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Han X, Zhang Q, Zhang G, Sun B, Wu L, Li G. Controllable Fabrication of Highly Ordered Spherical Microcavity Arrays by Replica Molding of In Situ Self-Emulsified Droplets. ACS APPLIED MATERIALS & INTERFACES 2024; 16:26886-26898. [PMID: 38717383 DOI: 10.1021/acsami.4c02176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2024]
Abstract
Ordered spherical hollow micro- and nanostructures hold great appeal in the fields of cell biology and optics. However, it is extremely challenging for standard lithography techniques to achieve spherical micro-/nanocavities. In this paper, we describe a simple, cost-effective, and scalable approach to fabricate highly ordered spherical microcavity arrays by replica molding of in situ self-emulsified droplets. The in situ self-emulsion involves a two-step process: discontinuous dewetting-induced liquid partition and interfacial tension-driven liquid spherical transformation. Subsequent replica molding of the droplets creates spherical microcavity arrays. The shapes and sizes of the microcavities can be easily modulated by varying the compositions of the droplet templates or utilizing an osmotically driven water permeation. To demonstrate the utility of this method, we employed it to create a spherical microwell array for the mass production of embryoid bodies with high viability and minimal loss. In addition, we also demonstrated the optical functions of the generated spherical microcavities by using them as microlenses. We believe that our proposed method will open exciting avenues in fields ranging from regenerative medicine and microchemistry to optical applications.
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Affiliation(s)
- Xue Han
- Key Laboratory of Optoelectronic Technology and Systems, Ministry of Education, Defense Key Disciplines Lab of Novel Micro-Nano Devices and System Technology, Chongqing University, Chongqing 400044, China
| | - Qi Zhang
- Key Laboratory of Optoelectronic Technology and Systems, Ministry of Education, Defense Key Disciplines Lab of Novel Micro-Nano Devices and System Technology, Chongqing University, Chongqing 400044, China
| | - Guoyuan Zhang
- State Key Lab of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, China
| | - Bangyong Sun
- School of Future Technology, Xinjiang University, Urumqi 830017, China
| | - Lei Wu
- State Key Lab of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, China
| | - Gang Li
- Key Laboratory of Optoelectronic Technology and Systems, Ministry of Education, Defense Key Disciplines Lab of Novel Micro-Nano Devices and System Technology, Chongqing University, Chongqing 400044, China
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Lee S, Kim N, Kim SH, Um SJ, Park JY. Biological and mechanical influence of three-dimensional microenvironment formed in microwell on multicellular spheroids composed of heterogeneous hair follicle stem cells. Sci Rep 2023; 13:22742. [PMID: 38123607 PMCID: PMC10733424 DOI: 10.1038/s41598-023-49510-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 12/08/2023] [Indexed: 12/23/2023] Open
Abstract
Hair loss caused by malfunction of the hair follicle stem cells (HFSCs) and physical damage to the skin is difficult to recover from naturally. To overcome these obstacles to hair follicle (HF) regeneration, it is essential to understand the three-dimensional (3D) microenvironment and interactions of various cells within the HFs. Therefore, 3D cell culture technology has been used in HF regeneration research; specifically, multicellular spheroids have been generally adapted to mimic the 3D volumetric structure of the HF. In this study, we culture HF-derived cells, which are mainly composed of HFSCs, in the form of 3D spheroids using a microwell array and discuss the effects of the 3D cellular environment on HF morphogenesis by expression measurements of Sonic hedgehog signaling and stem cell markers in the HF spheroids. Additionally, the influences of microwell depth on HF spheroid formation and biological conditions were investigated. The biomolecular diffusion and convective flow in the microwell were predicted using computational fluid dynamics, which allows analysis of the physical stimulations occurring on the spheroid at the micro-scale. Although a simple experimental method using the microwell array was adopted in this study, the results provide fundamental insights into the physiological phenomena of HFs in the 3D microenvironment, and the numerical analysis is expected to shed light on the investigation of the geometric parameters of the microwell system.
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Affiliation(s)
- Seungjin Lee
- Department of Mechanical Engineering, Graduate School, Chung-Ang University, 84 Heukseok-ro, Dongjak-gu, Seoul, 06974, Republic of Korea
| | - Nackhyoung Kim
- Department of Integrative Bioscience and Biotechnology, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul, 05006, Republic of Korea
| | - Sung-Hwan Kim
- Cellsmith Inc., 38 Pungseong-ro, Gangdong-gu, Seoul, 05393, Republic of Korea
| | - Soo-Jong Um
- Department of Integrative Bioscience and Biotechnology, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul, 05006, Republic of Korea.
| | - Joong Yull Park
- Department of Mechanical Engineering, Graduate School, Chung-Ang University, 84 Heukseok-ro, Dongjak-gu, Seoul, 06974, Republic of Korea.
- Department of Intelligent Energy and Industry, Graduate School, Chung-Ang University, Seoul, 06974, Republic of Korea.
