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Boulais E, Gervais T. The 2D microfluidics cookbook - modeling convection and diffusion in plane flow devices. Lab Chip 2023; 23:1967-1980. [PMID: 36884010 DOI: 10.1039/d2lc01033j] [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] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
A growing number of microfluidic systems operate not through networks of microchannels but instead through using 2D flow fields. While the design rules for channel networks are already well-known and exposed in microfluidics textbooks, the knowledge underlying transport in 2D microfluidics remains scattered piecemeal and is not easily accessible to experimentalists and engineers. In this tutorial review, we formulate a unified framework for understanding, analyzing and designing 2D microfluidic technologies. We first show how a large number of seemingly different devices can all be modelled using the same concepts, namely flow and diffusion in a Hele-Shaw cell. We then expose a handful of mathematical tools, accessible to any engineer with undergraduate level mathematics knowledge, namely potential flow, superposition of charges, conformal transforms and basic convection-diffusion. We show how these tools can be combined to obtain a simple "recipe" that models almost any imaginable 2D microfluidic system. We end by pointing to more advanced topics beyond 2D microfluidics, namely interface problems and flow and diffusion in the third dimension. This forms the basis of a complete theory allowing for the design and operation of new microfluidic systems.
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Affiliation(s)
- Etienne Boulais
- Polytechnique Montreal, 2500 Chemin de Polytechnique, Montréal, QC H3T 1J4, Canada.
| | - Thomas Gervais
- Polytechnique Montreal, 2500 Chemin de Polytechnique, Montréal, QC H3T 1J4, Canada.
- Institut du Cancer de Montréal (ICM) and Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Canada
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2
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Taylor DP, Mathur P, Renaud P, Kaigala GV. Microscale hydrodynamic confinements: shaping liquids across length scales as a toolbox in life sciences. Lab Chip 2022; 22:1415-1437. [PMID: 35348555 DOI: 10.1039/d1lc01101d] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Hydrodynamic phenomena can be leveraged to confine a range of biological and chemical species without needing physical walls. In this review, we list methods for the generation and manipulation of microfluidic hydrodynamic confinements in free-flowing liquids and near surfaces, and elucidate the associated underlying theory and discuss their utility in the emerging area of open space microfluidics applied to life-sciences. Microscale hydrodynamic confinements are already starting to transform approaches in fundamental and applied life-sciences research from precise separation and sorting of individual cells, allowing localized bio-printing to multiplexing for clinical diagnosis. Through the choice of specific flow regimes and geometrical boundary conditions, hydrodynamic confinements can confine species across different length scales from small molecules to large cells, and thus be applied to a wide range of functionalities. We here provide practical examples and implementations for the formation of these confinements in different boundary conditions - within closed channels, in between parallel plates and in an open liquid volume. Further, to enable non-microfluidics researchers to apply hydrodynamic flow confinements in their work, we provide simplified instructions pertaining to their design and modelling, as well as to the formation of hydrodynamic flow confinements in the form of step-by-step tutorials and analytical toolbox software. This review is written with the idea to lower the barrier towards the use of hydrodynamic flow confinements in life sciences research.
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Affiliation(s)
- David P Taylor
- IBM Research - Europe, Säumerstrasse 4, 8803 Rüschlikon, Switzerland.
- Microsystems Laboratory 4, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Prerit Mathur
- IBM Research - Europe, Säumerstrasse 4, 8803 Rüschlikon, Switzerland.
- Dept. of Chemistry and Applied Biosciences, Eidgenössische Technische Hochschule (ETH), Vladimir-Prelog-Weg 1-5/10, 8093 Zurich, Switzerland
| | - Philippe Renaud
- Microsystems Laboratory 4, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Govind V Kaigala
- IBM Research - Europe, Säumerstrasse 4, 8803 Rüschlikon, Switzerland.
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Abstract
Patterning biomolecules on surfaces provides numerous opportunities for miniaturizing biological assays; biosensing; studying proteins, cells, and tissue sections; and engineering surfaces that include biological components. In this Feature Article, we summarize the themes presented in our recent Langmuir Lecture on patterning biomolecules on surfaces, miniaturizing surface assays, and interacting with biointerfaces using three key technologies: microcontact printing, microfluidic networks, and microfluidic probes.
