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Kunwar P, Aryal U, Poudel A, Fougnier D, Geffert ZJ, Xie R, Li Z, Soman P. Droplet bioprinting of acellular and cell-laden structures at high-resolutions. Biofabrication 2024; 16:035019. [PMID: 38749419 DOI: 10.1088/1758-5090/ad4c09] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Accepted: 05/15/2024] [Indexed: 05/24/2024]
Abstract
Advances in digital light projection(DLP) based (bio) printers have made printing of intricate structures at high resolution possible using a wide range of photosensitive bioinks. A typical setup of a DLP bioprinter includes a vat or reservoir filled with liquid bioink, which presents challenges in terms of cost associated with bioink synthesis, high waste, and gravity-induced cell settling, contaminations, or variation in bioink viscosity during the printing process. Here, we report a vat-free, low-volume, waste-free droplet bioprinting method capable of rapidly printing 3D soft structures at high resolution using model bioinks and model cells. A multiphase many-body dissipative particle dynamics model was developed to simulate the dynamic process of droplet-based DLP printing and elucidate the roles of surface wettability and bioink viscosity. Process variables such as light intensity, photo-initiator concentration, and bioink formulations were optimized to print 3D soft structures (∼0.4-3 kPa) with a typical layer thickness of 50µm, an XY resolution of 38 ± 1.5μm and Z resolution of 237 ± 5.4µm. To demonstrate its versatility, droplet bioprinting was used to print a range of acellular 3D structures such as a lattice cube, a Mayan pyramid, a heart-shaped structure, and a microfluidic chip with endothelialized channels. Droplet bioprinting, performed using model C3H/10T1/2 cells, exhibited high viability (90%) and cell spreading. Additionally, microfluidic devices with internal channel networks lined with endothelial cells showed robust monolayer formation while osteoblast-laden constructs showed mineral deposition upon osteogenic induction. Overall, droplet bioprinting could be a low-cost, no-waste, easy-to-use, method to make customized bioprinted constructs for a range of biomedical applications.
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Affiliation(s)
- Puskal Kunwar
- Biomedical, and Chemical Engineering Department, Syracuse University, Syracuse, NY 13210, United States of America
- BioInspired Institute, Syracuse, NY 13210, United States of America
| | - Ujjwal Aryal
- Biomedical, and Chemical Engineering Department, Syracuse University, Syracuse, NY 13210, United States of America
- BioInspired Institute, Syracuse, NY 13210, United States of America
| | - Arun Poudel
- Biomedical, and Chemical Engineering Department, Syracuse University, Syracuse, NY 13210, United States of America
- BioInspired Institute, Syracuse, NY 13210, United States of America
| | - Daniel Fougnier
- Biomedical, and Chemical Engineering Department, Syracuse University, Syracuse, NY 13210, United States of America
- BioInspired Institute, Syracuse, NY 13210, United States of America
| | - Zachary J Geffert
- Biomedical, and Chemical Engineering Department, Syracuse University, Syracuse, NY 13210, United States of America
- BioInspired Institute, Syracuse, NY 13210, United States of America
| | - Rui Xie
- Biomedical, and Chemical Engineering Department, Syracuse University, Syracuse, NY 13210, United States of America
- BioInspired Institute, Syracuse, NY 13210, United States of America
| | - Zhen Li
- Department of Mechanical Engineering, Clemson University, Clemson, SC 29634, United States of America
| | - Pranav Soman
- Biomedical, and Chemical Engineering Department, Syracuse University, Syracuse, NY 13210, United States of America
- BioInspired Institute, Syracuse, NY 13210, United States of America
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2
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Mamidi N, Ijadi F, Norahan MH. Leveraging the Recent Advancements in GelMA Scaffolds for Bone Tissue Engineering: An Assessment of Challenges and Opportunities. Biomacromolecules 2024; 25:2075-2113. [PMID: 37406611 DOI: 10.1021/acs.biomac.3c00279] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/07/2023]
Abstract
The field of bone tissue engineering has seen significant advancements in recent years. Each year, over two million bone transplants are performed globally, and conventional treatments, such as bone grafts and metallic implants, have their limitations. Tissue engineering offers a new level of treatment, allowing for the creation of living tissue within a biomaterial framework. Recent advances in biomaterials have provided innovative approaches to rebuilding bone tissue function after damage. Among them, gelatin methacryloyl (GelMA) hydrogel is emerging as a promising biomaterial for supporting cell proliferation and tissue regeneration, and GelMA has exhibited exceptional physicochemical and biological properties, making it a viable option for clinical translation. Various methods and classes of additives have been used in the application of GelMA for bone regeneration, with the incorporation of nanofillers or other polymers enhancing its resilience and functional performance. Despite promising results, the fabrication of complex structures that mimic the bone architecture and the provision of balanced physical properties for both cell and vasculature growth and proper stiffness for load bearing remain as challenges. In terms of utilizing osteogenic additives, the priority should be on versatile components that promote angiogenesis and osteogenesis while reinforcing the structure for bone tissue engineering applications. This review focuses on recent efforts and advantages of GelMA-based composite biomaterials for bone tissue engineering, covering the literature from the last five years.