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Han X, Zhang Q, He H, Zhao Q, Li G. Reflow-molded deep concave microwell arrays for robust and large-scale production of embryoid bodies. LAB ON A CHIP 2023; 23:4378-4389. [PMID: 37695312 DOI: 10.1039/d3lc00504f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
Embryonic stem cell (ESC)-derived aggregates, called embryoid bodies (EBs), are powerful in vitro models used to study human development and disease. However, the cost-effective and large-scale production of homogeneous EBs still remains a challenge. Here, we report a rapid, straightforward method for fabricating closely arrayed deep concave microwells, enabling the mass production of uniform EBs from single cell suspensions. By simply combining micromilling, caramel replica molding, and thermal reflow, we generate convex micromolds with high aspect ratios and excellent surface smoothness. Benefitting from the nature of reflow, this method can produce rounded bottom polydimethylsiloxane (PDMS) microwells, which are not easily achieved with standard soft lithography techniques but critical to producing spherical EBs. To achieve optimal concave microwells, we investigated the effect of thermal reflow temperature and time on the surface smoothness and roundness of the finished microwells. In addition, to further improve the utility of this method, we also investigated the effect of microwell aspect ratio (AR) on the loss of EBs during medium manipulation. The capability of this deep concave microwell system was validated by rapidly generating a large number of human embryonic stem cell (hESC)-derived EBs and then efficiently differentiating them into a cardiac lineage. The proposed fabrication method and deep concave microwell platform are highly practical, and thus will benefit the mass production of EBs for potential tissue regeneration and cell therapy applications.
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Affiliation(s)
- Xue Han
- Key Laboratory of Optoelectronic Technology and Systems, Ministry of Education, Defense Key Disciplines Lab of Novel Micro-Nano Devices and System Technology, Chongqing University, Chongqing 400044, China.
| | - Qi Zhang
- Key Laboratory of Optoelectronic Technology and Systems, Ministry of Education, Defense Key Disciplines Lab of Novel Micro-Nano Devices and System Technology, Chongqing University, Chongqing 400044, China.
| | - Hui He
- Institute of Neuroscience, Key Laboratory of Primate Neurobiology, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai 200031, China
| | - Qiang Zhao
- Key Laboratory of Optoelectronic Technology and Systems, Ministry of Education, Defense Key Disciplines Lab of Novel Micro-Nano Devices and System Technology, Chongqing University, Chongqing 400044, China.
| | - Gang Li
- Key Laboratory of Optoelectronic Technology and Systems, Ministry of Education, Defense Key Disciplines Lab of Novel Micro-Nano Devices and System Technology, Chongqing University, Chongqing 400044, China.
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Shrestha P, Rotatori S, Madden-Hennessey K, Mohammed C, Yang CH, Urbani J, Pettinelli J, Liu X, Zhao Q. Selective expansion of target cells using the Enrich TROVO platform. Biotechniques 2023; 75:56-64. [PMID: 37551835 PMCID: PMC10476488 DOI: 10.2144/btn-2023-0038] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Accepted: 07/24/2023] [Indexed: 08/09/2023] Open
Abstract
Enriching target cell clones from diverse cell populations is vital for many life science applications. We have developed a novel method to rapidly and efficiently purify specific clonal cell populations from a larger, heterogeneous group using the Enrich TroVo system (Enrich Biosystems Inc., CT, USA). This system takes advantage of microfabrication and optical technologies by utilizing small hydrogel wells to separate desired cell populations and an innovative patching technique to selectively eliminate undesired cells. This method allows the isolation and growth of desired cells with minimal impact on their viability and proliferation. We successfully isolated and expanded clonal cell populations of desired cells using two model cells. Compared with fluorescence-activated cell sorting, Enrich TroVo system offers a promising alternative for isolating of sensitive, adherent cells, that is, patient-derived cells.
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Affiliation(s)
- Prem Shrestha
- Enrich Biosystems Inc., 21 Business Park Drive, Suite 4, Branford, CT 06405, USA
| | - Stephen Rotatori
- Enrich Biosystems Inc., 21 Business Park Drive, Suite 4, Branford, CT 06405, USA
| | | | - Christina Mohammed
- Enrich Biosystems Inc., 21 Business Park Drive, Suite 4, Branford, CT 06405, USA
| | - Chi-han Yang
- Enrich Biosystems Inc., 21 Business Park Drive, Suite 4, Branford, CT 06405, USA
| | - Jordan Urbani
- Enrich Biosystems Inc., 21 Business Park Drive, Suite 4, Branford, CT 06405, USA
| | - Joseph Pettinelli
- Enrich Biosystems Inc., 21 Business Park Drive, Suite 4, Branford, CT 06405, USA
| | - Xueqi Liu
- Enrich Biosystems Inc., 21 Business Park Drive, Suite 4, Branford, CT 06405, USA
| | - Qi Zhao
- Enrich Biosystems Inc., 21 Business Park Drive, Suite 4, Branford, CT 06405, USA
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Tartagni O, Borók A, Mensà E, Bonyár A, Monti B, Hofkens J, Porcelli AM, Zuccheri G. Microstructured soft devices for the growth and analysis of populations of homogenous multicellular tumor spheroids. Cell Mol Life Sci 2023; 80:93. [PMID: 36929461 PMCID: PMC10020259 DOI: 10.1007/s00018-023-04748-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 02/21/2023] [Accepted: 03/03/2023] [Indexed: 03/18/2023]
Abstract
Multicellular tumor spheroids are rapidly emerging as an improved in vitro model with respect to more traditional 2D culturing. Microwell culturing is a simple and accessible method for generating a large number of uniformly sized spheroids, but commercially available systems often do not enable researchers to perform complete culturing and analysis pipelines and the mechanical properties of their culture environment are not commonly matching those of the target tissue. We herein report a simple method to obtain custom-designed self-built microwell arrays made of polydimethylsiloxane or agarose for uniform 3D cell structure generation. Such materials can provide an environment of tunable mechanical flexibility. We developed protocols to culture a variety of cancer and non-cancer cell lines in such devices and to perform molecular and imaging characterizations of the spheroid growth, viability, and response to pharmacological treatments. Hundreds of tumor spheroids grow (in scaffolded or scaffold-free conditions) at homogeneous rates and can be harvested at will. Microscopy imaging can be performed in situ during or at the end of the culture. Fluorescence (confocal) microscopy can be performed after in situ staining while retaining the geographic arrangement of spheroids in the plate wells. This platform can enable statistically robust investigations on cancer biology and screening of drug treatments.
