the porous hydrogel were similar to those of nonporous gelatin hydrogel made by adding mTG to a homogeneous gelatin solution. The porous hydrogel supported higher cellular proliferation of human dermal fibroblasts (hDFs) than the nonporous hydrogel over two weeks, and allowed the migration of hDFs into the pores. Conversely, the hDFs were unable to permeate the surface of the nonporous hydrogel. To demonstrate its potential use in wound healing, the gelatin microgels were injected with mTG into a cut out section of an excised porcine cornea. Due to the action of mTG, the porous hydrogel stably adhered to the cornea tissue for two weeks. Confocal images showed that a large number of cells from the cornea tissue migrated into the interstitial space of the porous hydrogel. The porous hydrogel was also used for the controlled release of platelet-derived growth factor (PDGF), increasing the proliferation of hDFs compared to the nonporous hydrogel. This gelatin microgel-based porous hydrogel will be a useful tool for wound healing and tissue engineering.
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Affiliation(s)
- Shujie Hou
- Department of Chemical Engineering, University of New Hampshire, Durham, NH 03824
| | - Rachel Lake
- Department of Chemical Engineering, University of New Hampshire, Durham, NH 03824
| | - Shiwha Park
- Department of Chemical Engineering, University of New Hampshire, Durham, NH 03824
| | - Seth Edwards
- Department of Chemical Engineering, University of New Hampshire, Durham, NH 03824
| | - Chante Jones
- Department of Chemical Engineering, University of New Hampshire, Durham, NH 03824
| | - Kyung Jae Jeong
- Department of Chemical Engineering, University of New Hampshire, Durham, NH 03824
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20
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Xin S, Wyman OM, Alge DL. Assembly of PEG Microgels into Porous Cell-Instructive 3D Scaffolds via Thiol-Ene Click Chemistry. Adv Healthc Mater 2018; 7:e1800160. [PMID: 29663702 PMCID: PMC6262827 DOI: 10.1002/adhm.201800160] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Indexed: 11/07/2022]
Abstract
The assembly of microgel building blocks into 3D scaffolds is an emerging strategy for tissue engineering. A key advantage is that the inherent microporosity of these scaffolds provides cells with a more permissive environment than conventional nanoporous hydrogels. Here, norbornene-bearing poly(ethylene glycol) (PEG) based microgels are assembled into 3D cell-instructive scaffolds using a PEG-dithiol linker and thiol-ene click photopolymerization. The bulk modulus of these materials depends primarily on the crosslink density of the microgel building blocks. However, the linker and initiator concentrations used during assembly have significant effects on cell spreading and proliferation when human mesenchymal stem cells (hMSCs) are incorporated in the scaffolds. The cell response is also affected by the properties of the modular microgel building blocks, as hMSCs growing in scaffolds assembled from stiff but not soft microgels activate Yes-associated protein signaling. These results indicate that PEG microgel scaffolds assembled via thiol-ene click chemistry can be engineered to provide a cell-instructive 3D milieu, making them a promising 3D platform for tissue engineering.
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Affiliation(s)
- Shangjing Xin
- Department of Biomedical Engineering, Texas A&M University, College Station, TX, 77843, USA
| | - Omar M Wyman
- Department of Biomedical Engineering, Texas A&M University, College Station, TX, 77843, USA
| | - Daniel L Alge
- Department of Biomedical Engineering, Texas A&M University, College Station, TX, 77843, USA
- Department of Materials Science and Engineering, Texas A&M University, College Station, TX, 77843, USA
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21
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Li L, Lu C, Wang L, Chen M, White J, Hao X, McLean KM, Chen H, Hughes TC. Gelatin-Based Photocurable Hydrogels for Corneal Wound Repair. ACS APPLIED MATERIALS & INTERFACES 2018; 10:13283-13292. [PMID: 29620862 DOI: 10.1021/acsami.7b17054] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
In this study, an injectable, photocurable gelatin system, consisting of acrylated gelatin and thiolated gelatin, with tunable mechanical, biodegradation, and biological properties was used as a potential cell-supportive scaffold for the repair of focal corneal wounds. The mechanical property of hydrogels can be readily modified (postcure shear modulus of between 0.3 and 22 kPa) by varying the ratio of acrylate to thiol groups, photointensity, and solid content, and the biodegradation times also varied with the change of solid content. More importantly, the generated hydrogels exhibited excellent cell viability in both cell seeding and cell encapsulation experiments. Furthermore, the hydrogels were found to be biocompatible with rabbit cornea and aided the regeneration of a new tissue under a focal corneal wound (exhibiting epithelial wound coverage in <3d), and ultraviolet irradiation did not have any obvious harmful effect on the cornea and posterior eye segment tissues. Along with their injectability and tunable mechanical properties, the photocurable thiol-acrylate hydrogels showed promise as corneal substitutes or substrates to construct a new corneal tissue.
