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Pearce E, Wolley O, Mekhail SP, Gregory T, Gemmell NR, Oulton RF, Clark AS, Phillips CC, Padgett MJ. Single-frame transmission and phase imaging using off-axis holography with undetected photons. Sci Rep 2024; 14:16008. [PMID: 38992022 PMCID: PMC11239902 DOI: 10.1038/s41598-024-66233-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Accepted: 06/28/2024] [Indexed: 07/13/2024] Open
Abstract
Imaging with undetected photons relies upon nonlinear interferometry to extract the spatial image from an infrared probe beam and reveal it in the interference pattern of an easier-to-detect visible beam. Typically, the transmission and phase images are extracted using phase-shifting techniques and combining interferograms from multiple frames. Here we show that off-axis digital holography enables reconstruction of both transmission and phase images at the infrared wavelength from a single interferogram, and hence a single frame, recorded in the visible. This eliminates the need for phase stepping and multiple acquisitions, thereby greatly reducing total measurement time for imaging with long acquisition times at low flux or enabling video-rate imaging at higher flux. With this single-frame acquisition technique, we are able to reconstruct transmission images of an object in the infrared beam with a signal-to-noise ratio of 3.680 ± 0.004 at 10 frames per second, and record a dynamic scene in the infrared beam at 33 frames per second.
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Affiliation(s)
- Emma Pearce
- School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, UK
- Blackett Laboratory, Department of Physics, Imperial College London, London, SW7 2AZ, UK
| | - Osian Wolley
- School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Simon P Mekhail
- School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Thomas Gregory
- School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Nathan R Gemmell
- Blackett Laboratory, Department of Physics, Imperial College London, London, SW7 2AZ, UK
| | - Rupert F Oulton
- Blackett Laboratory, Department of Physics, Imperial College London, London, SW7 2AZ, UK
| | - Alex S Clark
- Quantum Engineering Technology Labs, H. H. Wills Physics Laboratory and Department of Electrical and Electronic Engineering, University of Bristol, BS8 1FD, Bristol, UK
| | - Chris C Phillips
- Blackett Laboratory, Department of Physics, Imperial College London, London, SW7 2AZ, UK
| | - Miles J Padgett
- School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, UK.
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2
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Picazo-Bueno JÁ, Ketelhut S, Schnekenburger J, Micó V, Kemper B. Off-axis digital lensless holographic microscopy based on spatially multiplexed interferometry. JOURNAL OF BIOMEDICAL OPTICS 2024; 29:S22715. [PMID: 39161785 PMCID: PMC11331263 DOI: 10.1117/1.jbo.29.s2.s22715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Revised: 06/23/2024] [Accepted: 07/17/2024] [Indexed: 08/21/2024]
Abstract
Significance Digital holographic microscopy (DHM) is a label-free microscopy technique that provides time-resolved quantitative phase imaging (QPI) by measuring the optical path delay of light induced by transparent biological samples. DHM has been utilized for various biomedical applications, such as cancer research and sperm cell assessment, as well as for in vitro drug or toxicity testing. Its lensless version, digital lensless holographic microscopy (DLHM), is an emerging technology that offers size-reduced, lightweight, and cost-effective imaging systems. These features make DLHM applicable, for example, in limited resource laboratories, remote areas, and point-of-care applications. Aim In addition to the abovementioned advantages, in-line arrangements for DLHM also include the limitation of the twin-image presence, which can restrict accurate QPI. We therefore propose a compact lensless common-path interferometric off-axis approach that is capable of quantitative imaging of fast-moving biological specimens, such as living cells in flow. Approach We suggest lensless spatially multiplexed interferometric microscopy (LESSMIM) as a lens-free variant of the previously reported spatially multiplexed interferometric microscopy (SMIM) concept. LESSMIM comprises a common-path interferometric architecture that is based on a single diffraction grating to achieve digital off-axis holography. From a series of single-shot off-axis holograms, twin-image free and time-resolved QPI is achieved by commonly used methods for Fourier filtering-based reconstruction, aberration compensation, and numerical propagation. Results Initially, the LESSMIM concept is experimentally demonstrated by results from a resolution test chart and investigations on temporal stability. Then, the accuracy of QPI and capabilities for imaging of living adherent cell cultures is characterized. Finally, utilizing a microfluidic channel, the cytometry of suspended cells in flow is evaluated. Conclusions LESSMIM overcomes several limitations of in-line DLHM and provides fast time-resolved QPI in a compact optical arrangement. In summary, LESSMIM represents a promising technique with potential biomedical applications for fast imaging such as in imaging flow cytometry or sperm cell analysis.
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Affiliation(s)
- José Ángel Picazo-Bueno
- University of Muenster, Biomedical Technology Center, Muenster, Germany
- University of Valencia, Department of Optics, Optometry and Vision Science, Burjassot, Spain
| | - Steffi Ketelhut
- University of Muenster, Biomedical Technology Center, Muenster, Germany
| | | | - Vicente Micó
- University of Valencia, Department of Optics, Optometry and Vision Science, Burjassot, Spain
| | - Björn Kemper
- University of Muenster, Biomedical Technology Center, Muenster, Germany
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3
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Long Z, Yuan Z, Fan X, He Z. Hyperspectral digital holography realized by using an electro-optical frequency comb via injection locking. OPTICS LETTERS 2024; 49:1516-1519. [PMID: 38489439 DOI: 10.1364/ol.516131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Accepted: 02/17/2024] [Indexed: 03/17/2024]
Abstract
Hyperspectral digital holography (HSDH) is a versatile holographic imaging technique that offers large unambiguous depth range and spectroscopic information. In this Letter, we propose a novel, to the best of our knowledge, HSDH system that is realized by using an electro-optical frequency comb (EOFC) via injection locking. In comparison with conventional dual-comb HSDH, the proposed system only requires one EOFC and few other devices, which not only simplifies the system structure and reduces the cost but also improves the imaging speed. We validated the system using an EOFC with 20 optical frequencies spaced at 18 GHz intervals. In a total measurement time of 0.5 s, we successfully captured images of two targets that were 0.74 mm apart without phase ambiguity and obtained the transmission spectrum of an absorbing gas simultaneously. This work provides valuable insights for HSDH systems relying on an optical frequency comb.
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Filan C, Green M, Diering A, Cicerone MT, Cheung LS, Kostka JE, Robles FE. Label-free functional analysis of root-associated microbes with dynamic quantitative oblique back-illumination microscopy. Sci Rep 2024; 14:5812. [PMID: 38461279 PMCID: PMC10925023 DOI: 10.1038/s41598-024-56443-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Accepted: 03/06/2024] [Indexed: 03/11/2024] Open
Abstract
The increasing global demand for food, coupled with concerns about the environmental impact of synthetic fertilizers, underscores the urgency of developing sustainable agricultural practices. Nitrogen-fixing bacteria, known as diazotrophs, offer a potential solution by converting atmospheric nitrogen into bioavailable forms, reducing the reliance on synthetic fertilizers. However, a deeper understanding of their interactions with plants and other microbes is needed. In this study, we introduce a recently developed label-free 3D quantitative phase imaging technology called dynamic quantitative oblique back-illumination microscopy (DqOBM) to assess the functional dynamic activity of diazotrophs in vitro and in situ. Our experiments involved three different diazotrophs (Sinorhizobium meliloti, Azotobacter vinelandii, and Rahnella aquatilis) cultured on media with amendments of carbon and nitrogen sources. Over 5 days, we observed increased dynamics in nutrient-amended media. These results suggest that the observed bacterial dynamics correlate with their metabolic activity. Furthermore, we applied qOBM to visualize microbial dynamics within the root cap and elongation zone of Arabidopsis thaliana primary roots. This allowed us to identify distinct areas of microbial infiltration in plant roots without the need for fluorescent markers. Our findings demonstrate that DqOBM can effectively characterize microbial dynamics and provide insights into plant-microbe interactions in situ, offering a valuable tool for advancing our understanding of sustainable agriculture.
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Affiliation(s)
- Caroline Filan
- George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, 30318, USA
| | - Madison Green
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, 30318, USA
| | - Abigail Diering
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Marcus T Cicerone
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Lily S Cheung
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Joel E Kostka
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, 30318, USA
| | - Francisco E Robles
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, 30318, USA.
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Jin L, Yu Z, Au A, Serles P, Wang N, Lant JT, Filleter T, Yip CM. P-TDHM: Open-source portable telecentric digital holographic microscope. HARDWAREX 2024; 17:e00508. [PMID: 38327674 PMCID: PMC10847153 DOI: 10.1016/j.ohx.2024.e00508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 12/12/2023] [Accepted: 01/19/2024] [Indexed: 02/09/2024]
Abstract
We present the design of a low-cost, portable telecentric digital holographic microscope (P-TDHM) that utilizes off-the-shelf components. We describe the system's hardware and software elements and evaluate its performance by imaging samples ranging from nano-printed targets to live HeLa cells, HEK293 cells, and Dolichospermum via both in-line and off-axis modes. Our results demonstrate that the system can acquire high quality quantitative phase images with nanometer axial and sub-micron lateral resolution in a small form factor, making it a promising candidate for resource-limited settings and remote locations. Our design represents a significant step forward in making telecentric digital holographic microscopy accessible and affordable to the broader community.