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Affiliation(s)
- Emmanuel Delamarche
- IBM Research Europe-Zurich, Säumerstrasse 4, Rüschlikon CH-8803, Switzerland
| | - Iago Pereiro
- IBM Research Europe-Zurich, Säumerstrasse 4, Rüschlikon CH-8803, Switzerland
| | - Aditya Kashyap
- IBM Research Europe-Zurich, Säumerstrasse 4, Rüschlikon CH-8803, Switzerland
| | - Govind V Kaigala
- IBM Research Europe-Zurich, Säumerstrasse 4, Rüschlikon CH-8803, Switzerland
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Pereiro I, Fomitcheva Khartchenko A, Lovchik RD, Kaigala GV. Advection-Enhanced Kinetics in Microtiter Plates for Improved Surface Assay Quantitation and Multiplexing Capabilities. Angew Chem Int Ed Engl 2021; 60:20935-20942. [PMID: 34296491 DOI: 10.1002/anie.202107424] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [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: 06/03/2021] [Indexed: 12/28/2022]
Abstract
Surface assays such as ELISA are pervasive in clinics and research and predominantly standardized in microtiter plates (MTP). MTPs provide many advantages but are often detrimental to surface assay efficiency due to inherent mass transport limitations. Microscale flows can overcome these and largely improve assay kinetics. However, the disruptive nature of microfluidics with existing labware and protocols has narrowed its transformative potential. We present WellProbe, a novel microfluidic concept compatible with MTPs. With it, we show that immunoassays become more sensitive at low concentrations (up to 9× signal improvement in 12× less time), richer in information with 3-4 different kinetic conditions, and can be used to estimate kinetic parameters, minimize washing steps and non-specific binding, and identify compromised results. We further multiplex single-well assays combining WellProbe's kinetic regions with tailored microarrays. Finally, we demonstrate our system in a context of immunoglobulin subclass evaluation, increasingly regarded as clinically relevant.
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Affiliation(s)
- Iago Pereiro
- IBM Research-Europe, Säumerstrasse 4, 8803, Rüschlikon, Switzerland
| | | | - Robert D Lovchik
- IBM Research-Europe, Säumerstrasse 4, 8803, Rüschlikon, Switzerland
| | - Govind V Kaigala
- IBM Research-Europe, Säumerstrasse 4, 8803, Rüschlikon, Switzerland
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5
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Pereiro I, Fomitcheva Khartchenko A, Lovchik RD, Kaigala GV. Advection‐Enhanced Kinetics in Microtiter Plates for Improved Surface Assay Quantitation and Multiplexing Capabilities. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202107424] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Iago Pereiro
- IBM Research—Europe Säumerstrasse 4 8803 Rüschlikon Switzerland
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Abstract
An increasing number of applications in biology, chemistry, and material sciences require fluid manipulation beyond what is possible with current automated pipette handlers, such as gradient generation, interface reactions, reagent streaming, and reconfigurability. In this article, we introduce the pixelated chemical display (PCD), a scalable strategy for highly parallel, reconfigurable liquid handling on open surfaces. Microfluidic "pixels" are created when a fluid stream injected above a surface is confined by neighboring identical fluid streams, forming a repeatable flow unit that can be used to tesselate a surface. PCDs generating up to 144 pixels are fabricated and used to project "chemical moving pictures" made of several reagents over both immersed and dry surfaces, without any physical barrier or wall. This work distinguishes itself from previous work in open-space microfluidics by presenting a device architecture where the number of confinement areas can be scaled to any size. Furthermore, it challenges the open-space tenet that the aspiration rate must be higher than the injection rate for reagents to be confined. Overall, this article sets the foundation for massively parallel surface processing using continuous flow streams and showcases possibilities in both wet and dry surface patterning and roll-to-roll processes.
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Affiliation(s)
| | - Étienne Boulais
- Department of Engineering Physics, École Polytechnique de Montréal, Montréal, QC H3T 1J4, Canada
| | - Maude Tremblay
- Department of Engineering Physics, École Polytechnique de Montréal, Montréal, QC H3T 1J4, Canada
| | - Thomas Gervais
- Institut de Génie Biomédical, Polytechnique Montréal, Montréal, QC H3T 1J4, Canada;
- Department of Engineering Physics, École Polytechnique de Montréal, Montréal, QC H3T 1J4, Canada
- Institut du Cancer de Montréal, Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montréal, QC H2X 0C1, Canada
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Romanov V, Brooks BD. Antibody Printing Technologies. Methods Mol Biol 2021; 2237:151-77. [PMID: 33237416 DOI: 10.1007/978-1-0716-1064-0_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2023]
Abstract
Antibody microarrays are routinely employed in the lab and in the clinic for studying protein expression, protein-protein, and protein-drug interactions. The microarray format reduces the size scale at which biological and biochemical interactions occur, leading to large reductions in reagent consumption and handling times while increasing overall experimental throughput. Specifically, antibody microarrays, as a platform, offer a number of different advantages over traditional techniques in the areas of drug discovery and diagnostics. While a number of different techniques and approaches have been developed for creating micro and nanoscale antibody arrays, issues relating to sensitivity, cost, and reproducibility persist. The aim of this review is to highlight current state-of the-art techniques and approaches for creating antibody arrays by providing latest accounts of the field while discussing potential future directions.