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Affiliation(s)
- Ottavia Tartagni
- Department of Pharmacy and Biotechnology, University of Bologna, Via San Donato, 19/2, 40127, Bologna, Italy
| | - Alexandra Borók
- Department of Electronics Technology, Budapest University of Technology and Economics, Budapest, Hungary
| | - Emanuela Mensà
- Department of Pharmacy and Biotechnology, University of Bologna, Via San Donato, 19/2, 40127, Bologna, Italy
| | - Attila Bonyár
- Department of Electronics Technology, Budapest University of Technology and Economics, Budapest, Hungary
| | - Barbara Monti
- Department of Pharmacy and Biotechnology, University of Bologna, Via San Donato, 19/2, 40127, Bologna, Italy
- Interdepartmental Center for Industrial Research on Health Sciences and Technologies, University of Bologna, Bologna, Italy
| | - Johan Hofkens
- Department of Chemistry, KU Leuven, 3001, Leuven, Belgium
| | - Anna Maria Porcelli
- Department of Pharmacy and Biotechnology, University of Bologna, Via San Donato, 19/2, 40127, Bologna, Italy
- Interdepartmental Center for Industrial Research on Health Sciences and Technologies, University of Bologna, Bologna, Italy
| | - Giampaolo Zuccheri
- Department of Pharmacy and Biotechnology, University of Bologna, Via San Donato, 19/2, 40127, Bologna, Italy.
- Interdepartmental Center for Industrial Research on Health Sciences and Technologies, University of Bologna, Bologna, Italy.
- S3 Center, Institute of Nanoscience, Italian National Research Council, Modena, Italy.
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Guo W, Chen Z, Feng Z, Li H, Zhang M, Zhang H, Cui X. Fabrication of Concave Microwells and Their Applications in Micro-Tissue Engineering: A Review. MICROMACHINES 2022; 13:mi13091555. [PMID: 36144178 PMCID: PMC9505614 DOI: 10.3390/mi13091555] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 09/12/2022] [Accepted: 09/15/2022] [Indexed: 05/27/2023]
Abstract
At present, there is an increasing need to mimic the in vivo micro-environment in the culture of cells and tissues in micro-tissue engineering. Concave microwells are becoming increasingly popular since they can provide a micro-environment that is closer to the in vivo environment compared to traditional microwells, which can facilitate the culture of cells and tissues. Here, we will summarize the fabrication methods of concave microwells, as well as their applications in micro-tissue engineering. The fabrication methods of concave microwells include traditional methods, such as lithography and etching, thermal reflow of photoresist, laser ablation, precision-computerized numerical control (CNC) milling, and emerging technologies, such as surface tension methods, the deformation of soft membranes, 3D printing, the molding of microbeads, air bubbles, and frozen droplets. The fabrication of concave microwells is transferring from professional microfabrication labs to common biochemical labs to facilitate their applications and provide convenience for users. Concave microwells have mostly been used in organ-on-a-chip models, including the formation and culture of 3D cell aggregates (spheroids, organoids, and embryoids). Researchers have also used microwells to study the influence of substrate topology on cellular behaviors. We will briefly review their applications in different aspects of micro-tissue engineering and discuss the further applications of concave microwells. We believe that building multiorgan-on-a-chip by 3D cell aggregates of different cell lines will be a popular application of concave microwells, while integrating physiologically relevant molecular analyses with the 3D culture platform will be another popular application in the near future. Furthermore, 3D cell aggregates from these biosystems will find more applications in drug screening and xenogeneic implantation.
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Affiliation(s)
- Weijin Guo
- Department of Biomedical Engineering, Shantou University, Shantou 515063, China
| | - Zejingqiu Chen
- Department of Biology, Shantou University, Shantou 515063, China
| | - Zitao Feng
- Department of Biomedical Engineering, Shantou University, Shantou 515063, China
| | - Haonan Li
- Department of Electrical Engineering, Shantou University, Shantou 515063, China
| | - Muyang Zhang
- Department of Electrical Engineering, Shantou University, Shantou 515063, China
| | - Huiru Zhang
- Guangdong Foshan Lianchuang Graduate School of Engineering, Foshan 528311, China
| | - Xin Cui
- Key Laboratory of Biomaterials of Guangdong Higher Education Institutes, Department of Biomedical Engineering, Jinan University, Guangzhou 510632, China
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Feiyue L, Yang L, Zhao J, Yu Q. An evaluation of the inhibition effects of cell migration of Aspirin soaking 360°square-edge intraocular lens in an in vitro lens capsule model. Curr Eye Res 2021; 47:565-572. [PMID: 34935556 DOI: 10.1080/02713683.2021.2012201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
PURPOSE This study performs to evaluate the Hydrophobic and Hydrosmart 360°square-edge intraocular lens drug delivery of Aspirin using an in vitro lens capsular model. METHODS Cell counting kit-8 assay was used to calculate 50% inhibiting concentration values in both SRA01/04 and HLE-B3 cells. Hoechst staining and transwell assay were used to detect cell proliferation and cell migration. The in vitro lens capsule model was established mainly with a special transwell-col and cell climbing sheet, in which an intraocular lens and the TGF-β2 were added. The ultraviolet spectrophotometer was used to measure the drug concentrations released in vitro. Cell-exclusion zone assay was used to detect the cell migration in the in vitro capsular model. RESULTS It shows that cell morphology and distribution of SRA01/04 in the in vitro lens capsular model were closer to those in vivo. The results revealed that there could be significant inhibiting effects on cell migration of the hydrosmart intraocular lens with a sustained drug release in vitro in 7 days, while the hydrophobic intraocular lens drug delivery of Aspirin was mainly performed only from day 1 to day 3. CONCLUSIONS Results showed the developed hydrosmart intraocular lens could release Aspirin continuously in vitro to inhibit the cell migration of lens epithelial cells.