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Affiliation(s)
- Lei Jin
- Institute of Biomedical Engineering, 164 College St, University of Toronto, Toronto, ON M5S 3G9, Canada
- Donnelly Centre for Cellular & Biomolecular Research, University of Toronto, 160 College Street, Toronto, Ontario M5S 3E1, Canada
| | - Ziyang Yu
- Institute of Biomedical Engineering, 164 College St, University of Toronto, Toronto, ON M5S 3G9, Canada
- Donnelly Centre for Cellular & Biomolecular Research, University of Toronto, 160 College Street, Toronto, Ontario M5S 3E1, Canada
| | - Aaron Au
- Institute of Biomedical Engineering, 164 College St, University of Toronto, Toronto, ON M5S 3G9, Canada
- Donnelly Centre for Cellular & Biomolecular Research, University of Toronto, 160 College Street, Toronto, Ontario M5S 3E1, Canada
| | - Peter Serles
- Department of Mechanical and Industrial Engineering, 5 King's College Road, Toronto, ON M5S 3G8, Canada
| | - Nan Wang
- Civil and Environmental Engineering, 527 College Avenue, Cornell University, Ithaca, NY 14853, United States
| | - Jeremy T. Lant
- Donnelly Centre for Cellular & Biomolecular Research, University of Toronto, 160 College Street, Toronto, Ontario M5S 3E1, Canada
- Department of Chemistry, 80 St. George Street, Toronto, ON M5S 3H6, Canada
| | - Tobin Filleter
- Department of Mechanical and Industrial Engineering, 5 King's College Road, Toronto, ON M5S 3G8, Canada
| | - Christopher M. Yip
- Institute of Biomedical Engineering, 164 College St, University of Toronto, Toronto, ON M5S 3G9, Canada
- Donnelly Centre for Cellular & Biomolecular Research, University of Toronto, 160 College Street, Toronto, Ontario M5S 3E1, Canada
- Department of Chemical Engineering & Applied Chemistry, 200 College St, Toronto, ON M5S 3E5, Canada
- Department of Biochemistry, University of Toronto, 1 King's College Circle, Toronto, ON M5S 1A8, Canada
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6
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Kumar M, Murata T, Matoba O. Live Cell Imaging by Single-Shot Common-Path Wide Field-of-View Reflective Digital Holographic Microscope. SENSORS (BASEL, SWITZERLAND) 2024; 24:720. [PMID: 38339437 PMCID: PMC10857047 DOI: 10.3390/s24030720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Revised: 01/17/2024] [Accepted: 01/19/2024] [Indexed: 02/12/2024]
Abstract
Quantitative phase imaging by digital holographic microscopy (DHM) is a nondestructive and label-free technique that has been playing an indispensable role in the fields of science, technology, and biomedical imaging. The technique is competent in imaging and analyzing label-free living cells and investigating reflective surfaces. Herein, we introduce a new configuration of a wide field-of-view single-shot common-path off-axis reflective DHM for the quantitative phase imaging of biological cells that leverages several advantages, including being less-vibration sensitive to external perturbations due to its common-path configuration, also being compact in size, simple in optical design, highly stable, and cost-effective. A detailed description of the proposed DHM system, including its optical design, working principle, and capability for phase imaging, is presented. The applications of the proposed system are demonstrated through quantitative phase imaging results obtained from the reflective surface (USAF resolution test target) as well as transparent samples (living plant cells). The proposed system could find its applications in the investigation of several biological specimens and the optical metrology of micro-surfaces.
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Affiliation(s)
- Manoj Kumar
- Department of Systems Science, Graduate School of System Informatics, Kobe University, Rokkodai 1-1, Nada, Kobe 657-8501, Japan
- Center of Optical Scattering Image Science, Kobe University, Rokkodai 1-1, Nada, Kobe 657-8501, Japan
| | - Takashi Murata
- Department of Applied Bioscience, Kanagawa Institute of Technology, Atsugi 243-0292, Japan
| | - Osamu Matoba
- Department of Systems Science, Graduate School of System Informatics, Kobe University, Rokkodai 1-1, Nada, Kobe 657-8501, Japan
- Center of Optical Scattering Image Science, Kobe University, Rokkodai 1-1, Nada, Kobe 657-8501, Japan
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7
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Dwapanyin GO, Chow DJX, Tan TCY, Dubost NS, Morizet JM, Dunning KR, Dholakia K. Investigation of refractive index dynamics during in vitro embryo development using off-axis digital holographic microscopy. BIOMEDICAL OPTICS EXPRESS 2023; 14:3327-3342. [PMID: 37497510 PMCID: PMC10368053 DOI: 10.1364/boe.492292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 05/24/2023] [Accepted: 05/25/2023] [Indexed: 07/28/2023]
Abstract
Embryo quality is a crucial factor affecting live birth outcomes. However, an accurate diagnostic for embryo quality remains elusive in the in vitro fertilization clinic. Determining physical parameters of the embryo may offer key information for this purpose. Here, we demonstrate that digital holographic microscopy (DHM) can rapidly and non-invasively assess the refractive index of mouse embryos. Murine embryos were cultured in either low- or high-lipid containing media and digital holograms recorded at various stages of development. The phase of the recorded hologram was numerically retrieved, from which the refractive index of the embryo was calculated. We showed that DHM can detect spatio-temporal changes in refractive index during embryo development that are reflective of its lipid content. As accumulation of intracellular lipid is known to compromise embryo health, DHM may prove beneficial in developing an accurate, non-invasive, multimodal diagnostic.
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Affiliation(s)
- George O. Dwapanyin
- SUPA, School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews, Fife, United Kingdom
| | - Darren J. X. Chow
- Robinson Research Institute, School of Biomedicine, The University of Adelaide, Adelaide, Australia
- Australian Research Council Centre of Excellence for Nanoscale Biophotonics, The University of Adelaide, Adelaide, Australia
- Institute for Photonics and Advanced Sensing, The University of Adelaide, Adelaide, Australia
| | - Tiffany C. Y. Tan
- Robinson Research Institute, School of Biomedicine, The University of Adelaide, Adelaide, Australia
- Australian Research Council Centre of Excellence for Nanoscale Biophotonics, The University of Adelaide, Adelaide, Australia
- Institute for Photonics and Advanced Sensing, The University of Adelaide, Adelaide, Australia
| | - Nicolas S. Dubost
- SUPA, School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews, Fife, United Kingdom
| | - Josephine M. Morizet
- SUPA, School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews, Fife, United Kingdom
| | - Kylie R. Dunning
- Robinson Research Institute, School of Biomedicine, The University of Adelaide, Adelaide, Australia
- Australian Research Council Centre of Excellence for Nanoscale Biophotonics, The University of Adelaide, Adelaide, Australia
- Institute for Photonics and Advanced Sensing, The University of Adelaide, Adelaide, Australia
| | - Kishan Dholakia
- SUPA, School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews, Fife, United Kingdom
- School of Biological Sciences, The University of Adelaide, Adelaide, Australia
- Centre of Light for Life, The University of Adelaide, Adelaide, Australia
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8
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vom Werth KL, Kemper B, Kampmeier S, Mellmann A. Application of Digital Holographic Microscopy to Analyze Changes in T-Cell Morphology in Response to Bacterial Challenge. Cells 2023; 12:cells12050762. [PMID: 36899897 PMCID: PMC10000559 DOI: 10.3390/cells12050762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Revised: 02/16/2023] [Accepted: 02/24/2023] [Indexed: 03/06/2023] Open
Abstract
Quantitative phase imaging (QPI) is a non-invasive, label-free technique used to detect aberrant cell morphologies caused by disease, thus providing a useful diagnostic approach. Here, we evaluated the potential of QPI to differentiate specific morphological changes in human primary T-cells exposed to various bacterial species and strains. Cells were challenged with sterile bacterial determinants, i.e., membrane vesicles or culture supernatants, derived from different Gram-positive and Gram-negative bacteria. Timelapse QPI by digital holographic microscopy (DHM) was applied to capture changes in T-cell morphology over time. After numerical reconstruction and image segmentation, we calculated single cell area, circularity and mean phase contrast. Upon bacterial challenge, T-cells underwent rapid morphological changes such as cell shrinkage, alterations of mean phase contrast and loss of cell integrity. Time course and intensity of this response varied between both different species and strains. The strongest effect was observed for treatment with S. aureus-derived culture supernatants that led to complete lysis of the cells. Furthermore, cell shrinkage and loss of circular shape was stronger in Gram-negative than in Gram-positive bacteria. Additionally, T-cell response to bacterial virulence factors was concentration-dependent, as decreases in cellular area and circularity were enhanced with increasing concentrations of bacterial determinants. Our findings clearly indicate that T-cell response to bacterial stress depends on the causative pathogen, and specific morphological alterations can be detected using DHM.
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Affiliation(s)
| | - Björn Kemper
- Biomedical Technology Center of the Medical Faculty, University of Münster, 48149 Münster, Germany
| | - Stefanie Kampmeier
- Institute of Hygiene, University Hospital Münster, 48149 Münster, Germany
| | - Alexander Mellmann
- Institute of Hygiene, University Hospital Münster, 48149 Münster, Germany
- Correspondence: ; Tel.: +49-251-83-55361
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9
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Shin J, Kim G, Park J, Lee M, Park Y. Long-term label-free assessments of individual bacteria using three-dimensional quantitative phase imaging and hydrogel-based immobilization. Sci Rep 2023; 13:46. [PMID: 36593327 PMCID: PMC9806822 DOI: 10.1038/s41598-022-27158-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 12/27/2022] [Indexed: 01/03/2023] Open
Abstract
Three-dimensional (3D) quantitative phase imaging (QPI) enables long-term label-free tomographic imaging and quantitative analysis of live individual bacteria. However, the Brownian motion or motility of bacteria in a liquid medium produces motion artifacts during 3D measurements and hinders precise cell imaging and analysis. Meanwhile, existing cell immobilization methods produce noisy backgrounds and even alter cellular physiology. Here, we introduce a protocol that utilizes hydrogels for high-quality 3D QPI of live bacteria maintaining bacterial physiology. We demonstrate long-term high-resolution quantitative imaging and analysis of individual bacteria, including measuring the biophysical parameters of bacteria and responses to antibiotic treatments.
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Affiliation(s)
- Jeongwon Shin
- grid.37172.300000 0001 2292 0500Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141 South Korea
| | - Geon Kim
- grid.37172.300000 0001 2292 0500Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141 South Korea ,grid.37172.300000 0001 2292 0500KAIST Institute for Health Science and Technology, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141 South Korea
| | - Jinho Park
- grid.37172.300000 0001 2292 0500Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141 South Korea
| | - Moosung Lee
- grid.37172.300000 0001 2292 0500Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141 South Korea ,grid.37172.300000 0001 2292 0500KAIST Institute for Health Science and Technology, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141 South Korea
| | - YongKeun Park
- grid.37172.300000 0001 2292 0500Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141 South Korea ,grid.37172.300000 0001 2292 0500KAIST Institute for Health Science and Technology, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141 South Korea ,Tomocube Inc., Daejeon, 34051 South Korea
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10
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Label-free viability assay using in-line holographic video microscopy. Sci Rep 2022; 12:12746. [PMID: 35882977 PMCID: PMC9325748 DOI: 10.1038/s41598-022-17098-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Accepted: 07/20/2022] [Indexed: 01/05/2023] Open
Abstract
Total holographic characterization (THC) is presented here as an efficient, automated, label-free method of accurately identifying cell viability. THC is a single-particle characterization technology that determines the size and index of refraction of individual particles using the Lorenz-Mie theory of light scattering. Although assessment of cell viability is a challenge in many applications, including biologics manufacturing, traditional approaches often include unreliable labeling with dyes and/or time consuming methods of manually counting cells. In this work we measured the viability of Saccharomyces cerevisiae yeast in the presence of various concentrations of isopropanol as a function of time. All THC measurements were performed in the native environment of the sample with no dilution or addition of labels. Holographic measurements were made with an in-line holographic microscope using a 40[Formula: see text] objective lens with plane wave illumination. We compared our results with THC to manual counting of living and dead cells as distinguished with trypan blue dye. Our findings demonstrate that THC can effectively distinguish living and dead yeast cells by the index of refraction of individual cells.