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Verlinden EJ, Madadelahi M, Sarajlic E, Shamloo A, Engel AH, Staufer U, Ghatkesar MK. Volume and concentration dosing in picolitres using a two-channel microfluidic AFM cantilever. Nanoscale 2020; 12:10292-10305. [PMID: 32363366 DOI: 10.1039/c9nr10494a] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
We introduce a two-channel microfluidic atomic force microscopy (AFM) cantilever that combines the nanomechanical sensing functionality of an AFM cantilever with the ability to manipulate fluids of picolitres or smaller volumes through nanoscale apertures near the cantilever tip. Each channel is connected to a separate fluid reservoir, which can be independently controlled by pressure. Various systematic experiments with fluorescent liquids were done by either injecting the liquids from the on-chip reservoir or aspirating directly through the nanoscale apertures at the tip. A flow rate analysis of volume dosing, aspiration and concentration dosing inside the liquid medium was performed. To understand the fluid behaviour, an analytical model based on the hydrodynamic resistance, as well as numerical flow simulations of single and multi-phase conditions were performed and compared. By applying pressures between -500 mbar and 500 mbar to the reservoirs of the probe with respect to the ambient pressure, flow rates ranging from 10 fl s-1 to 83 pl s-1 were obtained inside the channels of the cantilever as predicted by the analytical model. The smallest dosing flow rate through the apertures was 720 fl s-1, which was obtained with a 10 mbar pressure on one reservoir and ambient pressure on the other. The solute concentration in the outflow could be tuned to values between 0% and 100% by pure convection and to values between 17.5% and 90% in combination with diffusion. The results prove that this new probe enables handling multiple fluids with the scope to inject different concentrations of analytes inside a single living cell and also perform regular AFM functionalities.
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Affiliation(s)
- E J Verlinden
- Department of Precision and Microsystems Engineering, Delft University of Technology, The Netherlands.
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Abstract
The theoretical analysis and experimental demonstration of a new concept are presented for a non-contact scanning probe, in which transport of fluid and molecules is controlled by electric fields. The electrokinetic scanning probe (ESP) enables local chemical and biochemical interactions with surfaces in liquid environments. The physical mechanism and design criteria for such a probe are presented, and its compatibility with a wide range of processing solutions and pH values are demonstrated. The applicability of the probe is shown for surface patterning in conjunction with localized heating and 250-fold analyte stacking.
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Affiliation(s)
- Nadya Ostromohov
- Faculty of Mechanical Engineering, Technion-Israel Institute of Technology, Haifa, 3200003, Israel
- IBM Research-Zurich, Saeumerstrasse 4, CH-8803, Rueschlikon, Switzerland
| | - Baruch Rofman
- Faculty of Mechanical Engineering, Technion-Israel Institute of Technology, Haifa, 3200003, Israel
| | - Moran Bercovici
- Faculty of Mechanical Engineering, Technion-Israel Institute of Technology, Haifa, 3200003, Israel
| | - Govind Kaigala
- IBM Research-Zurich, Saeumerstrasse 4, CH-8803, Rueschlikon, Switzerland
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Lovchik RD, Taylor D, Kaigala G. Rapid micro-immunohistochemistry. Microsyst Nanoeng 2020; 6:94. [PMID: 34567704 PMCID: PMC8433409 DOI: 10.1038/s41378-020-00205-2] [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] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 08/06/2020] [Accepted: 08/07/2020] [Indexed: 05/04/2023]
Abstract
We present a new and versatile implementation of rapid and localized immunohistochemical staining of tissue sections. Immunohistochemistry (IHC) comprises a sequence of specific biochemical reactions and allows the detection of specific proteins in tissue sections. For the rapid implementation of IHC, we fabricated horizontally oriented microfluidic probes (MFPs) with functionally designed apertures to enable square and circular footprints, which we employ to locally expose a tissue to time-optimized sequences of different biochemicals. We show that the two main incubation steps of IHC protocols can be performed on MDAMB468-1510A cell block sections in less than 30 min, compared to incubation times of an hour or more in standard protocols. IHC analysis on the timescale of tens of minutes could potentially be applied during surgery, enabling clinicians to react in more dynamically and efficiently. Furthermore, this rapid IHC implementation along with conservative tissue usage has strong potential for the implementation of multiplexed assays, allowing the exploration of optimal assay conditions with a small amount of tissue to ensure high-quality staining results for the remainder of the sample.
