1
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Dufva M. A quantitative meta-analysis comparing cell models in perfused organ on a chip with static cell cultures. Sci Rep 2023; 13:8233. [PMID: 37217582 DOI: 10.1038/s41598-023-35043-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Accepted: 05/11/2023] [Indexed: 05/24/2023] Open
Abstract
As many consider organ on a chip for better in vitro models, it is timely to extract quantitative data from the literature to compare responses of cells under flow in chips to corresponding static incubations. Of 2828 screened articles, 464 articles described flow for cell culture and 146 contained correct controls and quantified data. Analysis of 1718 ratios between biomarkers measured in cells under flow and static cultures showed that the in all cell types, many biomarkers were unregulated by flow and only some specific biomarkers responded strongly to flow. Biomarkers in cells from the blood vessels walls, the intestine, tumours, pancreatic island, and the liver reacted most strongly to flow. Only 26 biomarkers were analysed in at least two different articles for a given cell type. Of these, the CYP3A4 activity in CaCo2 cells and PXR mRNA levels in hepatocytes were induced more than two-fold by flow. Furthermore, the reproducibility between articles was low as 52 of 95 articles did not show the same response to flow for a given biomarker. Flow showed overall very little improvements in 2D cultures but a slight improvement in 3D cultures suggesting that high density cell culture may benefit from flow. In conclusion, the gains of perfusion are relatively modest, larger gains are linked to specific biomarkers in certain cell types.
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Affiliation(s)
- Martin Dufva
- Department of Health Technology, Technical University of Denmark, 2800, Kgs Lyngby, Denmark.
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2
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Niora M, Lerche MH, Dufva M, Berg-Sørensen K. Quantitative Evaluation of the Cellular Uptake of Nanodiamonds by Monocytes and Macrophages. Small 2023; 19:e2205429. [PMID: 36638251 DOI: 10.1002/smll.202205429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 11/28/2022] [Indexed: 06/17/2023]
Abstract
Fluorescent nanodiamonds (FNDs) with negative nitrogen-vacancy (NV- ) defect centers are great probes for biosensing applications, with potential to act as biomarkers for cell differentiation. To explore this concept, uptake of FNDs (≈120 nm) by THP-1 monocytes and monocyte-derived M0-macrophages is studied. The time course analysis of FND uptake by monocytes confirms differing FND-cell interactions and a positive time-dependence. No effect on cell viability, proliferation, and differentiation potential into macrophages is observed, while cells saturated with FNDs, unload the FNDs completely by 25 cell divisions and subsequently take up a second dose effectively. FND uptake variations by THP-1 cells at early exposure-times indicate differing phagocytic capability. The cell fraction that exhibits relatively enhanced FND uptake is associated to a macrophage phenotype which derives from spontaneous monocyte differentiation. In accordance, chemical-differentiation of the THP-1 cells into M0-macrophages triggers increased and homogeneous FND uptake, depleting the fraction of cells that were non-responsive to FNDs. These observations imply that FND uptake allows for distinction between the two cell subtypes based on phagocytic capacity. Overall, FNDs demonstrate effective cell labeling of monocytes and macrophages, and are promising candidates for sensing biological processes that involve cell differentiation.
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Affiliation(s)
- Maria Niora
- Department of Health Technology, Technical University of Denmark, Ørsteds Plads, building 345C, 2800, Kgs. Lyngby, Denmark
| | - Mathilde Hauge Lerche
- Department of Health Technology, Technical University of Denmark, Ørsteds Plads, building 345C, 2800, Kgs. Lyngby, Denmark
| | - Martin Dufva
- Department of Health Technology, Technical University of Denmark, Ørsteds Plads, building 345C, 2800, Kgs. Lyngby, Denmark
| | - Kirstine Berg-Sørensen
- Department of Health Technology, Technical University of Denmark, Ørsteds Plads, building 345C, 2800, Kgs. Lyngby, Denmark
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3
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Dogan AA, Dufva M. Heterogenous morphogenesis of Caco-2 cells reveals that flow induces three-dimensional growth and maturation at high initial seeding cell densities. Biotechnol Bioeng 2023; 120:1667-1677. [PMID: 36815727 DOI: 10.1002/bit.28362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 01/25/2023] [Accepted: 02/21/2023] [Indexed: 02/24/2023]
Abstract
Here, we introduce a customized hanging insert fitting a six-well plate to culture Caco-2 cells on hydrogel membranes under flow conditions. The cells are cultured in the apical channel-like chamber, which provides about 1.3 dyn/cm2 shear, while the basolateral chamber is mixed when the device is rocked. The device was tested by investigating the functional impact of the initial seeding density in combination with flow applied at confluency. The low seeding density cultures grew in two dimensional (2D) irrespective of the flow. Flow and higher seeding density resulted in a mixture of three dimensional (3D) structures and 2D layers. Static culture and high cell seeding density resulted in 2D layers. The flow increased the height and ZO-1 expression of cells in 2D layers, which correlated with an improved barrier function. Cultures with 3D structures had higher ZO-1 expression than 2D cultures, but this did not correlate with an increased barrier function. 2D monolayers in static and dynamic cultures had similar morphology and heterogeneity in the expression of Mucin-2 and Villin, while the 3D structures had generally higher expression of these markers. The result shows that the cell density and flow determine 3D growth and that the highest barrier function was obtained with low-density cultures and flow.
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Affiliation(s)
- Asli Aybike Dogan
- Department of Health Technology, Technical University of Denmark, Lyngby, Denmark
| | - Martin Dufva
- Department of Health Technology, Technical University of Denmark, Lyngby, Denmark
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4
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Dogan AA, Dufva M. Author Correction: Customized 3D-printed stackable cell culture inserts tailored with bioactive membranes. Sci Rep 2022; 12:5803. [PMID: 35388119 PMCID: PMC8986841 DOI: 10.1038/s41598-022-09955-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Asli Aybike Dogan
- Department of Health Technology, Technical University of Denmark, 2800, Kgs. Lyngby, Denmark
| | - Martin Dufva
- Department of Health Technology, Technical University of Denmark, 2800, Kgs. Lyngby, Denmark.
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5
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Dogan AA, Dufva M. Customized 3D-printed stackable cell culture inserts tailored with bioactive membranes. Sci Rep 2022; 12:3694. [PMID: 35256703 PMCID: PMC8901659 DOI: 10.1038/s41598-022-07739-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 02/16/2022] [Indexed: 11/26/2022] Open
Abstract
There is a high demand in various fields to develop complex cell cultures. Apart from titer plates, Transwell inserts are the most popular device because they are commercially available, easy to use, and versatile. While Transwell inserts are standardized, there are potential gains to customize inserts in terms of the number of layers, height between the layers and the size and composition of the bioactive membrane. To demonstrate such customization, we present a small library of 3D-printed inserts and a robust method to functionalize the inserts with hydrogel and synthetic membrane materials. The library consists of 24- to 96-well sized inserts as whole plates, strips, and singlets. The density of cultures (the number of wells per plate) and the number of layers was decided by the wall thickness, the capillary forces between the layers and the ability to support fluid operations. The highest density for a two-layer culture was 48-well plate format because the corresponding 96-well format could not support fluidic operations. The bottom apertures were functionalized with hydrogels using a new high-throughput dip-casting technique. This yielded well-defined hydrogel membranes in the apertures with a thickness of about 500 µm and a %CV (coefficient of variance) of < 10%. Consistent intestine barrier was formed on the gelatin over 3-weeks period. Furthermore, mouse intestinal organoid development was compared on hydrogel and synthetic filters glued to the bottom of the 3D-printed inserts. Condensation was most pronounced in inserts with filters followed by the gelatin membrane and the control, which were organoids cultured at the bottom of a titer plate well. This showed that the bottom of an insert should be chosen based on the application. All the inserts were fabricated using an easy-to-use stereolithography (SLA) printer commonly used for dentistry and surgical applications. Therefore, on demand printing of the customized inserts is realistic in many laboratory settings.
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Affiliation(s)
- Asli Aybike Dogan
- Department of Health Technology, Technical University of Denmark, 2800, Kgs. Lyngby, Denmark
| | - Martin Dufva
- Department of Health Technology, Technical University of Denmark, 2800, Kgs. Lyngby, Denmark.
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6
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Toppi A, Dufva M. Accessible, fast and easy fabrication of hydrophilic-in-hydrophobic microdroplet arrays. PLoS One 2022; 17:e0263282. [PMID: 35213568 PMCID: PMC8880433 DOI: 10.1371/journal.pone.0263282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Accepted: 01/16/2022] [Indexed: 11/18/2022] Open
Abstract
Microdroplet arrays (MDAs) are powerful tools for digital immunoassays, high-throughput screening and single cell analysis. However, MDAs are usually produced with cleanroom processes, which are associated with high costs and low availability. Furthermore, in order to obtain robust and stable MDAs based on hydrophilic spots surrounded by a hydrophobic background, the chemistry must be strictly controlled, which is challenging using shared equipment. Here, we developed a new method to fabricate MDA substrates independently from the cleanroom. A small and low-cost in-house built system to collimate the light source was assembled for photopatterning a negative resist, and spots with diameters down to 4 μm were obtained, with only 3% to 5% spot-to-spot variation across the same sample and high batch-to-batch reproducibility. The use of a negative photoresist enabled the formation of a hydrophobic coating in solution which yielded high-quality MDAs. The feasibility for carrying out digital assays was demonstrated by measuring anti-Tau antibody in sample buffers containing bovine serum albumin, with no noticeable surface fouling. The reported, robust, cost-effective, and fast process could hence lower the threshold to fabricate and use MDAs for digital immunoassays and other microcompartmentalization-based applications.