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Affiliation(s)
- Lian Feiyue
- Department of Ophthalmology, The Fourth Affiliated Hospital of China Medical University, Shenyang, China
| | - Li Yang
- Department of Ophthalmology, The Fourth Affiliated Hospital of China Medical University, Shenyang, China
| | - Jiangyue Zhao
- Department of Ophthalmology, The Fourth Affiliated Hospital of China Medical University, Shenyang, China
| | - Qin Yu
- Department of Ophthalmology, The Fourth Affiliated Hospital of China Medical University, Shenyang, China
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de Souza IR, Canavez ADPM, Schuck DC, Gagosian VSC, de Souza IR, Vicari T, da Silva Trindade E, Cestari MM, Lorencini M, Leme DM. Development of 3D cultures of zebrafish liver and embryo cell lines: a comparison of different spheroid formation methods. ECOTOXICOLOGY (LONDON, ENGLAND) 2021; 30:1893-1909. [PMID: 34379241 DOI: 10.1007/s10646-021-02459-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 07/20/2021] [Indexed: 06/13/2023]
Abstract
Fish cell spheroids are promising 3D culture models for vertebrate replacement in ecotoxicology. However, new alternative ecotoxicological methods must be adapted for applications in industry and for regulatory purposes; such methods must be cost-effective, simple to manipulate and provide rapid results. Therefore, we compared the effectiveness of the traditional hanging drop (HD), orbital shaking (OS), and HD combined with OS (HD+OS) methods on the formation of zebrafish cell line spheroids (ZFL and ZEM2S). Time in HD (3-5 days) and different 96-well plates [flat-bottom or ultra-low attachment of round-bottom (ULA-plates)] in OS were evaluated. Easy handling, rapid spheroid formation, uniform-sized spheroids, and circularity were assessed to identify the best spheroid protocol. Traditional HD alone did not result in ZFL spheroid formation, whereas HD (5 days)+OS did. When using the OS, spheroids only formed on the ULA-plate. Both HD+OS and OS were reproducible in size (177.50 ± 2.81 µm and 225.62 ± 19.20 µm, respectively) and circularity (0.83 ± 0.02 and 0.80 ± 0.01, respectively) of ZFL spheroids. Nevertheless, HD+OS required a considerable time to completely form spheroids (10 days) and intensive handling, whereas the OS was fast (5 days of incubation) and simple. OS also yielded reproducible ZEM2S spheroids in 1 day (226.23 ± 0.57 µm diameter and 0.80 ± 0.01 circularity). In conclusion, OS in ULA-plate is an effective and simple spheroid protocol for high-throughput ecotoxicity testing. This study contributes to identify a fast, reproducible, and simple protocol of single piscine spheroid formation in 96-well plates and supports the application of fish 3D model in industry and academia.
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Affiliation(s)
| | | | | | | | | | - Taynah Vicari
- Graduate Program in Genetics, Department of Genetics, Federal University of Paraná (UFPR), Paraná, Brazil
| | | | | | - Marcio Lorencini
- Grupo Boticário, R&D Department, São José dos Pinhais, Paraná, Brazil
| | - Daniela Morais Leme
- Department of Genetics, Federal University of Paraná (UFPR), Paraná, Brazil.
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Sun B, Zhao Y, Wu W, Zhao Q, Li G. A superhydrophobic chip integrated with an array of medium reservoirs for long-term hanging drop spheroid culture. Acta Biomater 2021; 135:234-242. [PMID: 34389482 DOI: 10.1016/j.actbio.2021.08.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 08/04/2021] [Accepted: 08/05/2021] [Indexed: 01/24/2023]
Abstract
Hanging drop (HD) is one of the most popular methods used for forming three-dimensional (3D) cell spheroids. However, conventional hanging drop systems are only applicable for short-term spheroid culture due to their inconvenience in exchanging cell culture media. Here we present a medium-reservoir-integrated superhydrophobic (MRI-SH) chip for long-term HD spheroid cultures. The device consists of two main components: i) a patterned superhydrophobic (SH) surface containing an array of wettable spots which anchor arrays of droplets of cell suspension, and ii) an array of chambers that serve as medium reservoirs, both interconnected via an array of thru-holes. This configuration provides two distinct advantages over conventional HD configurations: i) the high wettability contrast of the SH pattern on the chip leads to the formation and adhesion of nearly spherical hanging droplets on its surface, which minimizes interactions between the liquid and the substrate; ii) the integrated chambers provide large volumes of medium to maintain longer culture durations. Using this device, spheroids of MHCC97H cells were successfully formed, and the cultured spheroids could maintain high viability for up to 30 days and exhibited enhanced spheroid morphology compared to those cultured in the conventional HD systems. STATEMENT OF SIGNIFICANCE: This paper presents a medium-reservoir-integrated superhydrophobic hanging drop (HD) platform for the long-term culture of spheroids with enhanced morphology. By monolithically integrating medium reservoirs and a patterned SH surface into a single device, this HD platform can not only produce high-quality spheroids, but also permit them to sustain high viability for up to 30 days without the need for tedious medium replenishment. We believe that such a platform will be valuable in a wide range of biological or biomedical applications, including tissue engineering, regenerative medicine, and drug discovery.