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11
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Single-Shot 3D Topography of Transmissive and Reflective Samples with a Dual-Mode Telecentric-Based Digital Holographic Microscope. SENSORS 2022; 22:s22103793. [PMID: 35632202 PMCID: PMC9144696 DOI: 10.3390/s22103793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 05/12/2022] [Accepted: 05/13/2022] [Indexed: 02/01/2023]
Abstract
Common path DHM systems are the most robust DHM systems as they are based on self-interference and are thus less prone to external fluctuations. A common issue amongst these DHM systems is that the two replicas of the sample’s information overlay due to self-interference, making them only suitable for imaging sparse samples. This overlay has restricted the use of common-path DHM systems in material science. The overlay can be overcome by limiting the sample’s field of view to occupy only half of the imaging field of view or by using an optical spatial filter. In this work, we have implemented optical spatial filtering in a common-path DHM system using a Fresnel biprism. We have analyzed the optimal pinhole size by evaluating the frequency content of the reconstructed phase images of a star target. We have also measured the accuracy of the system and the sensitivity to noise for different pinhole sizes. Finally, we have proposed the first dual-mode common-path DHM system using a Fresnel biprism. The performance of the dual-model DHM system has been evaluated experimentally using transmissive and reflective microscopic samples.
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Digital Holographic Microscopy for Label-Free Detection of Leukocyte Alternations Associated with Perioperative Inflammation after Cardiac Surgery. Cells 2022; 11:cells11040755. [PMID: 35203403 PMCID: PMC8869820 DOI: 10.3390/cells11040755] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Revised: 02/16/2022] [Accepted: 02/19/2022] [Indexed: 02/05/2023] Open
Abstract
In a prospective observational pilot study on patients undergoing elective cardiac surgery with cardiopulmonary bypass, we evaluated label-free quantitative phase imaging (QPI) with digital holographic microscopy (DHM) to describe perioperative inflammation by changes in biophysical cell properties of lymphocytes and monocytes. Blood samples from 25 patients were investigated prior to cardiac surgery and postoperatively at day 1, 3 and 6. Biophysical and morphological cell parameters accessible with DHM, such as cell volume, refractive index, dry mass, and cell shape related form factor, were acquired and compared to common flow cytometric blood cell markers of inflammation and selected routine laboratory parameters. In all examined patients, cardiac surgery induced an acute inflammatory response as indicated by changes in routine laboratory parameters and flow cytometric cell markers. DHM results were associated with routine laboratory and flow cytometric data and correlated with complications in the postoperative course. In a subgroup analysis, patients were classified according to the inflammation related C-reactive protein (CRP) level, treatment with epinephrine and the occurrence of postoperative complications. Patients with regular courses, without epinephrine treatment and with low CRP values showed a postoperative lymphocyte volume increase. In contrast, the group of patients with increased CRP levels indicated an even further enlarged lymphocyte volume, while for the groups of epinephrine treated patients and patients with complicative courses, no postoperative lymphocyte volume changes were detected. In summary, the study demonstrates the capability of DHM to describe biophysical cell parameters of perioperative lymphocytes and monocytes changes in cardiac surgery patients. The pattern of correlations between biophysical DHM data and laboratory parameters, flow cytometric cell markers, and the postoperative course exemplify DHM as a promising diagnostic tool for a characterization of inflammatory processes and course of disease.
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13
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Eder KM, Marzi A, Barroso Á, Ketelhut S, Kemper B, Schnekenburger J. Label-Free Digital Holographic Microscopy for In Vitro Cytotoxic Effect Quantification of Organic Nanoparticles. Cells 2022; 11:cells11040644. [PMID: 35203295 PMCID: PMC8870653 DOI: 10.3390/cells11040644] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 02/10/2022] [Accepted: 02/11/2022] [Indexed: 02/07/2023] Open
Abstract
Cytotoxicity quantification of nanoparticles is commonly performed by biochemical assays to evaluate their biocompatibility and safety. We explored quantitative phase imaging (QPI) with digital holographic microscopy (DHM) as a time-resolved in vitro assay to quantify effects caused by three different types of organic nanoparticles in development for medical use. Label-free proliferation quantification of native cell populations facilitates cytotoxicity testing in biomedical nanotechnology. Therefore, DHM quantitative phase images from measurements on nanomaterial and control agent incubated cells were acquired over 24 h, from which the temporal course of the cellular dry mass was calculated within the observed field of view. The impact of LipImage™ 815 lipidots® nanoparticles, as well as empty and cabazitaxel-loaded poly(alkyl cyanoacrylate) nanoparticles on the dry mass development of four different cell lines (RAW 264.7, NIH-3T3, NRK-52E, and RLE-6TN), was observed vs. digitonin as cytotoxicity control and cells in culture medium. The acquired QPI data were compared to a colorimetric cell viability assay (WST-8) to explore the use of the DHM assay with standard biochemical analysis methods downstream. Our results show that QPI with DHM is highly suitable to identify harmful or low-toxic nanomaterials. The presented DHM assay can be implemented with commercial microscopes. The capability for imaging of native cells and the compatibility with common 96-well plates allows high-throughput systems and future embedding into existing experimental routines for in vitro cytotoxicity assessment.
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Bélanger E, Benadiba C, Rioux-Pellerin É, Becq F, Jourdain P, Marquet P. Engineered fluidic device to achieve multiplexed monitoring of cell cultures with digital holographic microscopy. OPTICS EXPRESS 2022; 30:414-426. [PMID: 35201218 DOI: 10.1364/oe.444701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 11/13/2021] [Indexed: 06/14/2023]
Abstract
We present a low-cost, 3D-printed, and biocompatible fluidic device, engineered to produce laminar and homogeneous flow over a large field-of-view. Such a fluidic device allows us to perform multiplexed temporal monitoring of cell cultures compatible with the use of various pharmacological protocols. Therefore, specific properties of each of the observed cell cultures can be discriminated simultaneously during the same experiment. This was illustrated by monitoring the agonists-mediated cellular responses, with digital holographic microscopy, of four different cell culture models of cystic fibrosis. Quantitatively speaking, this multiplexed approach provides a time saving factor of around four to reveal specific cellular features.
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15
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Roadmap on Digital Holography-Based Quantitative Phase Imaging. J Imaging 2021; 7:jimaging7120252. [PMID: 34940719 PMCID: PMC8703719 DOI: 10.3390/jimaging7120252] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 11/11/2021] [Accepted: 11/15/2021] [Indexed: 12/02/2022] Open
Abstract
Quantitative Phase Imaging (QPI) provides unique means for the imaging of biological or technical microstructures, merging beneficial features identified with microscopy, interferometry, holography, and numerical computations. This roadmap article reviews several digital holography-based QPI approaches developed by prominent research groups. It also briefly discusses the present and future perspectives of 2D and 3D QPI research based on digital holographic microscopy, holographic tomography, and their applications.
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16
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Javidi B, Carnicer A, Anand A, Barbastathis G, Chen W, Ferraro P, Goodman JW, Horisaki R, Khare K, Kujawinska M, Leitgeb RA, Marquet P, Nomura T, Ozcan A, Park Y, Pedrini G, Picart P, Rosen J, Saavedra G, Shaked NT, Stern A, Tajahuerce E, Tian L, Wetzstein G, Yamaguchi M. Roadmap on digital holography [Invited]. OPTICS EXPRESS 2021; 29:35078-35118. [PMID: 34808951 DOI: 10.1364/oe.435915] [Citation(s) in RCA: 64] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 09/04/2021] [Indexed: 05/22/2023]
Abstract
This Roadmap article on digital holography provides an overview of a vast array of research activities in the field of digital holography. The paper consists of a series of 25 sections from the prominent experts in digital holography presenting various aspects of the field on sensing, 3D imaging and displays, virtual and augmented reality, microscopy, cell identification, tomography, label-free live cell imaging, and other applications. Each section represents the vision of its author to describe the significant progress, potential impact, important developments, and challenging issues in the field of digital holography.
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17
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Vicar T, Chmelik J, Jakubicek R, Chmelikova L, Gumulec J, Balvan J, Provaznik I, Kolar R. Self-supervised pretraining for transferable quantitative phase image cell segmentation. BIOMEDICAL OPTICS EXPRESS 2021; 12:6514-6528. [PMID: 34745753 PMCID: PMC8547997 DOI: 10.1364/boe.433212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 08/03/2021] [Accepted: 08/24/2021] [Indexed: 06/13/2023]
Abstract
In this paper, a novel U-Net-based method for robust adherent cell segmentation for quantitative phase microscopy image is designed and optimised. We designed and evaluated four specific post-processing pipelines. To increase the transferability to different cell types, non-deep learning transfer with adjustable parameters is used in the post-processing step. Additionally, we proposed a self-supervised pretraining technique using nonlabelled data, which is trained to reconstruct multiple image distortions and improved the segmentation performance from 0.67 to 0.70 of object-wise intersection over union. Moreover, we publish a new dataset of manually labelled images suitable for this task together with the unlabelled data for self-supervised pretraining.
