1
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Liu Y, Cui X, Lu R, Yang D, Ai Y, Cheow LF. Digital Sort-Enabled Counting Allows Absolute Electrical Quantification of Target Nucleic Acid. ACS Sens 2024; 9:2695-2702. [PMID: 38747895 DOI: 10.1021/acssensors.4c00750] [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] [Indexed: 05/25/2024]
Abstract
Quantitative nucleic acid amplification tests are of great importance for diagnostics, but current approaches require complex and costly optical setups that limit their nonlaboratory applications. Herein we describe the implementation of a microfluidics platform that can perform binary DNA-amplification-activated droplet sorting. The digital sort-enabled counting (DISCO) platform enables label-free absolute quantification of the nucleic acid. This is achieved by provoking a pH change in droplets through a loop-mediated isothermal amplification (LAMP) reaction, followed by using sorting by interfacial tension (SIFT) to direct positive and negative droplets to different outlets. With the use of on-chip electrodes at both outlets, we demonstrate that the digital electrical counting of target DNA and RNA can be realized. DISCO is a promising approach for realizing sensitive nucleic acid quantification in point-of-care settings.
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Affiliation(s)
- Yi Liu
- Department of Biomedical Engineering and Institute for Health Innovation and Technology, National University of Singapore, Singapore 119077, Singapore
| | - Xu Cui
- Department of Biomedical Engineering and Institute for Health Innovation and Technology, National University of Singapore, Singapore 119077, Singapore
| | - Ri Lu
- Department of Biomedical Engineering and Institute for Health Innovation and Technology, National University of Singapore, Singapore 119077, Singapore
| | - Dahou Yang
- Critical Analytics for Manufacturing Personalized Medicine, Singapore MIT Alliance for Research and Technology, Singapore 138602, Singapore
| | - Ye Ai
- Critical Analytics for Manufacturing Personalized Medicine, Singapore MIT Alliance for Research and Technology, Singapore 138602, Singapore
- Pillar of Engineering Product Development, Singapore University of Technology and Design, Singapore 387372, Singapore
| | - Lih Feng Cheow
- Department of Biomedical Engineering and Institute for Health Innovation and Technology, National University of Singapore, Singapore 119077, Singapore
- Critical Analytics for Manufacturing Personalized Medicine, Singapore MIT Alliance for Research and Technology, Singapore 138602, Singapore
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2
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Vilela de Sousa I, Ferreira MJS, Bebiano LB, Simões S, Matos AF, Pereira RF, Granja PL. Skin models of cutaneous toxicity, transdermal transport and wound repair. BURNS & TRAUMA 2023; 11:tkad014. [PMID: 37520659 PMCID: PMC10382248 DOI: 10.1093/burnst/tkad014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 01/09/2023] [Accepted: 03/02/2023] [Indexed: 08/01/2023]
Abstract
Skin is widely used as a drug delivery route due to its easy access and the possibility of using relatively painless methods for the administration of bioactive molecules. However, the barrier properties of the skin, along with its multilayer structure, impose severe restrictions on drug transport and bioavailability. Thus, bioengineered models aimed at emulating the skin have been developed not only for optimizing the transdermal transport of different drugs and testing the safety and toxicity of substances but also for understanding the biological processes behind skin wounds. Even though in vivo research is often preferred to study biological processes involving the skin, in vitro and ex vivo strategies have been gaining increasing relevance in recent years. Indeed, there is a noticeably increasing adoption of in vitro and ex vivo methods by internationally accepted guidelines. Furthermore, microfluidic organ-on-a-chip devices are nowadays emerging as valuable tools for functional and behavioural skin emulation. Challenges in miniaturization, automation and reliability still need to be addressed in order to create skin models that can predict skin behaviour in a robust, high-throughput manner, while being compliant with regulatory issues, standards and guidelines. In this review, skin models for transdermal transport, wound repair and cutaneous toxicity will be discussed with a focus on high-throughput strategies. Novel microfluidic strategies driven by advancements in microfabrication technologies will also be revised as a way to improve the efficiency of existing models, both in terms of complexity and throughput.
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Affiliation(s)
| | | | - Luís B Bebiano
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Dr. Manuel Pereira da Silva, 4200-393 Porto, Portugal
- INEB - Instituto de Engenharia Biomédica, Universidade do Porto, Rua do Campo Alegre, 823, 4150-180 Porto, Portugal
- ISEP - Instituto Superior de Engenharia do Porto, Universidade do Porto, Rua Dr. António Bernardino de Almeida 431, 4200-072 Porto, Portugal
| | - Sandra Simões
- iMed.ULisboa, Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal
| | - Ana Filipa Matos
- Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal
| | - Rúben F Pereira
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Dr. Manuel Pereira da Silva, 4200-393 Porto, Portugal
- INEB - Instituto de Engenharia Biomédica, Universidade do Porto, Rua do Campo Alegre, 823, 4150-180 Porto, Portugal
- ICBAS – Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal
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3
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Meyer T, Ramirez C, Tamasi MJ, Gormley AJ. A User's Guide to Machine Learning for Polymeric Biomaterials. ACS POLYMERS AU 2023; 3:141-157. [PMID: 37065715 PMCID: PMC10103193 DOI: 10.1021/acspolymersau.2c00037] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 10/27/2022] [Accepted: 10/27/2022] [Indexed: 11/18/2022]
Abstract
The development of novel biomaterials is a challenging process, complicated by a design space with high dimensionality. Requirements for performance in the complex biological environment lead to difficult a priori rational design choices and time-consuming empirical trial-and-error experimentation. Modern data science practices, especially artificial intelligence (AI)/machine learning (ML), offer the promise to help accelerate the identification and testing of next-generation biomaterials. However, it can be a daunting task for biomaterial scientists unfamiliar with modern ML techniques to begin incorporating these useful tools into their development pipeline. This Perspective lays the foundation for a basic understanding of ML while providing a step-by-step guide to new users on how to begin implementing these techniques. A tutorial Python script has been developed walking users through the application of an ML pipeline using data from a real biomaterial design challenge based on group's research. This tutorial provides an opportunity for readers to see and experiment with ML and its syntax in Python. The Google Colab notebook can be easily accessed and copied from the following URL: www.gormleylab.com/MLcolab.
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Affiliation(s)
- Travis
A. Meyer
- Department of Biomedical
Engineering, Rutgers, The State University
of New Jersey, Piscataway, New Jersey 08854, United States
| | - Cesar Ramirez
- Department of Biomedical
Engineering, Rutgers, The State University
of New Jersey, Piscataway, New Jersey 08854, United States
| | - Matthew J. Tamasi
- Department of Biomedical
Engineering, Rutgers, The State University
of New Jersey, Piscataway, New Jersey 08854, United States
| | - Adam J. Gormley
- Department of Biomedical
Engineering, Rutgers, The State University
of New Jersey, Piscataway, New Jersey 08854, United States
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4
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Wu J, Fang H, Zhang J, Yan S. Modular microfluidics for life sciences. J Nanobiotechnology 2023; 21:85. [PMID: 36906553 PMCID: PMC10008080 DOI: 10.1186/s12951-023-01846-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Accepted: 03/06/2023] [Indexed: 03/13/2023] Open
Abstract
The advancement of microfluidics has enabled numerous discoveries and technologies in life sciences. However, due to the lack of industry standards and configurability, the design and fabrication of microfluidic devices require highly skilled technicians. The diversity of microfluidic devices discourages biologists and chemists from applying this technique in their laboratories. Modular microfluidics, which integrates the standardized microfluidic modules into a whole, complex platform, brings the capability of configurability to conventional microfluidics. The exciting features, including portability, on-site deployability, and high customization motivate us to review the state-of-the-art modular microfluidics and discuss future perspectives. In this review, we first introduce the working mechanisms of the basic microfluidic modules and evaluate their feasibility as modular microfluidic components. Next, we explain the connection approaches among these microfluidic modules, and summarize the advantages of modular microfluidics over integrated microfluidics in biological applications. Finally, we discuss the challenge and future perspectives of modular microfluidics.
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Affiliation(s)
- Jialin Wu
- Institute for Advanced Study, Shenzhen University, Shenzhen, 518060, China
- Nanophotonics Research Center, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen, China
| | - Hui Fang
- Nanophotonics Research Center, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen, China
| | - Jun Zhang
- Queensland Micro and Nanotechnology Centre, Griffith University, Brisbane, QLD, 4111, Australia
| | - Sheng Yan
- Institute for Advanced Study, Shenzhen University, Shenzhen, 518060, China.
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5
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Filippi M, Buchner T, Yasa O, Weirich S, Katzschmann RK. Microfluidic Tissue Engineering and Bio-Actuation. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2108427. [PMID: 35194852 DOI: 10.1002/adma.202108427] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 02/07/2022] [Indexed: 06/14/2023]
Abstract
Bio-hybrid technologies aim to replicate the unique capabilities of biological systems that could surpass advanced artificial technologies. Soft bio-hybrid robots consist of synthetic and living materials and have the potential to self-assemble, regenerate, work autonomously, and interact safely with other species and the environment. Cells require a sufficient exchange of nutrients and gases, which is guaranteed by convection and diffusive transport through liquid media. The functional development and long-term survival of biological tissues in vitro can be improved by dynamic flow culture, but only microfluidic flow control can develop tissue with fine structuring and regulation at the microscale. Full control of tissue growth at the microscale will eventually lead to functional macroscale constructs, which are needed as the biological component of soft bio-hybrid technologies. This review summarizes recent progress in microfluidic techniques to engineer biological tissues, focusing on the use of muscle cells for robotic bio-actuation. Moreover, the instances in which bio-actuation technologies greatly benefit from fusion with microfluidics are highlighted, which include: the microfabrication of matrices, biomimicry of cell microenvironments, tissue maturation, perfusion, and vascularization.