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Affiliation(s)
- Lingli Li
- School of Ophthalmology & Optometry, Eye Hospital , Wenzhou Medical University , Wenzhou , Zhejiang Province 325000 , PRC
- Wenzhou Institute of Biomaterials and Engineering , Wenzhou , Zhejiang Province 325001 , PRC
| | - Conglie Lu
- School of Ophthalmology & Optometry, Eye Hospital , Wenzhou Medical University , Wenzhou , Zhejiang Province 325000 , PRC
| | - Lei Wang
- Wenzhou Institute of Biomaterials and Engineering , Wenzhou , Zhejiang Province 325001 , PRC
| | - Mei Chen
- School of Ophthalmology & Optometry, Eye Hospital , Wenzhou Medical University , Wenzhou , Zhejiang Province 325000 , PRC
| | - Jacinta White
- CSIRO Manufacturing , Clayton , Victoria 3169 , Australia
| | - Xiaojuan Hao
- CSIRO Manufacturing , Clayton , Victoria 3169 , Australia
| | - Keith M McLean
- CSIRO Manufacturing , Clayton , Victoria 3169 , Australia
| | - Hao Chen
- School of Ophthalmology & Optometry, Eye Hospital , Wenzhou Medical University , Wenzhou , Zhejiang Province 325000 , PRC
- Wenzhou Institute of Biomaterials and Engineering , Wenzhou , Zhejiang Province 325001 , PRC
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22
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Wrobel MR, Sundararaghavan HG. Biomaterial Cues to Direct a Pro-regenerative Phenotype in Macrophages and Schwann Cells. Neuroscience 2018; 376:172-187. [DOI: 10.1016/j.neuroscience.2018.02.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Revised: 01/23/2018] [Accepted: 02/09/2018] [Indexed: 12/11/2022]
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23
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Liang C, Luo Y, Yang G, Xia D, Liu L, Zhang X, Wang H. Graphene Oxide Hybridized nHAC/PLGA Scaffolds Facilitate the Proliferation of MC3T3-E1 Cells. NANOSCALE RESEARCH LETTERS 2018; 13:15. [PMID: 29327198 PMCID: PMC5764901 DOI: 10.1186/s11671-018-2432-6] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Accepted: 01/02/2018] [Indexed: 06/07/2023]
Abstract
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.
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Affiliation(s)
- Chunyong Liang
- Research Institute for Energy Equipment Materials, Tianjin Key Laboratory of Materials Laminating Fabrication and Interface Control Technology, College of Materials Science and Engineering, Hebei University of Technology, Tianjin, 300130 China
| | - Yongchao Luo
- Research Institute for Energy Equipment Materials, Tianjin Key Laboratory of Materials Laminating Fabrication and Interface Control Technology, College of Materials Science and Engineering, Hebei University of Technology, Tianjin, 300130 China
| | - Guodong Yang
- Institute for Advanced Materials, Jiangsu University, Zhenjiang, People’s Republic of China
| | - Dan Xia
- Research Institute for Energy Equipment Materials, Tianjin Key Laboratory of Materials Laminating Fabrication and Interface Control Technology, College of Materials Science and Engineering, Hebei University of Technology, Tianjin, 300130 China
| | - Lei Liu
- Institute for Advanced Materials, Jiangsu University, Zhenjiang, People’s Republic of China
| | - Xiaomin Zhang
- Research Institute for Energy Equipment Materials, Tianjin Key Laboratory of Materials Laminating Fabrication and Interface Control Technology, College of Materials Science and Engineering, Hebei University of Technology, Tianjin, 300130 China
| | - Hongshui Wang
- Research Institute for Energy Equipment Materials, Tianjin Key Laboratory of Materials Laminating Fabrication and Interface Control Technology, College of Materials Science and Engineering, Hebei University of Technology, Tianjin, 300130 China
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Aregueta-Robles UA, Martens PJ, Poole-Warren LA, Green RA. Tailoring 3D hydrogel systems for neuronal encapsulation in living electrodes. ACTA ACUST UNITED AC 2017. [DOI: 10.1002/polb.24558] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
| | - Penny J. Martens
- Graduate School of Biomedical Engineering; University of New South Wales; Sydney 2052 Australia
| | - Laura A. Poole-Warren
- Graduate School of Biomedical Engineering; University of New South Wales; Sydney 2052 Australia
| | - Rylie A. Green
- Graduate School of Biomedical Engineering; University of New South Wales; Sydney 2052 Australia
- Department of Bioengineering; Imperial College London; London SW7 2AZ United Kingdom
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25