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Affiliation(s)
- Bangyong Sun
- Key Laboratory of Optoelectronic Technology and Systems, Ministry of Education, Defence Key Disciplines Lab of Novel Micro-Nano Devices and System Technology, Chongqing University, Chongqing 400044, China
| | - Yi Zhao
- Chongqing Key Laboratory of Translational Research for Cancer Metastasis and Individualized Treatment, Chongqing University Cancer Hospital, Chongqing, 400030, China
| | - Weimin Wu
- School of Mechanical and Power Engineering, Chongqing University of Science and Technology, Chongqing 401331, China
| | - Qiang Zhao
- Key Laboratory of Optoelectronic Technology and Systems, Ministry of Education, Defence Key Disciplines Lab of Novel Micro-Nano Devices and System Technology, Chongqing University, Chongqing 400044, China
| | - Gang Li
- Key Laboratory of Optoelectronic Technology and Systems, Ministry of Education, Defence Key Disciplines Lab of Novel Micro-Nano Devices and System Technology, Chongqing University, Chongqing 400044, China.
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Kim D, Lee SJ, Youn J, Hong H, Eom S, Kim DS. A deep and permeable nanofibrous oval-shaped microwell array for the stable formation of viable and functional spheroids. Biofabrication 2021; 13. [PMID: 34030141 DOI: 10.1088/1758-5090/ac044c] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 05/24/2021] [Indexed: 12/26/2022]
Abstract
Despite the potential of a nanofibrous (NF) microwell array as a permeable microwell array to improve the viability and functions of spheroids, thanks to the superior permeability to both gases and solutes, there have still been difficulties regarding the stable formation of spheroids in the NF microwell array due to the low aspect ratio (AR) and the large interspacing between microwells. This study proposes a nanofibrous oval-shaped microwell array, named the NOVA microwell array, with both a high AR and a high well density, enabling us to not only collect cells in the microwell with a high cell seeding efficiency, but also to generate multiple viable and functional spheroids in a uniform and stable manner. To realize a deep NOVA microwell array with a high aspect ratio (AR = 0.9) and a high well density (494 wells cm-2), we developed a matched-mold thermoforming process for the fabrication of both size- and AR-controllable NOVA microwell arrays with various interspacing between microwells while maintaining the porous nature of the NF membrane. The human hepatocellular carcinoma (HepG2) cell spheroids cultured on the deep NOVA microwell array not only had uniform size and shape, with a spheroid circularity of 0.80 ± 0.03 at a cell seeding efficiency of 94.29 ± 9.55%, but also exhibited enhanced viability with a small fraction of dead cells and promoted functionality with increased albumin secretion, compared with the conventional impermeable microwell array. The superior characteristics of the deep NOVA microwell array, i.e. a high AR, a high well density, and a high permeability, pave the way to the production of various viable and functional spheroids and even organoids in a scalable manner.
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Affiliation(s)
- Dohui Kim
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), 77, Cheongam-ro, Nam-gu, Pohang, Gyeongbuk 37673, Republic of Korea
| | - Seong Jin Lee
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), 77, Cheongam-ro, Nam-gu, Pohang, Gyeongbuk 37673, Republic of Korea
| | - Jaeseung Youn
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), 77, Cheongam-ro, Nam-gu, Pohang, Gyeongbuk 37673, Republic of Korea
| | - Hyeonjun Hong
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), 77, Cheongam-ro, Nam-gu, Pohang, Gyeongbuk 37673, Republic of Korea
| | - Seongsu Eom
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), 77, Cheongam-ro, Nam-gu, Pohang, Gyeongbuk 37673, Republic of Korea
| | - Dong Sung Kim
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), 77, Cheongam-ro, Nam-gu, Pohang, Gyeongbuk 37673, Republic of Korea.,Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), 77, Cheongam-ro, Nam-gu, Pohang, Gyeongbuk 37673, Republic of Korea.,Institute for Convergence Research and Education in Advanced Technology, Yonsei University, 50, Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea
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Krishnan MA, Chelvam V. Developing μSpherePlatform Using a Commercial Hairbrush: An Agarose 3D Culture Platform for Deep-Tissue Imaging of Prostate Cancer. ACS APPLIED BIO MATERIALS 2021; 4:4254-4270. [DOI: 10.1021/acsabm.1c00086] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Mena A. Krishnan
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Khandwa Road, Simrol, Indore 453 552, India
| | - Venkatesh Chelvam
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Khandwa Road, Simrol, Indore 453 552, India
- Department of Chemistry, Indian Institute of Technology Indore, Khandwa Road, Simrol, Indore 453 552, India
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Chen C, Rengarajan V, Kjar A, Huang Y. A matrigel-free method to generate matured human cerebral organoids using 3D-Printed microwell arrays. Bioact Mater 2021; 6:1130-1139. [PMID: 33134606 PMCID: PMC7577195 DOI: 10.1016/j.bioactmat.2020.10.003] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 09/05/2020] [Accepted: 10/06/2020] [Indexed: 12/11/2022] Open
Abstract
The current methods of generating human cerebral organoids rely excessively on the use of Matrigel or other external extracellular matrices (ECM) for cell micro-environmental modulation. Matrigel embedding is problematic for long-term culture and clinical applications due to high inconsistency and other limitations. In this study, we developed a novel microwell culture platform based on 3D printing. This platform, without using Matrigel or external signaling molecules (i.e., SMAD and Wnt inhibitors), successfully generated matured human cerebral organoids with robust formation of high-level features (i.e., wrinkling/folding, lumens, neuronal layers). The formation and timing were comparable or superior to the current Matrigel methods, yet with improved consistency. The effect of microwell geometries (curvature and resolution) and coating materials (i.e., mPEG, Lipidure, BSA) was studied, showing that mPEG outperformed all other coating materials, while curved-bottom microwells outperformed flat-bottom ones. In addition, high-resolution printing outperformed low-resolution printing by creating faithful, isotropically-shaped microwells. The trend of these effects was consistent across all developmental characteristics, including EB formation efficiency and sphericity, organoid size, wrinkling index, lumen size and thickness, and neuronal layer thickness. Overall, the microwell device that was mPEG-coated, high-resolution printed, and bottom curved demonstrated the highest efficacy in promoting organoid development. This platform provided a promising strategy for generating uniform and mature human cerebral organoids as an alternative to Matrigel/ECM-embedding methods.