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Affiliation(s)
- Narsimha Mamidi
- Department of Chemistry and Nanotechnology, School of Engineering and Science, Tecnológico de Monterrey, Monterrey, Nuevo León 64849, México
- Wisconsin Center for NanoBioSystems, School of Pharmacy, University of Wisconsin, Madison, Wisconsin 53705, United States
| | - Fatemeh Ijadi
- Department of Chemistry and Nanotechnology, School of Engineering and Science, Tecnológico de Monterrey, Monterrey, Nuevo León 64849, México
| | - Mohammad Hadi Norahan
- Centro de Biotecnología-FEMSA, Tecnológico de Monterrey, Monterrey, Nuevo León 64849, México
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3
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Sawyer SW, Takeda K, Alayoubi A, Mirdamadi E, Zidan A, Bauer SR, Degheidy H. 3D bioprinting optimization of human mesenchymal stromal cell laden gelatin-alginate-collagen bioink. Biomed Mater 2022; 18. [PMID: 36395510 DOI: 10.1088/1748-605x/aca3e7] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Accepted: 11/17/2022] [Indexed: 11/19/2022]
Abstract
3D bioprinting technology has gained increased attention in the regenerative medicine and tissue engineering communities over the past decade with their attempts to create functional living tissues and organsde novo. While tissues such as skin, bone, and cartilage have been successfully fabricated using 3D bioprinting, there are still many technical and process driven challenges that must be overcome before a complete tissue engineered solution is realized. Although there may never be a single adopted bioprinting process in the scientific community, adherence to optimized bioprinting protocols could reduce variability and improve precision with the goal of ensuring high quality printed constructs. Here, we report on the bioprinting of a gelatin-alginate-collagen bioink containing human mesenchymal stromal cells (hMSCs) which has been optimized to ensure printing consistency and reliability. The study consists of three phases: a pre-printing phase which focuses on bioink characterization; a printing phase which focuses on bioink extrudability/printability, construct stability, and printing accuracy; and a post-processing phase which focuses on the homogeneity and bioactivity of the encapsulated hMSC printed constructs. The results showed that eight identical constructs containing hMSCs could be reliably and accurately printed into stable cross-hatched structures with a single material preparation, and that batch-to-batch consistency was accurately maintained across all preparations. Analysis of the proliferation, morphology, and differentiation of encapsulated hMSCs within the printed constructs showed that cells were able to form large,interconnected colonies and were capable of robust adipogenic differentiation within 14 d of culturing.
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Affiliation(s)
- Stephen W Sawyer
- Center for Biologics Evaluation and Research (CBER), U.S. Food and Drug Administration, Silver Spring, MD, United States of America
| | - Kazuyo Takeda
- Center for Biologics Evaluation and Research (CBER), U.S. Food and Drug Administration, Silver Spring, MD, United States of America
| | - Alaadin Alayoubi
- Center for Drug Evaluation and Research (CDER), U.S. Food and Drug Administration, Silver Spring, MD, United States of America
| | - Eman Mirdamadi
- Department of Bioengineering, University of Maryland, College Park, MD, United States of America
| | - Ahmed Zidan
- Center for Drug Evaluation and Research (CDER), U.S. Food and Drug Administration, Silver Spring, MD, United States of America
| | - Steven R Bauer
- Center for Biologics Evaluation and Research (CBER), U.S. Food and Drug Administration, Silver Spring, MD, United States of America
| | - Heba Degheidy
- Center for Biologics Evaluation and Research (CBER), U.S. Food and Drug Administration, Silver Spring, MD, United States of America
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4
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Zhang K, Ogando C, Filip A, Zhang T, Horton JA, Soman P. In vitromodel to study confined osteocyte networks exposed to flow-induced mechanical stimuli. Biomed Mater 2022; 17:10.1088/1748-605X/aca37c. [PMID: 36384043 PMCID: PMC10642715 DOI: 10.1088/1748-605x/aca37c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Accepted: 11/16/2022] [Indexed: 11/18/2022]
Abstract
Osteocytes are considered the primary mechanical sensor in bone tissue and orchestrate the coupled bone remodeling activity of adjacent osteoblast and osteoclast cells.In vivoinvestigation of mechanically induced signal propagation through networks of interconnected osteocytes is confounded by their confinement within the mineralized bone matrix, which cannot be modeled in conventional culture systems. In this study, we developed a new model that mimics thisin vivoconfinement using gelatin methacrylate (GelMA) hydrogel or GelMA mineralized using osteoblast-like model cells. This model also enables real-time optical examination of osteocyte calcium (Ca2+) signaling dynamics in response to fluid shear stimuli cultured under confined conditions. Using this system, we discovered several distinct and previously undescribed patterns of Ca2+responses that vary across networks of interconnected osteocytes as a function of space, time and connectivity. Heterogeneity in Ca2+signaling may provide new insights into bone remodeling in response to mechanical loading. Overall, such a model can be extended to study signaling dynamics within cell networks exposed to flow-induced mechanical stimuli under confined conditions.
