1
|
Takuma M, Fujita H, Zushi N, Nagano H, Azuma R, Kiyosawa T, Fujie T. An intrinsically semi-permeable PDMS nanosheet encapsulating adipose tissue-derived stem cells for enhanced angiogenesis. Biomater Sci 2024. [PMID: 38804980 DOI: 10.1039/d4bm00460d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
Cell encapsulation devices are expected to be promising tools that can control the release of therapeutic proteins secreted from transplanted cells. The protein permeability of the device membrane is important because it allows the isolation of transplanted cells while enabling the effectiveness of the device. In this study, we investigated free-standing polymeric ultra-thin films (nanosheets) as an intrinsically semi-permeable membrane made from polydimethylsiloxane (PDMS). The PDMS nanosheet with a thickness of 600 nm showed intrinsic protein permeability, and the device fabricated with the PDMS nanosheet showed that VEGF secreted from implanted adipose tissue-derived stem cells (ASCs) could be released for at least 5 days. The ASC encapsulation device promoted angiogenesis and the development of granulation tissue 1 week after transplantation to the subcutaneous area of a mouse. This cell encapsulation device consisting of PDMS nanosheets provides a new method for pre-vascularization of the subcutaneous area in cell transplantation therapy.
Collapse
Affiliation(s)
- Megumi Takuma
- School of Life Science and Technology, Tokyo Institute of Technology, B-50, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan.
| | - Hajime Fujita
- School of Life Science and Technology, Tokyo Institute of Technology, B-50, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan.
| | - Nanami Zushi
- School of Life Science and Technology, Tokyo Institute of Technology, B-50, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan.
| | - Hisato Nagano
- Department of Plastic and Reconstructive Surgery, National Defense Medical College, Tokorozawa, Saitama 359-8513, Japan
| | - Ryuichi Azuma
- Department of Plastic and Reconstructive Surgery, National Defense Medical College, Tokorozawa, Saitama 359-8513, Japan
| | - Tomoharu Kiyosawa
- Department of Plastic and Reconstructive Surgery, National Defense Medical College, Tokorozawa, Saitama 359-8513, Japan
| | - Toshinori Fujie
- School of Life Science and Technology, Tokyo Institute of Technology, B-50, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan.
- Research Center for Autonomous Systems Materialogy (ASMat), Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan
| |
Collapse
|
2
|
Medina-Ramirez IE, Macias-Diaz JE, Masuoka-Ito D, Zapien JA. Holotomography and atomic force microscopy: a powerful combination to enhance cancer, microbiology and nanotoxicology research. DISCOVER NANO 2024; 19:64. [PMID: 38594446 PMCID: PMC11003950 DOI: 10.1186/s11671-024-04003-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2023] [Accepted: 03/23/2024] [Indexed: 04/11/2024]
Abstract
Modern imaging strategies are paramount to studying living systems such as cells, bacteria, and fungi and their response to pathogens, toxicants, and nanomaterials (NMs) as modulated by exposure and environmental factors. The need to understand the processes and mechanisms of damage, healing, and cell survivability of living systems continues to motivate the development of alternative imaging strategies. Of particular interest is the use of label-free techniques (microscopy procedures that do not require sample staining) that minimize interference of biological processes by foreign marking substances and reduce intense light exposure and potential photo-toxicity effects. This review focuses on the synergic capabilities of atomic force microscopy (AFM) as a well-developed and robust imaging strategy with demonstrated applications to unravel intimate details in biomedical applications, with the label-free, fast, and enduring Holotomographic Microscopy (HTM) strategy. HTM is a technique that combines holography and tomography using a low intensity continuous illumination laser to investigate (quantitatively and non-invasively) cells, microorganisms, and thin tissue by generating three-dimensional (3D) images and monitoring in real-time inner morphological changes. We first review the operating principles that form the basis for the complementary details provided by these techniques regarding the surface and internal information provided by HTM and AFM, which are essential and complimentary for the development of several biomedical areas studying the interaction mechanisms of NMs with living organisms. First, AFM can provide superb resolution on surface morphology and biomechanical characterization. Second, the quantitative phase capabilities of HTM enable superb modeling and quantification of the volume, surface area, protein content, and mass density of the main components of cells and microorganisms, including the morphology of cells in microbiological systems. These capabilities result from directly quantifying refractive index changes without requiring fluorescent markers or chemicals. As such, HTM is ideal for long-term monitoring of living organisms in conditions close to their natural settings. We present a case-based review of the principal uses of both techniques and their essential contributions to nanomedicine and nanotoxicology (study of the harmful effects of NMs in living organisms), emphasizing cancer and infectious disease control. The synergic impact of the sequential use of these complementary strategies provides a clear drive for adopting these techniques as interdependent fundamental tools.