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Affiliation(s)
- Tomas Vicar
- Department of Biomedical Engineering, Faculty of Electrical Engineering and Communication, Brno University of Technology, Brno, Czech Republic
- Department of Pathological Physiology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Jiri Chmelik
- Department of Biomedical Engineering, Faculty of Electrical Engineering and Communication, Brno University of Technology, Brno, Czech Republic
| | - Roman Jakubicek
- Department of Biomedical Engineering, Faculty of Electrical Engineering and Communication, Brno University of Technology, Brno, Czech Republic
| | - Larisa Chmelikova
- Department of Biomedical Engineering, Faculty of Electrical Engineering and Communication, Brno University of Technology, Brno, Czech Republic
| | - Jaromir Gumulec
- Department of Pathological Physiology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Jan Balvan
- Department of Pathological Physiology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Ivo Provaznik
- Department of Biomedical Engineering, Faculty of Electrical Engineering and Communication, Brno University of Technology, Brno, Czech Republic
| | - Radim Kolar
- Department of Biomedical Engineering, Faculty of Electrical Engineering and Communication, Brno University of Technology, Brno, Czech Republic
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18
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Ryu D, Kim J, Lim D, Min HS, Yoo IY, Cho D, Park Y. Label-Free White Blood Cell Classification Using Refractive Index Tomography and Deep Learning. BME FRONTIERS 2021; 2021:9893804. [PMID: 37849908 PMCID: PMC10521749 DOI: 10.34133/2021/9893804] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Accepted: 06/29/2021] [Indexed: 10/19/2023] Open
Abstract
Objective and Impact Statement. We propose a rapid and accurate blood cell identification method exploiting deep learning and label-free refractive index (RI) tomography. Our computational approach that fully utilizes tomographic information of bone marrow (BM) white blood cell (WBC) enables us to not only classify the blood cells with deep learning but also quantitatively study their morphological and biochemical properties for hematology research. Introduction. Conventional methods for examining blood cells, such as blood smear analysis by medical professionals and fluorescence-activated cell sorting, require significant time, costs, and domain knowledge that could affect test results. While label-free imaging techniques that use a specimen's intrinsic contrast (e.g., multiphoton and Raman microscopy) have been used to characterize blood cells, their imaging procedures and instrumentations are relatively time-consuming and complex. Methods. The RI tomograms of the BM WBCs are acquired via Mach-Zehnder interferometer-based tomographic microscope and classified by a 3D convolutional neural network. We test our deep learning classifier for the four types of bone marrow WBC collected from healthy donors (n = 10 ): monocyte, myelocyte, B lymphocyte, and T lymphocyte. The quantitative parameters of WBC are directly obtained from the tomograms. Results. Our results show >99% accuracy for the binary classification of myeloids and lymphoids and >96% accuracy for the four-type classification of B and T lymphocytes, monocyte, and myelocytes. The feature learning capability of our approach is visualized via an unsupervised dimension reduction technique. Conclusion. We envision that the proposed cell classification framework can be easily integrated into existing blood cell investigation workflows, providing cost-effective and rapid diagnosis for hematologic malignancy.
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Affiliation(s)
- DongHun Ryu
- Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
- KAIST Institute for Health Science and Technology, KAIST, Daejeon 34141, Republic of Korea
| | - Jinho Kim
- Department of Health Sciences and Technology, Samsung Advanced Institute For Health Sciences and Technology, Sungkyunkwan University, Seoul 06355, Republic of Korea
| | - Daejin Lim
- Department of Health and Safety Convergence Science, Korea University, Seoul 02841, Republic of Korea
- Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 06351, Republic of Korea
| | | | - In Young Yoo
- Department of Laboratory Medicine, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul 06591, Republic of Korea
| | - Duck Cho
- Department of Health Sciences and Technology, Samsung Advanced Institute For Health Sciences and Technology, Sungkyunkwan University, Seoul 06355, Republic of Korea
- Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 06351, Republic of Korea
- Stem Cell & Regenerative Medicine Institute, Samsung Medical Center, Seoul 06531, Republic of Korea
| | - YongKeun Park
- KAIST Institute for Health Science and Technology, KAIST, Daejeon 34141, Republic of Korea
- Department of Health Sciences and Technology, Samsung Advanced Institute For Health Sciences and Technology, Sungkyunkwan University, Seoul 06355, Republic of Korea
- Tomocube, Inc., Daejeon 34051Republic of Korea
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19
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Kandel ME, Kim E, Lee YJ, Tracy G, Chung HJ, Popescu G. Multiscale Assay of Unlabeled Neurite Dynamics Using Phase Imaging with Computational Specificity. ACS Sens 2021; 6:1864-1874. [PMID: 33882232 PMCID: PMC8815662 DOI: 10.1021/acssensors.1c00100] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Primary neuronal cultures have been widely used to study neuronal morphology, neurophysiology, neurodegenerative processes, and molecular mechanism of synaptic plasticity underlying learning and memory. However, the unique behavioral properties of neurons make them challenging to study, with phenotypic differences expressed as subtle changes in neuronal arborization rather than easy-to-assay features such as cell count. The need to analyze morphology, growth, and intracellular transport has motivated the development of increasingly sophisticated microscopes and image analysis techniques. Due to its high-contrast, high-specificity output, many assays rely on confocal fluorescence microscopy, genetic methods, or antibody staining techniques. These approaches often limit the ability to measure quantitatively dynamic activity such as intracellular transport and growth. In this work, we describe a method for label-free live-cell cell imaging with antibody staining specificity by estimating the associated fluorescence signals via quantitative phase imaging and deep convolutional neural networks. This computationally inferred fluorescence image is then used to generate a semantic segmentation map, annotating subcellular compartments of live unlabeled neural cultures. These synthetic fluorescence maps were further applied to study the time-lapse development of hippocampal neurons, highlighting the relationships between the cellular dry mass production and the dynamic transport activity within the nucleus and neurites. Our implementation provides a high-throughput strategy to analyze neural network arborization dynamically, with high specificity and without the typical phototoxicity and photobleaching limitations associated with fluorescent markers.
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Affiliation(s)
- Mikhail E Kandel
- Beckman Institute, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Eunjae Kim
- Beckman Institute, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Young Jae Lee
- Beckman Institute, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
- Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Gregory Tracy
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana Champaign, Urbana, Illinois 61801, United States
| | - Hee Jung Chung
- Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana Champaign, Urbana, Illinois 61801, United States
| | - Gabriel Popescu
- Beckman Institute, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
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20
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Kumar M, Matoba O, Quan X, Rajput SK, Awatsuji Y, Tamada Y. Single-shot common-path off-axis digital holography: applications in bioimaging and optical metrology [Invited]. APPLIED OPTICS 2021; 60:A195-A204. [PMID: 33690370 DOI: 10.1364/ao.404208] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 10/15/2020] [Indexed: 06/12/2023]
Abstract
The demand for single-shot and common-path holographic systems has become increasingly important in recent years, as such systems offer various advantages compared to their counterparts. Single-shot holographic systems, for example, reduce computational complexity as only a single hologram with the object information required to process, making them more suitable for the investigation of dynamic events; and common-path holographic systems are less vibration-sensitive, compact, inexpensive, and high in temporal phase stability. We have developed a single-shot common-path off-axis digital holographic setup based on a beam splitter and pinhole. In this paper, we present a concise review of the proposed digital holographic system for several applications, including the quantitative phase imaging to investigate the morphological and quantitative parameters, as a metrological tool for testing of micro-optics, industrial inspection and measurement, and sound field imaging and visualization.
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21
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Kwee E, Peterson A, Halter M, Elliott J. Practical application of microsphere samples for benchmarking a quantitative phase imaging system. Cytometry A 2020; 99:1022-1032. [PMID: 33305901 PMCID: PMC8195315 DOI: 10.1002/cyto.a.24291] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 11/11/2020] [Accepted: 12/01/2020] [Indexed: 01/12/2023]
Abstract
Quantitative phase imaging (QPI) provides an approach for monitoring the dry mass of individual cells by measuring the optical pathlength of visible light as it passes through cells. A distinct advantage of QPI is that the measurements result in optical path length quantities that are, in principle, instrument independent. Reference materials that induce a well‐defined optical pathlength shift and are compatible with QPI imaging systems will be valuable in assuring the accuracy of such measurements on different instruments. In this study, we evaluate seven combinations of microspheres embedded in index refraction matching media as candidate reference materials for benchmarking the performance of a QPI system and as calibration standards for the optical pathlength measurement. Poly(methyl metharylate) microspheres and mineral oil were used to evaluate the range of illumination apertures, signal‐to‐noise ratios, and focus positions that allow an accurate quantitative optical pathlength measurement. The microsphere‐based reference material can be used to verify settings on an instrument that are suitable for obtaining an accurate pathlength measurement from biological cells. The microsphere/media reference material is applied to QPI‐based dry mass measurements of a population of HEK293 cells to benchmark and provide evidence that the QPI image data are accurate.
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Affiliation(s)
- Edward Kwee
- Biosystems and Biomaterials Division, National Institute of Standards and Technology, Gaithersburg, Maryland, USA
| | - Alexander Peterson
- Biosystems and Biomaterials Division, National Institute of Standards and Technology, Gaithersburg, Maryland, USA
| | - Michael Halter
- Biosystems and Biomaterials Division, National Institute of Standards and Technology, Gaithersburg, Maryland, USA
| | - John Elliott
- Biosystems and Biomaterials Division, National Institute of Standards and Technology, Gaithersburg, Maryland, USA
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22
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Cohen-Maslaton S, Barnea I, Taieb A, Shaked NT. Cell and nucleus refractive-index mapping by interferometric phase microscopy and rapid confocal fluorescence microscopy. JOURNAL OF BIOPHOTONICS 2020; 13:e202000117. [PMID: 32468735 DOI: 10.1002/jbio.202000117] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 05/06/2020] [Accepted: 05/21/2020] [Indexed: 05/12/2023]
Abstract
We present a multimodal technique for measuring the integral refractive index and the thickness of biological cells and their organelles by integrating interferometric phase microscopy (IPM) and rapid confocal fluorescence microscopy. First, the actual thickness maps of the cellular compartments are reconstructed using the confocal fluorescent sections, and then the optical path difference (OPD) map of the same cell is reconstructed using IPM. Based on the co-registered data, the integral refractive index maps of the cell and its organelles are calculated. This technique enables rapidly measuring refractive index of live, dynamic cells, where IPM provides quantitative imaging capabilities and confocal fluorescence microscopy provides molecular specificity of the cell organelles. We acquire human colorectal adenocarcinoma cells and show that the integral refractive index values are similar for the whole cell, the cytoplasm and the nucleus on the population level, but significantly different on the single cell level.