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Affiliation(s)
- Arianna Toppi
- Department of Health Technology, Technical University of Denmark, Lyngby, Denmark
| | - Martin Dufva
- Department of Health Technology, Technical University of Denmark, Lyngby, Denmark
- * E-mail:
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7
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Bazban-Shotorbani S, Gavins F, Kant K, Dufva M, Kamaly N. A Biomicrofluidic Screening Platform for Dysfunctional Endothelium‐Targeted Nanoparticles and Therapeutics. Advanced NanoBiomed Research 2022. [DOI: 10.1002/anbr.202270011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Affiliation(s)
- Salime Bazban-Shotorbani
- Department of Health Technology DTU Health Tech Technical University of Denmark Lyngby 2800 Kgs. Denmark
- Department of Chemistry Molecular Sciences Research Hub (MSRH) Imperial College London London W12 0BZ UK
| | - Felicity Gavins
- Department of Life Sciences Centre for Inflammation Research and Translational Medicine (CIRTM) Brunel University London London UB8 3PH UK
| | - Krishna Kant
- Department of Physical Chemistry Biomedical Research Center of Galicia (CINBIO) University of Vigo Vigo 36310 Spain
| | - Martin Dufva
- Department of Health Technology DTU Health Tech Technical University of Denmark Lyngby 2800 Kgs. Denmark
| | - Nazila Kamaly
- Department of Chemistry Molecular Sciences Research Hub (MSRH) Imperial College London London W12 0BZ UK
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8
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Bazban-Shotorbani S, Gavins F, Kant K, Dufva M, Kamaly N. A Biomicrofluidic Screening Platform for Dysfunctional Endothelium‐Targeted Nanoparticles and Therapeutics. Advanced NanoBiomed Research 2021. [DOI: 10.1002/anbr.202100092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Affiliation(s)
- Salime Bazban-Shotorbani
- Department of Health Technology DTU Health Tech Technical University of Denmark Lyngby 2800 Kgs. Denmark
- Department of Chemistry Molecular Sciences Research Hub (MSRH) Imperial College London London W12 0BZ UK
| | - Felicity Gavins
- Department of Life Sciences Centre for Inflammation Research and Translational Medicine (CIRTM) Brunel University London London UB8 3PH UK
| | - Krishna Kant
- Department of Physical Chemistry Biomedical Research Center of Galicia (CINBIO) University of Vigo Vigo 36310 Spain
| | - Martin Dufva
- Department of Health Technology DTU Health Tech Technical University of Denmark Lyngby 2800 Kgs. Denmark
| | - Nazila Kamaly
- Department of Chemistry Molecular Sciences Research Hub (MSRH) Imperial College London London W12 0BZ UK
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9
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Toppi A, Busk LL, Hu H, Dogan AA, Jönsson A, Taboryski RJ, Dufva M. Photolithographic Patterning of FluorAcryl for Biphilic Microwell-Based Digital Bioassays and Selection of Bacteria. ACS Appl Mater Interfaces 2021; 13:43914-43924. [PMID: 34491739 DOI: 10.1021/acsami.1c10096] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
FluorAcryl 3298 (FA) is a UV-curable fluoroacrylate polymer commonly employed as a chemically resistant, hydrophobic, and oleophobic coating. Here, FA was used in a cleanroom-based microstructuring process to fabricate hydrophilic-in-hydrophobic (HiH) micropatterned surfaces containing femtoliter-sized well arrays. A short protocol involving direct UV photopatterning, an etching step, and final recovery of the hydrophobic properties of the polymer produced patterned substrates with micrometer resolution. Specifically, HiH microwell arrays were obtained with a well diameter of 10 μm and various well depths ranging from 300 nm to 1 μm with high reproducibility. The 300 nm deep microdroplet array (MDA) substrates were used for digital immunoassays, which presented a limit of detection in the attomolar range. This demonstrated the chemical functionality of the hydrophilic and hydrophobic surfaces. Furthermore, the 1 μm deep wells could efficiently capture particles such as bacteria, whereas the 300 nm deep substrates or other types of flat HiH molecular monolayers could not. Capturing a mixture of bacteria expressing red- and green-fluorescent proteins, respectively, served as a model for screening and selection of specific phenotypes using FA-MDAs. Here, green-fluorescent bacteria were specifically selected by overlaying a solution of gelatin methacryloyl (GelMA) mixed with a photoinitiator and using a high-magnification objective, together with custom pinholes, in a common fluorescence microscope to cross-link the hydrogel around the bacteria of interest. In conclusion, due to the straightforward processing, versatility, and low-price, FA is an advantageous alternative to more commonly used fluorinated materials, such as CYTOP or Teflon-AF, for the fabrication of HiH microwell arrays and other biphilic microstructures.
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Affiliation(s)
- Arianna Toppi
- Department of Health Technology, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
| | - Louise L Busk
- Department of Health Technology, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
| | - Hongxia Hu
- Department of Health Technology, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
| | - Asli A Dogan
- Department of Health Technology, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
| | - Alexander Jönsson
- Department of Health Technology, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
| | - Rafael J Taboryski
- DTU Nanolab, National Centre for Nano Fabrication and Characterization, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
| | - Martin Dufva
- Department of Health Technology, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
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10
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Rizk J, Agerholm R, Jönsson A, Dogan AA, Dufva M, Bekiaris V. cIAP1/2 antagonization by SMAC mimetic induces non-canonical NF-κB mediated T H 17 cell homotypic interactions and increases their resistance to shear stress. Eur J Immunol 2021; 51:2097-2099. [PMID: 33960415 DOI: 10.1002/eji.202048983] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Revised: 04/22/2021] [Accepted: 05/05/2021] [Indexed: 11/09/2022]
Abstract
SMAC antagonization of cIAP1/2 in TH 17 cells upregulates cell adhesion and cytoskeleton genes through the NIK-RelB and p52 axis. SMAC also increases the homotypic interactions of TH 17 cells through a non-canonical NF-κB- and integrin-mediated mechanism resulting in increased ability of TH 17 cells to withstand shear stress.
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Affiliation(s)
- John Rizk
- Department of Health Technology, Technical University of Denmark, Lyngby, Denmark
| | - Rasmus Agerholm
- Department of Health Technology, Technical University of Denmark, Lyngby, Denmark
| | - Alexander Jönsson
- Department of Health Technology, Technical University of Denmark, Lyngby, Denmark
| | - Asli Aybike Dogan
- Department of Health Technology, Technical University of Denmark, Lyngby, Denmark
| | - Martin Dufva
- Department of Health Technology, Technical University of Denmark, Lyngby, Denmark
| | - Vasileios Bekiaris
- Department of Health Technology, Technical University of Denmark, Lyngby, Denmark
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11
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Lynagh T, Kiontke S, Meyhoff-Madsen M, Gless BH, Johannesen J, Kattelmann S, Christiansen A, Dufva M, Laustsen AH, Devkota K, Olsen CA, Kümmel D, Pless SA, Lohse B. Peptide Inhibitors of the α-Cobratoxin-Nicotinic Acetylcholine Receptor Interaction. J Med Chem 2020; 63:13709-13718. [PMID: 33143415 PMCID: PMC7705965 DOI: 10.1021/acs.jmedchem.0c01202] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
![]()
Venomous snakebites cause >100
000 deaths every year, in many cases
via potent depression of human neuromuscular signaling by snake α-neurotoxins.
Emergency therapy still relies on antibody-based antivenom, hampered
by poor access, frequent adverse reactions, and cumbersome production/purification.
Combining high-throughput discovery and subsequent structure–function
characterization, we present simple peptides that bind α-cobratoxin
(α-Cbtx) and prevent its inhibition of nicotinic acetylcholine
receptors (nAChRs) as a lead for the development of alternative antivenoms.
Candidate peptides were identified by phage display and deep sequencing,
and hits were characterized by electrophysiological recordings, leading
to an 8-mer peptide that prevented α-Cbtx inhibition of nAChRs.
We also solved the peptide:α-Cbtx cocrystal structure, revealing
that the peptide, although of unique primary sequence, binds to α-Cbtx
by mimicking structural features of the nAChR binding pocket. This
demonstrates the potential of small peptides to neutralize lethal
snake toxins in vitro, establishing a potential route to simple, synthetic,
low-cost antivenoms.
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Affiliation(s)
- Timothy Lynagh
- Sars International Centre for Marine Molecular Biology, University of Bergen, Thormøhlensgate 55, 5008 Bergen, Norway.,Center for Biopharmaceuticals & Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Stephan Kiontke
- Division of Structural Biology, Department of Biology/Chemistry, University of Osnabrück, Barbarastraße 13, Osnabrück 49076, Germany.,Faculty of Biology, Department of Plant Physiology and Photobiology, Philipps-Universität Marburg, Karl-von-Frisch-Straße 8, 35032 Marburg, Germany
| | - Maria Meyhoff-Madsen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Bengt H Gless
- Center for Biopharmaceuticals & Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Jónas Johannesen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Sabrina Kattelmann
- Institute of Biochemistry, University of Münster, Corrensstraße 36, 48149 Münster, Germany
| | - Anders Christiansen
- Fluid Array Systems and Technology, Nano and Bio-physical Systems, Department of Health Technology, Technical University of Denmark, Building 423 Produktionstorvet, DK-2800 Kongens Lyngby, Denmark
| | - Martin Dufva
- Fluid Array Systems and Technology, Nano and Bio-physical Systems, Department of Health Technology, Technical University of Denmark, Building 423 Produktionstorvet, DK-2800 Kongens Lyngby, Denmark
| | - Andreas H Laustsen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Kanchan Devkota
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Christian A Olsen
- Center for Biopharmaceuticals & Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Daniel Kümmel
- Division of Structural Biology, Department of Biology/Chemistry, University of Osnabrück, Barbarastraße 13, Osnabrück 49076, Germany.,Institute of Biochemistry, University of Münster, Corrensstraße 36, 48149 Münster, Germany
| | - Stephan Alexander Pless
- Center for Biopharmaceuticals & Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Brian Lohse
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
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12
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Jönsson A, Toppi A, Dufva M. The FAST Pump, a low-cost, easy to fabricate, SLA-3D-printed peristaltic pump for multi-channel systems in any lab. HardwareX 2020; 8:e00115. [PMID: 35498250 PMCID: PMC9041223 DOI: 10.1016/j.ohx.2020.e00115] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 04/15/2020] [Accepted: 06/04/2020] [Indexed: 05/09/2023]
Abstract
With the increasing interest in high throughput screening and parallel assays, laboratories around the world inevitably find themselves in need of driving a multitude of fluid lines to facilitate their large scale studies. The comparatively low cost and no-fluid-contact design of peristaltic pumps make them the go-to systems for such ventures, but using commercially available pumping systems this still becomes a costly endeavor at typically $250-$1000 per pump line. Here we have developed an alternative, a peristaltic pump that can be fabricated in most research laboratories using 3D-printing and readily available off-the-shelf parts. The pump features 8 parallel channels with linear ranges spanning from 0.7 µL/min to 6 mL/min. The pump can be fabricated and assembled by anyone with access to a 3D-printer at a cost of less than $45 per channel and is driven by a stepper motor that connects directly to any computer. This device has the potential to be disruptive in areas such as drug screening and assay development, as well as lab-on-a-chip applications and cell cultivation, where it significantly reduces hardware expenses and allows for construction of more comprehensive fluidic systems at a fraction of current costs.
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13
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Jensen JH, Cakal SD, Li J, Pless CJ, Radeke C, Jepsen ML, Jensen TE, Dufva M, Lind JU. Large-scale spontaneous self-organization and maturation of skeletal muscle tissues on ultra-compliant gelatin hydrogel substrates. Sci Rep 2020; 10:13305. [PMID: 32764726 PMCID: PMC7411013 DOI: 10.1038/s41598-020-69936-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2020] [Accepted: 07/15/2020] [Indexed: 11/09/2022] Open
Abstract
Cellular self-organization is the fundamental driving force behind the complex architectures of native tissue. Yet, attempts at replicating native tissue architectures in vitro often involve complex micro-fabrication methods and materials. While impressive progress has been made within engineered models of striated muscle, the wide adaptation of these models is held back by the need for specific tools and knowhow. In this report, we show that C2C12 myoblasts spontaneously organize into highly aligned myotube tissues on the mm to cm scale, when cultured on sufficiently soft yet fully isotropic gelatin hydrogel substrates. Interestingly, we only observed this phenomenon for hydrogels with Young’s modulus of 6 kPa and below. For slightly more rigid compositions, only local micrometer-scale myotube organization was observed, similar to that seen in conventional polystyrene dishes. The hydrogel-supported myotubes could be cultured for multiple weeks and matured into highly contractile phenotypes with notable upregulation of myosin heavy chain, as compared to myotubes developed in conventional petri dishes. The procedure for casting the ultra-soft gelatin hydrogels is straight forward and compatible with standardized laboratory tools. It may thus serve as a simple, yet versatile, approach to generating skeletal muscle tissue of improved physiological relevance for applied and basic research.