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Barriga-Rivera A, Bareket L, Goding J, Aregueta-Robles UA, Suaning GJ. Visual Prosthesis: Interfacing Stimulating Electrodes with Retinal Neurons to Restore Vision. Front Neurosci 2017; 11:620. [PMID: 29184478 PMCID: PMC5694472 DOI: 10.3389/fnins.2017.00620] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Accepted: 10/23/2017] [Indexed: 01/06/2023] Open
Abstract
The bypassing of degenerated photoreceptors using retinal neurostimulators is helping the blind to recover functional vision. Researchers are investigating new ways to improve visual percepts elicited by these means as the vision produced by these early devices remain rudimentary. However, several factors are hampering the progression of bionic technologies: the charge injection limits of metallic electrodes, the mechanical mismatch between excitable tissue and the stimulating elements, neural and electric crosstalk, the physical size of the implanted devices, and the inability to selectively activate different types of retinal neurons. Electrochemical and mechanical limitations are being addressed by the application of electromaterials such as conducting polymers, carbon nanotubes and nanocrystalline diamonds, among other biomaterials, to electrical neuromodulation. In addition, the use of synthetic hydrogels and cell-laden biomaterials is promising better interfaces, as it opens a door to establishing synaptic connections between the electrode material and the excitable cells. Finally, new electrostimulation approaches relying on the use of high-frequency stimulation and field overlapping techniques are being developed to better replicate the neural code of the retina. All these elements combined will bring bionic vision beyond its present state and into the realm of a viable, mainstream therapy for vision loss.
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Affiliation(s)
- Alejandro Barriga-Rivera
- Graduate School of Biomedical Engineering, University of New South Wales, Sydney, NSW, Australia
- Faculty of Engineering and Information Technologies, University of Sydney, Sydney, NSW, Australia
- Division of Neuroscience, University Pablo de Olavide, Sevilla, Spain
| | - Lilach Bareket
- Graduate School of Biomedical Engineering, University of New South Wales, Sydney, NSW, Australia
- Faculty of Engineering and Information Technologies, University of Sydney, Sydney, NSW, Australia
| | - Josef Goding
- Department of Bioengineering, Imperial College London, London, United Kingdom
| | | | - Gregg J. Suaning
- Faculty of Engineering and Information Technologies, University of Sydney, Sydney, NSW, Australia
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26
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Russell LN, Lampe KJ. Oligodendrocyte Precursor Cell Viability, Proliferation, and Morphology is Dependent on Mesh Size and Storage Modulus in 3D Poly(ethylene glycol)-Based Hydrogels. ACS Biomater Sci Eng 2017; 3:3459-3468. [PMID: 33445383 DOI: 10.1021/acsbiomaterials.7b00374] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Oligodendrocytes in the central nervous system (CNS) are responsible for generating myelin, an electrically insulating layer around neuronal axons. When myelin is damaged, neurons are incapable of sustaining normal communications, which can manifest in patients as pain and loss of mobility and vision. A plethora of research has used biomaterials to promote neuronal regeneration, but despite the wide implications of a disrupted myelin sheath, very little is known about how biomaterial environments impact proliferation of oligodendrocyte precursor cells (OPCs) or their differentiation into myelinating oligodendrocytes. This work investigates how the storage modulus and mesh size of a polyethylene glycol (PEG)-based hydrogel, varied via two different mechanisms, directly affect the proliferation of two OPC lines encapsulated and cultured in 3D. Viability and proliferation of both OPC lines was dependent on hydrogel swelling and stiffness, where the concentration of ATP increased more in the more compliant gels. OPCs multiplied in the 3D hydrogels, creating significantly larger spheroids in the less cross-linked conditions. Stiffer, more highly cross-linked materials lead to greater expression of PDGFRα, an OPC receptor, indicating that fewer cells were committed to the oligodendrocyte lineage or had dedifferentiated in compliant materials. Laminin incorporation in the 3D matrix was found to have little effect on viability or proliferation. These findings provide valuable information on how mesh size and stiffness affect OPCs where more compliant materials favor proliferation of OPCs with less commitment to a mature oligodendrocyte lineage. Such information will be useful in the development of translational biomaterials to stimulate oligodendrocyte maturation for neural regeneration.