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Affiliation(s)
- Miriam Filippi
- Soft Robotics Laboratory, ETH Zurich, Tannenstrasse 3, Zurich, 8092, Switzerland
| | - Thomas Buchner
- Soft Robotics Laboratory, ETH Zurich, Tannenstrasse 3, Zurich, 8092, Switzerland
| | - Oncay Yasa
- Soft Robotics Laboratory, ETH Zurich, Tannenstrasse 3, Zurich, 8092, Switzerland
| | - Stefan Weirich
- Soft Robotics Laboratory, ETH Zurich, Tannenstrasse 3, Zurich, 8092, Switzerland
| | - Robert K Katzschmann
- Soft Robotics Laboratory, ETH Zurich, Tannenstrasse 3, Zurich, 8092, Switzerland
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6
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Bang S, Hwang KS, Jeong S, Cho IJ, Choi N, Kim J, Kim HN. Engineered neural circuits for modeling brain physiology and neuropathology. Acta Biomater 2021; 132:379-400. [PMID: 34157452 DOI: 10.1016/j.actbio.2021.06.024] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 05/16/2021] [Accepted: 06/14/2021] [Indexed: 12/14/2022]
Abstract
The neural circuits of the central nervous system are the regulatory pathways for feeling, motion control, learning, and memory, and their dysfunction is closely related to various neurodegenerative diseases. Despite the growing demand for the unraveling of the physiology and functional connectivity of the neural circuits, their fundamental investigation is hampered because of the inability to access the components of neural circuits and the complex microenvironment. As an alternative approach, in vitro human neural circuits show principles of in vivo human neuronal circuit function. They allow access to the cellular compartment and permit real-time monitoring of neural circuits. In this review, we summarize recent advances in reconstituted in vitro neural circuits using engineering techniques. To this end, we provide an overview of the fabrication techniques and methods for stimulation and measurement of in vitro neural circuits. Subsequently, representative examples of in vitro neural circuits are reviewed with a particular focus on the recapitulation of structures and functions observed in vivo, and we summarize their application in the study of various brain diseases. We believe that the in vitro neural circuits can help neuroscience and the neuropharmacology. STATEMENT OF SIGNIFICANCE: Despite the growing demand to unravel the physiology and functional connectivity of the neural circuits, the studies on the in vivo neural circuits are frequently limited due to the poor accessibility. Furthermore, single neuron-based analysis has an inherent limitation in that it does not reflect the full spectrum of the neural circuit physiology. As an alternative approach, in vitro engineered neural circuit models have arisen because they can recapitulate the structural and functional characteristics of in vivo neural circuits. These in vitro neural circuits allow the mimicking of dysregulation of the neural circuits, including neurodegenerative diseases and traumatic brain injury. Emerging in vitro engineered neural circuits will provide a better understanding of the (patho-)physiology of neural circuits.
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Affiliation(s)
- Seokyoung Bang
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea
| | - Kyeong Seob Hwang
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea; School of Mechanical Engineering, Yonsei University, Seoul 03722, Republic of Korea
| | - Sohyeon Jeong
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea; Division of Bio-Medical Science & Technology, KIST School, Korea University of Science and Technology (UST), Seoul 02792, Republic of Korea
| | - Il-Joo Cho
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea; Division of Bio-Medical Science & Technology, KIST School, Korea University of Science and Technology (UST), Seoul 02792, Republic of Korea; School of Electrical and Electronics Engineering, Yonsei University, Seoul 03722, Republic of Korea; Yonsei-KIST Convergence Research Institute, Yonsei University, Seoul 03722, Republic of Korea
| | - Nakwon Choi
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea; Division of Bio-Medical Science & Technology, KIST School, Korea University of Science and Technology (UST), Seoul 02792, Republic of Korea; KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 02841, Republic of Korea.
| | - Jongbaeg Kim
- School of Mechanical Engineering, Yonsei University, Seoul 03722, Republic of Korea.
| | - Hong Nam Kim
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea; Division of Bio-Medical Science & Technology, KIST School, Korea University of Science and Technology (UST), Seoul 02792, Republic of Korea.
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7
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Yang L, Pijuan-Galito S, Rho HS, Vasilevich AS, Eren AD, Ge L, Habibović P, Alexander MR, de Boer J, Carlier A, van Rijn P, Zhou Q. High-Throughput Methods in the Discovery and Study of Biomaterials and Materiobiology. Chem Rev 2021; 121:4561-4677. [PMID: 33705116 PMCID: PMC8154331 DOI: 10.1021/acs.chemrev.0c00752] [Citation(s) in RCA: 64] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Indexed: 02/07/2023]
Abstract
The complex interaction of cells with biomaterials (i.e., materiobiology) plays an increasingly pivotal role in the development of novel implants, biomedical devices, and tissue engineering scaffolds to treat diseases, aid in the restoration of bodily functions, construct healthy tissues, or regenerate diseased ones. However, the conventional approaches are incapable of screening the huge amount of potential material parameter combinations to identify the optimal cell responses and involve a combination of serendipity and many series of trial-and-error experiments. For advanced tissue engineering and regenerative medicine, highly efficient and complex bioanalysis platforms are expected to explore the complex interaction of cells with biomaterials using combinatorial approaches that offer desired complex microenvironments during healing, development, and homeostasis. In this review, we first introduce materiobiology and its high-throughput screening (HTS). Then we present an in-depth of the recent progress of 2D/3D HTS platforms (i.e., gradient and microarray) in the principle, preparation, screening for materiobiology, and combination with other advanced technologies. The Compendium for Biomaterial Transcriptomics and high content imaging, computational simulations, and their translation toward commercial and clinical uses are highlighted. In the final section, current challenges and future perspectives are discussed. High-throughput experimentation within the field of materiobiology enables the elucidation of the relationships between biomaterial properties and biological behavior and thereby serves as a potential tool for accelerating the development of high-performance biomaterials.
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Affiliation(s)
- Liangliang Yang
- University
of Groningen, W. J. Kolff Institute for Biomedical Engineering and
Materials Science, Department of Biomedical Engineering, University Medical Center Groningen, A. Deusinglaan 1, 9713 AV Groningen, The Netherlands
| | - Sara Pijuan-Galito
- School
of Pharmacy, Biodiscovery Institute, University
of Nottingham, University Park, Nottingham NG7 2RD, U.K.
| | - Hoon Suk Rho
- Department
of Instructive Biomaterials Engineering, MERLN Institute for Technology-Inspired
Regenerative Medicine, Maastricht University, 6229 ER Maastricht, The Netherlands
| | - Aliaksei S. Vasilevich
- Department
of Biomedical Engineering, Eindhoven University
of Technology, 5600 MB Eindhoven, The Netherlands
| | - Aysegul Dede Eren
- Department
of Biomedical Engineering, Eindhoven University
of Technology, 5600 MB Eindhoven, The Netherlands
| | - Lu Ge
- University
of Groningen, W. J. Kolff Institute for Biomedical Engineering and
Materials Science, Department of Biomedical Engineering, University Medical Center Groningen, A. Deusinglaan 1, 9713 AV Groningen, The Netherlands
| | - Pamela Habibović
- Department
of Instructive Biomaterials Engineering, MERLN Institute for Technology-Inspired
Regenerative Medicine, Maastricht University, 6229 ER Maastricht, The Netherlands
| | - Morgan R. Alexander
- School
of Pharmacy, Boots Science Building, University
of Nottingham, University Park, Nottingham NG7 2RD, U.K.
| | - Jan de Boer
- Department
of Biomedical Engineering, Eindhoven University
of Technology, 5600 MB Eindhoven, The Netherlands
| | - Aurélie Carlier
- Department
of Cell Biology-Inspired Tissue Engineering, MERLN Institute for Technology-Inspired
Regenerative Medicine, Maastricht University, 6229 ER Maastricht, The Netherlands
| | - Patrick van Rijn
- University
of Groningen, W. J. Kolff Institute for Biomedical Engineering and
Materials Science, Department of Biomedical Engineering, University Medical Center Groningen, A. Deusinglaan 1, 9713 AV Groningen, The Netherlands
| | - Qihui Zhou
- Institute
for Translational Medicine, Department of Stomatology, The Affiliated
Hospital of Qingdao University, Qingdao
University, Qingdao 266003, China
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8
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Aghlmandi A, Nikshad A, Safaralizadeh R, Warkiani ME, Aghebati-Maleki L, Yousefi M. Microfluidics as efficient technology for the isolation and characterization of stem cells. EXCLI JOURNAL 2021; 20:426-443. [PMID: 33746671 PMCID: PMC7975637 DOI: 10.17179/excli2020-3028] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 02/15/2021] [Indexed: 01/09/2023]
Abstract
The recent years have been passed with significant progressions in the utilization of microfluidic technologies for cellular investigations. The aim of microfluidics is to mimic small-scale body environment with features like optical transparency. Microfluidics can screen and monitor different cell types during culture and study cell function in response to stimuli in a fully controlled environment. No matter how the microfluidic environment is similar to in vivo environment, it is not possible to fully investigate stem cells behavior in response to stimuli during cell proliferation and differentiation. Researchers have used stem cells in different fields from fundamental researches to clinical applications. Many cells in the body possess particular functions, but stem cells do not have a specific task and can turn into almost any type of cells. Stem cells are undifferentiated cells with the ability of changing into specific cells that can be essential for the body. Researchers and physicians are interested in stem cells to use them in testing the function of the body's systems and solving their complications. This review discusses the recent advances in utilizing microfluidic techniques for the analysis of stem cells, and mentions the advantages and disadvantages of using microfluidic technology for stem cell research.
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Affiliation(s)
- Afsoon Aghlmandi
- Department of Animal Biology, Faculty of Natural Science, University of Tabriz, Tabriz, Iran
| | - Aylin Nikshad
- Department of Animal Biology, Faculty of Natural Science, University of Tabriz, Tabriz, Iran
| | - Reza Safaralizadeh
- Department of Animal Biology, Faculty of Natural Science, University of Tabriz, Tabriz, Iran
| | - Majid Ebrahimi Warkiani
- The School of Biomedical Engineering, University of Technology Sydney, Sydney, NSW, Australia
| | | | - Mehdi Yousefi
- Stem Cell Research Center, Tabriz University of Medical Science, Tabriz, Iran
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9
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Rapid Fabrication of Membrane-Integrated Thermoplastic Elastomer Microfluidic Devices. MICROMACHINES 2020; 11:mi11080731. [PMID: 32731570 PMCID: PMC7463978 DOI: 10.3390/mi11080731] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 07/19/2020] [Accepted: 07/25/2020] [Indexed: 02/06/2023]
Abstract
Leveraging the advantageous material properties of recently developed soft thermoplastic elastomer materials, this work presents the facile and rapid fabrication of composite membrane-integrated microfluidic devices consisting of FlexdymTM polymer and commercially available porous polycarbonate membranes. The three-layer devices can be fabricated in under 2.5 h, consisting of a 2-min hot embossing cycle, conformal contact between device layers and a low-temperature baking step. The strength of the FlexdymTM-polycarbonate seal was characterized using a specialized microfluidic delamination device and an automated pressure controller configuration, offering a standardized and high-throughput method of microfluidic burst testing. Given a minimum bonding distance of 200 μm, the materials showed bonding that reliably withstood pressures of 500 mbar and above, which is sufficient for most microfluidic cell culture applications. Bonding was also stable when subjected to long term pressurization (10 h) and repeated use (10,000 pressure cycles). Cell culture trials confirmed good cell adhesion and sustained culture of human dermal fibroblasts on a polycarbonate membrane inside the device channels over the course of one week. In comparison to existing porous membrane-based microfluidic platforms of this configuration, most often made of polydimethylsiloxane (PDMS), these devices offer a streamlined fabrication methodology with materials having favourable properties for cell culture applications and the potential for implementation in barrier model organ-on-chips.