Collapse
Affiliation(s)
- Iliana E Medina-Ramirez
- Department of Chemistry, Universidad Autónoma de Aguascalientes, Av. Universidad 940, Aguascalientes, Ags, Mexico.
| | - J E Macias-Diaz
- Department of Mathematics and Physics, Universidad Autónoma de Aguascalientes, Av. Universidad 940, Aguascalientes, Ags, Mexico
| | - David Masuoka-Ito
- Department of Stomatology, Universidad Autónoma de Aguascalientes, Av. Universidad 940, Aguascalientes, Ags, Mexico
| | - Juan Antonio Zapien
- Department of Materials Science and Engineering, City University of Hong Kong, Kowloon, Hong Kong SAR, People's Republic of China.
| |
Collapse
|
3
|
Gao Y, Zhong M, Yu J, Zhao Z, Yu C, Yu Q, Yao F, Li J, Zhang H. Large-Scale Fabrication of Freestanding Polymer Ultrathin Porous Membranes for Transparent Transwell Coculture Systems. ACS NANO 2024; 18:8168-8179. [PMID: 38437515 DOI: 10.1021/acsnano.3c11946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/06/2024]
Abstract
Advancements in cell coculture systems with porous membranes have facilitated the simulation of human-like in vitro microenvironments for diverse biomedical applications. However, conventional Transwell membranes face limitations in low porosity (ca. 6%) and optical opacity due to their large thickness (ca. 10 μm). In this study, we demonstrated a one-step, large-scale fabrication of freestanding polymer ultrathin porous (PUP) membranes with thicknesses of hundreds of nanometers. PUP membranes were produced by using a gap-controlled bar-coating process combined with polymer blend phase separation. They are 20 times thinner than Transwell membranes, possessing 3-fold higher porosity and exhibiting high transparency. These membranes demonstrate outstanding molecular permeability and significantly reduce the cell-cell distance, thereby facilitating efficient signal exchange pathways between cells. This research enables the establishment of a cutting-edge in vitro cell coculture system, enhancing optical transparency, and streamlining the large-scale manufacturing of porous membranes.