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Affiliation(s)
- Shir Cohen-Maslaton
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv, Israel
| | - Itay Barnea
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv, Israel
| | - Almog Taieb
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv, Israel
| | - Natan T Shaked
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv, Israel
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23
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Kolonko AK, Bangel-Ruland N, Goycoolea FM, Weber WM. Chitosan Nanocomplexes for the Delivery of ENaC Antisense Oligonucleotides to Airway Epithelial Cells. Biomolecules 2020; 10:biom10040553. [PMID: 32260534 PMCID: PMC7226018 DOI: 10.3390/biom10040553] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 03/31/2020] [Accepted: 04/04/2020] [Indexed: 12/11/2022] Open
Abstract
Nanoscale drug delivery systems exhibit a broad range of applications and promising treatment possibilities for various medical conditions. Nanomedicine is of great interest, particularly for rare diseases still lacking a curative treatment such as cystic fibrosis (CF). CF is defined by a lack of Cl− secretion through the cystic fibrosis transmembrane conductance regulator (CFTR) and an increased Na+ absorption mediated by the epithelial sodium channel (ENaC). The imbalanced ion and water transport leads to pathological changes in many organs, particularly in the lung. We developed a non-viral delivery system based on the natural aminopolysaccharide chitosan (CS) for the transport of antisense oligonucleotides (ASO) against ENaC to specifically address Na+ hyperabsorption. CS–ASO electrostatic self-assembled nanocomplexes were formed at varying positive/negative (P/N) charge ratios and characterized for their physicochemical properties. Most promising nanocomplexes (P/N 90) displayed an average size of ~150 nm and a zeta potential of ~+30 mV. Successful uptake of the nanocomplexes by the human airway epithelial cell line NCI-H441 was confirmed by fluorescence microscopy. Functional Ussing chamber measurements of transfected NCI-H441 cells showed significantly decreased Na+ currents, indicating successful downregulation of ENaC. The results obtained confirm the promising characteristics of CS as a non-viral and non-toxic delivery system and demonstrate the encouraging possibility to target ENaC with ASOs to treat abnormal ion transport in CF.
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Affiliation(s)
- A. Katharina Kolonko
- Institute of Animal Physiology, University of Muenster, Schlossplatz 8, 48143 Muenster, Germany; (N.B.-R.); (W.-M.W.)
- Correspondence: ; Tel.: +49-251-832-1784
| | - Nadine Bangel-Ruland
- Institute of Animal Physiology, University of Muenster, Schlossplatz 8, 48143 Muenster, Germany; (N.B.-R.); (W.-M.W.)
| | | | - Wolf-Michael Weber
- Institute of Animal Physiology, University of Muenster, Schlossplatz 8, 48143 Muenster, Germany; (N.B.-R.); (W.-M.W.)
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24
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Quantitative Phase Imaging Using Digital Holographic Microscopy Reliably Assesses Morphology and Reflects Elastic Properties of Fibrotic Intestinal Tissue. Sci Rep 2019; 9:19388. [PMID: 31852983 PMCID: PMC6920451 DOI: 10.1038/s41598-019-56045-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Accepted: 12/02/2019] [Indexed: 12/13/2022] Open
Abstract
Intestinal strictures are a frequent complication in patients with Crohn’s Disease (CD) and the presence of fibrosis within strictures impacts the therapeutic treatment approach. Here, we evaluate quantitative phase imaging (QPI) using digital holographic microscopy (DHM) for the evaluation of fibrosis within CD strictures. 30 full thickness resection specimens were obtained from non-stenotic and stenotic tissue areas of 15 CD patients. Cryostat sections were analyzed by DHM to measure the spatial distribution of the refractive index (RI) to quantify tissue density. Complementary, histopathological evaluation of H&E staining and immunofluorescence (IF) targeting fibrosis markers served as the gold standard. Moreover, tissue stiffness was evaluated by elastography. RI values assessed by DHM were significantly higher in stenotic compared to non-stenotic tissue areas (p < 0.001). Histopathological analysis using H&E staining and IF confirmed the elevated expression of fibrosis markers in stenotic compared to non-stenotic tissue (all p < 0.001). The RI retrieved by DHM strongly correlated with the amount of fibrosis as determined by IF (p < 0.001; R2 = 0.48). Furthermore, elastography detected a significantly higher tissue stiffness in stenotic as compared to non-stenotic tissue sections (p < 0.001). In conclusion, QPI using DHM accurately assesses fibrotic properties of CD-associated strictures and may improve the characterization of CD strictures.
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25
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Kandel ME, Hu C, Naseri Kouzehgarani G, Min E, Sullivan KM, Kong H, Li JM, Robson DN, Gillette MU, Best-Popescu C, Popescu G. Epi-illumination gradient light interference microscopy for imaging opaque structures. Nat Commun 2019; 10:4691. [PMID: 31619681 PMCID: PMC6795907 DOI: 10.1038/s41467-019-12634-3] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Accepted: 09/17/2019] [Indexed: 02/06/2023] Open
Abstract
Multiple scattering and absorption limit the depth at which biological tissues can be imaged with light. In thick unlabeled specimens, multiple scattering randomizes the phase of the field and absorption attenuates light that travels long optical paths. These obstacles limit the performance of transmission imaging. To mitigate these challenges, we developed an epi-illumination gradient light interference microscope (epi-GLIM) as a label-free phase imaging modality applicable to bulk or opaque samples. Epi-GLIM enables studying turbid structures that are hundreds of microns thick and otherwise opaque to transmitted light. We demonstrate this approach with a variety of man-made and biological samples that are incompatible with imaging in a transmission geometry: semiconductors wafers, specimens on opaque and birefringent substrates, cells in microplates, and bulk tissues. We demonstrate that the epi-GLIM data can be used to solve the inverse scattering problem and reconstruct the tomography of single cells and model organisms.
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Affiliation(s)
- Mikhail E Kandel
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Beckman Institute, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Chenfei Hu
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Beckman Institute, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Ghazal Naseri Kouzehgarani
- Beckman Institute, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Eunjung Min
- Rowland Institute at Harvard University, Cambridge, Cambridge, MA, USA
| | | | - Hyunjoon Kong
- Beckman Institute, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Car R. Woese Institute for Genomic Biology, University of Illinois at Urbana-, Champaign, IL, USA
| | - Jennifer M Li
- Rowland Institute at Harvard University, Cambridge, Cambridge, MA, USA
| | - Drew N Robson
- Rowland Institute at Harvard University, Cambridge, Cambridge, MA, USA
| | - Martha U Gillette
- Beckman Institute, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Department of Cell & Developmental Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Catherine Best-Popescu
- Beckman Institute, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Gabriel Popescu
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
- Beckman Institute, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
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26
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Kheireddine S, Smith ZJ, Nicolau DV, Wachsmann-Hogiu S. Simple adaptive mobile phone screen illumination for dual phone differential phase contrast (DPDPC) microscopy. BIOMEDICAL OPTICS EXPRESS 2019; 10:4369-4380. [PMID: 31565495 PMCID: PMC6757485 DOI: 10.1364/boe.10.004369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Revised: 07/11/2019] [Accepted: 07/18/2019] [Indexed: 05/03/2023]
Abstract
Phase contrast imaging is widely employed in the physical, biological, and medical sciences. However, typical implementations involve complex imaging systems that amount to in-line interferometers. We adapt differential phase contrast (DPC) to a dual-phone illumination-imaging system to obtain phase contrast images on a portable mobile phone platform. In this dual phone differential phase contrast (dpDPC) microscope, semicircles are projected sequentially on the display of one phone, and images are captured using a low-cost, short focal length lens attached to the second phone. By numerically combining images obtained using these semicircle patterns, high quality DPC images with ≈ 2 micrometer resolution can be easily acquired with no specialized hardware, circuitry, or instrument control programs.
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Affiliation(s)
- Sara Kheireddine
- Department of Bioengineering, McGill University, Montreal, Quebec, H3A 0E9, Canada
| | - Zachary J. Smith
- Department of Precision Machinery and Precision Instrumentation, University of Science and Technology of China, Hefei, China
| | - Dan V. Nicolau
- Department of Bioengineering, McGill University, Montreal, Quebec, H3A 0E9, Canada
| | - Sebastian Wachsmann-Hogiu
- Department of Bioengineering, McGill University, Montreal, Quebec, H3A 0E9, Canada
- Department of Pathology and Laboratory Medicine, University of California Davis, Davis, CA 95616, USA
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27
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Min J, Yao B, Trendafilova V, Ketelhut S, Kastl L, Greve B, Kemper B. Quantitative phase imaging of cells in a flow cytometry arrangement utilizing Michelson interferometer-based off-axis digital holographic microscopy. JOURNAL OF BIOPHOTONICS 2019; 12:e201900085. [PMID: 31169960 DOI: 10.1002/jbio.201900085] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Revised: 05/13/2019] [Accepted: 06/04/2019] [Indexed: 05/23/2023]
Abstract
We combined Michelson-interferometer-based off-axis digital holographic microscopy (DHM) with a common flow cytometry (FCM) arrangement. Utilizing object recognition procedures and holographic autofocusing during the numerical reconstruction of the acquired off-axis holograms, sharply focused quantitative phase images of suspended cells in flow were retrieved without labeling, from which biophysical cellular features of distinct cells, such as cell radius, refractive index and dry mass, can be subsequently retrieved in an automated manner. The performance of the proposed concept was first characterized by investigations on microspheres that were utilized as test standards. Then, we analyzed two types of pancreatic tumor cells with different morphology to further verify the applicability of the proposed method for quantitative live cell imaging. The retrieved biophysical datasets from cells in flow are found in good agreement with results from comparative investigations with previously developed DHM methods under static conditions, which demonstrates the effectiveness and reliability of our approach. Our results contribute to the establishment of DHM in imaging FCM and prospect to broaden the application spectrum of FCM by providing complementary quantitative imaging as well as additional biophysical cell parameters which are not accessible in current high-throughput FCM measurements.