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10
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Fabrication of Hollow Structures in Photodegradable Hydrogels Using a Multi-Photon Excitation Process for Blood Vessel Tissue Engineering. MICROMACHINES 2020; 11:mi11070679. [PMID: 32668567 PMCID: PMC7408076 DOI: 10.3390/mi11070679] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 07/09/2020] [Accepted: 07/09/2020] [Indexed: 01/06/2023]
Abstract
Engineered blood vessels generally recapitulate vascular function in vitro and can be utilized in drug discovery as a novel microphysiological system. Recently, various methods to fabricate vascular models in hydrogels have been reported to study the blood vessel functions in vitro; however, in general, it is difficult to fabricate hollow structures with a designed size and structure with a tens of micrometers scale for blood vessel tissue engineering. This study reports a method to fabricate the hollow structures in photodegradable hydrogels prepared in a microfluidic device. An infrared femtosecond pulsed laser, employed to induce photodegradation via multi-photon excitation, was scanned in the hydrogel in a program-controlled manner for fabricating the designed hollow structures. The photodegradable hydrogel was prepared by a crosslinking reaction between an azide-modified gelatin solution and a dibenzocyclooctyl-terminated photocleavable tetra-arm polyethylene glycol crosslinker solution. After assessing the composition of the photodegradable hydrogel in terms of swelling and cell adhesion, the hydrogel prepared in the microfluidic device was processed by laser scanning to fabricate linear and branched hollow structures present in it. We introduced a microsphere suspension into the fabricated structure in photodegradable hydrogels, and confirmed the fabrication of perfusable hollow structures of designed patterns via the multi-photon excitation process.
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11
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Hiraiwa T, Yamada TG, Miki N, Funahashi A, Hiroi N. Activation of cell migration via morphological changes in focal adhesions depends on shear stress in MYCN-amplified neuroblastoma cells. J R Soc Interface 2020; 16:20180934. [PMID: 30836897 PMCID: PMC6451396 DOI: 10.1098/rsif.2018.0934] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Neuroblastoma is the most common solid tumour of childhood, and it metastasizes to distant organs. However, the mechanism of metastasis, which generally depends on the cell motility of the neuroblastoma, remains unclear. In many solid tumours, it has been reported that shear stress promotes metastasis. Here, we investigated the relationship between shear stress and cell motility in the MYCN-amplified human neuroblastoma cell line IMR32, using a microfluidic device. We confirmed that most of the cells migrated downstream, and cell motility increased dramatically when the cells were exposed to a shear stress of 0.4 Pa, equivalent to that expected in vivo. We observed that the morphological features of focal adhesion were changed under a shear stress of 0.4 Pa. We also investigated the relationship between malignancy and the motility of IMR32 cells under shear stress. Decreasing the expression of MYCN in IMR32 cells via siRNA transfection inhibited cell motility by a shear stress of 0.4 Pa. These results suggest that MYCN-amplified neuroblastoma cells under high shear stress migrate to distant organs due to high cell motility, allowing cell migration to lymphatic vessels and venules.
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Affiliation(s)
- Takumi Hiraiwa
- 1 Department of Biosciences and Informatics, Keio University , Kanagawa , Japan
| | - Takahiro G Yamada
- 1 Department of Biosciences and Informatics, Keio University , Kanagawa , Japan
| | - Norihisa Miki
- 2 Department of Mechanical Engineering, Keio University , Kanagawa , Japan
| | - Akira Funahashi
- 1 Department of Biosciences and Informatics, Keio University , Kanagawa , Japan
| | - Noriko Hiroi
- 3 Department of Pharmacy, Sanyo-Onoda City University , Yamaguchi , Japan
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12
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Glass NR, Takasako M, Er PX, Titmarsh DM, Hidalgo A, Wolvetang EJ, Little MH, Cooper-White JJ. Multivariate patterning of human pluripotent cells under perfusion reveals critical roles of induced paracrine factors in kidney organoid development. SCIENCE ADVANCES 2020; 6:eaaw2746. [PMID: 31934619 PMCID: PMC6949035 DOI: 10.1126/sciadv.aaw2746] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Accepted: 10/30/2019] [Indexed: 06/10/2023]
Abstract
Creating complex multicellular kidney organoids from pluripotent stem cells shows great promise. Further improvements in differentiation outcomes, patterning, and maturation of specific cell types are, however, intrinsically limited by standard tissue culture approaches. We describe a novel full factorial microbioreactor array-based methodology to achieve rapid interrogation and optimization of this complex multicellular differentiation process in a facile manner. We successfully recapitulate early kidney tissue patterning events, exploring more than 1000 unique conditions in an unbiased and quantitative manner, and define new media combinations that achieve near-pure renal cell type specification. Single-cell resolution identification of distinct renal cell types within multilayered kidney organoids, coupled with multivariate analysis, defined the definitive roles of Wnt, fibroblast growth factor, and bone morphogenetic protein signaling in their specification, exposed retinoic acid as a minimal effector of nephron patterning, and highlighted critical contributions of induced paracrine factors on cell specification and patterning.
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Affiliation(s)
- Nick R. Glass
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St. Lucia, QLD 4072, Australia
| | - Minoru Takasako
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia 4072, Australia
- Murdoch Children’s Research Institute, Flemington Rd., Parkville, VIC 3052, Australia
| | - Pei Xuan Er
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia 4072, Australia
- Murdoch Children’s Research Institute, Flemington Rd., Parkville, VIC 3052, Australia
| | - Drew M. Titmarsh
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St. Lucia, QLD 4072, Australia
| | - Alejandro Hidalgo
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St. Lucia, QLD 4072, Australia
| | - Ernst J. Wolvetang
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St. Lucia, QLD 4072, Australia
- UQ Centre in Stem Cell and Regenerative Engineering, The University of Queensland, St. Lucia, QLD 4072, Australia
| | - Melissa H. Little
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia 4072, Australia
- Murdoch Children’s Research Institute, Flemington Rd., Parkville, VIC 3052, Australia
- Department of Pediatrics, University of Melbourne, Parkville, VIC 3052, Australia
| | - Justin J. Cooper-White
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St. Lucia, QLD 4072, Australia
- UQ Centre in Stem Cell and Regenerative Engineering, The University of Queensland, St. Lucia, QLD 4072, Australia
- Biomedical Manufacturing, Manufacturing Flagship, CSIRO, Clayton, VIC 3169, Australia
- School of Chemical Engineering, The University of Queensland, St. Lucia, QLD 4072, Australia
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13
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da Silva Morais A, Oliveira JM, Reis RL. Biomaterials and Microfluidics for Liver Models. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1230:65-86. [DOI: 10.1007/978-3-030-36588-2_5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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14
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An S, Han SY, Cho SW. Hydrogel-integrated Microfluidic Systems for Advanced Stem Cell Engineering. BIOCHIP JOURNAL 2019. [DOI: 10.1007/s13206-019-3402-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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15
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DiSalvo M, Smiddy NM, Allbritton NL. Automated sensing and splitting of stem cell colonies on microraft arrays. APL Bioeng 2019; 3:036106. [PMID: 31489396 PMCID: PMC6715441 DOI: 10.1063/1.5113719] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 08/17/2019] [Indexed: 01/24/2023] Open
Abstract
Human induced pluripotent stem cells (hiPSCs) are widely used for disease modeling, tissue engineering, and clinical applications. Although the development of new disease-relevant or customized hiPSC lines is of high importance, current automated hiPSC isolation technologies rely largely on the fluorescent labeling of cells, thus limiting the cell line development from many applications. The objective of this research was to develop a platform for high-throughput hiPSC cytometry and splitting that utilized a label-free cell sensing approach. An image analysis pipeline utilizing background subtraction and standard deviation projections was implemented to detect hiPSC colonies from bright-field microscopy data. The pipeline was incorporated into an automated microscopy system coupling quad microraft cell-isolation arrays, computer-based vision, and algorithms for smart decision making and cell sorting. The pipeline exhibited a hiPSC detection specificity of 98% and a sensitivity of 88%, allowing for the successful tracking of growth for hundreds of microcolonies over 7 days. The automated platform split 170 mother colonies from a microarray within 80 min, and the harvested daughter biopsies were expanded into viable hiPSC colonies suitable for downstream assays, such as polymerase chain reaction (PCR) or continued culture. Transmitted light microscopy offers an alternative, label-free modality for isolating hiPSCs, yet its low contrast and specificity for adherent cells remain a challenge for automation. This novel approach to label-free sensing and microcolony subsampling with the preservation of the mother colony holds the potential for hiPSC colony screening based on a wide range of properties including those measurable only by a cell destructive assay.
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Affiliation(s)
- Matthew DiSalvo
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, Chapel Hill/Raleigh, North Carolina 27599/27607, USA
| | - Nicole M. Smiddy
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
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16
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Laing AF, Tirumala V, Hegarty E, Mondal S, Zhao P, Hamilton WB, Brickman JM, Ben-Yakar A. An automated microfluidic device for time-lapse imaging of mouse embryonic stem cells. BIOMICROFLUIDICS 2019; 13:054102. [PMID: 31558920 PMCID: PMC6748857 DOI: 10.1063/1.5124057] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2019] [Accepted: 08/20/2019] [Indexed: 06/10/2023]
Abstract
Long-term, time-lapse imaging studies of embryonic stem cells (ESCs) require a controlled and stable culturing environment for high-resolution imaging. Microfluidics is well-suited for such studies, especially when the media composition needs to be rapidly and accurately altered without disrupting the imaging. Current studies in plates, which can only add molecules at the start of an experiment without any information on the levels of endogenous signaling before the exposure, are incompatible with continuous high-resolution imaging and cell-tracking. Here, we present a custom designed, fully automated microfluidic chip to overcome these challenges. A unique feature of our chip includes three-dimensional ports that can connect completely sealed on-chip valves for fluid control to individually addressable cell culture chambers with thin glass bottoms for high-resolution imaging. We developed a robust protocol for on-chip culturing of mouse ESCs for minimum of 3 days, to carry out experiments reliably and repeatedly. The on-chip ESC growth rate was similar to that on standard culture plates with same initial cell density. We tested the chips for high-resolution, time-lapse imaging of a sensitive reporter of ESC lineage priming, Nanog-GFP, and HHex-Venus with an H2B-mCherry nuclear marker for cell-tracking. Two color imaging of cells was possible over a 24-hr period while maintaining cell viability. Importantly, changing the media did not affect our ability to track individual cells. This system now enables long-term fluorescence imaging studies in a reliable and automated manner in a fully controlled microenvironment.