Collapse
Affiliation(s)
- Yi Gao
- School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China
| | - Mengyao Zhong
- School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China
| | - Jiajun Yu
- School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China
| | - Zhongming Zhao
- School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China
| | - Chaojie Yu
- School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China
| | - Qingyu Yu
- School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China
- Tianjin Key Laboratory of Biomedical Materials, Institute of Biomedical Engineering, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin 300192, China
| | - Fanglian Yao
- School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering, Ministry of Education, Tianjin University, Tianjin 300350, China
| | - Junjie Li
- School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering, Ministry of Education, Tianjin University, Tianjin 300350, China
| | - Hong Zhang
- School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering, Ministry of Education, Tianjin University, Tianjin 300350, China
| |
Collapse
|
4
|
Mancinelli E, Zushi N, Takuma M, Cheng Chau CC, Parpas G, Fujie T, Pensabene V. Porous Polymeric Nanofilms for Recreating the Basement Membrane in an Endothelial Barrier-on-Chip. ACS APPLIED MATERIALS & INTERFACES 2024; 16:13006-13017. [PMID: 38414331 PMCID: PMC10941076 DOI: 10.1021/acsami.3c16134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2023] [Revised: 01/25/2024] [Accepted: 01/26/2024] [Indexed: 02/29/2024]
Abstract
Organs-on-chips (OoCs) support an organotypic human cell culture in vitro. Precise representation of basement membranes (BMs) is critical for mimicking physiological functions of tissue interfaces. Artificial membranes in polyester (PES) and polycarbonate (PC) commonly used in in vitro models and OoCs do not replicate the characteristics of the natural BMs, such as submicrometric thickness, selective permeability, and elasticity. This study introduces porous poly(d,l-lactic acid) (PDLLA) nanofilms for replicating BMs in in vitro models and demonstrates their integration into microfluidic chips. Using roll-to-roll gravure coating and polymer phase separation, we fabricated transparent ∼200 nm thick PDLLA films. These nanofilms are 60 times thinner and 27 times more elastic than PES membranes and show uniformly distributed pores of controlled diameter (0.4 to 1.6 μm), which favor cell compartmentalization and exchange of large water-soluble molecules. Human umbilical vein endothelial cells (HUVECs) on PDLLA nanofilms stretched across microchannels exhibited 97% viability, enhanced adhesion, and a higher proliferation rate compared to their performance on PES membranes and glass substrates. After 5 days of culture, HUVECs formed a functional barrier on suspended PDLLA nanofilms, confirmed by a more than 10-fold increase in transendothelial electrical resistance and blocked 150 kDa dextran diffusion. When integrated between two microfluidic channels and exposed to physiological shear stress, despite their ultrathin thickness, PDLLA nanofilms upheld their integrity and efficiently maintained separation of the channels. The successful formation of an adherent endothelium and the coculture of HUVECs and human astrocytes on either side of the suspended nanofilm validate it as an artificial BM for OoCs. Its submicrometric thickness guarantees intimate contact, a key feature to mimic the blood-brain barrier and to study paracrine signaling between the two cell types. In summary, porous PDLLA nanofilms hold the potential for improving the accuracy and physiological relevance of the OoC as in vitro models and drug discovery tools.
Collapse
Affiliation(s)
- Elena Mancinelli
- School
of Electronic and Electrical Engineering and Pollard Institute, University of Leeds, Leeds LS2 9JT, United Kingdom
- Bragg
Centre for Materials Research, University
of Leeds, Leeds LS2 9JT, United Kingdom
| | - Nanami Zushi
- School
of Life Science and Technology, Tokyo Institute
of Technology, B-50, Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan
| | - Megumi Takuma
- School
of Life Science and Technology, Tokyo Institute