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Affiliation(s)
| | | | - Andrew Kjar
- Department of Biological Engineering, Utah State University, Logan, UT, 84322, USA
| | - Yu Huang
- Department of Biological Engineering, Utah State University, Logan, UT, 84322, USA
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Wu K, Kuo C, Tu T. A Highly Reproducible Micro U-Well Array Plate Facilitating High-Throughput Tumor Spheroid Culture and Drug Assessment. GLOBAL CHALLENGES (HOBOKEN, NJ) 2021; 5:2000056. [PMID: 33552551 PMCID: PMC7857131 DOI: 10.1002/gch2.202000056] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 09/30/2020] [Indexed: 05/05/2023]
Abstract
3D multicellular tumor spheroids (MCTSs) have recently emerged as a landmark for cancer research due to their inherent traits that are physiologically relevant to primary tumor microenvironments. A facile approach-laser-ablated micro U-wells-has been widely adopted in the past decade. However, the differentiation of microwell uniformities and the construction of arrays have all remained elusive. Herein, an improved laser-ablated microwell array technique is proposed that can not only achieve arrayed MCTSs with identical sizes but can also perform high-throughput drug assessments in situ. Three critical laser ablation parameters, including frequency, duty cycle, and pulse number, are investigated to generate microwells flexibly with a range from 170 to 400 μm. The choice of microwells is optimally arranged into an array via precise control of horizontal spacing (d x) and vertical spacing (d y) amenable of cell-loss-free culture during cell seeding. Harvested T24, A549 and Huh-7 MCTSs from the microwell array correspond to approximately 75 to 140 μm in diameter. Anticancer drug screening of cisplatin validated IC50 values in 2D and MCTS conditions are 3.5 versus 9.1 μM (T24), 11.8 versus 277.7 μM (A549) and 33.5 versus 52.8 μM (Huh-7), and the permeability is measured to range from 0.042 to 0.58 μm min-1.
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Affiliation(s)
- Kuang‐Wei Wu
- Department of Biomedical EngineeringNational Cheng Kung UniversityTainan70101Taiwan
| | - Ching‐Te Kuo
- Department of Mechanical and Electro‐Mechanical EngineeringNational Sun Yat‐sen UniversityKaohsiung80400Taiwan
| | - Ting‐Yuan Tu
- Department of Biomedical EngineeringNational Cheng Kung UniversityTainan70101Taiwan
- Medical Device Innovation CenterNational Cheng Kung UniversityTainan70101Taiwan
- International Center for Wound Repair and RegenerationNational Cheng Kung UniversityTainan70101Taiwan
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14
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Kang SM, Kim D, Lee JH, Takayama S, Park JY. Engineered Microsystems for Spheroid and Organoid Studies. Adv Healthc Mater 2021; 10:e2001284. [PMID: 33185040 PMCID: PMC7855453 DOI: 10.1002/adhm.202001284] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 10/01/2020] [Indexed: 01/09/2023]
Abstract
3D in vitro model systems such as spheroids and organoids provide an opportunity to extend the physiological understanding using recapitulated tissues that mimic physiological characteristics of in vivo microenvironments. Unlike 2D systems, 3D in vitro systems can bridge the gap between inadequate 2D cultures and the in vivo environments, providing novel insights on complex physiological mechanisms at various scales of organization, ranging from the cellular, tissue-, to organ-levels. To satisfy the ever-increasing need for highly complex and sophisticated systems, many 3D in vitro models with advanced microengineering techniques have been developed to answer diverse physiological questions. This review summarizes recent advances in engineered microsystems for the development of 3D in vitro model systems. The relationship between the underlying physics behind the microengineering techniques, and their ability to recapitulate distinct 3D cellular structures and functions of diverse types of tissues and organs are highlighted and discussed in detail. A number of 3D in vitro models and their engineering principles are also introduced. Finally, current limitations are summarized, and perspectives for future directions in guiding the development of 3D in vitro model systems using microengineering techniques are provided.