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Affiliation(s)
- Adam F. Laing
- Department of Mechanical Engineering, The University of Texas at Austin, 204 E. Dean Keeton St., Austin, Texas 78712, USA
| | - Venkat Tirumala
- Department of Chemical Engineering, The University of Texas at Austin, 200 E. Dean Keeton St., Austin, Texas 78712, USA
| | - Evan Hegarty
- Department of Mechanical Engineering, The University of Texas at Austin, 204 E. Dean Keeton St., Austin, Texas 78712, USA
| | - Sudip Mondal
- Department of Mechanical Engineering, The University of Texas at Austin, 204 E. Dean Keeton St., Austin, Texas 78712, USA
| | - Peisen Zhao
- Department of Electrical and Computer Engineering, The University of Texas at Austin, 2501 Speedway, Austin, Texas 78712, USA
| | - William B. Hamilton
- The Novo Nordisk Foundation Center for Stem Cell Biology—DanStem, University of Copenhagen, 3B Blegdamsvej, DK-2200 Copenhagen N, Denmark
| | - Joshua M. Brickman
- The Novo Nordisk Foundation Center for Stem Cell Biology—DanStem, University of Copenhagen, 3B Blegdamsvej, DK-2200 Copenhagen N, Denmark
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17
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Microfluidic models of physiological or pathological flow shear stress for cell biology, disease modeling and drug development. Trends Analyt Chem 2019. [DOI: 10.1016/j.trac.2019.06.023] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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18
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Shen Y, Du K, Zou L, Zhou X, Lv R, Gao D, Qiu B, Ding W. Rapid and continuous on-chip loading of trehalose into erythrocytes. Biomed Microdevices 2019; 21:5. [PMID: 30607639 DOI: 10.1007/s10544-018-0352-y] [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] [Indexed: 11/26/2022]
Abstract
Freeze-drying is a promising approach for the long-term storage of erythrocytes at room temperature. Studies have shown that trehalose loaded into erythrocytes plays an important role in protecting erythrocytes against freeze-drying damage. Due to the impermeability of the erythrocyte membrane to trehalose, many methods have been developed to load trehalose into erythrocytes. However, these methods usually require multistep manual manipulation and long processing time; the adopted protocols are also diverse and not standardized. Thus, we develop an osmotically-based trehalose-loading microdevice (TLM) to rapidly, continuously, and automatically produce erythrocytes with loaded trehalose. In the TLM, trehalose is loaded through the erythrocyte membrane pores induced by hypotonic shock; then, the trehalose-loaded erythrocytes are rinsed to remove hemoglobin molecules and cell fragments, and the extracellular solution is restored to the isotonic state by integrating a rinsing-recovering design. First, the mixing function and the rinsing-recovering function were confirmed using a fluorescent solution. Then, the performance of the TLM was evaluated under various operating conditions with respect to the loading efficiency of trehalose, the hemolysis rate of erythrocytes (ϕ), the recovery rate of hemoglobin in erythrocytes (φ), and the separation efficiency of the TLM. Finally, the preliminary study of the freeze-drying of erythrocytes with loaded trehalose was accomplished using the TLM. The results showed that under the designated operating conditions, the loading efficiency for human erythrocytes reached ~21 mM in ~2 min with a ϕ value of ~17% and a φ value of ~74%. This study provides insights into the design of the on-chip loading of trehalose into erythrocytes and promotes the automation of life science studies on biochips.
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Affiliation(s)
- Yiren Shen
- Center for Biomedical Engineering, University of Science and Technology of China, Hefei, 230027, Anhui, China
- Department of Electronic Science and Technology, University of Science and Technology of China, Hefei, 230027, Anhui, China
| | - Kun Du
- Center for Biomedical Engineering, University of Science and Technology of China, Hefei, 230027, Anhui, China
- Department of Electronic Science and Technology, University of Science and Technology of China, Hefei, 230027, Anhui, China
| | - Lili Zou
- Center for Biomedical Engineering, University of Science and Technology of China, Hefei, 230027, Anhui, China
- Department of Electronic Science and Technology, University of Science and Technology of China, Hefei, 230027, Anhui, China
| | - Xiaoming Zhou
- School of Mechatronics Engineering, University of Electronic Science and Technology of China, Chengdu, 610054, Sichuan, China
| | - Rong Lv
- Hefei Blood Center, Hefei, 230000, Anhui, China
| | - Dayong Gao
- Department of Mechanical Engineering, University of Washington, Seattle, WA, 98195, USA
| | - Bensheng Qiu
- Center for Biomedical Engineering, University of Science and Technology of China, Hefei, 230027, Anhui, China
- Department of Electronic Science and Technology, University of Science and Technology of China, Hefei, 230027, Anhui, China
| | - Weiping Ding
- Center for Biomedical Engineering, University of Science and Technology of China, Hefei, 230027, Anhui, China.
- Department of Electronic Science and Technology, University of Science and Technology of China, Hefei, 230027, Anhui, China.
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19
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Wang L, Li Z, Xu C, Qin J. Bioinspired Engineering of Organ-on-Chip Devices. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1174:401-440. [PMID: 31713207 DOI: 10.1007/978-981-13-9791-2_13] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The human body can be viewed as an organism consisting of a variety of cellular and non-cellular materials interacting in a highly ordered manner. Its complex and hierarchical nature inspires the multi-level recapitulation of the human body in order to gain insights into the inner workings of life. While traditional cell culture models have led to new insights into the cellular microenvironment and biological control in vivo, deeper understanding of biological systems and human pathophysiology requires the development of novel model systems that allow for analysis of complex internal and external interactions within the cellular microenvironment in a more relevant organ context. Engineering organ-on-chip systems offers an unprecedented opportunity to unravel the complex and hierarchical nature of human organs. In this chapter, we first highlight the advances in microfluidic platforms that enable engineering of the cellular microenvironment and the transition from cells-on-chips to organs-on-chips. Then, we introduce the key features of the emerging organs-on-chips and their proof-of-concept applications in biomedical research. We also discuss the challenges and future outlooks of this state-of-the-art technology.
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Affiliation(s)
- Li Wang
- Division of Biotechnology, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, P. R. China
| | - Zhongyu Li
- Division of Biotechnology, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, P. R. China
| | - Cong Xu
- Division of Biotechnology, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, P. R. China
| | - Jianhua Qin
- Division of Biotechnology, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, P. R. China. .,CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, China. .,Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, China. .,University of Chinese Academy of Sciences, Beijing, China.
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20
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Duru LN, Quan Z, Qazi TJ, Qing H. Stem cells technology: a powerful tool behind new brain treatments. Drug Deliv Transl Res 2018; 8:1564-1591. [PMID: 29916013 DOI: 10.1007/s13346-018-0548-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Stem cell research has recently become a hot research topic in biomedical research due to the foreseen unlimited potential of stem cells in tissue engineering and regenerative medicine. For many years, medicine has been facing intense challenges, such as an insufficient number of organ donations that is preventing clinicians to fulfill the increasing needs. To try and overcome this regrettable matter, research has been aiming at developing strategies to facilitate the in vitro culture and study of stem cells as a tool for tissue regeneration. Meanwhile, new developments in the microfluidics technology brought forward emerging cell culture applications that are currently allowing for a better chemical and physical control of cellular microenvironment. This review presents the latest developments in stem cell research that brought new therapies to the clinics and how the convergence of the microfluidics technology with stem cell research can have positive outcomes on the fields of regenerative medicine and high-throughput screening. These advances will bring new translational solutions for drug discovery and will upgrade in vitro cell culture to a new level of accuracy and performance. We hope this review will provide new insights into the understanding of new brain treatments from the perspective of stem cell technology especially regarding regenerative medicine and tissue engineering.
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Affiliation(s)
- Lucienne N Duru
- School of Life Science, Beijing Institute of Technology, Beijing, China
| | - Zhenzhen Quan
- School of Life Science, Beijing Institute of Technology, Beijing, China
| | - Talal Jamil Qazi
- School of Life Science, Beijing Institute of Technology, Beijing, China
| | - Hong Qing
- School of Life Science, Beijing Institute of Technology, Beijing, China. .,Beijing Key Laboratory of Separation and Analysis in Biomedical and Pharmaceuticals, Department of Biomedical Engineering, School of Life Science, Beijing Institute of Technology, 5 South Zhongguancun Street, Haidian District, Beijing, 100081, China.
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21
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Abstract
Microfluidics has played a vital role in developing novel methods to investigate biological phenomena at the molecular and cellular level during the last two decades. Microscale engineering of cellular systems is nevertheless a nascent field marked inherently by frequent disruptive advancements in technology such as PDMS-based soft lithography. Viable culture and manipulation of cells in microfluidic devices requires knowledge across multiple disciplines including molecular and cellular biology, chemistry, physics, and engineering. There has been numerous excellent reviews in the past 15 years on applications of microfluidics for molecular and cellular biology including microfluidic cell culture (Berthier et al., 2012; El-Ali, Sorger, & Jensen, 2006; Halldorsson et al., 2015; Kim et al., 2007; Mehling & Tay, 2014; Sackmann et al., 2014; Whitesides, 2006; Young & Beebe, 2010), cell culture models (Gupta et al., 2016; Inamdar & Borenstein, 2011; Meyvantsson & Beebe, 2008), cell secretion (Schrell et al., 2016), chemotaxis (Kim & Wu, 2012; Wu et al., 2013), neuron culture (Millet & Gillette, 2012a, 2012b), drug screening (Dittrich & Manz, 2006; Eribol, Uguz, & Ulgen, 2016; Wu, Huang, & Lee, 2010), cell sorting (Autebert et al., 2012; Bhagat et al., 2010; Gossett et al., 2010; Wyatt Shields Iv, Reyes, & López, 2015), single cell studies (Lecault et al., 2012; Reece et al., 2016; Yin & Marshall, 2012), stem cell biology (Burdick & Vunjak-Novakovic, 2009; Wu et al., 2011; Zhang & Austin, 2012), cell differentiation (Zhang et al., 2017a), systems biology (Breslauer, Lee, & Lee, 2006), 3D cell culture (Huh et al., 2011; Li et al., 2012; van Duinen et al., 2015), spheroids and organoids (Lee et al., 2016; Montanez-Sauri, Beebe, & Sung, 2015; Morimoto & Takeuchi, 2013; Skardal et al., 2016; Young, 2013), organ-on-chip (Bhatia & Ingber, 2014; Esch, Bahinski, & Huh, 2015; Huh et al., 2011; van der Meer & van den Berg, 2012), and tissue engineering (Andersson & Van Den Berg, 2004; Choi et al., 2007; Hasan et al., 2014). In this chapter, we provide an overview of PDMS-based microdevices for microfluidic cell culture. We discuss the advantages and challenges of using PDMS-based soft lithography for microfluidic cell culture and highlight recent progress and future directions in this area.