of Technology, B-50, Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan
| | - Chalmers Chi Cheng Chau
- School
of Electronic and Electrical Engineering and Pollard Institute, University of Leeds, Leeds LS2 9JT, United Kingdom
- Bragg
Centre for Materials Research, University
of Leeds, Leeds LS2 9JT, United Kingdom
- School
of Molecular and Cellular Biology and Astbury Centre for Structural
Molecular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - George Parpas
- School
of Electronic and Electrical Engineering and Pollard Institute, University of Leeds, Leeds LS2 9JT, United Kingdom
- Bragg
Centre for Materials Research, University
of Leeds, Leeds LS2 9JT, United Kingdom
- Leeds
Institute of Biomedical and Clinical Sciences, University of Leeds, Leeds LS2 9JT, United
Kingdom
| | - Toshinori Fujie
- School
of Life Science and Technology, Tokyo Institute
of Technology, B-50, Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan
- Living Systems
Materialogy (LiSM) Research Group, International Research Frontiers
Initiative (IRFI), Tokyo Institute of Technology, R3-23, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8503, Japan
| | - Virginia Pensabene
- School
of Electronic and Electrical Engineering and Pollard Institute, University of Leeds, Leeds LS2 9JT, United Kingdom
- Bragg
Centre for Materials Research, University
of Leeds, Leeds LS2 9JT, United Kingdom
- Faculty
of Medicine and Health, Leeds Institute of Medical Research at St
James’s University Hospital, University of Leeds, Leeds LS2 9JT, United Kingdom
| |
Collapse
|
5
|
Badekila AK, Pai V, Vijayan V, Kini S. Engineering alginate/carboxymethylcellulose scaffolds to establish liver cancer spheroids: Evaluation of molecular variances between 2D and 3D models. Int J Biol Macromol 2024; 254:128058. [PMID: 37956801 DOI: 10.1016/j.ijbiomac.2023.128058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 09/15/2023] [Accepted: 11/10/2023] [Indexed: 11/15/2023]
Abstract
Natural polymeric hydrogels represent an optimal framework for 3D culture development. This study demonstrates a freeze-thaw-based ionic crosslinking technique for fabricating alginate/carboxymethylcellulose scaffold for culturing human hepatocellular carcinoma, Huh-7 cells to generate 3D spheroids. Consolidating morphological and biomechanical characterization of Alg/CMC scaffolds shows the formation of uniform hydrogels with significant crosslinking (ATR-FTIR), multiscale pores (FE-SEM), swelling/water absorbance, softer texture, viscoelasticity (rheology), spreading nature (contact angle), and degradation rate optimal for 3D culture establishment. The influence of cell seeding density and time with spheroid formation reveals a maximal size of 250-300 μm on day 7. Calcein AM and Propidium iodide staining confirm that a culmination of viable and dead cells generates spheroidal heterogeneity. RT-qPCR in 3D culture against RPL-13 and 2D culture controls indicate an upregulation of E-cadherin, N-cadherin, fibronectin, and integrin α9/β6. Further, western blotting and immunofluorescence confirm the collective display of cellular interactions in 3D spheroids. Thus, the expression profile signifies the role of key genes during the assembly and formation of 3D spheroids in 1%Alg/1%CMC scaffolds with a profound epithelial characteristic. In the future, this study will bring a 3D spheroid model in a platter for elucidating epithelial to mesenchymal transition of cells during in vitro disease modeling.
Collapse
Affiliation(s)
- Anjana Kaveri Badekila
- Nitte (Deemed to be University), Department of Bio & Nano Technology, Nitte University Centre for Science Education and Research, Mangalore 575018, Karnataka, India
| | - Vishruta Pai
- Nitte (Deemed to be University), Department of Bio & Nano Technology, Nitte University Centre for Science Education and Research, Mangalore 575018, Karnataka, India
| | - Vijeesh Vijayan
- Nitte (Deemed to be University), Department of Mechanical Engineering, NMAM Institute of Technology (NMAMIT), Nitte 574110, India
| | - Sudarshan Kini
- Nitte (Deemed to be University), Department of Bio & Nano Technology, Nitte University Centre for Science Education and Research, Mangalore 575018, Karnataka, India.