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Affiliation(s)
- Sung-Min Kang
- Department of Green Chemical Engineering, Sangmyung University, Cheonan, Chungnam, 31066, Republic of Korea
| | - Daehan Kim
- Department of Mechanical Engineering, Chung-Ang University, Seoul, 06974, Republic of Korea
| | - Ji-Hoon Lee
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory School of Medicine, Atlanta, GA, 30332, USA
- The Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Shuichi Takayama
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory School of Medicine, Atlanta, GA, 30332, USA
- The Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Joong Yull Park
- Department of Mechanical Engineering, Chung-Ang University, Seoul, 06974, Republic of Korea
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15
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Behroodi E, Latifi H, Bagheri Z, Ermis E, Roshani S, Salehi Moghaddam M. A combined 3D printing/CNC micro-milling method to fabricate a large-scale microfluidic device with the small size 3D architectures: an application for tumor spheroid production. Sci Rep 2020; 10:22171. [PMID: 33335148 PMCID: PMC7747638 DOI: 10.1038/s41598-020-79015-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Accepted: 12/02/2020] [Indexed: 02/06/2023] Open
Abstract
The fabrication of a large-scale microfluidic mold with 3D microstructures for manufacturing of the conical microwell chip using a combined projection micro-stereolithography (PµSL) 3D printing/CNC micro-milling method for tumor spheroid formation is presented. The PµSL technique is known as the most promising method of manufacturing microfluidic chips due to the possibility of creating complex three-dimensional microstructures with high resolution in the range of several micrometers. The purpose of applying the proposed method is to investigate the influence of microwell depths on the formation of tumor spheroids. In the conventional methods, the construction of three-dimensional microstructures and multi-height chips is difficult, time-consuming, and is performed using a multi-step lithography process. Microwell depth is an essential parameter for microwell design since it directly affects the shear stress of the fluid flow and the diffusion of nutrients, respiratory gases, and growth factors. In this study, a chip was made with microwells of different depth varying from 100 to 500 µm. The mold of the microwell section is printed by the lab-made PµSL printer with 6 and 1 µm lateral and vertical resolutions. Other parts of the mold, such as the main chamber and micro-channels, were manufactured using the CNC micro-milling method. Finally, different parts of the master mold were assembled and used for PDMS casting. The proposed technique drastically simplifies the fabrication and rapid prototyping of large-scale microfluidic devices with high-resolution microstructures by combining 3D printing with the CNC micro-milling method.
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Affiliation(s)
- Ebrahim Behroodi
- Laser and Plasma Research Institute, Shahid Beheshti University, 1983963113, Tehran, Iran
| | - Hamid Latifi
- Laser and Plasma Research Institute, Shahid Beheshti University, 1983963113, Tehran, Iran. .,Department of Physics, Shahid Beheshti University, 1983963113, Tehran, Iran.
| | - Zeinab Bagheri
- Faculty of Life Sciences and Biotechnology, Shahid Beheshti University, 1983963113, Tehran, Iran
| | - Esra Ermis
- Faculty of Life Sciences and Biotechnology, Shahid Beheshti University, 1983963113, Tehran, Iran
| | - Shabnam Roshani
- Faculty of Life Sciences and Biotechnology, Shahid Beheshti University, 1983963113, Tehran, Iran
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Li Z, Guo X, Sun L, Xu J, Liu W, Li T, Wang J. A simple microsphere‐based mold to rapidly fabricate microwell arrays for multisize 3D tumor culture. Biotechnol Bioeng 2020; 117:1092-1100. [DOI: 10.1002/bit.27257] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 11/21/2019] [Accepted: 12/15/2019] [Indexed: 12/20/2022]
Affiliation(s)
- Zixiu Li
- College of Chemistry & Pharmacy Northwest A&F University Yangling Shaanxi P. R. China
| | - Xiaofang Guo
- College of Chemistry & Pharmacy Northwest A&F University Yangling Shaanxi P. R. China
| | - Lili Sun
- College of Chemistry & Pharmacy Northwest A&F University Yangling Shaanxi P. R. China
| | - Juan Xu
- College of Chemistry & Pharmacy Northwest A&F University Yangling Shaanxi P. R. China
| | - Wenming Liu
- School of Basic Medical Science Central South University Changsha Hunan P. R. China
| | - Tianbao Li
- College of Chemistry & Pharmacy Northwest A&F University Yangling Shaanxi P. R. China
| | - Jinyi Wang
- College of Chemistry & Pharmacy Northwest A&F University Yangling Shaanxi P. R. China
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Chiu CY, Chen YC, Wu KW, Hsu WC, Lin HP, Chang HC, Lee YC, Wang YK, Tu TY. Simple In-House Fabrication of Microwells for Generating Uniform Hepatic Multicellular Cancer Aggregates and Discovering Novel Therapeutics. MATERIALS (BASEL, SWITZERLAND) 2019; 12:E3308. [PMID: 31614495 PMCID: PMC6829256 DOI: 10.3390/ma12203308] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/07/2019] [Revised: 09/30/2019] [Accepted: 10/05/2019] [Indexed: 12/24/2022]
Abstract
Three-dimensional (3D) cell culture models have become powerful tools because they better simulate the in vivo pathophysiological microenvironment than traditional two-dimensional (2D) monolayer cultures. Tumor cells cultured in a 3D system as multicellular cancer aggregates (MCAs) recapitulate several critical in vivo characteristics that enable the study of biological functions and drug discovery. The microwell, in particular, has emerged as a revolutionary technology in the generation of MCAs as it provides geometrically defined microstructures for culturing size-controlled MCAs amenable for various downstream functional assays. This paper presents a simple and economical microwell fabrication methodology that can be conveniently incorporated into a conventional laboratory setting and used for the discovery of therapeutic interventions for liver cancer. The microwells were 400-700 µm in diameter, and hepatic MCAs (Huh-7 cells) were cultured in them for up to 5 days, over which time they grew to 250-520 µm with good viability and shape. The integrability of the microwell fabrication with a high-throughput workflow was demonstrated using a standard 96-well plate for proof-of-concept drug screening. The IC50 of doxorubicin was determined to be 9.3 µM under 2D conditions and 42.8 µM under 3D conditions. The application of photothermal treatment was demonstrated by optimizing concanavalin A-FITC conjugated silica-carbon hollow spheres (SCHSs) at a concentration of 500:200 µg/mL after a 2 h incubation to best bind with MCAs. Based on this concentration, which was appropriate for further photothermal treatment, the relative cell viability was assessed through exposure to a 3 W/cm2 near-infrared laser for 20 min. The relative fluorescence intensity showed an eight-fold reduction in cell viability, confirming the feasibility of using photothermal treatment as a potential therapeutic intervention. The proposed microwell integration is envisioned to serve as a simple in-house technique for the generation of MCAs useful for discovering therapeutic modalities for liver cancer treatment.