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Affiliation(s)
- Joen H Jensen
- Department of Health Technology, Technical University of Denmark, Building 423, 2800, Kgs. Lyngby, Denmark
| | - Selgin D Cakal
- Department of Health Technology, Technical University of Denmark, Building 423, 2800, Kgs. Lyngby, Denmark
| | - Jingwen Li
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, 2100, København Ø, Denmark
| | - Christian J Pless
- Department of Health Technology, Technical University of Denmark, Building 423, 2800, Kgs. Lyngby, Denmark
| | - Carmen Radeke
- Department of Health Technology, Technical University of Denmark, Building 423, 2800, Kgs. Lyngby, Denmark
| | - Morten Leth Jepsen
- Department of Health Technology, Technical University of Denmark, Building 423, 2800, Kgs. Lyngby, Denmark.,The Danish National Research Foundation and Villum Foundation's Center for Intelligent Drug Delivery and Sensing Using Microcontainers and Nanomechanics (IDUN), Technical University of Denmark, Building 423, 2800, Kgs. Lyngby, Denmark
| | - Thomas E Jensen
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, 2100, København Ø, Denmark
| | - Martin Dufva
- Department of Health Technology, Technical University of Denmark, Building 423, 2800, Kgs. Lyngby, Denmark. .,The Danish National Research Foundation and Villum Foundation's Center for Intelligent Drug Delivery and Sensing Using Microcontainers and Nanomechanics (IDUN), Technical University of Denmark, Building 423, 2800, Kgs. Lyngby, Denmark.
| | - Johan U Lind
- Department of Health Technology, Technical University of Denmark, Building 423, 2800, Kgs. Lyngby, Denmark.
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14
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Tian B, Gao F, Fock J, Dufva M, Hansen MF. Homogeneous circle-to-circle amplification for real-time optomagnetic detection of SARS-CoV-2 RdRp coding sequence. Biosens Bioelectron 2020; 165:112356. [PMID: 32510339 DOI: 10.1016/j.bios.2020.112356] [Citation(s) in RCA: 96] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 05/28/2020] [Accepted: 06/01/2020] [Indexed: 12/21/2022]
Abstract
Circle-to-circle amplification (C2CA) is a specific and precise cascade nucleic acid amplification method consisting of more than one round of padlock probe ligation and rolling circle amplification (RCA). Although C2CA provides a high amplification efficiency with a negligible increase of false-positive risk, it contains several step-by-step operation processes. We herein demonstrate a homogeneous and isothermal nucleic acid quantification strategy based on C2CA and optomagnetic analysis of magnetic nanoparticle (MNP) assembly. The proposed homogeneous circle-to-circle amplification eliminates the need for additional monomerization and ligation steps after the first round of RCA, and combines two amplification rounds in a one-pot reaction. The second round of RCA produces amplicon coils that anneal to detection probes grafted onto MNPs, resulting in MNP assembly that can be detected in real-time using an optomagnetic sensor. The proposed methodology was applied for the detection of a synthetic complementary DNA of SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2, also known as 2019-nCoV) RdRp (RNA-dependent RNA polymerase) coding sequence, achieving a detection limit of 0.4 fM with a dynamic detection range of 3 orders of magnitude and a total assay time of ca. 100 min. A mathematical model was set up and validated to predict the assay performance. Moreover, the proposed method was specific to distinguish SARS-CoV and SARS-CoV-2 sequences with high similarity.
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Affiliation(s)
- Bo Tian
- Department of Health Technology, Technical University of Denmark, DTU Health Tech, Building 345C, DK-2800, Kongens Lyngby, Denmark.
| | - Fei Gao
- Department of Physics, Technical University of Denmark, DTU Physics, Building 307, DK-2800, Kongens Lyngby, Denmark
| | - Jeppe Fock
- Blusense Diagnostics ApS, Fruebjergvej 3, DK-2100, Copenhagen, Denmark
| | - Martin Dufva
- Department of Health Technology, Technical University of Denmark, DTU Health Tech, Building 345C, DK-2800, Kongens Lyngby, Denmark
| | - Mikkel Fougt Hansen
- Department of Health Technology, Technical University of Denmark, DTU Health Tech, Building 345C, DK-2800, Kongens Lyngby, Denmark.
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15
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Leth Jepsen M, Willumsen A, Mazzoni C, Boisen A, Hagner Nielsen L, Dufva M. 3D Printed Stackable Titer Plate Inserts Supporting Three Interconnected Tissue Models for Drug Transport Studies. ACTA ACUST UNITED AC 2020; 4:e1900289. [DOI: 10.1002/adbi.201900289] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 03/17/2020] [Indexed: 01/06/2023]
Affiliation(s)
- Morten Leth Jepsen
- The Danish National Research Foundation and Villum Foundation’s Center for Intelligent Drug Delivery and Sensing Using Microcontainers and Nanomechanics (IDUN)Department of Health TechnologyTechnical University of Denmark Ørsteds Plads 345C Kgs. Lyngby 2800 Denmark
| | - Andreas Willumsen
- The Danish National Research Foundation and Villum Foundation’s Center for Intelligent Drug Delivery and Sensing Using Microcontainers and Nanomechanics (IDUN)Department of Health TechnologyTechnical University of Denmark Ørsteds Plads 345C Kgs. Lyngby 2800 Denmark
| | - Chiara Mazzoni
- The Danish National Research Foundation and Villum Foundation’s Center for Intelligent Drug Delivery and Sensing Using Microcontainers and Nanomechanics (IDUN)Department of Health TechnologyTechnical University of Denmark Ørsteds Plads 345C Kgs. Lyngby 2800 Denmark
| | - Anja Boisen
- The Danish National Research Foundation and Villum Foundation’s Center for Intelligent Drug Delivery and Sensing Using Microcontainers and Nanomechanics (IDUN)Department of Health TechnologyTechnical University of Denmark Ørsteds Plads 345C Kgs. Lyngby 2800 Denmark
| | - Line Hagner Nielsen
- The Danish National Research Foundation and Villum Foundation’s Center for Intelligent Drug Delivery and Sensing Using Microcontainers and Nanomechanics (IDUN)Department of Health TechnologyTechnical University of Denmark Ørsteds Plads 345C Kgs. Lyngby 2800 Denmark
| | - Martin Dufva
- The Danish National Research Foundation and Villum Foundation’s Center for Intelligent Drug Delivery and Sensing Using Microcontainers and Nanomechanics (IDUN)Department of Health TechnologyTechnical University of Denmark Ørsteds Plads 345C Kgs. Lyngby 2800 Denmark
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16
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Tian B, Minero G, Fock J, Dufva M, Hansen MF. CRISPR-Cas12a based internal negative control for nonspecific products of exponential rolling circle amplification. Nucleic Acids Res 2020; 48:e30. [PMID: 31956898 PMCID: PMC7049689 DOI: 10.1093/nar/gkaa017] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 12/16/2019] [Accepted: 01/03/2020] [Indexed: 12/26/2022] Open
Abstract
False-positive results cause a major problem in nucleic acid amplification, and require external blank/negative controls for every test. However, external controls usually have a simpler and lower background compared to the test sample, resulting in underestimation of false-positive risks. Internal negative controls, performed simultaneously with amplification to monitor the background level in real-time, are therefore appealing in both research and clinic. Herein, we describe a nonspecific product-activated single-stranded DNA-cutting approach based on CRISPR (clustered regularly interspaced short palindromic repeats) Cas12a (Cpf1) nuclease. The proposed approach, termed Cas12a-based internal referential indicator (CIRI), can indicate the onset of nonspecific amplification in an exponential rolling circle amplification strategy here combined with an optomagnetic readout. The capability of CIRI as an internal negative control can potentially be extended to other amplification strategies and sensors, improving the performance of nucleic acid amplification-based methodologies.
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Affiliation(s)
- Bo Tian
- Department of Health Technology, Technical University of Denmark, DTU Health Tech, Building 345C, DK-2800 Kongens Lyngby, Denmark
| | - Gabriel Antonio S Minero
- Department of Health Technology, Technical University of Denmark, DTU Health Tech, Building 345C, DK-2800 Kongens Lyngby, Denmark
| | - Jeppe Fock
- Blusense Diagnostics ApS, Fruebjergvej 3, DK-2100 Copenhagen, Denmark
| | - Martin Dufva
- Department of Health Technology, Technical University of Denmark, DTU Health Tech, Building 345C, DK-2800 Kongens Lyngby, Denmark
| | - Mikkel Fougt Hansen
- Department of Health Technology, Technical University of Denmark, DTU Health Tech, Building 345C, DK-2800 Kongens Lyngby, Denmark
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17
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Chen J, Vestergaard M, Shen J, Solem C, Dufva M, Jensen PR. Droplet-based microfluidics as a future tool for strain improvement in lactic acid bacteria. FEMS Microbiol Lett 2019. [DOI: 10.1093/femsle/fny258s] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
ABSTRACTStrain development is frequently used to improve the performance and functionality of industrially important microbes. As traditional mutagenesis screen is especially utilized by the food industry to improve strains used in food fermentation, high-throughput and cost-effective screening tools are important in mutant selection. The emerging droplet-based microfluidics technology miniaturizes the volume for cell cultivation and phenotype interrogation down to the picoliter scales, which facilitates screening of microbes for improved phenotypical properties tremendously. In this mini review, we present recent application of the droplet-based microfluidics in microbial strain improvement with a focus on its potential use in the screening of lactic acid bacteria.
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Affiliation(s)
- Jun Chen
- National Food Institute, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - Mike Vestergaard
- National Food Institute, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - Jing Shen
- National Food Institute, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - Christian Solem
- National Food Institute, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - Martin Dufva
- Department of Micro- and Nanotechnology, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - Peter Ruhdal Jensen
- National Food Institute, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
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18
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Chen J, Vestergaard M, Shen J, Solem C, Dufva M, Jensen PR. Droplet-based microfluidics as a future tool for strain improvement in lactic acid bacteria. FEMS Microbiol Lett 2019; 365:5144213. [PMID: 30357328 DOI: 10.1093/femsle/fny258] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 10/23/2018] [Indexed: 11/13/2022] Open
Abstract
Strain development is frequently used to improve the performance and functionality of industrially important microbes. As traditional mutagenesis screen is especially utilized by the food industry to improve strains used in food fermentation, high-throughput and cost-effective screening tools are important in mutant selection. The emerging droplet-based microfluidics technology miniaturizes the volume for cell cultivation and phenotype interrogation down to the picoliter scales, which facilitates screening of microbes for improved phenotypical properties tremendously. In this mini review, we present recent application of the droplet-based microfluidics in microbial strain improvement with a focus on its potential use in the screening of lactic acid bacteria.