| |
Collapse
|
6
|
Badekila AK, Pai V, Vijayan V, Kini S. Engineering alginate/carboxymethylcellulose scaffolds to establish liver cancer spheroids: Evaluation of molecular variances between 2D and 3D models. Int J Biol Macromol 2023:128058. [DOI: https:/doi.org/10.1016/j.ijbiomac.2023.128058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2023]
|
7
|
Cho YW, Jee S, Suhito IR, Lee JH, Park CG, Choi KM, Kim TH. Single metal-organic framework-embedded nanopit arrays: A new way to control neural stem cell differentiation. SCIENCE ADVANCES 2022; 8:eabj7736. [PMID: 35442746 PMCID: PMC9020781 DOI: 10.1126/sciadv.abj7736] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Accepted: 03/04/2022] [Indexed: 05/31/2023]
Abstract
Stable and continuous supply of essential biomolecules is critical to mimic in vivo microenvironments wherein spontaneous generation of various cell types occurs. Here, we report a new platform that enables highly efficient neuronal cell generation of neural stem cells using single metal-organic framework (MOF) nanoparticle-embedded nanopit arrays (SMENA). By optimizing the physical parameters of homogeneous periodic nanopatterns, each nanopit can confine single nMOFs (UiO-67) that are specifically designed for long-term storage and release of retinoic acid (RA). The SMENA platform successfully inhibited physical interaction with cells, which contributed to remarkable stability of the nMOF (RA⊂UiO-67) structure without inducing nanoparticle-mediated toxicity issues. Owing to the continuous and long-term supply of RA, the neural stem cells showed enhanced mRNA expressions of various neurogenesis-related activities. The developed SMENA platform can be applied to other stem cell sources and differentiation lineages and is therefore useful for various stem cell-based regenerative therapies.
Collapse
Affiliation(s)
- Yeon-Woo Cho
- School of Integrative Engineering, Chung-Ang University, 84 Heukseuk-ro, Dongjak-gu, Seoul 06974, Republic of Korea
| | - Seohyeon Jee
- Department of Chemical and Biological Engineering, Sookmyung Women’s University, 100 Cheongpa-ro 47-gil, Yongsan-gu, Seoul 04310, Republic of Korea
| | - Intan Rosalina Suhito
- School of Integrative Engineering, Chung-Ang University, 84 Heukseuk-ro, Dongjak-gu, Seoul 06974, Republic of Korea
| | - Jeong-Hyeon Lee
- School of Integrative Engineering, Chung-Ang University, 84 Heukseuk-ro, Dongjak-gu, Seoul 06974, Republic of Korea
| | - Chun Gwon Park
- Department of Biomedical Engineering, SKKU Institute for Convergence, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
- Department of Intelligent Precision Healthcare Convergence, SKKU Institute for Convergence, ungkyunkwan University (SKKU) , Suwon, Gyeonggi 16419, Republic of Korea
| | - Kyung Min Choi
- Department of Chemical and Biological Engineering, Sookmyung Women’s University, 100 Cheongpa-ro 47-gil, Yongsan-gu, Seoul 04310, Republic of Korea
- LabInCube Co. Ltd., A304-C2, 45, Yangcheong 4-gil, Ochang-eup, Cheongwon-gu, Cheongju-si, Chungcheongbuk-do, Republic of Korea
| | - Tae-Hyung Kim
- School of Integrative Engineering, Chung-Ang University, 84 Heukseuk-ro, Dongjak-gu, Seoul 06974, Republic of Korea
| |
Collapse
|
8
|
Suematsu Y, Nagano H, Kiyosawa T, Takeoka S, Fujie T. Angiogenic efficacy of ASC spheroids filtrated on porous nanosheets for the treatment of a diabetic skin ulcer. J Biomed Mater Res B Appl Biomater 2021; 110:1245-1254. [PMID: 34931751 DOI: 10.1002/jbm.b.34995] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 11/30/2021] [Accepted: 12/05/2021] [Indexed: 11/09/2022]
Abstract
Stem cell transplantation is expected to be an effective treatment for intractable skin ulcers by promoting angiogenesis; however, it is challenging to quickly realize a sufficient bloodstream for the ulcers. For this treatment, sheet-like materials with monolayer cells such as cell sheets have been investigated. However, they have a limitation of cell number that can be transplanted at one time due to the two-dimensional, monolayer cell structure, and sufficient secretion of growth factors cannot be expected. In this regard, cellular aggregates, such as spheroids, can reproduce three-dimensional cell-cell interactions that cause biological functions of living tissues more representative than monolayer cells, which is important to achieving efficient secretion of growth factors. In this study, we focused on free-standing porous polymer ultrathin films ("porous nanosheets") comprising poly(d,l-lactic acid) (PDLLA) and succeeded in developing a spheroid-covered nanosheet, on which more than 1000 spheroids from adipose-tissue derived stem cells (ASCs) were loaded. The porous structure with an average pore diameter of 4 μm allowed for facile filtration and carrying spheroids on the nanosheet, as well as sufficient oxygen and nutrients inflow to the cells. The spheroid-covered nanosheet achieved homogeneous transference of spheroids to a whole skin defect in diabetic model mice. Given the continuous release of vascular endothelial growth factor (VEGF) from the spheroids, the transplanted spheroids promoted healing with more accelerated angiogenesis than a nanosheet with a monolayer of cells. The spheroid-covered nanosheet may be a new regenerative material for promoting intractable skin ulcer healing.