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Affiliation(s)
- Robert D. Lovchik
- IBM Research Europe, Saeumerstrasse 4, 8803 Rueschlikon, Switzerland
| | - David Taylor
- IBM Research Europe, Saeumerstrasse 4, 8803 Rueschlikon, Switzerland
- Present Address: Eidgenössische Technische Hochschule Zürich, Department of Mechanical and Process Engineering, Sonneggstrasse 3, 8092 Zurich, Switzerland
| | - Govind Kaigala
- IBM Research Europe, Saeumerstrasse 4, 8803 Rueschlikon, Switzerland
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12
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Goyette PA, Boulais É, Normandeau F, Laberge G, Juncker D, Gervais T. Microfluidic multipoles theory and applications. Nat Commun 2019; 10:1781. [PMID: 30992450 PMCID: PMC6467910 DOI: 10.1038/s41467-019-09740-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [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] [Received: 10/02/2018] [Accepted: 03/14/2019] [Indexed: 11/09/2022] Open
Abstract
Microfluidic multipoles (MFMs) have been realized experimentally and hold promise for "open-space" biological and chemical surface processing. Whereas convective flow can readily be predicted using hydraulic-electrical analogies, the design of advanced microfluidic multipole is constrained by the lack of simple, accurate models to predict mass transport within them. In this work, we introduce the complete solutions to mass transport in multipolar microfluidics based on the iterative conformal mapping of 2D advection-diffusion around a simple edge into dipoles and multipolar geometries, revealing a rich landscape of transport modes. The models are validated experimentally with a library of 3D printed devices and found in excellent agreement. Following a theory-guided design approach, we further ideate and fabricate two classes of spatiotemporally reconfigurable multipolar devices that are used for processing surfaces with time-varying reagent streams, and to realize a multistep automated immunoassay. Overall, the results set the foundations for exploring, developing, and applying open-space microfluidic multipoles.
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Affiliation(s)
| | - Étienne Boulais
- Department of Engineering Physics, École Polytechnique de Montréal, Montréal, QC, H3T 1J4, Canada
| | - Frédéric Normandeau
- Biomedical Engineering Department and Genome Quebec Innovation Centre, McGill University, Montreal, QC, H3A 0G1, Canada
| | - Gabriel Laberge
- Department of Engineering Physics, École Polytechnique de Montréal, Montréal, QC, H3T 1J4, Canada
| | - David Juncker
- Biomedical Engineering Department and Genome Quebec Innovation Centre, McGill University, Montreal, QC, H3A 0G1, Canada
| | - Thomas Gervais
- Institut de Génie Biomédical, École Polytechnique de Montréal, Montréal, QC, H3T 1J4, Canada. .,Department of Engineering Physics, École Polytechnique de Montréal, Montréal, QC, H3T 1J4, Canada. .,Institut du Cancer de Montréal, Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montréal, QC, H2X 0C1, Canada.
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Arar NM, Pati P, Kashyap A, Khartchenko AF, Goksel O, Kaigala GV, Gabrani M. High-Quality Immunohistochemical Stains Through Computational Assay Parameter Optimization. IEEE Trans Biomed Eng 2019; 66:2952-2963. [PMID: 30762525 DOI: 10.1109/tbme.2019.2899156] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Accurate profiling of tumors using immunohistochemistry (IHC) is essential in cancer diagnosis. The inferences drawn from IHC-stained images depend to a great extent on the quality of immunostaining, which is in turn affected strongly by assay parameters. To optimize assay parameters, the available tissue sample is often limited. Moreover, with current practices in pathology, exploring the entire assay parameter space is not feasible. Thus, the evaluation of IHC stained slides is conventionally a subjective task, in which diagnoses are commonly drawn on images that are suboptimal. In this work, we introduce a framework to analyze IHC staining quality and its sensitivity to process parameters. To that extent, first histopathological sections are segmented automatically. Then, machine learning techniques are employed to extract disease-specific staining quality metrics (SQMs) targeting a quantitative assessment of staining quality. Finally, an approach to efficiently analyze the parameter space is introduced to infer sensitivity to process parameters. We present results on microscale IHC tissue samples of five breast tumor classes, based on disease state and protein expression. A disease-type classification F1-score of 0.82 and a contrast-level classification F1-score of 0.95 were achieved. With the proposed SQMs, an area under the curve of 0.85 was achieved on average over different disease types. Our methodology provides a promising step in automatically evaluating and quantifying staining quality of IHC stained tissue sections, and it can potentially standardize immunostaining across diagnostic laboratories.