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Affiliation(s)
- Jun Chen
- National Food Institute, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - Mike Vestergaard
- National Food Institute, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - Jing Shen
- National Food Institute, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - Christian Solem
- National Food Institute, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - Martin Dufva
- Department of Micro- and Nanotechnology, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - Peter Ruhdal Jensen
- National Food Institute, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
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19
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Ramadan Q, Alberti M, Dufva M, Tung YC. Editorial: Medical and Industrial Applications of Microfluidic-Based Cell/Tissue Culture and Organs-on-a-Chip. Front Bioeng Biotechnol 2019; 7:151. [PMID: 31294020 PMCID: PMC6606690 DOI: 10.3389/fbioe.2019.00151] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Accepted: 06/10/2019] [Indexed: 11/13/2022] Open
Affiliation(s)
- Qasem Ramadan
- Agency for Science, Technology and Research (ASTAR), Singapore, Singapore
| | - Massimo Alberti
- Agency for Science, Technology and Research (ASTAR), Singapore, Singapore
| | - Martin Dufva
- Department of Health Technology, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Yi-Chung Tung
- Research Center for Applied Sciences, Academia Sinica, Taipei, Taiwan
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20
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Jepsen ML, Nielsen LH, Boisen A, Almdal K, Dufva M. Characterization of thin gelatin hydrogel membranes with balloon properties for dynamic tissue engineering. Biopolymers 2018; 110:e23241. [PMID: 30536858 DOI: 10.1002/bip.23241] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 10/12/2018] [Accepted: 11/02/2018] [Indexed: 02/04/2023]
Abstract
Cell or tissue stretching and strain are present in any in vivo environment, but is difficult to reproduce in vitro. Here, we describe a simple method for casting a thin (about 500 μm) and soft (about 0.3 kPa) hydrogel of gelatin and a method for characterizing the mechanical properties of the hydrogel simply by changing pressure with a water column. The gelatin is crosslinked with mTransglutaminase and the area of the resulting hydrogel can be increased up 13-fold by increasing the radial water pressure. This is far beyond physiological stretches observed in vivo. Actuating the hydrogel with a radial force achieves both information about stiffness, stretchability, and contractability, which are relevant properties for tissue engineering purposes. Cells could be stretched and contracted using the gelatin membrane. Gelatin is a commonly used polymer for hydrogels in tissue engineering, and the discovered reversible stretching is particularly interesting for organ modeling applications.
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Affiliation(s)
- Morten Leth Jepsen
- Department of Micro- and Nanotechnology, The Danish National Research Foundation and Villum Foundation's Center for Intelligent Drug Delivery and Sensing Using Microcontainers and Nanomechanics (IDUN), Technical University of Denmark, Kongens Lyngby, Denmark
| | - Line Hagner Nielsen
- Department of Micro- and Nanotechnology, The Danish National Research Foundation and Villum Foundation's Center for Intelligent Drug Delivery and Sensing Using Microcontainers and Nanomechanics (IDUN), Technical University of Denmark, Kongens Lyngby, Denmark
| | - Anja Boisen
- Department of Micro- and Nanotechnology, The Danish National Research Foundation and Villum Foundation's Center for Intelligent Drug Delivery and Sensing Using Microcontainers and Nanomechanics (IDUN), Technical University of Denmark, Kongens Lyngby, Denmark
| | - Kristoffer Almdal
- Department of Micro- and Nanotechnology, The Danish National Research Foundation and Villum Foundation's Center for Intelligent Drug Delivery and Sensing Using Microcontainers and Nanomechanics (IDUN), Technical University of Denmark, Kongens Lyngby, Denmark
| | - Martin Dufva
- Department of Micro- and Nanotechnology, The Danish National Research Foundation and Villum Foundation's Center for Intelligent Drug Delivery and Sensing Using Microcontainers and Nanomechanics (IDUN), Technical University of Denmark, Kongens Lyngby, Denmark
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21
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Kunding AH, Busk LL, Webb H, Klafki HW, Otto M, Kutter JP, Dufva M. Micro-droplet arrays for micro-compartmentalization using an air/water interface. Lab Chip 2018; 18:2797-2805. [PMID: 30123911 DOI: 10.1039/c8lc00608c] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Here we present a water-in-air droplet platform for micro-compartmentalization for single molecule guided synthesis and analysis consisting of a flow-system hosting dense arrays of aqueous microdroplets on a glass surface surrounded by air. The droplets are formed in a few seconds by passing a waterfront over the array of hydrophilic spots surrounded by a hydrophobic coating, thus forming a micro-droplet array (MDA). The droplet volumes are tunable from approximately 50 femtoliter to 20 picoliter by adjusting the size of the hydrophilic spots. MDAs consisting of femtoliter volume droplets were stable for more than 24 hours in air at 37 °C in a reversibly sealed flow-system, thus allowing us to perform assays that require long incubations in the droplets. Using differently fluorescing liquids, it was further shown that droplets can be reformed on the same MDA several times by passing a new liquid plug over the surface, and that fluorescence from one reaction can be washed away with little to no carry-over, hence allowing for multistep reactions to be carried out on the system. The MDA created by an air/water interface supported digital immunoassays as was demonstrated by measuring the Aβ42 peptide in cerebrospinal fluid of Alzheimers patients and control patients. To demonstrate a two step droplet assay, first, histidine tagged peptides were expressed in the droplets and bound to the droplet-enclosed surface. Subsequently, the his-tagged peptides were detected using enzyme-conjugated antibodies in a second droplet generation step. As such, the chip demonstrates features necessary for library preparations for high throughput screening applications.
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Affiliation(s)
- Andreas H Kunding
- Dept. of research & development, SELMA Diagnostics ApS, Copenhagen Bio-Science Park, 2200 Copenhagen, Denmark
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22
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Tan HY, Trier S, Rahbek UL, Dufva M, Kutter JP, Andresen TL. A multi-chamber microfluidic intestinal barrier model using Caco-2 cells for drug transport studies. PLoS One 2018; 13:e0197101. [PMID: 29746551 PMCID: PMC5944968 DOI: 10.1371/journal.pone.0197101] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Accepted: 04/26/2018] [Indexed: 01/13/2023] Open
Abstract
This paper presents the design and fabrication of a multi-layer and multi-chamber microchip system using thiol-ene ‘click chemistry’ aimed for drug transport studies across tissue barrier models. The fabrication process enables rapid prototyping of multi-layer microfluidic chips using different thiol-ene polymer mixtures, where porous Teflon membranes for cell monolayer growth were incorporated by masked sandwiching thiol-ene-based fluid layers. Electrodes for trans-epithelial electrical resistance (TEER) measurements were incorporated using low-melting soldering wires in combination with platinum wires, enabling parallel real-time monitoring of barrier integrity for the eight chambers. Additionally, the translucent porous Teflon membrane enabled optical monitoring of cell monolayers. The device was developed and tested with the Caco-2 intestinal model, and compared to the conventional Transwell system. Cell monolayer differentiation was assessed via in situ immunocytochemistry of tight junction and mucus proteins, P-glycoprotein 1 (P-gp) mediated efflux of Rhodamine 123, and brush border aminopeptidase activity. Monolayer tightness and relevance for drug delivery research was evaluated through permeability studies of mannitol, dextran and insulin, alone or in combination with the absorption enhancer tetradecylmaltoside (TDM). The thiol-ene-based microchip material and electrodes were highly compatible with cell growth. In fact, Caco-2 cells cultured in the device displayed differentiation, mucus production, directional transport and aminopeptidase activity within 9–10 days of cell culture, indicating robust barrier formation at a faster rate than in conventional Transwell models. The cell monolayer displayed high TEER and tightness towards hydrophilic compounds, whereas co-administration of an absorption enhancer elicited TEER-decrease and increased permeability similar to the Transwell cultures. The presented cell barrier microdevice constitutes a relevant tissue barrier model, enabling transport studies of drugs and chemicals under real-time optical and functional monitoring in eight parallel chambers, thereby increasing the throughput compared to previously reported microdevices.
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Affiliation(s)
- Hsih-Yin Tan
- Technical University of Denmark, Department of Micro and Nanotechnology, Ørsteds Plads, Lyngby, Denmark
- Technical University of Denmark, Center for Nanomedicine and Theranostics, Ørsteds Plads, Lyngby, Denmark
- Biomedical Institute for Global Health Research & Technology (BIGHEART), National University of Singapore, Singapore
| | - Sofie Trier
- Global Research, Novo Nordisk A/S, Maaloev, Denmark
| | | | - Martin Dufva
- Technical University of Denmark, Department of Micro and Nanotechnology, Ørsteds Plads, Lyngby, Denmark
- * E-mail:
| | - Jörg P. Kutter
- Department of Pharmacy, University of Copenhagen, Universitetsparken 2, Copenhagen, Denmark
| | - Thomas L. Andresen
- Technical University of Denmark, Department of Micro and Nanotechnology, Ørsteds Plads, Lyngby, Denmark
- Technical University of Denmark, Center for Nanomedicine and Theranostics, Ørsteds Plads, Lyngby, Denmark
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23
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Starokozhko V, Hemmingsen M, Larsen L, Mohanty S, Merema M, Pimentel RC, Wolff A, Emnéus J, Aspegren A, Groothuis G, Dufva M. Differentiation of human-induced pluripotent stem cell under flow conditions to mature hepatocytes for liver tissue engineering. J Tissue Eng Regen Med 2018; 12:1273-1284. [PMID: 29499107 PMCID: PMC5969064 DOI: 10.1002/term.2659] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Revised: 01/30/2018] [Accepted: 02/17/2018] [Indexed: 12/27/2022]
Abstract
Hepatic differentiation of human-induced pluripotent stem cells (hiPSCs) under flow conditions in a 3D scaffold is expected to be a major step forward for construction of bioartificial livers. The aims of this study were to induce hepatic differentiation of hiPSCs under perfusion conditions and to perform functional comparisons with fresh human precision-cut liver slices (hPCLS), an excellent benchmark for the human liver in vivo. The majority of the mRNA expression of CYP isoenzymes and transporters and the tested CYP activities, Phase II metabolism, and albumin, urea, and bile acid synthesis in the hiPSC-derived cells reached values that overlap those of hPCLS, which indicates a higher degree of hepatic differentiation than observed until now. Differentiation under flow compared with static conditions had a strong inducing effect on Phase II metabolism and suppressed AFP expression but resulted in slightly lower activity of some of the Phase I metabolism enzymes. Gene expression data indicate that hiPSCs differentiated into both hepatic and biliary directions. In conclusion, the hiPSC differentiated under flow conditions towards hepatocytes express a wide spectrum of liver functions at levels comparable with hPCLS indicating excellent future perspectives for the development of a bioartificial liver system for toxicity testing or as liver support device for patients.