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Affiliation(s)
- Kairui Zhang
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY, USA, 13244
- Syracuse Biomaterials Institute, Syracuse, NY, USA, 13244
| | - Courtney Ogando
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY, USA, 13244
- Syracuse Biomaterials Institute, Syracuse, NY, USA, 13244
| | - Alex Filip
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY, USA, 13244
- Syracuse Biomaterials Institute, Syracuse, NY, USA, 13244
| | - Teng Zhang
- Syracuse Biomaterials Institute, Syracuse, NY, USA, 13244
- Department of Mechanical and Aerospace Engineering, Syracuse University, Syracuse, NY, USA, 13244
| | - Jason A. Horton
- Syracuse Biomaterials Institute, Syracuse, NY, USA, 13244
- Dept. of Orthopedic Surgery, SUNY Upstate Medical University, Syracuse, NY, USA 13210
| | - Pranav Soman
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY, USA, 13244
- Syracuse Biomaterials Institute, Syracuse, NY, USA, 13244
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5
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Vernerey FJ, Lalitha Sridhar S, Muralidharan A, Bryant SJ. Mechanics of 3D Cell-Hydrogel Interactions: Experiments, Models, and Mechanisms. Chem Rev 2021; 121:11085-11148. [PMID: 34473466 DOI: 10.1021/acs.chemrev.1c00046] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Hydrogels are highly water-swollen molecular networks that are ideal platforms to create tissue mimetics owing to their vast and tunable properties. As such, hydrogels are promising cell-delivery vehicles for applications in tissue engineering and have also emerged as an important base for ex vivo models to study healthy and pathophysiological events in a carefully controlled three-dimensional environment. Cells are readily encapsulated in hydrogels resulting in a plethora of biochemical and mechanical communication mechanisms, which recapitulates the natural cell and extracellular matrix interaction in tissues. These interactions are complex, with multiple events that are invariably coupled and spanning multiple length and time scales. To study and identify the underlying mechanisms involved, an integrated experimental and computational approach is ideally needed. This review discusses the state of our knowledge on cell-hydrogel interactions, with a focus on mechanics and transport, and in this context, highlights recent advancements in experiments, mathematical and computational modeling. The review begins with a background on the thermodynamics and physics fundamentals that govern hydrogel mechanics and transport. The review focuses on two main classes of hydrogels, described as semiflexible polymer networks that represent physically cross-linked fibrous hydrogels and flexible polymer networks representing the chemically cross-linked synthetic and natural hydrogels. In this review, we highlight five main cell-hydrogel interactions that involve key cellular functions related to communication, mechanosensing, migration, growth, and tissue deposition and elaboration. For each of these cellular functions, recent experiments and the most up to date modeling strategies are discussed and then followed by a summary of how to tune hydrogel properties to achieve a desired functional cellular outcome. We conclude with a summary linking these advancements and make the case for the need to integrate experiments and modeling to advance our fundamental understanding of cell-matrix interactions that will ultimately help identify new therapeutic approaches and enable successful tissue engineering.
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Affiliation(s)
- Franck J Vernerey
- Department of Mechanical Engineering, University of Colorado at Boulder, 1111 Engineering Drive, Boulder, Colorado 80309-0428, United States.,Materials Science and Engineering Program, University of Colorado at Boulder, 4001 Discovery Drive, Boulder, Colorado 80309-613, United States
| | - Shankar Lalitha Sridhar
- Department of Mechanical Engineering, University of Colorado at Boulder, 1111 Engineering Drive, Boulder, Colorado 80309-0428, United States
| | - Archish Muralidharan
- Materials Science and Engineering Program, University of Colorado at Boulder, 4001 Discovery Drive, Boulder, Colorado 80309-613, United States
| | - Stephanie J Bryant
- Materials Science and Engineering Program, University of Colorado at Boulder, 4001 Discovery Drive, Boulder, Colorado 80309-613, United States.,Department of Chemical and Biological Engineering, University of Colorado at Boulder, 3415 Colorado Avenue, Boulder, Colorado 80309-0596, United States.,BioFrontiers Institute, University of Colorado at Boulder, 3415 Colorado Avenue, Boulder, Colorado 80309-0596, United States
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6
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Vascularization Strategies in Bone Tissue Engineering. Cells 2021; 10:cells10071749. [PMID: 34359919 PMCID: PMC8306064 DOI: 10.3390/cells10071749] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 07/05/2021] [Accepted: 07/06/2021] [Indexed: 12/12/2022] Open
Abstract
Bone is a highly vascularized tissue, and its development, maturation, remodeling, and regeneration are dependent on a tight regulation of blood vessel supply. This condition also has to be taken into consideration in the context of the development of artificial tissue substitutes. In classic tissue engineering, bone-forming cells such as primary osteoblasts or mesenchymal stem cells are introduced into suitable scaffolds and implanted in order to treat critical-size bone defects. However, such tissue substitutes are initially avascular. Because of the occurrence of hypoxic conditions, especially in larger tissue substitutes, this leads to the death of the implanted cells. Therefore, it is necessary to devise vascularization strategies aiming at fast and efficient vascularization of implanted artificial tissues. In this review article, we present and discuss the current vascularization strategies in bone tissue engineering. These are based on the use of angiogenic growth factors, the co-implantation of blood vessel forming cells, the ex vivo microfabrication of blood vessels by means of bioprinting, and surgical methods for creating surgically transferable composite tissues.
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7
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Amler AK, Thomas A, Tüzüner S, Lam T, Geiger MA, Kreuder AE, Palmer C, Nahles S, Lauster R, Kloke L. 3D bioprinting of tissue-specific osteoblasts and endothelial cells to model the human jawbone. Sci Rep 2021; 11:4876. [PMID: 33649412 PMCID: PMC7921109 DOI: 10.1038/s41598-021-84483-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 02/15/2021] [Indexed: 02/06/2023] Open
Abstract
Jawbone differs from other bones in many aspects, including its developmental origin and the occurrence of jawbone-specific diseases like MRONJ (medication-related osteonecrosis of the jaw). Although there is a strong need, adequate in vitro models of this unique environment are sparse to date. While previous approaches are reliant e.g. on scaffolds or spheroid culture, 3D bioprinting enables free-form fabrication of complex living tissue structures. In the present work, production of human jawbone models was realised via projection-based stereolithography. Constructs were bioprinted containing primary jawbone-derived osteoblasts and vasculature-like channel structures optionally harbouring primary endothelial cells. After 28 days of cultivation in growth medium or osteogenic medium, expression of cell type-specific markers was confirmed on both the RNA and protein level, while prints maintained their overall structure. Survival of endothelial cells in the printed channels, co-cultured with osteoblasts in medium without supplementation of endothelial growth factors, was demonstrated. Constructs showed not only mineralisation, being one of the characteristics of osteoblasts, but also hinted at differentiation to an osteocyte phenotype. These results indicate the successful biofabrication of an in vitro model of the human jawbone, which presents key features of this special bone entity and hence appears promising for application in jawbone-specific research.
