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Kim JH, Cetinkaya-Fisgin A, Zahn N, Sari MC, Hoke A, Barman I. Label-Free Visualization and Morphological Profiling of Neuronal Differentiation and Axonal Degeneration through Quantitative Phase Imaging. Adv Biol (Weinh) 2024; 8:e2400020. [PMID: 38548657 PMCID: PMC11090721 DOI: 10.1002/adbi.202400020] [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: 03/13/2024] [Indexed: 05/15/2024]
Abstract
Understanding the intricate processes of neuronal growth, degeneration, and neurotoxicity is paramount for unraveling nervous system function and holds significant promise in improving patient outcomes, especially in the context of chemotherapy-induced peripheral neuropathy (CIPN). These processes are influenced by a broad range of entwined events facilitated by chemical, electrical, and mechanical signals. The progress of each process is inherently linked to phenotypic changes in cells. Currently, the primary means of demonstrating morphological changes rely on measurements of neurite outgrowth and axon length. However, conventional techniques for monitoring these processes often require extensive preparation to enable manual or semi-automated measurements. Here, a label-free and non-invasive approach is employed for monitoring neuronal differentiation and degeneration using quantitative phase imaging (QPI). Operating on unlabeled specimens and offering little to no phototoxicity and photobleaching, QPI delivers quantitative maps of optical path length delays that provide an objective measure of cellular morphology and dynamics. This approach enables the visualization and quantification of axon length and other physical properties of dorsal root ganglion (DRG) neuronal cells, allowing greater understanding of neuronal responses to stimuli simulating CIPN conditions. This research paves new avenues for the development of more effective strategies in the clinical management of neurotoxicity.
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Affiliation(s)
- Jeong Hee Kim
- Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD, 21218, USA
| | - Aysel Cetinkaya-Fisgin
- Department of Neurology, Neuromuscular Division, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Noah Zahn
- Department Chemical & Biomolecular Engineering, Johns Hopkins University, Baltimore, MD, 21218, USA
| | - Mehmet Can Sari
- Department of Neurology, Neuromuscular Division, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Ahmet Hoke
- Department of Neurology, Neuromuscular Division, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Ishan Barman
- Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD, 21218, USA
- Department of Oncology, The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
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2
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Burguete-Lopez A, Makarenko M, Bonifazi M, Menezes de Oliveira BN, Getman F, Tian Y, Mazzone V, Li N, Giammona A, Liberale C, Fratalocchi A. Real-time simultaneous refractive index and thickness mapping of sub-cellular biology at the diffraction limit. Commun Biol 2024; 7:154. [PMID: 38321111 PMCID: PMC10847501 DOI: 10.1038/s42003-024-05839-w] [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: 04/28/2023] [Accepted: 01/20/2024] [Indexed: 02/08/2024] Open
Abstract
Mapping the cellular refractive index (RI) is a central task for research involving the composition of microorganisms and the development of models providing automated medical screenings with accuracy beyond 95%. These models require significantly enhancing the state-of-the-art RI mapping capabilities to provide large amounts of accurate RI data at high throughput. Here, we present a machine-learning-based technique that obtains a biological specimen's real-time RI and thickness maps from a single image acquired with a conventional color camera. This technology leverages a suitably engineered nanostructured membrane that stretches a biological analyte over its surface and absorbs transmitted light, generating complex reflection spectra from each sample point. The technique does not need pre-existing sample knowledge. It achieves 10-4 RI sensitivity and sub-nanometer thickness resolution on diffraction-limited spatial areas. We illustrate practical application by performing sub-cellular segmentation of HCT-116 colorectal cancer cells, obtaining complete three-dimensional reconstruction of the cellular regions with a characteristic length of 30 μm. These results can facilitate the development of real-time label-free technologies for biomedical studies on microscopic multicellular dynamics.
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Affiliation(s)
- Arturo Burguete-Lopez
- PRIMALIGHT, Computer, Electrical and Mathematical Sciences and Engineering (CEMSE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Maksim Makarenko
- PRIMALIGHT, Computer, Electrical and Mathematical Sciences and Engineering (CEMSE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Marcella Bonifazi
- PRIMALIGHT, Computer, Electrical and Mathematical Sciences and Engineering (CEMSE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
- Physik-Institut, University of Zurich, Winterthurerstrasse 190, Zurich, 8057, Switzerland
| | - Barbara Nicoly Menezes de Oliveira
- PRIMALIGHT, Computer, Electrical and Mathematical Sciences and Engineering (CEMSE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Fedor Getman
- PRIMALIGHT, Computer, Electrical and Mathematical Sciences and Engineering (CEMSE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Yi Tian
- PRIMALIGHT, Computer, Electrical and Mathematical Sciences and Engineering (CEMSE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Valerio Mazzone
- PRIMALIGHT, Computer, Electrical and Mathematical Sciences and Engineering (CEMSE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
- Physik-Institut, University of Zurich, Winterthurerstrasse 190, Zurich, 8057, Switzerland
| | - Ning Li
- PRIMALIGHT, Computer, Electrical and Mathematical Sciences and Engineering (CEMSE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Alessandro Giammona
- Biological and Environmental Science and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
- Institute of Molecular Bioimaging and Physiology (IBFM), National Research Council (CNR), Segrate, Italy
| | - Carlo Liberale
- Biological and Environmental Science and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Andrea Fratalocchi
- PRIMALIGHT, Computer, Electrical and Mathematical Sciences and Engineering (CEMSE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia.