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Affiliation(s)
- Viktoriia Starokozhko
- Groningen Research Institute for PharmacyUniversity of GroningenGroningenThe Netherlands
| | - Mette Hemmingsen
- Department of Micro‐ and NanotechnologyTechnical University of DenmarkDenmark
| | - Layla Larsen
- Department of Micro‐ and NanotechnologyTechnical University of DenmarkDenmark
| | | | - Marjolijn Merema
- Groningen Research Institute for PharmacyUniversity of GroningenGroningenThe Netherlands
| | - Rodrigo C. Pimentel
- Department of Micro‐ and NanotechnologyTechnical University of DenmarkDenmark
| | - Anders Wolff
- Department of Micro‐ and NanotechnologyTechnical University of DenmarkDenmark
| | - Jenny Emnéus
- Department of Micro‐ and NanotechnologyTechnical University of DenmarkDenmark
| | | | - Geny Groothuis
- Groningen Research Institute for PharmacyUniversity of GroningenGroningenThe Netherlands
| | - Martin Dufva
- Department of Micro‐ and NanotechnologyTechnical University of DenmarkDenmark
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24
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Pimentel C R, Ko SK, Caviglia C, Wolff A, Emnéus J, Keller SS, Dufva M. Three-dimensional fabrication of thick and densely populated soft constructs with complex and actively perfused channel network. Acta Biomater 2018; 65:174-184. [PMID: 29102798 DOI: 10.1016/j.actbio.2017.10.047] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 10/16/2017] [Accepted: 10/31/2017] [Indexed: 01/08/2023]
Abstract
One of the fundamental steps needed to design functional tissues and, ultimately organs is the ability to fabricate thick and densely populated tissue constructs with controlled vasculature and microenvironment. To date, bioprinting methods have been employed to manufacture tissue constructs with open vasculature in a square-lattice geometry, where the majority lacks the ability to be directly perfused. Moreover, it appears to be difficult to fabricate vascular tissue constructs targeting the stiffness of soft tissues such as the liver. Here we present a method for the fabrication of thick (e.g. 1 cm) and densely populated (e.g. 10 million cells·mL-1) tissue constructs with a three-dimensional (3D) four arm branch network and stiffness in the range of soft tissues (1-10 kPa), which can be directly perfused on a fluidic platform for long time periods (>14 days). Specifically, we co-print a 3D four-arm branch using water-soluble Poly(vinyl alcohol) (PVA) as main material and Poly(lactic acid) (PLA) as the support structure. The PLA support structure was selectively removed, and the water soluble PVA structure was used for creating a 3D vascular network within a customized extracellular matrix (ECM) targeting the stiffness of the liver and with encapsulated hepatocellular carcinoma (HepG2) cells. These constructs were directly perfused with medium inducing the proliferation of HepG2 cells and the formation of spheroids. The highest spheroid density was obtained with perfusion, but overall the tissue construct displayed two distinct zones, one of rapid proliferation and one with almost no cell division and high cell death. The created model, therefore, simulate gradients in tissues of necrotic regions in tumors. This versatile method could represent a fundamental step in the fabrication of large functional and complex tissues and finally organs. STATEMENT OF SIGNIFICANCE Vascularization within hydrogels with mechanical properties in the range of soft tissues remains a challenge. To date, bioprinting have been employed to manufacture tissue constructs with open vasculature in a square-lattice geometry that are most of the time not perfused. This study shows the creation of densely populated tissue constructs with a 3D four arm branch network and stiffness in the range of soft tissues, which can be directly perfused. The cells encapsulated within the construct showed proliferation as a function of the vasculature distance, and the control of the micro-environment induced the encapsulated cells to aggregate in spheroids in specific positions. This method could be used for modeling tumors and for fabricating more complex and densely populated tissue constructs with translational potential.
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Affiliation(s)
- Rodrigo Pimentel C
- Department of Micro- and Nanotechnology, Technical University of Denmark, Denmark
| | - Suk Kyu Ko
- Department of Micro- and Nanotechnology, Technical University of Denmark, Denmark
| | - Claudia Caviglia
- Department of Micro- and Nanotechnology, Technical University of Denmark, Denmark
| | - Anders Wolff
- Department of Micro- and Nanotechnology, Technical University of Denmark, Denmark
| | - Jenny Emnéus
- Department of Micro- and Nanotechnology, Technical University of Denmark, Denmark
| | | | - Martin Dufva
- Department of Micro- and Nanotechnology, Technical University of Denmark, Denmark.
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25
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Rizzi G, Lee JR, Dahl C, Guldberg P, Dufva M, Wang SX, Hansen MF. Simultaneous Profiling of DNA Mutation and Methylation by Melting Analysis Using Magnetoresistive Biosensor Array. ACS Nano 2017; 11:8864-8870. [PMID: 28832112 PMCID: PMC5810360 DOI: 10.1021/acsnano.7b03053] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Epigenetic modifications, in particular DNA methylation, are gaining increasing interest as complementary information to DNA mutations for cancer diagnostics and prognostics. We introduce a method to simultaneously profile DNA mutation and methylation events for an array of sites with single site specificity. Genomic (mutation) or bisulphite-treated (methylation) DNA is amplified using nondiscriminatory primers, and the amplicons are then hybridized to a giant magnetoresistive (GMR) biosensor array followed by melting curve measurements. The GMR biosensor platform offers scalable multiplexed detection of DNA hybridization, which is insensitive to temperature variation. The melting curve approach further enhances the assay specificity and tolerance to variations in probe length. We demonstrate the utility of this method by simultaneously profiling five mutation and four methylation sites in human melanoma cell lines. The method correctly identified all mutation and methylation events and further provided quantitative assessment of methylation density validated by bisulphite pyrosequencing.
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Affiliation(s)
- Giovanni Rizzi
- Department of Micro- and Nanotechnology DTU Nanotech, Technical University of Denmark, Building 345B, Kongens Lyngby, DK 2800, Denmark
| | - Jung-Rok Lee
- Division of Mechanical and Biomedical Engineering, ELTEC College of Engineering, Ewha Womans University, Seoul 03760, South Korea
- Department of Materials Science and Engineering, Stanford University, Stanford, California 93405, United States
| | - Christina Dahl
- Danish Cancer Society Research Center, Copenhagen, DK 2100, Denmark
| | - Per Guldberg
- Danish Cancer Society Research Center, Copenhagen, DK 2100, Denmark
| | - Martin Dufva
- Department of Micro- and Nanotechnology DTU Nanotech, Technical University of Denmark, Building 345B, Kongens Lyngby, DK 2800, Denmark
| | - Shan X. Wang
- Department of Materials Science and Engineering, Stanford University, Stanford, California 93405, United States
- Department of Electrical Engineering, Stanford University, Stanford, California 93405, United States
- Corresponding Authors:.
| | - Mikkel F. Hansen
- Department of Micro- and Nanotechnology DTU Nanotech, Technical University of Denmark, Building 345B, Kongens Lyngby, DK 2800, Denmark
- Corresponding Authors:.
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26
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Rizzi G, Lee JR, Guldberg P, Dufva M, Wang SX, Hansen MF. Denaturation strategies for detection of double stranded PCR products on GMR magnetic biosensor array. Biosens Bioelectron 2017; 93:155-160. [DOI: 10.1016/j.bios.2016.09.031] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Revised: 09/08/2016] [Accepted: 09/10/2016] [Indexed: 01/08/2023]
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27
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Abstract
We present a microfluidic system and its use to measure DNA denaturation curves by varying the temperature or salt (Na+) concentration. The readout is based on real-time measurements of DNA hybridization using magnetoresistive sensors and magnetic nanoparticles (MNPs) as labels. We report the first melting curves of DNA hybrids measured as a function of continuously decreasing salt concentration at fixed temperature and compare them to the corresponding curves obtained vs. temperature at fixed salt concentration. The magnetoresistive sensor platform provided reliable results under varying temperature as well as salt concentration. The salt concentration melting curves were found to be more reliable than temperature melting curves. We performed a two-dimensional mapping of the melting profiles of a target to probes targeting its wild type (WT) and mutant type (MT) variants in the temperature-salt concentration plane. This map clearly showed a region of optimum ability to differentiate between the two variants. We finally demonstrated single nucleotide polymorphysm (SNP) genotyping using both denaturation methods on both separate sensors but also using a differential measurement on a single sensor. The results demonstrate that concentration melting provides an attractive alternative to temperature melting in on-chip DNA denaturation experiments and further show that the magnetoresistive platform is attractive due to its low cross-sensitivity to temperature and liquid composition.
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Affiliation(s)
- Giovanni Rizzi
- Department of Micro- and Nanotechnology, DTU Nanotech, Building 345B, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark.
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28
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Mark C, Zór K, Heiskanen A, Dufva M, Emnéus J, Finnie C. Monitoring intra- and extracellular redox capacity of intact barley aleurone layers responding to phytohormones. Anal Biochem 2016; 515:1-8. [PMID: 27641112 DOI: 10.1016/j.ab.2016.09.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Revised: 09/12/2016] [Accepted: 09/14/2016] [Indexed: 11/29/2022]
Abstract
Redox regulation is important for numerous processes in plant cells including abiotic stress, pathogen defence, tissue development, seed germination and programmed cell death. However, there are few methods allowing redox homeostasis to be addressed in whole plant cells, providing insight into the intact in vivo environment. An electrochemical redox assay that applies the menadione-ferricyanide double mediator is used to assess changes in the intracellular and extracellular redox environment in living aleurone layers of barley (Hordeum vulgare cv. Himalaya) grains, which respond to the phytohormones gibberellic acid and abscisic acid. Gibberellic acid is shown to elicit a mobilisation of electrons as detected by an increase in the reducing capacity of the aleurone layers. By taking advantage of the membrane-permeable menadione/menadiol redox pair to probe the membrane-impermeable ferricyanide/ferrocyanide redox pair, the mobilisation of electrons was dissected into an intracellular and an extracellular, plasma membrane-associated component. The intracellular and extracellular increases in reducing capacity were both suppressed when the aleurone layers were incubated with abscisic acid. By probing redox levels in intact plant tissue, the method provides a complementary approach to assays of reactive oxygen species and redox-related enzyme activities in tissue extracts.
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Affiliation(s)
- Christina Mark
- Agricultural and Environmental Proteomics, Department of Systems Biology, Technical University of Denmark, DK-2800 Kgs.Lyngby, Denmark
| | - Kinga Zór
- Bioanalytics, Department of Micro- and Nanotechnology, Technical University of Denmark, DK-2800 Kgs.Lyngby, Denmark
| | - Arto Heiskanen
- Bioanalytics, Department of Micro- and Nanotechnology, Technical University of Denmark, DK-2800 Kgs.Lyngby, Denmark
| | - Martin Dufva
- Fluidic Array Systems and Technology, Department of Micro- and Nanotechnology, Technical University of Denmark, DK-2800 Kgs.Lyngby, Denmark
| | - Jenny Emnéus
- Bioanalytics, Department of Micro- and Nanotechnology, Technical University of Denmark, DK-2800 Kgs.Lyngby, Denmark
| | - Christine Finnie
- Agricultural and Environmental Proteomics, Department of Systems Biology, Technical University of Denmark, DK-2800 Kgs.Lyngby, Denmark; Carlsberg Research Laboratory, J.C. Jacobsens Gade 4, DK-1799 Copenhagen V, Denmark.