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Affiliation(s)
- Junwei Min
- Biomedical Technology Center, University of Muenster, Muenster, Germany
- State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China
| | - Baoli Yao
- State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, China
| | | | - Steffi Ketelhut
- Biomedical Technology Center, University of Muenster, Muenster, Germany
| | - Lena Kastl
- Biomedical Technology Center, University of Muenster, Muenster, Germany
| | - Burkhard Greve
- Department of Radiotherapy-Radiooncology-, University Hospital Muenster, Muenster, Germany
| | - Björn Kemper
- Biomedical Technology Center, University of Muenster, Muenster, Germany
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28
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Amann S, Witzleben MV, Breuer S. 3D-printable portable open-source platform for low-cost lens-less holographic cellular imaging. Sci Rep 2019; 9:11260. [PMID: 31375772 PMCID: PMC6677730 DOI: 10.1038/s41598-019-47689-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Accepted: 07/22/2019] [Indexed: 02/06/2023] Open
Abstract
Digital holographic microscopy is an emerging, potentially low-cost alternative to conventional light microscopy for micro-object imaging on earth, underwater and in space. Immediate access to micron-scale objects however requires a well-balanced system design and sophisticated reconstruction algorithms, that are commercially available, however not accessible cost-efficiently. Here, we present an open-source implementation of a lens-less digital inline holographic microscope platform, based on off-the-shelf optical, electronic and mechanical components, costing less than $190. It employs a Blu-Ray semiconductor-laser-pickup or a light-emitting-diode, a pinhole, a 3D-printed housing consisting of 3 parts and a single-board portable computer and camera with an open-source implementation of the Fresnel-Kirchhoff routine. We demonstrate 1.55 μm spatial resolution by laser-pickup and 3.91 μm by the light-emitting-diode source. The housing and mechanical components are 3D printed. Both printer and reconstruction software source codes are open. The light-weight microscope allows to image label-free micro-spheres of 6.5 μm diameter, human red-blood-cells of about 8 μm diameter as well as fast-growing plant Nicotiana-tabacum-BY-2 suspension cells with 50 μm sizes. The imaging capability is validated by imaging-contrast quantification involving a standardized test target. The presented 3D-printable portable open-source platform represents a fully-open design, low-cost modular and versatile imaging-solution for use in high- and low-resource areas of the world.
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Affiliation(s)
- Stephan Amann
- Institute for Applied Physics, Technische Universität Darmstadt, Schlossgartenstraße 7, 64289, Darmstadt, Germany
| | - Max von Witzleben
- Institute for Applied Physics, Technische Universität Darmstadt, Schlossgartenstraße 7, 64289, Darmstadt, Germany
| | - Stefan Breuer
- Institute for Applied Physics, Technische Universität Darmstadt, Schlossgartenstraße 7, 64289, Darmstadt, Germany.
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29
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Lam VK, Nguyen T, Phan T, Chung BM, Nehmetallah G, Raub CB. Machine Learning with Optical Phase Signatures for Phenotypic Profiling of Cell Lines. Cytometry A 2019; 95:757-768. [PMID: 31008570 DOI: 10.1002/cyto.a.23774] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Revised: 03/22/2019] [Accepted: 04/03/2019] [Indexed: 12/29/2022]
Abstract
Robust and reproducible profiling of cell lines is essential for phenotypic screening assays. The goals of this study were to determine robust and reproducible optical phase signatures of cell lines for classification with machine learning and to correlate optical phase parameters to motile behavior. Digital holographic microscopy (DHM) reconstructed phase maps of cells from two pairs of cancer and non-cancer cell lines. Seventeen image parameters were extracted from each cell's phase map, used for linear support vector machine learning, and correlated to scratch wound closure and Boyden chamber chemotaxis. The classification accuracy was between 90% and 100% for the six pairwise cell line comparisons. Several phase parameters correlated with wound closure rate and chemotaxis across the four cell lines. The level of cell confluence in culture affected phase parameters in all cell lines tested. Results indicate that optical phase features of cell lines are a robust set of quantitative data of potential utility for phenotypic screening and prediction of motile behavior. © 2019 International Society for Advancement of Cytometry.
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Affiliation(s)
- Van K Lam
- Department of Biomedical Engineering, The Catholic University of America, Washington, DC
| | - Thanh Nguyen
- Department of Electrical Engineering and Computer Science, The Catholic University of America, Washington, DC
| | - Thuc Phan
- Department of Electrical Engineering and Computer Science, The Catholic University of America, Washington, DC
| | - Byung-Min Chung
- Department of Biology, The Catholic University of America, Washington, DC
| | - George Nehmetallah
- Department of Electrical Engineering and Computer Science, The Catholic University of America, Washington, DC
| | - Christopher B Raub
- Department of Biomedical Engineering, The Catholic University of America, Washington, DC
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30
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Karandikar SH, Zhang C, Meiyappan A, Barman I, Finck C, Srivastava PK, Pandey R. Reagent-Free and Rapid Assessment of T Cell Activation State Using Diffraction Phase Microscopy and Deep Learning. Anal Chem 2019; 91:3405-3411. [PMID: 30741527 PMCID: PMC6423970 DOI: 10.1021/acs.analchem.8b04895] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
CD8+ T cells constitute an essential compartment of the adaptive immune system. During immune responses, naı̈ve T cells become functional, as they are primed with their cognate determinants by the antigen presenting cells. Current methods of identifying activated CD8+ T cells are laborious, time-consuming and expensive due to the extensive list of required reagents. Here, we demonstrate an optical imaging approach featuring quantitative phase imaging to distinguish activated CD8+ T cells from naı̈ve CD8+ T cells in a rapid and reagent-free manner. We measured the dry mass of live cells and employed transport-based morphometry to better understand their differential morphological attributes. Our results reveal that, upon activation, the dry cell mass of T cells increases significantly in comparison to that of unstimulated cells. By employing deep learning formalism, we are able to accurately predict the population ratios of unknown mixed population based on the acquired quantitative phase images. We envision that, with further refinement, this label-free method of T cell phenotyping will lead to a rapid and cost-effective platform for assaying T cell responses to candidate antigens in the near future.
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Affiliation(s)
- Sukrut Hemant Karandikar
- Department of Immunology, University of Connecticut School of Medicine, Farmington, Connecticut 06030, United States
| | - Chi Zhang
- Department of Mechanical Engineering, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Akilan Meiyappan
- Department of Mechanical Engineering, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Ishan Barman
- Department of Mechanical Engineering, Johns Hopkins University, Baltimore, Maryland 21218, United States
- Department of Oncology, Johns Hopkins University, Baltimore, Maryland 21287, United States
| | - Christine Finck
- Department of Surgery, Connecticut Children’s Medical Center, Harford, Connecticut United States
- Connecticut Children’s Innovation Center, University of Connecticut School of Medicine, Farmington, Connecticut 06032, United States
| | - Pramod Kumar Srivastava
- Department of Immunology, University of Connecticut School of Medicine, Farmington, Connecticut 06030, United States
- Carole and Ray Neag Comprehensive Cancer Center, University of Connecticut School of Medicine, Farmington, Connecticut 06030, United States
| | - Rishikesh Pandey
- Connecticut Children’s Innovation Center, University of Connecticut School of Medicine, Farmington, Connecticut 06032, United States
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31
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Mugnano M, Memmolo P, Miccio L, Grilli S, Merola F, Calabuig A, Bramanti A, Mazzon E, Ferraro P. In vitro cytotoxicity evaluation of cadmium by label-free holographic microscopy. JOURNAL OF BIOPHOTONICS 2018; 11:e201800099. [PMID: 30079614 DOI: 10.1002/jbio.201800099] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Revised: 07/17/2018] [Accepted: 08/01/2018] [Indexed: 05/04/2023]
Abstract
Among all environmental pollutants, the toxic heavy metal cadmium is considered as a human carcinogen. Cadmium may induce cell death by apoptosis in various cell types, although the underlying mechanisms are still unclear. In this paper we show how a label-free digital holography (DH)-based technique is able to quantify the evolution of key biophysical parameters of cells during the exposure to cadmium for the first time. Murine embryonic fibroblasts NIH 3T3 are chosen here as cellular model for studying the cadmium effects. The results demonstrate that DH is able to retrieve the temporal evolution of different key parameters such as cell volume, projected area, cell thickness and dry mass, thus providing a full quantitative characterization of the cell physical behaviour during cadmium exposure. Our results show that the label-free character of the technique would allow biologists to perform systematic and reliable studies on cell death process induced by cadmium and we believe that more in general this can be easily extended to others heavy metals, thus avoiding the time-consuming, expensive and invasive label-based procedures used nowadays in the field. In fact, pollution by heavy metals is severe issue that needs rapid and reliable methods to be settled.
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Affiliation(s)
- Martina Mugnano
- Department of Physical Sciences and Technologies of Matter (DSFTM), CNR, Institute of Applied Science & Intelligent Systems (CNR-ISASI), Pozzuoli, Italy
| | - Pasquale Memmolo
- Department of Physical Sciences and Technologies of Matter (DSFTM), CNR, Institute of Applied Science & Intelligent Systems (CNR-ISASI), Pozzuoli, Italy
| | - Lisa Miccio
- Department of Physical Sciences and Technologies of Matter (DSFTM), CNR, Institute of Applied Science & Intelligent Systems (CNR-ISASI), Pozzuoli, Italy
| | - Simonetta Grilli
- Department of Physical Sciences and Technologies of Matter (DSFTM), CNR, Institute of Applied Science & Intelligent Systems (CNR-ISASI), Pozzuoli, Italy
| | - Francesco Merola
- Department of Physical Sciences and Technologies of Matter (DSFTM), CNR, Institute of Applied Science & Intelligent Systems (CNR-ISASI), Pozzuoli, Italy
| | - Alejandro Calabuig
- Department of Physical Sciences and Technologies of Matter (DSFTM), CNR, Institute of Applied Science & Intelligent Systems (CNR-ISASI), Pozzuoli, Italy
| | - Alessia Bramanti
- Department of Physical Sciences and Technologies of Matter (DSFTM), CNR, Institute of Applied Science & Intelligent Systems (CNR-ISASI), Pozzuoli, Italy
- Department of Physical Sciences and Technologies of Matter (DSFTM), IRCCS Centre for Neuroscience Bonino-Pulejo, Messina, Italy
| | - Emanuela Mazzon
- Department of Physical Sciences and Technologies of Matter (DSFTM), IRCCS Centre for Neuroscience Bonino-Pulejo, Messina, Italy
| | - Pietro Ferraro
- Department of Physical Sciences and Technologies of Matter (DSFTM), CNR, Institute of Applied Science & Intelligent Systems (CNR-ISASI), Pozzuoli, Italy
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32
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Dannhauser D, Rossi D, Memmolo P, Finizio A, Ferraro P, Netti PA, Causa F. Biophysical investigation of living monocytes in flow by collaborative coherent imaging techniques. BIOMEDICAL OPTICS EXPRESS 2018; 9:5194-5204. [PMID: 30460122 PMCID: PMC6238935 DOI: 10.1364/boe.9.005194] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 09/21/2018] [Accepted: 09/23/2018] [Indexed: 05/17/2023]
Abstract
We implemented a completely label-free biophysical (morphometric and optical) property characterization of living monocytes in flow, using measurements obtained from two coherent imaging techniques: a pure light scattering approach to obtain an optical signature (OS) of cells, and a digital holography (DH) approach to achieve optical cell reconstructions in flow. A precise 3D cell alignment platform, taking advantage of viscoelastic fluid properties and microfluidic channel geometry, was used to investigate the OS of cells to achieve their refractive index, ratio of the nucleus over cytoplasm, and overall cell dimension. Further quantitative phase-contrast reconstructions by DH were employed to calculate surface area, dry mass, and biovolume of monocytes by using the OS outcomes as input parameters. The results show significantly different biophysical cell properties, confirming the possibility to differentiate monocytes from other cell classes in flow, thus avoiding chemical cell staining or labeling, which are nowadays used.