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Affiliation(s)
- Melikhan Tanyeri
- Biomedical Engineering Program, Duquesne University, Pittsburgh, PA, United States
| | - Savaş Tay
- Institute of Molecular Engineering, University of Chicago, Chicago, IL, United States; Institute of Genomics and Systems Biology, University of Chicago, Chicago, IL, United States.
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22
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Varma S, Voldman J. Caring for cells in microsystems: principles and practices of cell-safe device design and operation. LAB ON A CHIP 2018; 18:3333-3352. [PMID: 30324208 PMCID: PMC6254237 DOI: 10.1039/c8lc00746b] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Microfluidic device designers and users continually question whether cells are 'happy' in a given microsystem or whether they are perturbed by micro-scale technologies. This issue is normally brought up by engineers building platforms, or by external reviewers (academic or commercial) comparing multiple technological approaches to a problem. Microsystems can apply combinations of biophysical and biochemical stimuli that, although essential to device operation, may damage cells in complex ways. However, assays to assess the impact of microsystems upon cells have been challenging to conduct and have led to subjective interpretation and evaluation of cell stressors, hampering development and adoption of microsystems. To this end, we introduce a framework that defines cell health, describes how device stimuli may stress cells, and contrasts approaches to measure cell stress. Importantly, we provide practical guidelines regarding device design and operation to minimize cell stress, and recommend a minimal set of quantitative assays that will enable standardization in the assessment of cell health in diverse devices. We anticipate that as microsystem designers, reviewers, and end-users enforce such guidelines, we as a community can create a set of essential principles that will further the adoption of such technologies in clinical, translational and commercial applications.
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Affiliation(s)
- Sarvesh Varma
- Department of Electrical Engineering and Computer Science
, Massachusetts Institute of Technology
,
77 Massachusetts Avenue, Room 36-824
, Cambridge
, USA
.
; Fax: +617 258 5846
; Tel: +617 253 1583
| | - Joel Voldman
- Department of Electrical Engineering and Computer Science
, Massachusetts Institute of Technology
,
77 Massachusetts Avenue, Room 36-824
, Cambridge
, USA
.
; Fax: +617 258 5846
; Tel: +617 253 1583
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23
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Acevedo JP, Angelopoulos I, van Noort D, Khoury M. Microtechnology applied to stem cells research and development. Regen Med 2018; 13:233-248. [PMID: 29557299 DOI: 10.2217/rme-2017-0123] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Microfabrication and microfluidics contribute to the research of cellular functions of cells and their interaction with their environment. Previously, it has been shown that microfluidics can contribute to the isolation, selection, characterization and migration of cells. This review aims to provide stem cell researchers with a toolkit of microtechnology (mT) instruments for elucidating complex stem cells functions which are challenging to decipher with traditional assays and animal models. These microdevices are able to investigate about the differentiation and niche interaction, stem cells transcriptomics, therapeutic functions and the capture of their secreted microvesicles. In conclusion, microtechnology will allow a more realistic assessment of stem cells properties, driving and accelerating the translation of regenerative medicine approaches to the clinic.
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Affiliation(s)
- Juan Pablo Acevedo
- Laboratory of Nano-Regenerative Medicine, Faculty of Medicine, Universidad de Los Andes, Santiago, Chile.,Cells for Cells, Santiago, Chile
| | - Ioannis Angelopoulos
- Laboratory of Nano-Regenerative Medicine, Faculty of Medicine, Universidad de Los Andes, Santiago, Chile.,Cells for Cells, Santiago, Chile
| | - Danny van Noort
- Facultad de Ingeniería y Ciencias Aplicadas Universidad de los Andes, Santiago, Chile.,Biotechnology, IFM, Linköping University, Sweden
| | - Maroun Khoury
- Laboratory of Nano-Regenerative Medicine, Faculty of Medicine, Universidad de Los Andes, Santiago, Chile.,Cells for Cells, Santiago, Chile.,Consorcio Regenero, Santiago, Chile
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24
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Geraili A, Jafari P, Hassani MS, Araghi BH, Mohammadi MH, Ghafari AM, Tamrin SH, Modarres HP, Kolahchi AR, Ahadian S, Sanati-Nezhad A. Controlling Differentiation of Stem Cells for Developing Personalized Organ-on-Chip Platforms. Adv Healthc Mater 2018; 7. [PMID: 28910516 DOI: 10.1002/adhm.201700426] [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] [Received: 04/02/2017] [Revised: 06/01/2017] [Indexed: 01/09/2023]
Abstract
Organ-on-chip (OOC) platforms have attracted attentions of pharmaceutical companies as powerful tools for screening of existing drugs and development of new drug candidates. OOCs have primarily used human cell lines or primary cells to develop biomimetic tissue models. However, the ability of human stem cells in unlimited self-renewal and differentiation into multiple lineages has made them attractive for OOCs. The microfluidic technology has enabled precise control of stem cell differentiation using soluble factors, biophysical cues, and electromagnetic signals. This study discusses different tissue- and organ-on-chip platforms (i.e., skin, brain, blood-brain barrier, bone marrow, heart, liver, lung, tumor, and vascular), with an emphasis on the critical role of stem cells in the synthesis of complex tissues. This study further recaps the design, fabrication, high-throughput performance, and improved functionality of stem-cell-based OOCs, technical challenges, obstacles against implementing their potential applications, and future perspectives related to different experimental platforms.
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Affiliation(s)
- Armin Geraili
- Department of Chemical and Petroleum Engineering; Sharif University of Technology; Azadi, Tehran 14588-89694 Iran
- Graduate Program in Biomedical Engineering; Western University; London N6A 5B9 ON Canada
| | - Parya Jafari
- Graduate Program in Biomedical Engineering; Western University; London N6A 5B9 ON Canada
- Department of Electrical Engineering; Sharif University of Technology; Azadi, Tehran 14588-89694 Iran
| | - Mohsen Sheikh Hassani
- Department of Systems and Computer Engineering; Carleton University; 1125 Colonel By Drive Ottawa K1S 5B6 ON Canada
| | - Behnaz Heidary Araghi
- Department of Materials Science and Engineering; Sharif University of Technology; Azadi, Tehran 14588-89694 Iran
| | - Mohammad Hossein Mohammadi
- Institute of Biomaterials and Biomedical Engineering; University of Toronto; Toronto ON M5S 3G9 Canada
- Department of Chemical Engineering and Applied Chemistry; University of Toronto; Toronto Ontario M5S 3E5 Canada
| | - Amir Mohammad Ghafari
- Department of Stem Cells and Developmental Biology; Cell Science Research Center; Royan Institute for Stem Cell Biology and Technology; Tehran 16635-148 Iran
| | - Sara Hasanpour Tamrin
- BioMEMS and Bioinspired Microfluidic Laboratory (BioM); Department of Mechanical and Manufacturing Engineering; University of Calgary; 2500 University Drive N.W. Calgary T2N 1N4 AB Canada
| | - Hassan Pezeshgi Modarres
- BioMEMS and Bioinspired Microfluidic Laboratory (BioM); Department of Mechanical and Manufacturing Engineering; University of Calgary; 2500 University Drive N.W. Calgary T2N 1N4 AB Canada
| | - Ahmad Rezaei Kolahchi
- BioMEMS and Bioinspired Microfluidic Laboratory (BioM); Department of Mechanical and Manufacturing Engineering; University of Calgary; 2500 University Drive N.W. Calgary T2N 1N4 AB Canada
| | - Samad Ahadian
- Institute of Biomaterials and Biomedical Engineering; University of Toronto; Toronto ON M5S 3G9 Canada
- Department of Chemical Engineering and Applied Chemistry; University of Toronto; Toronto Ontario M5S 3E5 Canada
| | - Amir Sanati-Nezhad
- BioMEMS and Bioinspired Microfluidic Laboratory (BioM); Department of Mechanical and Manufacturing Engineering; University of Calgary; 2500 University Drive N.W. Calgary T2N 1N4 AB Canada
- Center for Bioengineering Research and Education; Biomedical Engineering Program; University of Calgary; Calgary T2N 1N4 AB Canada
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McKee C, Chaudhry GR. Advances and challenges in stem cell culture. Colloids Surf B Biointerfaces 2017; 159:62-77. [PMID: 28780462 DOI: 10.1016/j.colsurfb.2017.07.051] [Citation(s) in RCA: 184] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Revised: 07/04/2017] [Accepted: 07/22/2017] [Indexed: 12/12/2022]
Abstract
Stem cells (SCs) hold great promise for cell therapy, tissue engineering, and regenerative medicine as well as pharmaceutical and biotechnological applications. They have the capacity to self-renew and the ability to differentiate into specialized cell types depending upon their source of isolation. However, use of SCs for clinical applications requires a high quality and quantity of cells. This necessitates large-scale expansion of SCs followed by efficient and homogeneous differentiation into functional derivatives. Traditional methods for maintenance and expansion of cells rely on two-dimensional (2-D) culturing techniques using plastic culture plates and xenogenic media. These methods provide limited expansion and cells tend to lose clonal and differentiation capacity upon long-term passaging. Recently, new approaches for the expansion of SCs have emphasized three-dimensional (3-D) cell growth to mimic the in vivo environment. This review provides a comprehensive compendium of recent advancements in culturing SCs using 2-D and 3-D techniques involving spheroids, biomaterials, and bioreactors. In addition, potential challenges to achieve billion-fold expansion of cells are discussed.
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Affiliation(s)
- Christina McKee
- Department of Biological Sciences , Oakland University, Rochester, MI, 48309, USA; OU-WB Institute for Stem Cell and Regenerative Medicine, Oakland University, Rochester, MI, 48309, USA
| | - G Rasul Chaudhry
- Department of Biological Sciences , Oakland University, Rochester, MI, 48309, USA; OU-WB Institute for Stem Cell and Regenerative Medicine, Oakland University, Rochester, MI, 48309, USA.