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Affiliation(s)
- Lauren N Russell
- Department of Chemical Engineering, University of Virginia, 102 Engineers' Way, Charlottesville, Virginia 22904, United States
| | - Kyle J Lampe
- Department of Chemical Engineering, University of Virginia, 102 Engineers' Way, Charlottesville, Virginia 22904, United States
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27
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Lu B, Tarn MD, Pamme N, Georgiou TK. Fabrication of tailorable pH responsive cationic amphiphilic microgels on a microfluidic device for drug release. ACTA ACUST UNITED AC 2017. [DOI: 10.1002/pola.28860] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Bingyuan Lu
- School of Mathematics and Physical Sciences; University of Hull; HU6 7RX United Kingdom
| | - Mark D. Tarn
- School of Mathematics and Physical Sciences; University of Hull; HU6 7RX United Kingdom
| | - Nicole Pamme
- School of Mathematics and Physical Sciences; University of Hull; HU6 7RX United Kingdom
| | - Theoni K. Georgiou
- Department of Materials; Imperial College London, Royal School of Mines, Exhibition Road; London SW7 2AZ United Kingdom
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28
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Li L, Stiadle JM, Lau HK, Zerdoum AB, Jia X, Thibeault SL, Kiick KL. Tissue engineering-based therapeutic strategies for vocal fold repair and regeneration. Biomaterials 2016; 108:91-110. [PMID: 27619243 PMCID: PMC5035639 DOI: 10.1016/j.biomaterials.2016.08.054] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Revised: 08/29/2016] [Accepted: 08/31/2016] [Indexed: 01/01/2023]
Abstract
Vocal folds are soft laryngeal connective tissues with distinct layered structures and complex multicomponent matrix compositions that endow phonatory and respiratory functions. This delicate tissue is easily damaged by various environmental factors and pathological conditions, altering vocal biomechanics and causing debilitating vocal disorders that detrimentally affect the daily lives of suffering individuals. Modern techniques and advanced knowledge of regenerative medicine have led to a deeper understanding of the microstructure, microphysiology, and micropathophysiology of vocal fold tissues. State-of-the-art materials ranging from extracecullar-matrix (ECM)-derived biomaterials to synthetic polymer scaffolds have been proposed for the prevention and treatment of voice disorders including vocal fold scarring and fibrosis. This review intends to provide a thorough overview of current achievements in the field of vocal fold tissue engineering, including the fabrication of injectable biomaterials to mimic in vitro cell microenvironments, novel designs of bioreactors that capture in vivo tissue biomechanics, and establishment of various animal models to characterize the in vivo biocompatibility of these materials. The combination of polymeric scaffolds, cell transplantation, biomechanical stimulation, and delivery of antifibrotic growth factors will lead to successful restoration of functional vocal folds and improved vocal recovery in animal models, facilitating the application of these materials and related methodologies in clinical practice.
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Affiliation(s)
- Linqing Li
- Department of Materials Science and Engineering, University of Delaware, Newark, DE 19716, USA
| | - Jeanna M Stiadle
- Division of Otolaryngology-Head and Neck Surgery, Department of Surgery, University of Wisconsin-Madison, Madison, WI 53792, USA; Department of Communication Sciences and Disorders, University of Wisconsin-Madison, Madison, WI 53792, USA
| | - Hang K Lau
- Department of Materials Science and Engineering, University of Delaware, Newark, DE 19716, USA
| | - Aidan B Zerdoum
- Department of Biomedical Engineering, University of Delaware, Newark, DE 19716, USA
| | - Xinqiao Jia
- Department of Materials Science and Engineering, University of Delaware, Newark, DE 19716, USA; Department of Biomedical Engineering, University of Delaware, Newark, DE 19716, USA; Delaware Biotechnology Institute, 15 Innovation Way, Newark, DE 19711, USA
| | - Susan L Thibeault
- Division of Otolaryngology-Head and Neck Surgery, Department of Surgery, University of Wisconsin-Madison, Madison, WI 53792, USA; Department of Communication Sciences and Disorders, University of Wisconsin-Madison, Madison, WI 53792, USA.
| | - Kristi L Kiick
- Department of Materials Science and Engineering, University of Delaware, Newark, DE 19716, USA; Department of Biomedical Engineering, University of Delaware, Newark, DE 19716, USA; Delaware Biotechnology Institute, 15 Innovation Way, Newark, DE 19711, USA.
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