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Affiliation(s)
- Anna-Klara Amler
- Cellbricks GmbH, Gustav-Meyer-Allee 25, 13355, Berlin, Germany. .,Department of Medical Biotechnology, Technische Universität Berlin, Gustav-Meyer-Allee 25, 13355, Berlin, Germany.
| | - Alexander Thomas
- Cellbricks GmbH, Gustav-Meyer-Allee 25, 13355, Berlin, Germany.,Department of Medical Biotechnology, Technische Universität Berlin, Gustav-Meyer-Allee 25, 13355, Berlin, Germany
| | - Selin Tüzüner
- Cellbricks GmbH, Gustav-Meyer-Allee 25, 13355, Berlin, Germany.,Department of Medical Biotechnology, Technische Universität Berlin, Gustav-Meyer-Allee 25, 13355, Berlin, Germany
| | - Tobias Lam
- Cellbricks GmbH, Gustav-Meyer-Allee 25, 13355, Berlin, Germany
| | | | - Anna-Elisabeth Kreuder
- Cellbricks GmbH, Gustav-Meyer-Allee 25, 13355, Berlin, Germany.,Department of Medical Biotechnology, Technische Universität Berlin, Gustav-Meyer-Allee 25, 13355, Berlin, Germany
| | - Chris Palmer
- Cellbricks GmbH, Gustav-Meyer-Allee 25, 13355, Berlin, Germany
| | - Susanne Nahles
- Department of Oral- and Maxillofacial Surgery, Charité Campus Virchow, Augustenburger Platz 1, 13353, Berlin, Germany
| | - Roland Lauster
- Department of Medical Biotechnology, Technische Universität Berlin, Gustav-Meyer-Allee 25, 13355, Berlin, Germany
| | - Lutz Kloke
- Cellbricks GmbH, Gustav-Meyer-Allee 25, 13355, Berlin, Germany
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8
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Askari M, Afzali Naniz M, Kouhi M, Saberi A, Zolfagharian A, Bodaghi M. Recent progress in extrusion 3D bioprinting of hydrogel biomaterials for tissue regeneration: a comprehensive review with focus on advanced fabrication techniques. Biomater Sci 2021; 9:535-573. [DOI: 10.1039/d0bm00973c] [Citation(s) in RCA: 121] [Impact Index Per Article: 40.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Over the last decade, 3D bioprinting has received immense attention from research communities to bridge the divergence between artificially engineered tissue constructs and native tissues.
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Affiliation(s)
- Mohsen Askari
- Department of Engineering
- School of Science and Technology
- Nottingham Trent University
- Nottingham NG11 8NS
- UK
| | - Moqaddaseh Afzali Naniz
- Department of Engineering
- School of Science and Technology
- Nottingham Trent University
- Nottingham NG11 8NS
- UK
| | - Monireh Kouhi
- Biomaterials Research Group
- Department of Materials Engineering
- Isfahan University of Technology
- Isfahan
- Iran
| | - Azadeh Saberi
- Nanotechnology and Advanced Materials Department
- Materials and Energy Research Center
- Tehran
- Iran
| | | | - Mahdi Bodaghi
- Department of Engineering
- School of Science and Technology
- Nottingham Trent University
- Nottingham NG11 8NS
- UK
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9
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GhavamiNejad A, Ashammakhi N, Wu XY, Khademhosseini A. Crosslinking Strategies for 3D Bioprinting of Polymeric Hydrogels. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2020; 16:e2002931. [PMID: 32734720 PMCID: PMC7754762 DOI: 10.1002/smll.202002931] [Citation(s) in RCA: 131] [Impact Index Per Article: 32.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2020] [Indexed: 05/15/2023]
Abstract
Three-dimensional (3D) bioprinting has recently advanced as an important tool to produce viable constructs that can be used for regenerative purposes or as tissue models. To develop biomimetic and sustainable 3D constructs, several important processing aspects need to be considered, among which crosslinking is most important for achieving desirable biomechanical stability of printed structures, which is reflected in subsequent behavior and use of these constructs. In this work, crosslinking methods used in 3D bioprinting studies are reviewed, parameters that affect bioink chemistry are discussed, and the potential toward improving crosslinking outcomes and construct performance is highlighted. Furthermore, current challenges and future prospects are discussed. Due to the direct connection between crosslinking methods and properties of 3D bioprinted structures, this Review can provide a basis for developing necessary modifications to the design and manufacturing process of advanced tissue-like constructs in future.