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29
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Mohanty S, Alm M, Hemmingsen M, Dolatshahi-Pirouz A, Trifol J, Thomsen P, Dufva M, Wolff A, Emnéus J. 3D Printed Silicone–Hydrogel Scaffold with Enhanced Physicochemical Properties. Biomacromolecules 2016; 17:1321-9. [DOI: 10.1021/acs.biomac.5b01722] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Soumyaranjan Mohanty
- DTU
Nanotech, Department of Micro- and Nanotechnology, Technical University of Denmark, Ørsteds Plads, DK-2800 Kgs, Lyngby, Denmark
| | - Martin Alm
- BioModics ApS, Gregersensvej 7, DK-2630 Taastrup, Denmark
| | - Mette Hemmingsen
- DTU
Nanotech, Department of Micro- and Nanotechnology, Technical University of Denmark, Ørsteds Plads, DK-2800 Kgs, Lyngby, Denmark
| | - Alireza Dolatshahi-Pirouz
- DTU
Nanotech, Department of Micro- and Nanotechnology, Technical University of Denmark, Ørsteds Plads, DK-2800 Kgs, Lyngby, Denmark
- Technical
University of Denmark, DTU Nanotech, Center for Nanomedicine and Theranostics, 2800 Kgs, Denmark
| | - Jon Trifol
- Danish Polymer Centre, Department of Chemical and
Biochemical Engineering, Søltofts Plads, Building 229, DK-2800, Kgs, Lyngby, Denmark
| | - Peter Thomsen
- BioModics ApS, Gregersensvej 7, DK-2630 Taastrup, Denmark
| | - Martin Dufva
- DTU
Nanotech, Department of Micro- and Nanotechnology, Technical University of Denmark, Ørsteds Plads, DK-2800 Kgs, Lyngby, Denmark
| | - Anders Wolff
- DTU
Nanotech, Department of Micro- and Nanotechnology, Technical University of Denmark, Ørsteds Plads, DK-2800 Kgs, Lyngby, Denmark
| | - Jenny Emnéus
- DTU
Nanotech, Department of Micro- and Nanotechnology, Technical University of Denmark, Ørsteds Plads, DK-2800 Kgs, Lyngby, Denmark
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30
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Canali C, Mazzoni C, Larsen LB, Heiskanen A, Martinsen ØG, Wolff A, Dufva M, Emnéus J. An impedance method for spatial sensing of 3D cell constructs--towards applications in tissue engineering. Analyst 2016. [PMID: 26198701 DOI: 10.1039/c5an00987a] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
We present the characterisation and validation of multiplexed 4-terminal (4T) impedance measurements as a method for sensing the spatial location of cell aggregates within large three-dimensional (3D) gelatin scaffolds. The measurements were performed using an array of four rectangular chambers, each having eight platinum needle electrodes for parallel analysis. The electrode positions for current injection and voltage measurements were optimised by means of finite element simulations to maximise the sensitivity field distribution and spatial resolution. Eight different 4T combinations were experimentally tested in terms of the spatial sensitivity. The simulated sensitivity fields were validated using objects (phantoms) with different conductivity and size placed in different positions inside the chamber. This provided the detection limit (volume sensitivity) of 16.5%, i.e. the smallest detectable volume with respect to the size of the measurement chamber. Furthermore, the possibility for quick single frequency analysis was demonstrated by finding a common frequency of 250 kHz for all the presented electrode combinations. As final proof of concept, a high density of human hepatoblastoma (HepG2) cells were encapsulated in gelatin to form artificial 3D cell constructs and detected when placed in different positions inside large gelatin scaffolds. Taken together, these results open new perspectives for impedance-based sensing technologies for non-invasive monitoring in tissue engineering applications providing spatial information of constructs within biologically relevant 3D environments.
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Affiliation(s)
- C Canali
- Department of Micro- and Nanotechnology, Technical University of Denmark, 2800, Kgs. Lyngby, Denmark.
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31
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Rasmussen CH, Petersen DR, Moeller JB, Hansson M, Dufva M. Collagen Type I Improves the Differentiation of Human Embryonic Stem Cells towards Definitive Endoderm. PLoS One 2015; 10:e0145389. [PMID: 26713616 PMCID: PMC4694921 DOI: 10.1371/journal.pone.0145389] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Accepted: 12/03/2015] [Indexed: 12/16/2022] Open
Abstract
Human embryonic stem cells have the ability to generate all cell types in the body and can potentially provide an unlimited source of cells for cell replacement therapy to treat degenerative diseases such as diabetes. Current differentiation protocols of human embryonic stem cells towards insulin producing beta cells focus on soluble molecules whereas the impact of cell-matrix interactions has been mainly unattended. In this study almost 500 different extracellular matrix protein combinations were screened to systemically identify extracellular matrix proteins that influence differentiation of human embryonic stem cells to the definitive endoderm lineage. The percentage of definitive endoderm cells after differentiation on collagen I and fibronectin was >85% and 65%, respectively. The cells on collagen I substrates displayed different morphology and gene expression during differentiation as assessed by time lapse studies compared to cells on the other tested substrates. Global gene expression analysis showed that cells differentiated on collagen I were largely similar to cells on fibronectin after completed differentiation. Collectively, the data suggest that collagen I induces a more rapid and consistent differentiation of stem cells to definitive endoderm. The results shed light on the importance of extracellular matrix proteins for differentiation and also points to a cost effective and easy method to improve differentiation.
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Affiliation(s)
| | | | | | | | - Martin Dufva
- DTU Nanotech, Technical University of Denmark, Kgs. Lyngby, Denmark
- * E-mail: (MH); (MD)
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32
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Christiansen A, Kringelum JV, Hansen CS, Bøgh KL, Sullivan E, Patel J, Rigby NM, Eiwegger T, Szépfalusi Z, de Masi F, Nielsen M, Lund O, Dufva M. High-throughput sequencing enhanced phage display enables the identification of patient-specific epitope motifs in serum. Sci Rep 2015; 5:12913. [PMID: 26246327 PMCID: PMC4650709 DOI: 10.1038/srep12913] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Accepted: 07/08/2015] [Indexed: 12/13/2022] Open
Abstract
Phage display is a prominent screening technique with a multitude of applications including therapeutic antibody development and mapping of antigen epitopes. In this study, phages were selected based on their interaction with patient serum and exhaustively characterised by high-throughput sequencing. A bioinformatics approach was developed in order to identify peptide motifs of interest based on clustering and contrasting to control samples. Comparison of patient and control samples confirmed a major issue in phage display, namely the selection of unspecific peptides. The potential of the bioinformatic approach was demonstrated by identifying epitopes of a prominent peanut allergen, Ara h 1, in sera from patients with severe peanut allergy. The identified epitopes were confirmed by high-density peptide micro-arrays. The present study demonstrates that high-throughput sequencing can empower phage display by (i) enabling the analysis of complex biological samples, (ii) circumventing the traditional laborious picking and functional testing of individual phage clones and (iii) reducing the number of selection rounds.
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Affiliation(s)
- Anders Christiansen
- Department of Micro- and Nanotechnology, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Jens V Kringelum
- Center for Biological Sequence Analysis, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Christian S Hansen
- Center for Biological Sequence Analysis, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Katrine L Bøgh
- National Food Institute, Technical University of Denmark, Søborg, Denmark
| | - Eric Sullivan
- Roche NimbleGen, Madison, Wisconsin, the United States of America
| | - Jigar Patel
- Roche NimbleGen, Madison, Wisconsin, the United States of America
| | - Neil M Rigby
- Institute of Food Research, Norwich, United Kingdom
| | - Thomas Eiwegger
- Department of Paediatrics, Medical University of Vienna, Vienna, Austria
| | - Zsolt Szépfalusi
- Department of Paediatrics, Medical University of Vienna, Vienna, Austria
| | - Federico de Masi
- Center for Biological Sequence Analysis, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Morten Nielsen
- 1] Center for Biological Sequence Analysis, Technical University of Denmark, Kgs. Lyngby, Denmark [2] Instituto de Investigaciones Biotecnológicas, Universidad Nacional de San Martín, Buenos Aires, Argentina
| | - Ole Lund
- Center for Biological Sequence Analysis, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Martin Dufva
- Department of Micro- and Nanotechnology, Technical University of Denmark, Kgs. Lyngby, Denmark
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33
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Nunes PS, Kjaerulff S, Dufva M, Mogensen KB. Real-time direct cell concentration and viability determination using a fully automated microfluidic platform for standalone process monitoring. Analyst 2015; 140:4007-20. [PMID: 25923294 DOI: 10.1039/c5an00478k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The industrial production of cells has a large unmet need for greater process monitoring, in addition to the standard temperature, pH and oxygen concentration determination. Monitoring the cell health by a vast range of fluorescence cell-based assays can greatly improve the feedback control and thereby ensure optimal cell production, by prolonging the fermentation cycle and increasing the bioreactor output. In this work, we report on the development of a fully automated microfluidic system capable of extracting samples directly from a bioreactor, diluting the sample, staining the cells, and determining the total cell and dead cells concentrations, within a time frame of 10.3 min. The platform consists of custom made stepper motor actuated peristaltic pumps and valves, fluidic interconnections, sample to waste liquid management and image cytometry-based detection. The total concentration of cells is determined by brightfield microscopy, while fluorescence detection is used to detect propidium iodide stained non-viable cells. This method can be incorporated into facilities with bioreactors to monitor the cell concentration and viability during the cultivation process. Here, we demonstrate the microfluidic system performance by monitoring in real time the cell concentration and viability of yeast extracted directly from an in-house made bioreactor. This is the first demonstration of using the Dean drag force, generated due to the implementation of a curved microchannel geometry in conjunction with high flow rates, to promote passive mixing of cell samples and thus homogenization of the diluted cell plug. The autonomous operation of the fluidics furthermore allows implementation of intelligent protocols for administering air bubbles from the bioreactor in the microfluidic system, so that these will be guided away from the imaging region, thereby significantly improving both the robustness of the system and the quality of the data.
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Affiliation(s)
- P S Nunes
- Technical University of Denmark, Department for Micro- and Nanotechnology, Denmark.
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34
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Vannahme C, Sørensen KT, Gade C, Dufva M, Kristensen A. Refractometric monitoring of dissolution and fluid flow with distributed feedback dye laser sensor. Opt Express 2015; 23:6562-6568. [PMID: 25836874 DOI: 10.1364/oe.23.006562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Monitoring the dissolution of solid material in liquids and monitoring of fluid flow is of significant interest for applications in chemistry, food production, medicine, and especially in the fields of microfluidics and lab on a chip. Here, real-time refractometric monitoring of dissolution and fast fluid flow with DFB dye laser sensors with an optical imaging spectroscopy setup is presented. The dye laser sensors provide both low detection limits and high spatial resolution. It is demonstrated how the materials NaCl, sucrose, and bovine serum albumin show characteristic dissolution patterns. The unique feature of the presented method is a high frame rate of up to 20 Hz, which is proven to enable the monitoring of fast flow of a sucrose solution jet into pure water.
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35
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Søe MJ, Dufva M, Holmstrøm K. Detection of small noncoding RNAs by in situ hybridization using probes of 2'-O-methyl RNA + LNA. Methods Mol Biol 2015; 1173:113-21. [PMID: 24920364 DOI: 10.1007/978-1-4939-0931-5_10] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
In situ hybridization is a powerful method to provide information about contextual distribution and cellular origin of nucleic acids, e.g., in formalin-fixed paraffin-embedded (FFPE) samples of tissue. Particularly the recently discovered classes of noncoding RNA (ncRNA) including endo-siRNAs and microRNAs require such a technique to enable their study and visualization in natural contexts, and in the last decade, many advances have been made, increasing our ability to specifically detect small ncRNAs. One of the key developments has been the demonstration of the superiority of using locked nucleic acid (LNA)-modified DNA probes for the detection of ncRNA in tissue. Here, we describe an alternative in situ hybridization protocol employing oligonucleotide probes consisting of combinations of LNA and 2´-O-methyl RNAs that under optimized hybridization buffer conditions can provide a highly sensitive assay performance with only 1 h hybridization time.