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26
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Zou L, Li S, Kang Y, Liu J, He L, Sun S, Gao D, Qiu B, Ding W. A multistage-dialysis microdevice for extraction of cryoprotectants. Biomed Microdevices 2017; 19:30. [DOI: 10.1007/s10544-017-0174-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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27
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Varma S, Fendyur A, Box A, Voldman J. Multiplexed Cell-Based Sensors for Assessing the Impact of Engineered Systems and Methods on Cell Health. Anal Chem 2017; 89:4663-4670. [DOI: 10.1021/acs.analchem.7b00256] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
| | | | - Andrew Box
- Cytometry
Shared Resource Laboratory, Stowers Institute for Medical Research, Kansas
City, Missouri 64110, United States
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28
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29
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Advances in Micro- and Nanotechnologies for Stem Cell-Based Translational Applications. STEM CELL BIOLOGY AND REGENERATIVE MEDICINE 2017. [DOI: 10.1007/978-3-319-29149-9_13] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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30
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Super A, Jaccard N, Cardoso Marques MP, Macown RJ, Griffin LD, Veraitch FS, Szita N. Real-time monitoring of specific oxygen uptake rates of embryonic stem cells in a microfluidic cell culture device. Biotechnol J 2016; 11:1179-89. [PMID: 27214658 PMCID: PMC5103178 DOI: 10.1002/biot.201500479] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2015] [Revised: 02/15/2016] [Accepted: 05/12/2016] [Indexed: 01/07/2023]
Abstract
Oxygen plays a key role in stem cell biology as a signaling molecule and as an indicator of cell energy metabolism. Quantification of cellular oxygen kinetics, i.e. the determination of specific oxygen uptake rates (sOURs), is routinely used to understand metabolic shifts. However current methods to determine sOUR in adherent cell cultures rely on cell sampling, which impacts on cellular phenotype. We present real‐time monitoring of cell growth from phase contrast microscopy images, and of respiration using optical sensors for dissolved oxygen. Time‐course data for bulk and peri‐cellular oxygen concentrations obtained for Chinese hamster ovary (CHO) and mouse embryonic stem cell (mESCs) cultures successfully demonstrated this non‐invasive and label‐free approach. Additionally, we confirmed non‐invasive detection of cellular responses to rapidly changing culture conditions by exposing the cells to mitochondrial inhibiting and uncoupling agents. For the CHO and mESCs, sOUR values between 8 and 60 amol cell−1 s−1, and 5 and 35 amol cell−1 s−1 were obtained, respectively. These values compare favorably with literature data. The capability to monitor oxygen tensions, cell growth, and sOUR, of adherent stem cell cultures, non‐invasively and in real time, will be of significant benefit for future studies in stem cell biology and stem cell‐based therapies.
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Affiliation(s)
- Alexandre Super
- Department of Biochemical Engineering, University College London, London, United Kingdom
| | - Nicolas Jaccard
- Department of Biochemical Engineering, University College London, London, United Kingdom.,Centre for Mathematics and Physics in the Life Sciences and Experimental Biology, University College London, London, United Kingdom.,Department of Computer Science, University College London, London, United Kingdom
| | | | - Rhys Jarred Macown
- Department of Biochemical Engineering, University College London, London, United Kingdom
| | - Lewis Donald Griffin
- Department of Computer Science, University College London, London, United Kingdom
| | - Farlan Singh Veraitch
- Department of Biochemical Engineering, University College London, London, United Kingdom
| | - Nicolas Szita
- Department of Biochemical Engineering, University College London, London, United Kingdom.
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31
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Jackson EL, Lu H. Three-dimensional models for studying development and disease: moving on from organisms to organs-on-a-chip and organoids. Integr Biol (Camb) 2016; 8:672-83. [PMID: 27156572 PMCID: PMC4905804 DOI: 10.1039/c6ib00039h] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Human development and disease are challenging to study because of lack of experimental accessibility to in vivo systems and the complex nature of biological processes. For these reasons researchers turn to the use of model systems, ranging in complexity and scale from single cells to model organisms. While the use of model organisms is valuable for studying physiology and pathophysiology in an in vivo context and for aiding pre-clinical development of therapeutics, animal models are costly, difficult to interrogate, and not always equivalent to human biology. For these reasons, three-dimensional (3D) cell cultures have emerged as an attractive model system that contains key aspects of in vivo tissue and organ complexity while being more experimentally tractable than model organisms. In particular, organ-on-a-chip and organoid models represent orthogonal approaches that have been able to recapitulate characteristics of physiology and disease. Here, we review advances in these two categories of 3D cultures and applications in studying development and disease. Additionally, we discuss development of key technologies that facilitate the generation of 3D cultures, including microfluidics, biomaterials, genome editing, and imaging technologies.
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Affiliation(s)
- E L Jackson
- School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA.
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32
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Induction of Human iPSC-Derived Cardiomyocyte Proliferation Revealed by Combinatorial Screening in High Density Microbioreactor Arrays. Sci Rep 2016; 6:24637. [PMID: 27097795 PMCID: PMC4838928 DOI: 10.1038/srep24637] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Accepted: 03/29/2016] [Indexed: 01/25/2023] Open
Abstract
Inducing cardiomyocyte proliferation in post-mitotic adult heart tissue is attracting significant attention as a therapeutic strategy to regenerate the heart after injury. Model animal screens have identified several candidate signalling pathways, however, it remains unclear as to what extent these pathways can be exploited, either individually or in combination, in the human system. The advent of human cardiac cells from directed differentiation of human pluripotent stem cells (hPSCs) now provides the ability to interrogate human cardiac biology in vitro, but it remains difficult with existing culture formats to simply and rapidly elucidate signalling pathway penetrance and interplay. To facilitate high-throughput combinatorial screening of candidate biologicals or factors driving relevant molecular pathways, we developed a high-density microbioreactor array (HDMA) – a microfluidic cell culture array containing 8100 culture chambers. We used HDMAs to combinatorially screen Wnt, Hedgehog, IGF and FGF pathway agonists. The Wnt activator CHIR99021 was identified as the most potent molecular inducer of human cardiomyocyte proliferation, inducing cell cycle activity marked by Ki67, and an increase in cardiomyocyte numbers compared to controls. The combination of human cardiomyocytes with the HDMA provides a versatile and rapid tool for stratifying combinations of factors for heart regeneration.
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33
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Ahn K, Kim SH, Lee GH, Lee S, Heo YS, Park JY. Features of Microsystems for Cultivation and Characterization of Stem Cells with the Aim of Regenerative Therapy. Stem Cells Int 2016; 2016:6023132. [PMID: 26941802 PMCID: PMC4752999 DOI: 10.1155/2016/6023132] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Revised: 11/13/2015] [Accepted: 12/01/2015] [Indexed: 01/17/2023] Open
Abstract
Stem cells have infinite potential for regenerative therapy thanks to their advantageous ability which is differentiable to requisite cell types for recovery and self-renewal. The microsystem has been proved to be more helpful to stem cell studies compared to the traditional methods, relying on its advantageous feature of mimicking in vivo cellular environments as well as other profitable features such as minimum sample consumption for analysis and multiprocedures. A wide variety of microsystems were developed for stem cell studies; however, regenerative therapy-targeted applications of microtechnology should be more emphasized and gain more attractions since the regenerative therapy is one of ultimate goals of biologists and bioengineers. In this review, we introduce stem cell researches harnessing well-known microtechniques (microwell, micropattern, and microfluidic channel) in view point of physical principles and how these systems and principles have been implemented appropriately for characterizing stem cells and finding possible regenerative therapies. Biologists may gain information on the principles of microsystems to apply them to find solutions for their current challenges, and engineers may understand limitations of the conventional microsystems and find new chances for further developing practical microsystems. Through the well combination of engineers and biologists, the regenerative therapy-targeted stem cell researches harnessing microtechnology will find better suitable treatments for human disorders.
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Affiliation(s)
- Kihoon Ahn
- School of Mechanical Engineering, College of Engineering, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Sung-Hwan Kim
- School of Mechanical Engineering, College of Engineering, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Gi-Hun Lee
- School of Mechanical Engineering, College of Engineering, Chung-Ang University, Seoul 06974, Republic of Korea
| | - SeungJin Lee
- School of Mechanical Engineering, College of Engineering, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Yun Seok Heo
- Department of Biomedical Engineering, School of Medicine, Keimyung University, Daegu 42601, Republic of Korea
| | - Joong Yull Park
- School of Mechanical Engineering, College of Engineering, Chung-Ang University, Seoul 06974, Republic of Korea
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35
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Sikorski DJ, Caron NJ, VanInsberghe M, Zahn H, Eaves CJ, Piret JM, Hansen CL. Clonal analysis of individual human embryonic stem cell differentiation patterns in microfluidic cultures. Biotechnol J 2015; 10:1546-54. [PMID: 26059045 DOI: 10.1002/biot.201500035] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Revised: 04/04/2015] [Accepted: 06/05/2015] [Indexed: 01/23/2023]
Abstract
Heterogeneity in the clonal outputs of individual human embryonic stem cells (hESCs) confounds analysis of their properties in studies of bulk populations and how to manipulate them for clinical applications. To circumvent this problem we developed a microfluidic device that supports the robust generation of colonies derived from single ESCs. This microfluidic system contains 160 individually addressable chambers equipped for perfusion culture of individual hESCs that could be shown to match the growth rates, marker expression and colony morphologies obtained in conventional cultures. Use of this microfluidic device to analyze the clonal growth kinetics of multiple individual hESCs induced to differentiation revealed variable shifts in the growth rate, area per cell and expression of OCT4 in the progeny of individual hESCs. Interestingly, low OCT4 expression, a slower growth rate and low nuclear to cytoplasmic ratios were found to be correlated responses. This study demonstrates how microfluidic systems can be used to enable large scale live-cell imaging of isolated hESCs exposed to changing culture conditions, to examine how different aspects of their variable responses are correlated.
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Affiliation(s)
- Darek J Sikorski
- Centre for High-Throughput Biology, University of British Columbia, Vancouver, BC, Canada.,Department of Chemical and Biological Engineering, University of British Columbia, Vancouver, BC, Canada.,Michael Smith Laboratories, University of British Columbia, Vancouver, BC, Canada
| | - Nicolas J Caron
- Michael Smith Laboratories, University of British Columbia, Vancouver, BC, Canada
| | - Michael VanInsberghe
- Centre for High-Throughput Biology, University of British Columbia, Vancouver, BC, Canada
| | - Hans Zahn
- Centre for High-Throughput Biology, University of British Columbia, Vancouver, BC, Canada
| | - Connie J Eaves
- Terry Fox Laboratory, British Columbia Cancer Agency, Vancouver, BC, Canada.,Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada
| | - James M Piret
- Department of Chemical and Biological Engineering, University of British Columbia, Vancouver, BC, Canada.,Michael Smith Laboratories, University of British Columbia, Vancouver, BC, Canada
| | - Carl L Hansen
- Centre for High-Throughput Biology, University of British Columbia, Vancouver, BC, Canada. .,Department of Physics and Astronomy, University of British Columbia, Vancouver, BC, Canada.