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Affiliation(s)
- Chiao-Yi Chiu
- Department of Biomedical Engineering, National Cheng Kung University, Tainan 70101, Taiwan (Y.-C.C.); (K.-W.W.); (W.-C.H.)
| | - Ying-Chi Chen
- Department of Biomedical Engineering, National Cheng Kung University, Tainan 70101, Taiwan (Y.-C.C.); (K.-W.W.); (W.-C.H.)
| | - Kuang-Wei Wu
- Department of Biomedical Engineering, National Cheng Kung University, Tainan 70101, Taiwan (Y.-C.C.); (K.-W.W.); (W.-C.H.)
| | - Wen-Chien Hsu
- Department of Biomedical Engineering, National Cheng Kung University, Tainan 70101, Taiwan (Y.-C.C.); (K.-W.W.); (W.-C.H.)
| | - Hong-Ping Lin
- Department of Chemistry, National Cheng Kung University, Tainan 70101, Taiwan;
| | - Hsien-Chang Chang
- Department of Biomedical Engineering, National Cheng Kung University, Tainan 70101, Taiwan (Y.-C.C.); (K.-W.W.); (W.-C.H.)
- Medical Device Innovation Center, National Cheng Kung University, Tainan 70101, Taiwan
- Center for Micro/Nano Technology Research, National Cheng Kung University, Tainan 70101, Taiwan
| | - Yung-Chun Lee
- Center for Micro/Nano Technology Research, National Cheng Kung University, Tainan 70101, Taiwan
- Department of Mechanical Engineering, National Cheng Kung University, Tainan 70101, Taiwan;
| | - Yang-Kao Wang
- Department of Cell Biology and Anatomy, College of Medicine, National Cheng Kung University, Tainan 70101, Taiwan;
| | - Ting-Yuan Tu
- Department of Biomedical Engineering, National Cheng Kung University, Tainan 70101, Taiwan (Y.-C.C.); (K.-W.W.); (W.-C.H.)
- Medical Device Innovation Center, National Cheng Kung University, Tainan 70101, Taiwan
- Center for Micro/Nano Technology Research, National Cheng Kung University, Tainan 70101, Taiwan
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18
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Lee SW, Jeong SY, Shin TH, Min J, Lee D, Jeong GS. A cell-loss-free concave microwell array based size-controlled multi-cellular tumoroid generation for anti-cancer drug screening. PLoS One 2019; 14:e0219834. [PMID: 31344058 PMCID: PMC6658056 DOI: 10.1371/journal.pone.0219834] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Accepted: 07/03/2019] [Indexed: 12/20/2022] Open
Abstract
The 3D multi-cellular tumoroid (MCT) model is an in vivo-like, avascular tumor model that has received much attention as a refined screening platform for drug therapies. Several types of research have been efforted to improve the physiological characteristics of the tumor microenvironment (TME) of the in vivo-like MCTs. Size-controlled MCTs have received much attention for obtaining highly reproducible results in drug screening assays and achieving a homogeneous and meaningful level of biological activities. Here, we describe an effective method for fabricating the size-controlled in vivo-like MCTs using a cell-loss-free (CLF) microwell arrays. The CLF microwell arrays was fabricated by using the simple operation of laser carving of a poly (methyl methacrylate) (PMMA) master mold. We also demonstrated the biophysicochemical effect of tumor microenvironment (TME) resident fibroblasts through the expression of TGFβ, αSMA, Type I-, IV collagen, angiogenesis related markers on tumorigenesis, and confirmed the drug response of MCTs with anti-cancer agents. This technology for the fabrication of CLF microwell arrays could be used as an effective method to produce an in vitro tumor model for cancer research and drug discovery.
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Affiliation(s)
- Sang Woo Lee
- Biomedical Engineering Research Center, Asan Institute for Life Sciences, Asan Medical Center, Seoul, Korea
| | - Soo Yeon Jeong
- Biomedical Engineering Research Center, Asan Institute for Life Sciences, Asan Medical Center, Seoul, Korea
| | - Tae Hoon Shin
- Biomedical Engineering Research Center, Asan Institute for Life Sciences, Asan Medical Center, Seoul, Korea
| | - Junhong Min
- School of Integrative Engineering, Department of Biomedical Engineering, Chung-Ang University, Seoul, Korea
| | - Donghyun Lee
- School of Integrative Engineering, Department of Biomedical Engineering, Chung-Ang University, Seoul, Korea
| | - Gi Seok Jeong
- Biomedical Engineering Research Center, Asan Institute for Life Sciences, Asan Medical Center, Seoul, Korea
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