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36
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Vedova PD, Ilieva M, Zhurbenko V, Mateiu R, Faralli A, Dufva M, Hansen O. Gold nanoparticle-based sensors activated by external radio frequency fields. Small 2015; 11:248-256. [PMID: 25180655 DOI: 10.1002/smll.201401187] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Revised: 07/04/2014] [Indexed: 06/03/2023]
Abstract
A novel molecular beacon (a nanomachine) is constructed that can be actuated by a radio frequency (RF) field. The nanomachine consists of the following elements arranged in molecular beacon configuration: a gold nanoparticle that acts both as quencher for fluorescence and a localized heat source; one reporter fluorochrome, and; a piece of DNA as a hinge and recognition sequence. When the nanomachines are irradiated with a 3 GHz RF field the fluorescence signal increases due to melting of the stem of the molecular beacon. A control experiment, performed using molecular beacons synthesized by substituting the gold nanoparticle by an organic quencher, shows no increase in fluorescence signal when exposed to the RF field. It may therefore be concluded that the increased fluorescence for the gold nanoparticle-conjugated nanomachines is not due to bulk heating of the solution, but is caused by the presence of the gold nanoparticles and their interaction with the RF field; however, existing models for heating of gold nanoparticles in a RF field are unable to explain the experimental results. Due to the biocompatibility of the construct and RF treatment, the nanomachines may possibly be used inside living cells. In a separate experiment a substantial increase in the dielectric losses can be detected in a RF waveguide setup coupled to a microfluidic channel when gold nanoparticles are added to a low RF loss liquid. This work sheds some light on RF heating of gold nanoparticles, which is a subject of significant controversy in the literature.
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Affiliation(s)
- Paolo Della Vedova
- DTU Nanotech Department of Micro- and Nanotechnology, Technical University of Denmark, Building 345E, DK-2800, Kgs. Lyngby, Denmark
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37
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Conde AJ, Bianchetti A, Veiras FE, Federico A, Cabaleiro JM, Dufva M, Madrid RE, Fraigi L. A polymer chip-integrable piezoelectric micropump with low backpressure dependence. RSC Adv 2015. [DOI: 10.1039/c5ra08819d] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A polymer piezoelectric micropump fabricated with conventional machining methods that can be embedded in laminated microfluidic chips.
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Affiliation(s)
- A. J. Conde
- Centro de Micro y Nanoelectrónica del Bicentenario (CMNB)
- Instituto Nacional de Tecnología Industrial (INTI)
- San Martín
- Argentina
| | | | - F. E. Veiras
- Electrónica e Informática
- INTI
- San Martín
- Argentina
- Laboratorio de Sistemas Líquidos
| | - A. Federico
- Electrónica e Informática
- INTI
- San Martín
- Argentina
| | - J. M. Cabaleiro
- Laboratorio de Fluidodinámica
- FIUBA
- Argentina
- Laboratorio de Micro y Nanofluídica y Plasma
- UdeMM
| | - M. Dufva
- DTU Nanotech
- Technical University of Denmark
- Denmark
| | - R. E. Madrid
- Instituto Superior de Investigaciones Biológicas (INSIBIO-CONICET)
- Laboratorio de Medios e Interfases (LAMEIN)
- Dpto. de Bioingeniería FACET/UNT
- Argentina
| | - L. Fraigi
- Centro de Micro y Nanoelectrónica del Bicentenario (CMNB)
- Instituto Nacional de Tecnología Industrial (INTI)
- San Martín
- Argentina
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38
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Uthuppu B, Heiskanen A, Kofoed D, Aamand J, Jørgensen C, Dufva M, Jakobsen MH. Micro-flow-injection analysis (μFIA) immunoassay of herbicide residue 2,6-dichlorobenzamide – towards automated at-line monitoring using modular microfluidics. Analyst 2015; 140:1616-23. [DOI: 10.1039/c4an01576b] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
A prototype microfluidic immunosensor for detecting 2,6-dichlorobenzamide showing potential for at-line monitoring of ground water.
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Affiliation(s)
- Basil Uthuppu
- Department of Micro- and Nanotechnology
- Technical University of Denmark
- 2800 Kgs. Lyngby
- Denmark
| | - Arto Heiskanen
- Department of Micro- and Nanotechnology
- Technical University of Denmark
- 2800 Kgs. Lyngby
- Denmark
| | - Dan Kofoed
- Department of Micro- and Nanotechnology
- Technical University of Denmark
- 2800 Kgs. Lyngby
- Denmark
| | - Jens Aamand
- The Geological Survey of Denmark and Greenland (GEUS)
- 1350 Copenhagen
- Denmark
| | | | - Martin Dufva
- Department of Micro- and Nanotechnology
- Technical University of Denmark
- 2800 Kgs. Lyngby
- Denmark
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39
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Canali C, Mohanty S, Heiskanen A, Muhammad HB, Martinsen ØG, Dufva M, Wolff A, Emnéus J. Impedance Spectroscopic Characterisation of Porosity in 3D Cell Culture Scaffolds with Different Channel Networks. ELECTROANAL 2014. [DOI: 10.1002/elan.201400413] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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40
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Christiansen A, Hansen CS, Kringelum JV, Lund O, Bogh KL, Dufva M. A novel approach for characterisation of conformational allergen epitopes combining phage display and high-throughput sequencing. Clin Transl Allergy 2014. [PMCID: PMC4072304 DOI: 10.1186/2045-7022-4-s2-p27] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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41
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Rizzi G, Westergaard Østerberg F, Dufva M, Fougt Hansen M. Magnetoresistive sensor for real-time single nucleotide polymorphism genotyping. Biosens Bioelectron 2014; 52:445-51. [DOI: 10.1016/j.bios.2013.09.026] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Revised: 08/15/2013] [Accepted: 09/03/2013] [Indexed: 12/17/2022]
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42
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Zór K, Heiskanen A, Caviglia C, Vergani M, Landini E, Shah F, Carminati M, Martínez-Serrano A, Moreno TR, Kokaia M, Benayahu D, Keresztes Z, Papkovsky D, Wollenberger U, Svendsen WE, Dimaki M, Ferrari G, Raiteri R, Sampietro M, Dufva M, Emnéus J. A compact multifunctional microfluidic platform for exploring cellular dynamics in real-time using electrochemical detection. RSC Adv 2014. [DOI: 10.1039/c4ra12632g] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Dopamine detection from PC12 cell populations and monitoring of yeast redox metabolism demonstrate the multifunctionality of the compact microfluidic cell culture and electrochemical analysis platform with in-built fluid handling and detection unit.
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Affiliation(s)
- K. Zór
- Department of Micro- and Nanotechnology
- Technical University of Denmark
- DK-2800 Kgs. Lyngby, Denmark
| | - A. Heiskanen
- Department of Micro- and Nanotechnology
- Technical University of Denmark
- DK-2800 Kgs. Lyngby, Denmark
| | - C. Caviglia
- Department of Micro- and Nanotechnology
- Technical University of Denmark
- DK-2800 Kgs. Lyngby, Denmark
| | - M. Vergani
- Dipartimento di Elettronica
- Informazione e Bioingegneria
- Politecnico di Milano
- Milan, Italy
| | - E. Landini
- Department of Informatics, Bioengineering, Robotics, and System Engineering
- University of Genova
- Genova, Italy
| | - F. Shah
- Department of Micro- and Nanotechnology
- Technical University of Denmark
- DK-2800 Kgs. Lyngby, Denmark
| | - M. Carminati
- Dipartimento di Elettronica
- Informazione e Bioingegneria
- Politecnico di Milano
- Milan, Italy
| | - A. Martínez-Serrano
- Department of Molecular Biology and Center of Molecular Biology “Severo Ochoa”
- University Autónoma de Madrid
- Madrid, Spain
| | - T. Ramos Moreno
- Department of Molecular Biology and Center of Molecular Biology “Severo Ochoa”
- University Autónoma de Madrid
- Madrid, Spain
- Wallenberg Neuroscience Center
- Lund University
| | - M. Kokaia
- Wallenberg Neuroscience Center
- Lund University
- Lund, Sweden
| | - D. Benayahu
- Department of Cell and Developmental Biology
- Tel Aviv University
- Ramat Aviv, Israel
| | - Zs. Keresztes
- Research Center for Natural Sciences
- Hungarian Academy of Sciences
- Budapest, Hungary
| | - D. Papkovsky
- Department of Biochemistry and Cell Biology
- University College Cork
- Cork, Ireland
| | - U. Wollenberger
- Department of Molecular Enzymology
- University of Potsdam
- Potsdam (Golm), Germany
| | - W. E. Svendsen
- Department of Micro- and Nanotechnology
- Technical University of Denmark
- DK-2800 Kgs. Lyngby, Denmark
| | - M. Dimaki
- Department of Micro- and Nanotechnology
- Technical University of Denmark
- DK-2800 Kgs. Lyngby, Denmark
| | - G. Ferrari
- Dipartimento di Elettronica
- Informazione e Bioingegneria
- Politecnico di Milano
- Milan, Italy
| | - R. Raiteri
- Department of Informatics, Bioengineering, Robotics, and System Engineering
- University of Genova
- Genova, Italy
| | - M. Sampietro
- Dipartimento di Elettronica
- Informazione e Bioingegneria
- Politecnico di Milano
- Milan, Italy
| | - M. Dufva
- Department of Micro- and Nanotechnology
- Technical University of Denmark
- DK-2800 Kgs. Lyngby, Denmark
| | - J. Emnéus
- Department of Micro- and Nanotechnology
- Technical University of Denmark
- DK-2800 Kgs. Lyngby, Denmark
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Ilieva M, Della Vedova P, Hansen O, Dufva M. Tracking neuronal marker expression inside living differentiating cells using molecular beacons. Front Cell Neurosci 2013; 7:266. [PMID: 24431988 PMCID: PMC3883158 DOI: 10.3389/fncel.2013.00266] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2013] [Accepted: 12/03/2013] [Indexed: 01/14/2023] Open
Abstract
Monitoring gene expression is an important tool for elucidating mechanisms of cellular function. In order to monitor gene expression during nerve cell development, molecular beacon (MB) probes targeting markers representing different stages of neuronal differentiation were designed and synthesized as 2'-O-methyl RNA backbone oligonucleotides. MBs were transfected into human mesencephalic cells (LUHMES) using streptolysin-O-based membrane permeabilization. Mathematical modeling, simulations and experiments indicated that MB concentration was equal to the MB in the transfection medium after 10 min transfection. The cells will then each contain about 60,000 MBs. Gene expression was detected at different time points using fluorescence microscopy. Nestin and NeuN mRNA were expressed in approximately 35% of the LUHMES cells grown in growth medium, and in 80–90% of cells after differentiation. MAP2 and tyrosine hydroxylase mRNAs were expressed 2 and 3 days post induction of differentiation, respectively. Oct 4 was not detected with MB in these cells and signal was not increased over time suggesting that MB are generally stable inside the cells. The gene expression changes measured using MBs were confirmed using qRT-PCR. These results suggest that MBs are simple to use sensors inside living cell, and particularly useful for studying dynamic gene expression in heterogeneous cell populations.