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Affiliation(s)
- Amin GhavamiNejad
- Advanced Pharmaceutics and Drug Delivery Laboratory, Leslie L. Dan Faculty of Pharmacy, University of Toronto, Toronto, Canada
| | - Nureddin Ashammakhi
- Center for Minimally Invasive Therapeutics, California NanoSystems Institute (CNSI), University of California - Los Angeles, Los Angeles, California, USA
- Department of Radiological Sciences, University of California - Los Angeles, Los Angeles, California, USA
- Department of Bioengineering, University of California - Los Angeles, Los Angeles, California, USA
| | - Xiao Yu Wu
- Advanced Pharmaceutics and Drug Delivery Laboratory, Leslie L. Dan Faculty of Pharmacy, University of Toronto, Toronto, Canada
| | - Ali Khademhosseini
- Center for Minimally Invasive Therapeutics, California NanoSystems Institute (CNSI), University of California - Los Angeles, Los Angeles, California, USA
- Department of Radiological Sciences, University of California - Los Angeles, Los Angeles, California, USA
- Department of Bioengineering, University of California - Los Angeles, Los Angeles, California, USA
- Department of Chemical and Biomolecular Engineering, University of California - Los Angeles, Los Angeles, California, USA
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10
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Sawyer SW, Zhang K, Horton JA, Soman P. Perfusion-based co-culture model system for bone tissue engineering. AIMS BIOENGINEERING 2020; 7:91-105. [PMID: 33163623 PMCID: PMC7643915 DOI: 10.3934/bioeng.2020009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
In this work, we report on a perfusion-based co-culture system that could be used for bone tissue engineering applications. The model system is created using a combination of Primary Human Umbilical Vein Endothelial Cells (HUVECs) and osteoblast-like Saos-2 cells encapsulated within a Gelatin Methacrylate (GelMA)-collagen hydrogel blend contained within 3D printed, perfusable constructs. The constructs contain dual channels, within a custom-built bioreactor, that were perfused with osteogenic media for up to two weeks in order to induce mineral deposition. Mineral deposition in constructs containing only HUVECs, only Saos-2 cells, or a combination thereof was quantified by microCT to determine if the combination of endothelial cells and bone-like cells increased mineral deposition. Histological and fluorescent staining was used to verify mineral deposition and cellular function both along and between the perfused channels. While there was not a quantifiable difference in the amount of mineral deposited in Saos-2 only versus Saos-2 plus HUVEC samples, the location of the deposited mineral differed dramatically between the groups and indicated that the addition of HUVECs within the GelMA matrix allowed Saos-2 cells, in diffusion limited regions of the construct, to deposit bone mineral. This work serves as a model on how to create perfusable bone tissue engineering constructs using a combination of 3D printing and cellular co-cultures.
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Affiliation(s)
- Stephen W. Sawyer
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY, USA
| | - Kairui Zhang
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY, USA
| | - Jason A. Horton
- Department of Orthopedic Surgery, SUNY Upstate Medical University, Syracuse, NY, USA
| | - Pranav Soman
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY, USA
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11
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Li Z, Ramos A, Li MC, Li Z, Bhatta S, Jeyaseelan A, Li Y, Wu Q, Yao S, Xu J. Improvement of cell deposition by self-absorbent capability of freeze-dried 3D-bioprinted scaffolds derived from cellulose material-alginate hydrogels. Biomed Phys Eng Express 2020; 6:045009. [PMID: 33444270 DOI: 10.1088/2057-1976/ab8fc6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Cell-laden printing is the most commonly used approach in 3D bioprinting. One of the major drawbacks of cell-laden printing is that cell viability is highly affected by the extrusion pressure and shear force in the printing process. We present a new cell-deposition method by using the superabsorbent capability of 3D printed scaffolds with four ink formations: 20:10 nanocrystal/alginate (NCA 20/10), 20:10 nanofiber/alginate (NFA 20/10), 20:02 nanocrystal/alginate (NCA 20/02) and 20:02 nanofiber/alginate (NFA 20/02). Limited pores were observed from the surface of inherent NCA and NFA scaffolds, which may limit the numbers of cells to enter into the scaffolds. Therefore, we designed a dual-porous (DP) structure to connect the inherent pores (IPs) to the scaffold surface. Due to these porous structures, NCA and NFA scaffolds exhibit an excellent capability to absorb cell suspension, which may be used for depositing cells to 3D-printed scaffolds, namely self-absorbent (SA) deposition. Compared to the conventional top-loading (TL) method, the SA method had more uniform cell distributions in the entire 3D-printed scaffolds and higher efficiency of cell deposition. For the TL method, DP scaffold exhibited a more uniform cell distribution, which may provide a better microenvironment for the cells in comparison to the IP scaffold. For both cell loading methods, a rapid increase of cell number was observed in the first 4 days of culture in the 3D-printed NCA and NFA structures. NFA 20/02 exhibits the best cell viability compared to the other three inks. In conclusion, the SA method may serve as a new approach for loading cells in cell-free 3D-bioprinting, and DP design could improve the efficiency of the cell deposition.