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Affiliation(s)
- David Dannhauser
- Center for Advanced Biomaterials for Health Care@CRIB, Istituto Italiano di Tecnologia, Largo Barsanti e Matteucci 53, 80125 Naples, Italy
| | - Domenico Rossi
- Center for Advanced Biomaterials for Health Care@CRIB, Istituto Italiano di Tecnologia, Largo Barsanti e Matteucci 53, 80125 Naples, Italy
| | - Pasquale Memmolo
- CNR-ISASI Institute of Applied Sciences & Intelligent Systems “E. Caianiello”, Via Campi Flegrei 34, 80078 Pozzuoli, Italy
| | - Andrea Finizio
- CNR-ISASI Institute of Applied Sciences & Intelligent Systems “E. Caianiello”, Via Campi Flegrei 34, 80078 Pozzuoli, Italy
| | - Pietro Ferraro
- CNR-ISASI Institute of Applied Sciences & Intelligent Systems “E. Caianiello”, Via Campi Flegrei 34, 80078 Pozzuoli, Italy
| | - Paolo Antonio Netti
- Center for Advanced Biomaterials for Health Care@CRIB, Istituto Italiano di Tecnologia, Largo Barsanti e Matteucci 53, 80125 Naples, Italy
- Interdisciplinary Research Centre on Biomaterials (CRIB) and Dipartimento di Ingegneria Chimica, dei Materiali e della Produzione Industriale (DICMAPI), Università degli Studi di Napoli “Federico II”, Piazzale Tecchio 80, 80125 Naples, Italy
| | - Filippo Causa
- Center for Advanced Biomaterials for Health Care@CRIB, Istituto Italiano di Tecnologia, Largo Barsanti e Matteucci 53, 80125 Naples, Italy
- Interdisciplinary Research Centre on Biomaterials (CRIB) and Dipartimento di Ingegneria Chimica, dei Materiali e della Produzione Industriale (DICMAPI), Università degli Studi di Napoli “Federico II”, Piazzale Tecchio 80, 80125 Naples, Italy
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33
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Shevkunov I, Katkovnik V, Petrov NV, Egiazarian K. Super-resolution microscopy for biological specimens: lensless phase retrieval in noisy conditions. BIOMEDICAL OPTICS EXPRESS 2018; 9:5511-5523. [PMID: 30460144 PMCID: PMC6238936 DOI: 10.1364/boe.9.005511] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 10/06/2018] [Accepted: 10/07/2018] [Indexed: 06/09/2023]
Abstract
The paper is devoted to a computational super-resolution microscopy. A complex-valued wavefront of a transparent biological cellular specimen is restored from multiple intensity diffraction patterns registered with noise. For this problem, the recently developed lensless super-resolution phase retrieval algorithm [Optica, 4(7), 786 (2017)] is modified and tuned. This algorithm is based on a random phase coding of the wavefront and on a sparse complex-domain approximation of the specimen. It is demonstrated in experiments, that the reliable phase and amplitude imaging of the specimen is achieved for the low signal-to-noise ratio provided a low dynamic range of observations. The filterings in the observation domain and specimen variables are specific features of the applied algorithm. If these filterings are omitted the algorithm becomes a super-resolution version of the standard iterative phase retrieval algorithms. In comparison with this simplified algorithm with no filterings, our algorithm shows a valuable improvement in imaging with much smaller number of observations and shorter exposure time. In this way, presented algorithm demonstrates ability to work in a low radiation photon-limited mode.
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Affiliation(s)
- Igor Shevkunov
- Department of Signal Processing, Tampere University of Technology,
Finland
- Department of Photonics and Optical Information Technology, ITMO University, St. Petersburg,
Russia
| | - Vladimir Katkovnik
- Department of Signal Processing, Tampere University of Technology,
Finland
| | - Nikolay V. Petrov
- Department of Photonics and Optical Information Technology, ITMO University, St. Petersburg,
Russia
| | - Karen Egiazarian
- Department of Signal Processing, Tampere University of Technology,
Finland
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34
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Zhang Y, Judson RL. Evaluation of holographic imaging cytometer holomonitor M4® motility applications. Cytometry A 2018; 93:1125-1131. [PMID: 30343513 DOI: 10.1002/cyto.a.23635] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 09/13/2018] [Accepted: 09/19/2018] [Indexed: 12/11/2022]
Abstract
Digital holographic cytometry (DHC) and other methods of quantitative phase imaging permit extended time-lapse imaging of mammalian cells in the absence of induced cellular toxicity. Manufactured DHC platforms equipped with semi-automated image acquisition, segmentation, and analysis software packages (or modules) for assessing cell behavior are now commercially available. When housed in mammalian cell incubators these cytometers offer the potential to monitor and quantify a range of cellular behaviors without disrupting routine culture. Realization of this potential requires validation against established standards. Two proprietary software modules for assessing cellular motility available using the HoloMonitor M4 DHC platform were evaluated on human melanoma cells lines with known relative motility and metastatic potential. One such software package, the Track Cells module, was run during routine culture. In addition, the Wound Healing module was conducted in parallel with established transwell migration and invasion assays. Each module was evaluated for reproducibility and correlation to established assays. Both software modules reliably recorded increased cellular motility in the metastatic 1205Lu line as compared with the non-metastatic WM793 line. In a direct comparison of the two propriety DHC software modules and two established transwell assays, the relative cell motilities were well correlated. The granularity of data provided by the Track Cells module permitted the additional identification of rare hyper-motile cells in the metastatic population and the distinction of motility from division associated displacement. The two HoloMonitor M4 DHC proprietary software modules for assessing cellular motility yielded reproducible results that were well-correlated with established standards. © 2018 International Society for Advancement of Cytometry.
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Affiliation(s)
- Yuntian Zhang
- Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, California, 94143.,Department of Dermatology, University of California San Francisco, San Francisco, California, 94115
| | - Robert L Judson
- Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, California, 94143.,Department of Dermatology, University of California San Francisco, San Francisco, California, 94115
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35
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Quantitative Phase Imaging for Label-Free Analysis of Cancer Cells—Focus on Digital Holographic Microscopy. APPLIED SCIENCES-BASEL 2018. [DOI: 10.3390/app8071027] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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36
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Ugele M, Weniger M, Leidenberger M, Huang Y, Bassler M, Friedrich O, Kappes B, Hayden O, Richter L. Label-free, high-throughput detection of P. falciparum infection in sphered erythrocytes with digital holographic microscopy. LAB ON A CHIP 2018; 18:1704-1712. [PMID: 29796511 DOI: 10.1039/c8lc00350e] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Effective malaria treatment requires rapid and accurate diagnosis of infecting species and actual parasitemia. Despite the recent success of rapid tests, the analysis of thick and thin blood smears remains the gold standard for routine malaria diagnosis in endemic areas. For non-endemic regions, sample preparation and analysis of blood smears are an issue due to low microscopy expertise and few cases of imported malaria. Automation of microscopy results could be beneficial to quickly confirm suspected infections in such conditions. Here, we present a label-free, high-throughput method for early malaria detection with the potential to reduce inter-observer variation by reducing sample preparation and analysis effort. We used differential digital holographic microscopy in combination with two-dimensional hydrodynamic focusing for the label-free detection of P. falciparum infection in sphered erythrocytes, with a parasitemia detection limit of 0.01%. Moreover, the achieved differentiation of P. falciparum ring-, trophozoite- and schizont life cycle stages in synchronized cultures demonstrates the potential for future discrimination of even malaria species.
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Affiliation(s)
- Matthias Ugele
- In-Vitro DX & Bioscience, Department of Strategy and Innovation, Siemens Healthcare GmbH, Günther-Scharowsky-Str. 1, 91058 Erlangen, Germany.
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37
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Mugnano M, Memmolo P, Miccio L, Merola F, Bianco V, Bramanti A, Gambale A, Russo R, Andolfo I, Iolascon A, Ferraro P. Label-Free Optical Marker for Red-Blood-Cell Phenotyping of Inherited Anemias. Anal Chem 2018; 90:7495-7501. [PMID: 29792684 DOI: 10.1021/acs.analchem.8b01076] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The gold-standard methods for anemia diagnosis are complete blood counts and peripheral-smear observations. However, these do not allow for a complete differential diagnosis as that requires biochemical assays, which are label-dependent techniques. On the other hand, recent studies focus on label-free quantitative phase imaging (QPI) of blood samples to investigate blood diseases by using video-based morphological methods. However, when sick cells are very similar to healthy ones in terms of morphometric features, identification of a blood disease becomes challenging even with QPI. Here, we introduce a label-free optical marker (LOM) to detect red-blood-cell (RBC) phenotypes, demonstrating that a single set of all-optical parameters can clearly identify a signature directly related to an erythrocyte disease through modeling each RBC as a biological lens. We tested this novel biophotonic analysis by proving that several inherited anemias, such as iron-deficiency anemia, thalassemia, hereditary spherocytosis, and congenital dyserythropoietic anemia, can be identified and sorted, thus opening a novel route for blood diagnosis on a completely different concept based on LOMs.