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36
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Varma S, Voldman J. A cell-based sensor of fluid shear stress for microfluidics. LAB ON A CHIP 2015; 15:1563-73. [PMID: 25648195 PMCID: PMC4443851 DOI: 10.1039/c4lc01369g] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Microsystems designed for cell-based studies or applications inherently require fluid handling. Flows within such systems inevitably generate fluid shear stress (FSS) that may adversely affect cell health. Simple assays of cell viability, morphology or growth are typically reported to indicate any gross disturbances to cell physiology. However, no straightforward metric exists to specifically evaluate physiological implications of FSS within microfluidic devices, or among competing microfluidic technologies. This paper presents the first genetically encoded cell sensors that fluoresce in a quantitative fashion upon FSS pathway activation. We picked a widely used cell line (NIH3T3s) and created a transcriptional cell-sensor where fluorescence turns on when transcription of a relevant FSS-induced protein is initiated. Specifically, we chose Early Growth Factor-1 (a mechanosensitive protein) upregulation as the node for FSS detection. We verified our sensor pathway specificity and functionality by noting induced fluorescence in response to chemical induction of the FSS pathway, seen both through microscopy and flow cytometry. Importantly, we found our cell sensors to be inducible by a range of FSS intensities and durations, with a limit of detection of 2 dynes cm(-2) when applied for 30 minutes. Additionally, our cell-sensors proved their versatility by showing induction sensitivity when made to flow through an inertial microfluidic device environment with typical flow conditions. We anticipate these cell sensors to have wide application in the microsystems community, allowing the device designer to engineer systems with acceptable FSS, and enabling the end-user to evaluate the impact of FSS upon their assay of interest.
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Affiliation(s)
- Sarvesh Varma
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Room 36-824, Cambridge, USA.
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37
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Tao FF, Xiao X, Lei KF, Lee IC. Paper-based cell culture microfluidic system. BIOCHIP JOURNAL 2015. [DOI: 10.1007/s13206-015-9202-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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38
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39
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Prabhakaran MP, Vatankhah E, Kai D, Ramakrishna S. Methods for Nano/Micropatterning of Substrates: Toward Stem Cells Differentiation. INT J POLYM MATER PO 2014. [DOI: 10.1080/00914037.2014.945207] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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40
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Esteve V, Berganzo J, Monge R, Martínez-Bisbal MC, Villa R, Celda B, Fernandez L. Development of a three-dimensional cell culture system based on microfluidics for nuclear magnetic resonance and optical monitoring. BIOMICROFLUIDICS 2014; 8:064105. [PMID: 25553182 PMCID: PMC4240776 DOI: 10.1063/1.4902002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Accepted: 11/04/2014] [Indexed: 06/02/2023]
Abstract
A new microfluidic cell culture device compatible with real-time nuclear magnetic resonance (NMR) is presented here. The intended application is the long-term monitoring of 3D cell cultures by several techniques. The system has been designed to fit inside commercially available NMR equipment to obtain maximum readout resolution when working with small samples. Moreover, the microfluidic device integrates a fibre-optic-based sensor to monitor parameters such as oxygen, pH, or temperature during NMR monitoring, and it also allows the use of optical microscopy techniques such as confocal fluorescence microscopy. This manuscript reports the initial trials culturing neurospheres inside the microchamber of this device and the preliminary images and spatially localised spectra obtained by NMR. The images show the presence of a necrotic area in the interior of the neurospheres, as is frequently observed in histological preparations; this phenomenon appears whenever the distance between the cells and fresh nutrients impairs the diffusion of oxygen. Moreover, the spectra acquired in a volume of 8 nl inside the neurosphere show an accumulation of lactate and lipids, which are indicative of anoxic conditions. Additionally, a basis for general temperature control and monitoring and a graphical control software have been developed and are also described. The complete platform will allow biomedical assays of therapeutic agents to be performed in the early phases of therapeutic development. Thus, small quantities of drugs or advanced nanodevices may be studied long-term under simulated living conditions that mimic the flow and distribution of nutrients.
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41
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Matsumura T, Tatsumi K, Noda Y, Nakanishi N, Okonogi A, Hirano K, Li L, Osumi T, Tada T, Kotera H. Single-cell cloning and expansion of human induced pluripotent stem cells by a microfluidic culture device. Biochem Biophys Res Commun 2014; 453:131-7. [PMID: 25264198 DOI: 10.1016/j.bbrc.2014.09.081] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Accepted: 09/18/2014] [Indexed: 01/09/2023]
Abstract
The microenvironment of cells, which includes basement proteins, shear stress, and extracellular stimuli, should be taken into consideration when examining physiological cell behavior. Although microfluidic devices allow cellular responses to be analyzed with ease at the single-cell level, few have been designed to recover cells. We herein demonstrated that a newly developed microfluidic device helped to improve culture conditions and establish a clonality-validated human pluripotent stem cell line after tracing its growth at the single-cell level. The device will be a helpful tool for capturing various cell types in the human body that have not yet been established in vitro.
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Affiliation(s)
- Taku Matsumura
- Research and Development Division, ARKRAY, Inc., Kyoto 602-0008, Japan
| | - Kazuya Tatsumi
- Mechanical Engineering and Science, Faculty of Engineering, Kyoto University, Yoshida Honmachi, Sakyo-ku, Kyoto 606-8501, Japan
| | - Yuichiro Noda
- Research and Development Division, ARKRAY, Inc., Kyoto 602-0008, Japan
| | - Naoyuki Nakanishi
- Research and Development Division, ARKRAY, Inc., Kyoto 602-0008, Japan
| | - Atsuhito Okonogi
- Research and Development Division, ARKRAY, Inc., Kyoto 602-0008, Japan
| | - Kunio Hirano
- Research and Development Division, ARKRAY, Inc., Kyoto 602-0008, Japan.
| | - Liu Li
- Institute for Integrated Cell-Material Sciences (WPI-iCeMS), Kyoto University, Kyoto, Japan
| | - Takashi Osumi
- Research and Development Division, ARKRAY, Inc., Kyoto 602-0008, Japan
| | - Takashi Tada
- Stem Cell Engineering, Institute for Frontier Medical Sciences, Kyoto University, 53 Kawahara-cho, Shogo-in, Sakyo-ku, Kyoto 606-8507, Japan
| | - Hidetoshi Kotera
- Micro Engineering, Faculty of Engineering, Kyoto University, Yoshida Honmachi, Sakyo-ku, Kyoto 606-8501, Japan.
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42
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Zhang X, Huk DJ, Wang Q, Lincoln J, Zhao Y. A microfluidic shear device that accommodates parallel high and low stress zones within the same culturing chamber. BIOMICROFLUIDICS 2014; 8:054106. [PMID: 25332743 PMCID: PMC4189595 DOI: 10.1063/1.4894783] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Accepted: 08/26/2014] [Indexed: 05/02/2023]
Abstract
Fluid shear stress (FSS) plays a critical role in regulating endothelium function and maintaining vascular homeostasis. Current microfluidic devices for studying FSS effects on cells either separate high shear stress zone and low shear stress zone into different culturing chambers, or arranging the zones serially along the flow direction, which complicates subsequent data interpretation. In this paper, we report a diamond shaped microfluidic shear device where the high shear stress zone and the low shear stress zone are arranged in parallel within one culturing chamber. Since the zones with different shear stress magnitudes are aligned normal to the flow direction, the cells in one stress group are not substantially affected by the flow-induced cytokine/chemokine releases by cells in the other group. Cell loading experiments using human umbilical vein endothelial cells show that the device is able to reveal stress magnitude-dependent and loading duration-dependent cell responses. The co-existence of shear stress zones with varied magnitudes within the same culturing chamber not only ensures that all the cells are subject to the identical culturing conditions, but also allows the resemblance of the differential shear stress pattern in natural arterial conditions. The device is expected to provide a new solution for studying the effects of heterogeneous hemodynamic patterns in the onset and progression of various vascular diseases.
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Affiliation(s)
- X Zhang
- Laboratory for Biomedical Microsystems, Department of Biomedical Engineering, The Ohio State University , Columbus, Ohio 43210, USA
| | - D J Huk
- The Heart Center and Nationwide Children's Hospital Research Institute , Columbus, Ohio 43205, USA
| | - Q Wang
- Laboratory for Biomedical Microsystems, Department of Biomedical Engineering, The Ohio State University , Columbus, Ohio 43210, USA
| | | | - Y Zhao
- Laboratory for Biomedical Microsystems, Department of Biomedical Engineering, The Ohio State University , Columbus, Ohio 43210, USA
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43
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Abstract
Microfluidic perfusion culture is a novel technique to culture animal cells in a small-scale microchamber with medium perfusion. Polydimethylsiloxane (PDMS) is the most popular material to fabricate a microfluidic perfusion culture chip. Photolithography and replica molding techniques are generally used for fabrication of a microfluidic perfusion culture chip. Pressure-driven perfusion culture system is convenient technique to carry out the perfusion culture of animal cells in a microfluidic device. Here, we describe a general theory on microfluid network design, microfabrication technique, and experimental technique for pressure-driven perfusion culture in an 8 × 8 microchamber array on a glass slide-sized microchip made out of PDMS.
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Affiliation(s)
- Koji Hattori
- Research Center for Stem Cell Engineering, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki, Japan
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44
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Rutledge K, Jabbarzadeh E. Nanoengineered Platforms to Guide Pluripotent Stem Cell Fate. JOURNAL OF NANOMEDICINE & NANOTECHNOLOGY 2014; 5:217. [PMID: 26918198 PMCID: PMC4764045 DOI: 10.4172/2157-7439.1000217] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Tissue engineering utilizes cells, signaling molecules, and scaffolds towards creating functional tissue to repair damaged organs. Pluripotent stem cells (PSCs) are a promising cell source due to their ability to self-renewal indefinitely and their potential to differentiate into almost any cell type. Great strides have been taken to parse the physiological mechanisms by which PSCs respond to their microenvironment and commit to a specific lineage. The combination of physical cues and chemical factors is thought to have the most profound influence on stem cell behavior, therefore a major focus of tissue engineering strategies is scaffold design to incorporate these signals. One overlooked component of the in vivo microenvironment researchers attempt to recapitulate with three dimensional (3D) substrates is the nanoarchitecture formed by the fibrillar network of extracellular matrix (ECM) proteins. These nanoscale features have the ability to impact cell adhesion, migration, proliferation, and lineage commitment. Significant advances have been made in deciphering how these nanoscale cues interact with stem cells to determine phenotype, but much is still unknown as to how the interplay between physical and chemical signals regulate in vitro and in vivo cellular fate. This review dives deeper to investigate nanoscale platforms for engineering tissue, as well use the use of these nanotechnologies to drive pluripotent stem cell lineage determination.