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Affiliation(s)
- Zhongqiang Li
- Division of Electrical and Computer Engineering, College of Engineering, Louisiana State University, Baton Rouge, LA 70803, United States of America
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12
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Shahabipour F, Ashammakhi N, Oskuee RK, Bonakdar S, Hoffman T, Shokrgozar MA, Khademhosseini A. Key components of engineering vascularized 3-dimensional bioprinted bone constructs. Transl Res 2020; 216:57-76. [PMID: 31526771 DOI: 10.1016/j.trsl.2019.08.010] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2019] [Revised: 08/28/2019] [Accepted: 08/30/2019] [Indexed: 12/16/2022]
Abstract
Vascularization has a pivotal role in engineering successful tissue constructs. However, it remains a major hurdle of bone tissue engineering, especially in clinical applications for the treatment of large bone defects. Development of vascularized and clinically-relevant engineered bone substitutes with sufficient blood supply capable of maintaining implant viability and supporting subsequent host tissue integration remains a major challenge. Since only cells that are 100-200 µm from blood vessels can receive oxygen through diffusion, engineered constructs that are thicker than 400 µm face a challenging oxygenation problem. Following implantation in vivo, spontaneous ingrowth of capillaries in thick engineered constructs is too slow. Thus, it is critical to provide optimal conditions to support vascularization in engineered bone constructs. To achieve this, an in-depth understanding of the mechanisms of angiogenesis and bone development is required. In addition, it is also important to mimic the physiological milieu of native bone to fabricate more successful vascularized bone constructs. Numerous applications of engineered vascularization with cell-and/or microfabrication-based approaches seek to meet these aims. Three-dimensional (3D) printing promises to create patient-specific bone constructs in the future. In this review, we discuss the major components of fabricating vascularized 3D bioprinted bone constructs, analyze their related challenges, and highlight promising future trends.
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Affiliation(s)
- Fahimeh Shahabipour
- National cell bank of Iran, Pasteur Institute of Iran, Tehran, Iran; Center for Minimally Invasive Therapeutics (C-MIT), University of California, Los Angeles, Los Angeles, California; California NanoSystems Institute (CNSI), University of California, Los Angeles, Los Angeles, California; Department of Bioengineering, University of California, Los Angeles, Los Angeles, California
| | - Nureddin Ashammakhi
- Center for Minimally Invasive Therapeutics (C-MIT), University of California, Los Angeles, Los Angeles, California; California NanoSystems Institute (CNSI), University of California, Los Angeles, Los Angeles, California; Department of Bioengineering, University of California, Los Angeles, Los Angeles, California; Department of Radiological Sciences, University of California, Los Angeles, Los Angeles, California
| | - Reza K Oskuee
- Targeted Drug Delivery Research Center, Institute of Pharmaceutical Technology, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Shahin Bonakdar
- National cell bank of Iran, Pasteur Institute of Iran, Tehran, Iran
| | - Tyler Hoffman
- Center for Minimally Invasive Therapeutics (C-MIT), University of California, Los Angeles, Los Angeles, California; California NanoSystems Institute (CNSI), University of California, Los Angeles, Los Angeles, California; Department of Bioengineering, University of California, Los Angeles, Los Angeles, California
| | | | - Ali Khademhosseini
- Center for Minimally Invasive Therapeutics (C-MIT), University of California, Los Angeles, Los Angeles, California; California NanoSystems Institute (CNSI), University of California, Los Angeles, Los Angeles, California; Department of Bioengineering, University of California, Los Angeles, Los Angeles, California; Department of Radiological Sciences, University of California, Los Angeles, Los Angeles, California; Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, Los Angeles, California.
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13
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Sego TJ, Prideaux M, Sterner J, McCarthy BP, Li P, Bonewald LF, Ekser B, Tovar A, Jeshua Smith L. Computational fluid dynamic analysis of bioprinted self-supporting perfused tissue models. Biotechnol Bioeng 2019; 117:798-815. [PMID: 31788785 PMCID: PMC7015804 DOI: 10.1002/bit.27238] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Revised: 11/12/2019] [Accepted: 11/22/2019] [Indexed: 01/11/2023]
Abstract
Natural tissues are incorporated with vasculature, which is further integrated with a cardiovascular system responsible for driving perfusion of nutrient‐rich oxygenated blood through the vasculature to support cell metabolism within most cell‐dense tissues. Since scaffold‐free biofabricated tissues being developed into clinical implants, research models, and pharmaceutical testing platforms should similarly exhibit perfused tissue‐like structures, we generated a generalizable biofabrication method resulting in self‐supporting perfused (SSuPer) tissue constructs incorporated with perfusible microchannels and integrated with the modular FABRICA perfusion bioreactor. As proof of concept, we perfused an MLO‐A5 osteoblast‐based SSuPer tissue in the FABRICA. Although our resulting SSuPer tissue replicated vascularization and perfusion observed in situ, supported its own weight, and stained positively for mineral using Von Kossa staining, our in vitro results indicated that computational fluid dynamics (CFD) should be used to drive future construct design and flow application before further tissue biofabrication and perfusion. We built a CFD model of the SSuPer tissue integrated in the FABRICA and analyzed flow characteristics (net force, pressure distribution, shear stress, and oxygen distribution) through five SSuPer tissue microchannel patterns in two flow directions and at increasing flow rates. Important flow parameters include flow direction, fully developed flow, and tissue microchannel diameters matched and aligned with bioreactor flow channels. We observed that the SSuPer tissue platform is capable of providing direct perfusion to tissue constructs and proper culture conditions (oxygenation, with controllable shear and flow rates), indicating that our approach can be used to biofabricate tissue representing primary tissues and that we can model the system in silico.