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Huber D, Kaigala GV. Rapid micro fluorescence in situ hybridization in tissue sections. Biomicrofluidics 2018; 12:042212. [PMID: 29887936 PMCID: PMC5976495 DOI: 10.1063/1.5023775] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2018] [Accepted: 03/29/2018] [Indexed: 05/04/2023]
Abstract
This paper describes a micro fluorescence in situ hybridization (μFISH)-based rapid detection of cytogenetic biomarkers on formalin-fixed paraffin embedded (FFPE) tissue sections. We demonstrated this method in the context of detecting human epidermal growth factor 2 (HER2) in breast tissue sections. This method uses a non-contact microfluidic scanning probe (MFP), which localizes FISH probes at the micrometer length-scale to selected cells of the tissue section. The scanning ability of the MFP allows for a versatile implementation of FISH on tissue sections. We demonstrated the use of oligonucleotide FISH probes in ethylene carbonate-based buffer enabling rapid hybridization within <1 min for chromosome enumeration and 10-15 min for assessment of the HER2 status in FFPE sections. We further demonstrated recycling of FISH probes for multiple sequential tests using a defined volume of probes by forming hierarchical hydrodynamic flow confinements. This microscale method is compatible with the standard FISH protocols and with the Instant Quality FISH assay and reduces the FISH probe consumption ∼100-fold and the hybridization time 4-fold, resulting in an assay turnaround time of <3 h. We believe that rapid μFISH has the potential of being used in pathology workflows as a standalone method or in combination with other molecular methods for diagnostic and prognostic analysis of FFPE sections.
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Cors JF, Kashyap A, Fomitcheva Khartchenko A, Schraml P, Kaigala GV. Tissue lithography: Microscale dewaxing to enable retrospective studies on formalin-fixed paraffin-embedded (FFPE) tissue sections. PLoS One 2017; 12:e0176691. [PMID: 28493979 DOI: 10.1371/journal.pone.0176691] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Accepted: 04/16/2017] [Indexed: 01/01/2023] Open
Abstract
We present a new concept, termed tissue lithography (TL), and its implementation which enables retrospective studies on formalin-fixed paraffin-embedded tissue sections. Tissue lithography uses a microfluidic probe to remove microscale areas of the paraffin layer on formalin-fixed paraffin-embedded biopsy samples. Current practices in sample utilization for research and diagnostics require complete deparaffinization of the sample prior to molecular testing. This imposes strong limitations in terms of the number of tests as well as the time when they can be performed on a single sample. Microscale dewaxing lifts these constraints by permitting deprotection of a fraction of a tissue for testing while keeping the remaining of the sample intact for future analysis. After testing, the sample can be sent back to storage instead of being discarded, as is done in standard workflows. We achieve this microscale dewaxing by hydrodynamically confining nanoliter volumes of xylene on top of the sample with a probe head. We demonstrate micrometer-scale, chromogenic and fluorescence-based immunohistochemistry against multiple biomarkers (p53, CD45, HER2 and β-actin) on tonsil and breast tissue sections and microarrays. We achieve stain patterns as small as 100 μm × 50 μm as well as multiplexed immunostaining within a single tissue microarray core with a 20-fold time reduction for local dewaxing as compared to standard protocols. We also demonstrate a 10-fold reduction in the rehydration time, leading to lower processing times between different stains. We further show the potential of TL for retrospective studies by sequentially dewaxing and staining four individual cores within the same tissue microarray over four consecutive days. By combining tissue lithography with the concept of micro-immunohistochemistry, we implement each step of the IHC protocol—dewaxing, rehydration and staining—with the same microfluidic probe head. Tissue lithography brings a new level of versatility and flexibility in sample processing and budgeting in biobanks, which may alleviate current sample limitations for retrospective studies in biomarker discovery and drug screening.
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