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Affiliation(s)
- Katy Rutledge
- Department of Chemical Engineering, University of South Carolina, Columbia, SC, 29208, USA
| | - Ehsan Jabbarzadeh
- Department of Chemical Engineering, University of South Carolina, Columbia, SC, 29208, USA
- Biomedical Engineering Program, University of South Carolina, Columbia, SC, 29208, USA
- Department of Orthopaedic Surgery, University of South Carolina School of Medicine, Columbia, SC, 29209, USA
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45
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Dereli-Korkut Z, Akaydin HD, Ahmed AHR, Jiang X, Wang S. Three dimensional microfluidic cell arrays for ex vivo drug screening with mimicked vascular flow. Anal Chem 2014; 86:2997-3004. [PMID: 24568664 PMCID: PMC3982971 DOI: 10.1021/ac403899j] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
![]()
Currently, there are no reliable ex vivo models
that predict anticancer drug responses in human tumors accurately.
A comprehensive method of mimicking a 3D microenvironment to study
effects of anticancer drugs on specific cancer types is essential.
Here, we report the development of a three-dimensional microfluidic
cell array (3D μFCA), which reconstructs a 3D tumor microenvironment
with cancer cells and microvascular endothelial cells. To mimic the in vivo spatial relationship between microvessels and nonendothelial
cells embedded in extracellular matrix, three polydimethylsiloxane
(PDMS) layers were built into this array. The multilayer property
of the device enabled the imitation of the drug delivery in a microtissue
array with simulated blood circulation. This 3D μFCA system
may provide better predictions of drug responses and identification
of a suitable treatment for a specific patient if biopsy samples are
used. To the pharmaceutical industry, the scaling-up of our 3D μFCA
system may offer a novel high throughput screening tool.
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Affiliation(s)
- Zeynep Dereli-Korkut
- Department of Biomedical Engineering, The City College of the City University of New York , 160 Convent Ave. Steinman Hall T-434, New York, New York 10031, United States
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46
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Satoh T, Sugiura S, Sumaru K, Ozaki S, Gomi S, Kurakazu T, Oshima Y, Kanamori T. Inverting microwell array chip for the cultivation of human induced pluripotent stem cells with controlled aggregate size and geometrical arrangement. BIOMICROFLUIDICS 2014; 8:024112. [PMID: 24803961 PMCID: PMC4000399 DOI: 10.1063/1.4871036] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Accepted: 03/31/2014] [Indexed: 05/25/2023]
Abstract
We present a novel cell culture chip, namely, "inverting microwell array chip," for cultivation of human induced pluripotent stem cells. The chip comprises a lower hydrogel microwell array and an upper polystyrene culture surface. We demonstrate the formation of uniform cellular aggregates in the microwell array, and after inversion, a culture with controlled aggregate size and geometrical arrangement on the polystyrene surface. Here, we report effects of cell concentrations on a cultivation sequence in the chip.
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Affiliation(s)
- Taku Satoh
- Research Center for Stem Cell Engineering, National Institute of Advanced Industrial Science and Technology (AIST), AIST Tsukuba Central 5, 1-1-1, Higashi, Tsukuba, Ibaraki 305-8568, Japan
| | - Shinji Sugiura
- Research Center for Stem Cell Engineering, National Institute of Advanced Industrial Science and Technology (AIST), AIST Tsukuba Central 5, 1-1-1, Higashi, Tsukuba, Ibaraki 305-8568, Japan
| | - Kimio Sumaru
- Research Center for Stem Cell Engineering, National Institute of Advanced Industrial Science and Technology (AIST), AIST Tsukuba Central 5, 1-1-1, Higashi, Tsukuba, Ibaraki 305-8568, Japan
| | - Shigenori Ozaki
- Tokyo Electron Limited, 5-3-1 Akasaka, Minato-ku, Tokyo 107-6325, Japan
| | - Shinichi Gomi
- Tokyo Electron Limited, 5-3-1 Akasaka, Minato-ku, Tokyo 107-6325, Japan
| | - Tomoaki Kurakazu
- Tokyo Electron Limited, 5-3-1 Akasaka, Minato-ku, Tokyo 107-6325, Japan
| | - Yasuhiro Oshima
- Tokyo Electron Limited, 5-3-1 Akasaka, Minato-ku, Tokyo 107-6325, Japan
| | - Toshiyuki Kanamori
- Research Center for Stem Cell Engineering, National Institute of Advanced Industrial Science and Technology (AIST), AIST Tsukuba Central 5, 1-1-1, Higashi, Tsukuba, Ibaraki 305-8568, Japan
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47
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Huang X, Hui W, Hao C, Yue W, Yang M, Cui Y, Wang Z. On-site formation of emulsions by controlled air plugs. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2014; 10:758-765. [PMID: 24030982 DOI: 10.1002/smll.201202659] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2012] [Revised: 07/12/2013] [Indexed: 06/02/2023]
Abstract
Air plugs are usually undesirable in microfluidic systems because of their detrimental effect on the system's stability and integrity. By controlling the wetting properties as well as the topographical geometry of the microchannel, it is reported herein that air plugs can be generated in pre-defined locations to function as a unique valve, allowing for the on-site formation of various emulsions including single-component droplets, composite droplets with droplet-to-droplet concentration gradient, blood droplets, paired droplets, as well as bubble arrays without the need for precious flow control, a difficult task with conventional droplet microfluidics. Moreover, the self-generated air valve can be readily deactivated (turned off) by the introduction of an oil phase, allowing for the on-demand release of as-formed droplets for downstream applications. It is proposed that the simple, yet versatile nature of this technique can act as an important method for droplet microfluidics and, in particular, is ideal for the development of affordable lab-on-a-chip systems without suffering from scalability and manufacturing challenges that typically confound the conventional droplet microfluidics.
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Affiliation(s)
- Xiaowen Huang
- Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Hong Kong, China
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48
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Titmarsh DM, Ovchinnikov DA, Wolvetang EJ, Cooper-White JJ. Full factorial screening of human embryonic stem cell maintenance with multiplexed microbioreactor arrays. Biotechnol J 2014; 8:822-34. [PMID: 23813764 DOI: 10.1002/biot.201200375] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2012] [Revised: 04/09/2013] [Accepted: 06/03/2013] [Indexed: 11/07/2022]
Abstract
Use of human pluripotent stem cells (hPSCs) in regenerative medicine applications relies on control of cell fate decisions by exogenous factors. This control can be hindered by the use of undefined culture components, poorly understood autocrine/paracrine effects, spatiotemporal variations in microenvironmental composition inherent to static culture formats, and signal cross-talk between multiple factors. We recently described microbioreactor arrays that provide a full factorial spectrum of exogenous factors, and allow gradual accumulation of paracrine factors through serial culture chambers. We combined these with defined biochemical conditions, and in situ reporter gene- and immunofluorescence-based readouts to create an hPSC screening platform with enhanced data throughput and microenvironmental control. HES3-EOS-C(3+)-EiP reporter hESCs were screened against FGF-2, TGF-β1, and retinoic acid in a modified mTeSR-1 medium background. Differential pluripotency marker expression reflected mTeSR-1's maintenance capacity, and differentiation in response to removal of maintenance factors or addition of retinoic acid. Interestingly, pluripotency marker expression was downregulated progressively through serial chambers. Since downstream chambers are exposed to greater levels of paracrine factors under continuous flow, this effect is thought to result from secreted factors that negatively influence pluripotency. The microbioreactor array platform decodes factor interplay, and has a broad application in deciphering microenvironmental control of cell fate.
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Affiliation(s)
- Drew M Titmarsh
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St. Lucia, QLD, Australia
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Kinney MA, Hookway TA, Wang Y, McDevitt TC. Engineering three-dimensional stem cell morphogenesis for the development of tissue models and scalable regenerative therapeutics. Ann Biomed Eng 2014; 42:352-67. [PMID: 24297495 PMCID: PMC3939035 DOI: 10.1007/s10439-013-0953-9] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Accepted: 11/21/2013] [Indexed: 12/11/2022]
Abstract
The physiochemical stem cell microenvironment regulates the delicate balance between self-renewal and differentiation. The three-dimensional assembly of stem cells facilitates cellular interactions that promote morphogenesis, analogous to the multicellular, heterotypic tissue organization that accompanies embryogenesis. Therefore, expansion and differentiation of stem cells as multicellular aggregates provides a controlled platform for studying the biological and engineering principles underlying spatiotemporal morphogenesis and tissue patterning. Moreover, three-dimensional stem cell cultures are amenable to translational screening applications and therapies, which underscores the broad utility of scalable suspension cultures across laboratory and clinical scales. In this review, we discuss stem cell morphogenesis in the context of fundamental biophysical principles, including the three-dimensional modulation of adhesions, mechanics, and molecular transport and highlight the opportunities to employ stem cell spheroids for tissue modeling, bioprocessing, and regenerative therapies.
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Affiliation(s)
- Melissa A. Kinney
- The Wallace H. Coulter Department of Biomedical Engineering Georgia Institute of Technology/Emory University, Atlanta, GA, USA
| | - Tracy A. Hookway
- The Wallace H. Coulter Department of Biomedical Engineering Georgia Institute of Technology/Emory University, Atlanta, GA, USA
| | - Yun Wang
- The Wallace H. Coulter Department of Biomedical Engineering Georgia Institute of Technology/Emory University, Atlanta, GA, USA
| | - Todd C. McDevitt
- The Wallace H. Coulter Department of Biomedical Engineering Georgia Institute of Technology/Emory University, Atlanta, GA, USA
- The Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA
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Zhang Y, Shin DJ, Wang TH. Serial dilution via surface energy trap-assisted magnetic droplet manipulation. LAB ON A CHIP 2013; 13:4827-31. [PMID: 24162777 PMCID: PMC3963271 DOI: 10.1039/c3lc50915j] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
This paper demonstrates a facile method of generating precise serial dilutions in the form of droplets on an open surface platform. The method relies on the use of surface energy traps (SETs), etched areas of high surface energy on a Teflon coated glass substrate, to assist in the magnetic manipulation of droplets to meter and dispense liquid of defined volumes for the preparation of serial dilutions. The volume of the dispensed liquid can be precisely controlled by the size of the SETs, facilitating generation of concentration profiles of high linearity. We have applied this approach to the generation of serial dilutions of antibiotics for anti-microbial susceptibility testing (AST).
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Affiliation(s)
- Yi Zhang
- Department of Biomedical Engineering, Johns Hopkins University, 3400 North Charles Street, Clark 122, Baltimore, Maryland, USA.
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