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Affiliation(s)
- T J Sego
- Department of Intelligent Systems Engineering, Indiana University, Bloomington, Indiana
| | - Matthew Prideaux
- Indiana Center for Musculoskeletal Health, Indiana University, Indianapolis, Indiana.,Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana
| | - Jane Sterner
- Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, Indiana.,3D Bioprinting Core, Indiana University School of Medicine, Indianapolis, Indiana
| | - Brian Paul McCarthy
- Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, Indiana
| | - Ping Li
- Division of Transplant Surgery, Department of Surgery, Indiana University School of Medicine, Indianapolis, Indiana
| | - Lynda F Bonewald
- Indiana Center for Musculoskeletal Health, Indiana University, Indianapolis, Indiana.,Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana.,Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, Indiana
| | - Burcin Ekser
- Division of Transplant Surgery, Department of Surgery, Indiana University School of Medicine, Indianapolis, Indiana
| | - Andres Tovar
- Department of Mechanical and Energy Engineering, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana
| | - Lester Jeshua Smith
- Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, Indiana.,3D Bioprinting Core, Indiana University School of Medicine, Indianapolis, Indiana
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14
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Soucy JR, Askaryan J, Diaz D, Koppes AN, Annabi N, Koppes RA. Glial cells influence cardiac permittivity as evidenced through in vitro and in silico models. Biofabrication 2019; 12:015014. [PMID: 31593932 PMCID: PMC11062241 DOI: 10.1088/1758-5090/ab4c0a] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Excitation-contraction (EC) coupling in the heart has, until recently, been solely accredited to cardiomyocytes. The inherent complexities of the heart make it difficult to examine non-muscle contributions to contraction in vivo, and conventional in vitro models fail to capture multiple features and cellular heterogeneity of the myocardium. Here, we report on the development of a 3D cardiac μTissue to investigate changes in the cellular composition of native myocardium in vitro. Cells are encapsulated within micropatterned gelatin-based hydrogels formed via visible light photocrosslinking. This system enables spatial control of the microarchitecture, perturbation of the cellular composition, and functional measures of EC coupling via video microscopy and a custom algorithm to quantify beat frequency and degree of coordination. To demonstrate the robustness of these tools and evaluate the impact of altered cell population densities on cardiac μTissues, contractility and cell morphology were assessed with the inclusion of exogenous non-myelinating Schwann cells (SCs). Results demonstrate that the addition of exogenous SCs alter cardiomyocyte EC, profoundly inhibiting the response to electrical pacing. Computational modeling of connexin-mediated coupling suggests that SCs impact cardiomyocyte resting potential and rectification following depolarization. Cardiac μTissues hold potential for examining the role of cellular heterogeneity in heart health, pathologies, and cellular therapies.
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Affiliation(s)
- Jonathan R Soucy
- Department of Chemical Engineering, Northeastern University, Boston, MA 02115, United States of America
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15
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Kunwar P, Xiong Z, Zhu Y, Li H, Filip A, Soman P. Hybrid Laser Printing of 3D, Multiscale, Multimaterial Hydrogel Structures. ADVANCED OPTICAL MATERIALS 2019; 7:1900656. [PMID: 33688458 PMCID: PMC7938640 DOI: 10.1002/adom.201900656] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Indexed: 05/18/2023]
Abstract
Fabrication of multiscale, multi-material three-dimensional (3D) structures at high resolution is difficult using current technologies. This is especially significant when working with hydrated and mechanically weak hydrogel materials. In this work, a new hybrid laser printing (HLP) technology is reported to print complex, multiscale, multimaterial, 3D hydrogel structures with microscale resolution. This technique of fabrication utilizes sequential additive and subtractive modes of material fabrication, that are typically considered as mutually exclusive due to differences in their material processing conditions. Further, compared to current laser writing systems that enforce stringent processing depth limits, HLP is shown to fabricate structures at any depth inside the material. As a proof-of-principle, a Mayan Pyramid with embedded cube-frame is printed using model synthetic polyethylene glycol diacrylate (PEGDA) hydrogel. Printing of ready-to-use open-well chips with embedded microchannels is also demonstrated using PEGDA and gelatin methacrylate (GelMA) hydrogels for potential applications in biomedical sciences. Next, HLP is used in additive and additive modes to print multiscale 3D structures spanning in size from centimeter to micrometers within minutes, which is followed by printing of 3D, multi-material, multiscale structures using this technology. Overall, this work demonstrates that HLP's fabrication versatility can potentially offer a unique opportunity for a range of applications in optics and photonics, biomedical sciences, microfluidics, soft robotics, etc.
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Affiliation(s)
- Puskal Kunwar
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY, 13244, USA
| | - Zheng Xiong
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY, 13244, USA
| | - Yin Zhu
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY, 13244, USA
| | - Haiyan Li
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY, 13244, USA
| | - Alex Filip
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY, 13244, USA
| | - Pranav Soman
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY, 13244, USA
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16
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Nguyen TU, Watkins KE, Kishore V. Photochemically crosslinked cell-laden methacrylated collagen hydrogels with high cell viability and functionality. J Biomed Mater Res A 2019; 107:1541-1550. [PMID: 30882990 PMCID: PMC6527486 DOI: 10.1002/jbm.a.36668] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2018] [Revised: 01/30/2019] [Accepted: 02/21/2019] [Indexed: 12/19/2022]
Abstract
Irgacure 2959 (I2959) is widely used as a photoinitiator for photochemical crosslinking of hydrogels. However, the free radicals generated from I2959 have been reported to be highly cytotoxic. In this study, methacrylated collagen (CMA) hydrogels were photochemically crosslinked using two different photoinitiators (i.e., I2959 and VA086) and the effect of photoinitiator type, photoinitiator concentration (i.e., 0.02 and 0.1%) and crosslinking time (1 and 10 min) on gel morphology, compressive modulus, and stability were investigated. In addition, Saos-2 cells were encapsulated within the hydrogels and the effect of photochemical crosslinking conditions on cell viability, metabolic activity, and osteoblast functionality was assessed. Scanning electron microscopy imaging showed that photochemical crosslinking decreased the porosity of the hydrogels resulting in decrease in water retention ability compared to uncrosslinked hydrogels. On the other hand, photochemical crosslinking improved the stability of CMA hydrogels (p < 0.05). Uniaxial compression tests showed that increasing the photoinitiator concentration significantly improved the compressive modulus of CMA hydrogels (p < 0.05). Results from the live-dead assay showed that VA086 crosslinked hydrogels exhibited higher cell viability compared to I2959 (p < 0.05) crosslinked hydrogels indicating that VA086 is more cytocompatible compared to I2959. Furthermore, Alizarin Red S staining revealed a significantly more pronounced cell-mediated mineralization on VA086 crosslinked hydrogels (p < 0.05) indicating that Saos-2 cells retain their normal functionality in the presence of VA086. In summary, these results indicate that VA086 is a more biocompatible photoinitiator compared to I2959 for the generation of photochemically crosslinked CMA hydrogels for tissue engineering applications. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2019.