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Affiliation(s)
- Martina Mugnano
- Institute of Applied Sciences and Intelligent Systems, ISASI, "E. Caianiello" , CNR , Via Campi Flegrei 34 , 80078 Pozzuoli , NA , Italy
| | - Pasquale Memmolo
- Institute of Applied Sciences and Intelligent Systems, ISASI, "E. Caianiello" , CNR , Via Campi Flegrei 34 , 80078 Pozzuoli , NA , Italy
| | - Lisa Miccio
- Institute of Applied Sciences and Intelligent Systems, ISASI, "E. Caianiello" , CNR , Via Campi Flegrei 34 , 80078 Pozzuoli , NA , Italy
| | - Francesco Merola
- Institute of Applied Sciences and Intelligent Systems, ISASI, "E. Caianiello" , CNR , Via Campi Flegrei 34 , 80078 Pozzuoli , NA , Italy
| | - Vittorio Bianco
- Institute of Applied Sciences and Intelligent Systems, ISASI, "E. Caianiello" , CNR , Via Campi Flegrei 34 , 80078 Pozzuoli , NA , Italy
| | - Alessia Bramanti
- Institute of Applied Sciences and Intelligent Systems, ISASI, "E. Caianiello" , CNR , Via Campi Flegrei 34 , 80078 Pozzuoli , NA , Italy
| | - Antonella Gambale
- Department of Molecular Medicine and Medical Biotechnology , University of Naples Federico II & CEINGE - Advanced Biotechnologies , Via Gaetano Salvatore 486 , 80145 Napoli , Italy
| | - Roberta Russo
- Department of Molecular Medicine and Medical Biotechnology , University of Naples Federico II & CEINGE - Advanced Biotechnologies , Via Gaetano Salvatore 486 , 80145 Napoli , Italy
| | - Immacolata Andolfo
- Department of Molecular Medicine and Medical Biotechnology , University of Naples Federico II & CEINGE - Advanced Biotechnologies , Via Gaetano Salvatore 486 , 80145 Napoli , Italy
| | - Achille Iolascon
- Department of Molecular Medicine and Medical Biotechnology , University of Naples Federico II & CEINGE - Advanced Biotechnologies , Via Gaetano Salvatore 486 , 80145 Napoli , Italy
| | - Pietro Ferraro
- Institute of Applied Sciences and Intelligent Systems, ISASI, "E. Caianiello" , CNR , Via Campi Flegrei 34 , 80078 Pozzuoli , NA , Italy
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Müller P, Schürmann M, Girardo S, Cojoc G, Guck J. Accurate evaluation of size and refractive index for spherical objects in quantitative phase imaging. OPTICS EXPRESS 2018; 26:10729-10743. [PMID: 29716005 DOI: 10.1364/oe.26.010729] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Accepted: 03/28/2018] [Indexed: 06/08/2023]
Abstract
Measuring the average refractive index (RI) of spherical objects, such as suspended cells, in quantitative phase imaging (QPI) requires a decoupling of RI and size from the QPI data. This has been commonly achieved by determining the object's radius with geometrical approaches, neglecting light-scattering. Here, we present a novel QPI fitting algorithm that reliably uncouples the RI using Mie theory and a semi-analytical, corrected Rytov approach. We assess the range of validity of this algorithm in silico and experimentally investigate various objects (oil and protein droplets, microgel beads, cells) and noise conditions. In addition, we provide important practical cues for the analysis of spherical objects in QPI.
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39
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Kandel ME, Fanous M, Best-Popescu C, Popescu G. Real-time halo correction in phase contrast imaging. BIOMEDICAL OPTICS EXPRESS 2018; 9:623-635. [PMID: 29552399 PMCID: PMC5854064 DOI: 10.1364/boe.9.000623] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Revised: 12/24/2017] [Accepted: 12/24/2017] [Indexed: 05/19/2023]
Abstract
As a label-free, nondestructive method, phase contrast is by far the most popular microscopy technique for routine inspection of cell cultures. However, features of interest such as extensions near cell bodies are often obscured by a glow, which came to be known as the halo. Advances in modeling image formation have shown that this artifact is due to the limited spatial coherence of the illumination. Nevertheless, the same incoherent illumination is responsible for superior sensitivity to fine details in the phase contrast geometry. Thus, there exists a trade-off between high-detail (incoherent) and low-detail (coherent) imaging systems. In this work, we propose a method to break this dichotomy, by carefully mixing corrected low-frequency and high-frequency data in a way that eliminates the edge effect. Specifically, our technique is able to remove halo artifacts at video rates, requiring no manual interaction or a priori point spread function measurements. To validate our approach, we imaged standard spherical beads, sperm cells, tissue slices, and red blood cells. We demonstrate real-time operation with a time evolution study of adherent neuron cultures whose neurites are revealed by our halo correction. We show that with our novel technique, we can quantify cell growth in large populations, without the need for thresholds and system variant calibration.
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Affiliation(s)
- Mikhail E. Kandel
- Department of Electrical and Computer Engineering, the University of Illinois at Urbana-Champaign, 306 N. Wright Street, Urbana, IL 61801, USA
| | - Michael Fanous
- Department of Bioengineering, the University of Illinois at Urbana-Champaign, 306 N. Wright Street, Urbana, IL 61801, USA
| | - Catherine Best-Popescu
- Department of Bioengineering, the University of Illinois at Urbana-Champaign, 306 N. Wright Street, Urbana, IL 61801, USA
| | - Gabriel Popescu
- Department of Electrical and Computer Engineering, the University of Illinois at Urbana-Champaign, 306 N. Wright Street, Urbana, IL 61801, USA
- Department of Bioengineering, the University of Illinois at Urbana-Champaign, 306 N. Wright Street, Urbana, IL 61801, USA
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40
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Uttam S, Liu Y. Fourier phase based depth-resolved nanoscale nuclear architecture mapping for cancer detection. Methods 2017; 136:134-151. [PMID: 29127043 DOI: 10.1016/j.ymeth.2017.10.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 10/29/2017] [Accepted: 10/31/2017] [Indexed: 10/18/2022] Open
Abstract
Quantitative phase imaging (QPI) modality has been widely adopted in a variety of applications ranging from identifying photomask defects in lithography to characterizing cell structure and tissue morphology in cancer. Traditional QPI utilizes the electromagnetic phase of transmitted light to measure, with nanometer scale sensitivity, alterations in the optical thickness of a sample of interest. In our work, the QPI paradigm is generalized to study depth-resolved properties of phase objects with slowly varying refractive index without a strong interface by utilizing the Fourier phase associated with Fourier-domain optical coherence tomography (FD-OCT). Specifically, based on computing the Fourier phase of light back-scattered by cell nuclei, we have developed nanoscale nuclear architecture mapping (nanoNAM) method that quantifies, with nanoscale sensitivity, (a) the depth-resolved alterations in mean nuclear optical density, and (b) depth-resolved localized heterogeneity in optical density of the cell nuclei. We have used nanoNAM to detect malignant transformation in colon carcinogenesis, even in tissue that appears histologically normal according to pathologists, thereby showing its potential as a pathology aid in cases where pathology examination remains inconclusive, and for screening patient populations at risk of developing cancer. In this paper, we integrate all aspects of nanoNAM, from principle through instrumentation and analysis, to show that nanoNAM is a promising, low-cost, and label-free method for identifying pathologically indeterminate pre-cancerous and cancerous cells. Importantly, it can seamlessly integrate into the clinical pipeline by utilizing clinically prepared formalin-fixed, paraffin-embedded tissue sections.
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Affiliation(s)
- Shikhar Uttam
- Department of Computational and Systems Biology, University of Pittsburgh, Pittsburgh, PA, United States.
| | - Yang Liu
- Biomedical Optical Imaging Laboratory, Departments of Medicine and Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States; University of Pittsburgh Cancer Institute, Pittsburgh, PA, United States.
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41
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Cordeiro C, Abilez OJ, Goetz G, Gupta T, Zhuge Y, Solgaard O, Palanker D. Optophysiology of cardiomyocytes: characterizing cellular motion with quantitative phase imaging. BIOMEDICAL OPTICS EXPRESS 2017; 8:4652-4662. [PMID: 29082092 PMCID: PMC5654807 DOI: 10.1364/boe.8.004652] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 09/15/2017] [Accepted: 09/19/2017] [Indexed: 06/07/2023]
Abstract
Quantitative phase imaging enables precise characterization of cellular shape and motion. Variation of cell volume in populations of cardiomyocytes can help distinguish their types, while changes in optical thickness during beating cycle identify contraction and relaxation periods and elucidate cell dynamics. Parameters such as characteristic cycle shape, beating frequency, duration and regularity can be used to classify stem-cell derived cardiomyocytes according to their health and, potentially, cell type. Unlike classical patch-clamp based electrophysiological characterization of cardiomyocytes, this interferometric approach enables rapid and non-destructive analysis of large populations of cells, with longitudinal follow-up, and applications to tissue regeneration, personalized medicine, and drug testing.
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Affiliation(s)
- Christine Cordeiro
- Department of Electrical Engineering, Stanford University, Stanford, CA, 94305, USA
| | - Oscar J. Abilez
- Division of Cardiovascular Medicine, Stanford University, Stanford, CA, 94305, USA
- Cardiovascular Institute, Stanford University, Stanford, CA 94305, USA
| | - Georges Goetz
- Department of Neurosurgery, Stanford University, Stanford, CA, 94305, USA
| | - Tushar Gupta
- Department of Electrical Engineering, Stanford University, Stanford, CA, 94305, USA
| | - Yan Zhuge
- Molecular Imaging Program at Stanford, Stanford University, Stanford, CA, 94305, USA
| | - Olav Solgaard
- Department of Electrical Engineering, Stanford University, Stanford, CA, 94305, USA
| | - Daniel Palanker
- Department of Ophthalmology, Stanford University, Stanford, CA, 94305, USA
- Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA, 94305, USA
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42
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Label-free characterization of ultra violet-radiation-induced changes in skin fibroblasts with Raman spectroscopy and quantitative phase microscopy. Sci Rep 2017; 7:10829. [PMID: 28883655 PMCID: PMC5589874 DOI: 10.1038/s41598-017-11091-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 08/17/2017] [Indexed: 11/09/2022] Open
Abstract
Minimizing morbidities and mortalities associated with skin cancers requires sustained research with the goal of obtaining fresh insights into disease onset and progression under specific stimuli, particularly the influence of ultraviolet rays. In the present study, label-free profiling of skin fibroblasts exposed to time-bound ultra-violet radiation has been performed using quantitative phase imaging and Raman spectroscopy. Statistically significant differences in quantifiable biophysical parameters, such as matter density and cell dry mass, were observed with phase imaging. Accurate estimation of changes in the biochemical constituents, notably nucleic acids and proteins, was demonstrated through a combination of Raman spectroscopy and multivariate analysis of spectral patterns. Overall, the findings of this study demonstrate the promise of these non-perturbative optical modalities in accurately identifying cellular phenotypes and responses to external stimuli by combining molecular and biophysical information.
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