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Affiliation(s)
- Mirolyuba Ilieva
- Department of Micro- and Nanotechnology, Technical University of Denmark Kgs. Lyngby, Denmark
| | - Paolo Della Vedova
- Department of Micro- and Nanotechnology, Technical University of Denmark Kgs. Lyngby, Denmark
| | - Ole Hansen
- Department of Micro- and Nanotechnology, Technical University of Denmark Kgs. Lyngby, Denmark ; Center for Individual Nanoparticle Functionality, Technical University of Denmark Kgs. Lyngby, Denmark
| | - Martin Dufva
- Department of Micro- and Nanotechnology, Technical University of Denmark Kgs. Lyngby, Denmark
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Ilieva M, Dufva M. SOX2 and OCT4 mRNA-expressing cells, detected by molecular beacons, localize to the center of neurospheres during differentiation. PLoS One 2013; 8:e73669. [PMID: 24013403 PMCID: PMC3754928 DOI: 10.1371/journal.pone.0073669] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Accepted: 07/19/2013] [Indexed: 12/26/2022] Open
Abstract
Neurospheres are used as in vitro assay to measure the properties of neural stem cells. To investigate the molecular and phenotypic heterogeneity of neurospheres, molecular beacons (MBs) targeted against the stem cell markers OCT4 and SOX2 were designed, and synthesized with a 2'-O-methyl RNA backbone. OCT4 and SOX2 MBs were transfected into human embryonic mesencephalon derived cells, which spontaneously form neurospheres when grown on poly-L-ornitine/fibronectin matrix and medium complemented with bFGF. OCT4 and SOX2 gene expression were tracked in individual cell using the MBs. Quantitative image analysis every day for seven days showed that the OCT4 and SOX2 mRNA-expressing cells clustered in the centre of the neurospheres cultured in differentiation medium. By contrast, cells at the periphery of the differentiating spheres developed neurite outgrowths and expressed the tyrosine hydroxylase protein, indicating terminal differentiation. Neurospheres cultured in growth medium contained OCT4 and SOX2-positive cells distributed throughout the entire sphere, and no differentiating neurones. Gene expression of SOX2 and OCT4 mRNA detected by MBs correlated well with gene and protein expression measured by qRT-PCR and immunostaining, respectively. These experimental data support the theoretical model that stem cells cluster in the centre of neurospheres, and demonstrate the use of MBs for the spatial localization of specific gene-expressing cells within heterogeneous cell populations.
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Affiliation(s)
- Mirolyuba Ilieva
- Department of Micro- and Nanotechnology, Technical University of Denmark, Lyngby, Denmark
| | - Martin Dufva
- Department of Micro- and Nanotechnology, Technical University of Denmark, Lyngby, Denmark
- * E-mail:
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45
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Heiskanen A, Coman V, Kostesha N, Sabourin D, Haslett N, Baronian K, Gorton L, Dufva M, Emnéus J. Bioelectrochemical probing of intracellular redox processes in living yeast cells—application of redox polymer wiring in a microfluidic environment. Anal Bioanal Chem 2013; 405:3847-58. [DOI: 10.1007/s00216-013-6709-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2012] [Revised: 12/10/2012] [Accepted: 01/09/2013] [Indexed: 01/13/2023]
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Vergani M, Carminati M, Ferrari G, Landini E, Caviglia C, Heiskanen A, Comminges C, Zór K, Sabourin D, Dufva M, Dimaki M, Raiteri R, Wollenberger U, Emneus J, Sampietro M. Multichannel bipotentiostat integrated with a microfluidic platform for electrochemical real-time monitoring of cell cultures. IEEE Trans Biomed Circuits Syst 2012; 6:498-507. [PMID: 23853236 DOI: 10.1109/tbcas.2012.2187783] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
An electrochemical detection system specifically designed for multi-parameter real-time monitoring of stem cell culturing/differentiation in a microfluidic system is presented. It is composed of a very compact 24-channel electronic board, compatible with arrays of microelectrodes and coupled to a microfluidic cell culture system. A versatile data acquisition software enables performing amperometry, cyclic voltammetry and impedance spectroscopy in each of the 12 independent chambers over a 100 kHz bandwidth with current resolution down to 5 pA for 100 ms measuring time. The design of the platform, its realization and experimental characterization are reported, with emphasis on the analysis of impact of input capacitance (i.e., microelectrode size) and microfluidic pump operation on current noise. Programmable sequences of successive injections of analytes (ferricyanide and dopamine) and rinsing buffer solution as well as the impedimetric continuous tracking for seven days of the proliferation of a colony of PC12 cells are successfully demonstrated.
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Affiliation(s)
- Marco Vergani
- Dipartimento di Elettronica e Informazione, Politecnico diMilano, 20133Milano, Italy.
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Sabourin D, Skafte-Pedersen P, Søe MJ, Hemmingsen M, Alberti M, Coman V, Petersen J, Emnéus J, Kutter JP, Snakenborg D, Jørgensen F, Clausen C, Holmstrøm K, Dufva M. The MainSTREAM component platform: a holistic approach to microfluidic system design. ACTA ACUST UNITED AC 2012; 18:212-28. [PMID: 23015520 DOI: 10.1177/2211068212461445] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A microfluidic component library for building systems driving parallel or serial microfluidic-based assays is presented. The components are a miniaturized eight-channel peristaltic pump, an eight-channel valve, sample-to-waste liquid management, and interconnections. The library of components was tested by constructing various systems supporting perfusion cell culture, automated DNA hybridizations, and in situ hybridizations. The results showed that the MainSTREAM components provided (1) a rapid, robust, and simple method to establish numerous fluidic inputs and outputs to various types of reaction chips; (2) highly parallel pumping and routing/valving capability; (3) methods to interface pumps and chip-to-liquid management systems; (4) means to construct a portable system; (5) reconfigurability/flexibility in system design; (6) means to interface to microscopes; and (7) compatibility with tested biological methods. It was found that LEGO Mindstorms motors, controllers, and software were robust, inexpensive, and an accessible choice as compared with corresponding custom-made actuators. MainSTREAM systems could operate continuously for weeks without leaks, contamination, or system failures. In conclusion, the MainSTREAM components described here meet many of the demands on components for constructing and using microfluidics systems.
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Affiliation(s)
- David Sabourin
- DTU Nanotech, Dept. of Micro- and Nanotechnology, Technical University of Denmark, Kgs. Lyngby, Denmark
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Skolimowski M, Weiss Nielsen M, Abeille F, Skafte-Pedersen P, Sabourin D, Fercher A, Papkovsky D, Molin S, Taboryski R, Sternberg C, Dufva M, Geschke O, Emnéus J. Modular microfluidic system as a model of cystic fibrosis airways. Biomicrofluidics 2012; 6:34109. [PMID: 23908680 PMCID: PMC3423306 DOI: 10.1063/1.4742911] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2012] [Accepted: 07/24/2012] [Indexed: 05/13/2023]
Abstract
A modular microfluidic airways model system that can simulate the changes in oxygen tension in different compartments of the cystic fibrosis (CF) airways was designed, developed, and tested. The fully reconfigurable system composed of modules with different functionalities: multichannel peristaltic pumps, bubble traps, gas exchange chip, and cell culture chambers. We have successfully applied this system for studying the antibiotic therapy of Pseudomonas aeruginosa, the bacteria mainly responsible for morbidity and mortality in cystic fibrosis, in different oxygen environments. Furthermore, we have mimicked the bacterial reinoculation of the aerobic compartments (lower respiratory tract) from the anaerobic compartments (cystic fibrosis sinuses) following an antibiotic treatment. This effect is hypothesised as the one on the main reasons for recurrent lung infections in cystic fibrosis patients.
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Affiliation(s)
- M Skolimowski
- Department of Micro- and Nanotechnology, Technical University of Denmark, Ørsted Plads, Building 345B, Kgs. Lyngby DK-2800, Denmark ; Department of Systems Biology, Technical University of Denmark, Matematiktorvet, Building 301, Kgs. Lyngby DK-2800, Denmark
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Łopacińska JM, Grădinaru C, Wierzbicki R, Købler C, Schmidt MS, Madsen MT, Skolimowski M, Dufva M, Flyvbjerg H, Mølhave K. Cell motility, morphology, viability and proliferation in response to nanotopography on silicon black. Nanoscale 2012; 4:3739-3745. [PMID: 22614757 DOI: 10.1039/c2nr11455k] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Knowledge of cells' interactions with nanostructured materials is fundamental for bio-nanotechnology. We present results for how individual mouse fibroblasts from cell line NIH3T3 respond to highly spiked surfaces of silicon black that were fabricated by maskless reactive ion etching (RIE). We did standard measurements of cell viability, proliferation, and morphology on various surfaces. We also analyzed the motility of cells on the same surfaces, as recorded in time lapse movies of sparsely populated cell cultures. We find that motility and morphology vary strongly with nano-patterns, while viability and proliferation show little dependence on substrate type. We conclude that motility analysis can show a wide range of cell responses e.g. over a factor of two in cell speed to different nano-topographies, where standard assays, such as viability or proliferation, in the tested cases show much less variation of the order 10-20%.
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Affiliation(s)
- Joanna M Łopacińska
- Department of Micro- and Nanotechnology, Technical University of Denmark, Ørsteds Plads 345a, 2800 Kongens Lyngby, Denmark.
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Søe MJ, Okkels F, Sabourin D, Alberti M, Holmstrøm K, Dufva M. HistoFlex--a microfluidic device providing uniform flow conditions enabling highly sensitive, reproducible and quantitative in situ hybridizations. Lab Chip 2011; 11:3896-3907. [PMID: 21964811 DOI: 10.1039/c1lc20748b] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
A microfluidic device (the HistoFlex) designed to perform and monitor molecular biological assays under dynamic flow conditions on microscope slide-substrates, with special emphasis on analyzing histological tissue sections, is presented. Microscope slides were reversibly sealed onto a cast polydimethylsiloxane (PDMS) insert, patterned with distribution channels and reaction chambers. Topology optimization was used to design reaction chambers with uniform flow conditions. The HistoFlex provided uniform hybridization conditions, across the reaction chamber, as determined by hybridization to microscope slides of spotted DNA microarrays when applying probe concentrations generally used in in situ hybridization (ISH) assays. The HistoFlex's novel ability in online monitoring of an in situ hybridization assay was demonstrated using direct fluorescent detection of hybridization to 18S rRNA. Tissue sections were not visually damaged during assaying, which enabled adapting a complete ISH assay for detection of microRNAs (miRNA). The effects of flow based incubations on hybridization, antibody incubation and Tyramide Signal Amplification (TSA) steps were investigated upon adapting the ISH assay for performing in the HistoFlex. The hybridization step was significantly enhanced using flow based incubations due to improved hybridization efficiency. The HistoFlex device enabled a fast miRNA ISH assay (3 hours) which provided higher hybridization signal intensity compared to using conventional techniques (5 h 40 min). We further demonstrate that the improved hybridization efficiency using the HistoFlex permits more complex assays e.g. those comprising sequential hybridization and detection of two miRNAs to be performed with significantly increased sensitivity. The HistoFlex provides a new histological analysis platform that will allow multiple and sequential assays to be performed under their individual optimum assay conditions. Images can subsequently be recorded either in combination or sequentially through the ability of the HistoFlex to monitor assays without disassembly.
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