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Affiliation(s)
- Thuy-Uyen Nguyen
- Department of Biomedical and Chemical Engineering and Sciences, Florida Institute of Technology, Melbourne, FL 32901
| | - Kori E. Watkins
- Department of Biomedical and Chemical Engineering and Sciences, Florida Institute of Technology, Melbourne, FL 32901
| | - Vipuil Kishore
- Department of Biomedical and Chemical Engineering and Sciences, Florida Institute of Technology, Melbourne, FL 32901
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17
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Ramos R, Zhang K, Quinn D, Sawyer SW, Mcloughlin S, Soman P. Measuring Changes in Electrical Impedance During Cell-Mediated Mineralization. Bioelectricity 2019; 1:73-84. [PMID: 34471812 PMCID: PMC8370274 DOI: 10.1089/bioe.2018.0008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Background: The fundamental electrical properties of bone have been attributed to the organic collagen and the inorganic mineral component; however, contributions of individual components within bone tissue toward the measured electrical properties are not known. In our study, we investigated the electrical properties of cell-mediated mineral deposition process and compared our results with cell-free mineralization. Materials and Methods: Saos-2 cells encapsulated within gelatin methacrylate (GelMA) hydrogels were chemically stimulated in osteogenic medium for a period of 4 weeks. The morphology, composition, and mechanical properties of the mineralized constructs were characterized using bright-field imaging, scanning electron microscopy (SEM) energy-dispersive X-ray spectroscopy, Fourier-transform infrared spectroscopy (FITR), nuclear magnetic resonance spectroscopy (NMR), micro-CT, immunostaining, and mechanical compression tests. In parallel, a custom-made device was used to measure the electrical impedance of mineralized constructs. All results were compared with cell-free GelMA hydrogels mineralized through the simulated body fluid approach. Results: Results demonstrate a decrease in the electrical impedance of deposited mineral in both cell-mineralized and cell-free mineralized samples. Conclusions: This study establishes a model system to investigate in vivo and in vitro mineralization processes.
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Affiliation(s)
- Rafael Ramos
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, New York
- Syracuse Biomaterial Institute, Syracuse, New York
| | - Kairui Zhang
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, New York
- Syracuse Biomaterial Institute, Syracuse, New York
| | - David Quinn
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, New York
- Syracuse Biomaterial Institute, Syracuse, New York
| | - Stephen W. Sawyer
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, New York
- Syracuse Biomaterial Institute, Syracuse, New York
| | - Shannon Mcloughlin
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, New York
- Syracuse Biomaterial Institute, Syracuse, New York
| | - Pranav Soman
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, New York
- Syracuse Biomaterial Institute, Syracuse, New York
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18
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Sun M, Sun X, Wang Z, Guo S, Yu G, Yang H. Synthesis and Properties of Gelatin Methacryloyl (GelMA) Hydrogels and Their Recent Applications in Load-Bearing Tissue. Polymers (Basel) 2018; 10:E1290. [PMID: 30961215 PMCID: PMC6401825 DOI: 10.3390/polym10111290] [Citation(s) in RCA: 199] [Impact Index Per Article: 33.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2018] [Revised: 11/15/2018] [Accepted: 11/16/2018] [Indexed: 12/17/2022] Open
Abstract
Photocrosslinked gelatin methacryloyl (GelMA) hydrogels have attracted great concern in the biomedical field because of their good biocompatibility and tunable physicochemical properties. Herein, different approaches to synthesize GelMA were introduced, especially, the typical method using UV light to crosslink the gelatin-methacrylic anhydride (MA) precursor was introduced in detail. In addition, the traditional and cutting-edge technologies to characterize the properties of GelMA hydrogels and GelMA prepolymer were also overviewed and compared. Furthermore, the applications of GelMA hydrogels in cell culture and tissue engineering especially in the load-bearing tissue (bone and cartilage) were summarized, followed by concluding remarks.
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Affiliation(s)
- Mingyue Sun
- School of Fundamental Sciences, China Medical University, Shenyang 110122, China.
| | - Xiaoting Sun
- School of Fundamental Sciences, China Medical University, Shenyang 110122, China.
| | - Ziyuan Wang
- The Queen's University of Belfast Joint College, China Medical University, Shenyang 110122, China.
| | - Shuyu Guo
- The Queen's University of Belfast Joint College, China Medical University, Shenyang 110122, China.
| | - Guangjiao Yu
- The Queen's University of Belfast Joint College, China Medical University, Shenyang 110122, China.
| | - Huazhe Yang
- School of Fundamental Sciences, China Medical University, Shenyang 110122, China.
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