Collapse
Affiliation(s)
- Yoshitaka Suematsu
- Graduate School of Advanced Science and Engineering, Waseda University, Tokyo, Japan
| | - Hisato Nagano
- Department of Plastic Surgery, National Defense Medical College, Saitama, Japan
| | - Tomoharu Kiyosawa
- Department of Plastic Surgery, National Defense Medical College, Saitama, Japan
| | - Shinji Takeoka
- Graduate School of Advanced Science and Engineering, Waseda University, Tokyo, Japan.,Institute for Advanced Research of Biosystem Dynamics, Research Institute for Science and Engineering, Waseda University, Tokyo, Japan
| | - Toshinori Fujie
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan.,Research Organization for Nano & Life Innovation, Waseda University, Tokyo, Japan
| |
Collapse
|
9
|
Tsai YA, Li T, Torres-Fernández LA, Weise SC, Kolanus W, Takeoka S. Ultra-Thin Porous PDLLA Films Promote Generation, Maintenance, and Viability of Stem Cell Spheroids. Front Bioeng Biotechnol 2021; 9:674384. [PMID: 34195179 PMCID: PMC8236593 DOI: 10.3389/fbioe.2021.674384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 05/05/2021] [Indexed: 11/13/2022] Open
Abstract
Three-dimensional (3D) culture bridges and minimizes the gap between in vitro and in vivo states of cells and various 3D culture systems have been developed according to different approaches. However, most of these approaches are either complicated to operate, or costive to scale up. Therefore, a simple method for stem cell spheroid formation and preservation was proposed using poly(D,L-lactic acid) porous thin film (porous nanosheet), which were fabricated by a roll-to-roll gravure coating method combining a solvent etching process. The obtained porous nanosheet was less than 200 nm in thickness and had an average pore area of 6.6 μm2 with a porosity of 0.887. It offered a semi-adhesive surface for stem cells to form spheroids and maintained the average spheroid diameter below 100 μm for 5 days. In comparison to the spheroids formed in suspension culture, the porous nanosheets improved cell viability and cell division rate, suggesting the better feasibility to be applied as 3D culture scaffolds.
Collapse
Affiliation(s)
- Ya An Tsai
- Department of Life Science and Medical Bioscience, Graduate School of Advanced Science and Engineering, Waseda University (TWIns), Tokyo, Japan
| | - Tianshu Li
- Institute for Advanced Research of Biosystem Dynamics, Research Institute for Science and Engineering, Waseda University, Tokyo, Japan
| | | | - Stefan C Weise
- Life and Medical Sciences Institute (LIMES), University of Bonn, Bonn, Germany
| | - Waldemar Kolanus
- Life and Medical Sciences Institute (LIMES), University of Bonn, Bonn, Germany
| | - Shinji Takeoka
- Department of Life Science and Medical Bioscience, Graduate School of Advanced Science and Engineering, Waseda University (TWIns), Tokyo, Japan.,Institute for Advanced Research of Biosystem Dynamics, Research Institute for Science and Engineering, Waseda University, Tokyo, Japan
| |
Collapse
|