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Zhao J, Liu L, Wang T, Zhang J, Wang X, Du X, Hao R, Liu J, Liu Y, Liu Y. Quantitative phase imaging of living red blood cells combining digital holographic microscopy and deep learning. JOURNAL OF BIOPHOTONICS 2023; 16:e202300090. [PMID: 37321984 DOI: 10.1002/jbio.202300090] [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: 03/17/2023] [Revised: 06/12/2023] [Accepted: 06/13/2023] [Indexed: 06/17/2023]
Abstract
Digital holographic microscopy as a non-contacting, non-invasive, and highly accurate measurement technology, is becoming a valuable method for quantitatively investigating cells and tissues. Reconstruction of phases from a digital hologram is a key step in quantitative phase imaging for biological and biomedical research. This study proposes a two-stage deep convolutional neural network named VY-Net, to realize the effective and robust phase reconstruction of living red blood cells. The VY-Net can obtain the phase information of an object directly from a single-shot off-axis digital hologram. We also propose two new indices to evaluate the reconstructed phases. In experiments, the mean of the structural similarity index of reconstructed phases can reach 0.9309, and the mean of the accuracy of reconstructions of reconstructed phases is as high as 91.54%. An unseen phase map of a living human white blood cell is successfully reconstructed by the trained VY-Net, demonstrating its strong generality.
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Affiliation(s)
- Jiaxi Zhao
- School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu, China
| | - Lin Liu
- School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu, China
| | - Tianhe Wang
- School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu, China
| | - Jing Zhang
- School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu, China
| | - Xiangzhou Wang
- School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu, China
| | - Xiaohui Du
- School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu, China
| | - Ruqian Hao
- School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu, China
| | - Juanxiu Liu
- School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu, China
| | - Yi Liu
- School of Physics, University of Electronic Science and Technology of China, Chengdu, China
| | - Yong Liu
- School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu, China
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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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5
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Bokemeyer A, Buskermolen J, Ketelhut S, Tepasse PR, Vollenberg R, Trebicka J, Schmidt HH, Vieth M, Bettenworth D, Kemper B. Quantitative Phase Imaging Using Digital Holographic Microscopy to Assess the Degree of Intestinal Inflammation in Patients with Ulcerative Colitis. J Clin Med 2023; 12:4067. [PMID: 37373760 DOI: 10.3390/jcm12124067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Revised: 06/10/2023] [Accepted: 06/12/2023] [Indexed: 06/29/2023] Open
Abstract
Ulcerative colitis (UC) is characterized by chronic inflammation of the colorectum. Histological remission has emerged as a potential future treatment goal; however, the histopathological assessment of intestinal inflammation in UC remains challenging with a multitude of available scoring systems and the need for a pathologist with expertise in inflammatory bowel disease (IBD). In previous studies, quantitative phase imaging (QPI) including digital holographic microscopy (DHM) was successfully applied as an objective method for stain-free quantification of the degree of inflammation in tissue sections. Here, we evaluated the application of DHM for the quantitative assessment of histopathological inflammation in patients with UC. In our study, endoscopically obtained colonic and rectal mucosal biopsy samples from 21 patients with UC were analyzed by capturing DHM-based QPI images that were subsequently evaluated using the subepithelial refractive index (RI). The retrieved RI data were correlated with established histological scoring systems including the Nancy index (NI) as well as with endoscopic and clinical findings. As a primary endpoint, we found a significant correlation between the DHM-based retrieved RI and the NI (R2 = 0.251, p < 0.001). Furthermore, RI values correlated with the Mayo endoscopic subscore (MES; R2 = 0.176, p < 0.001). An area under the receiver operating characteristics (ROC) curve of 0.820 confirms the subepithelial RI as a reliable parameter to distinguish biopsies with histologically active UC from biopsies without evidence of active disease as determined by conventional histopathological examination. An RI higher than 1.3488 was found to be the most sensitive and specific cut-off value to identify histologically active UC (sensitivity of 84% and specificity of 72%). In conclusion, our data demonstrate DHM to be a reliable tool for the quantitative assessment of mucosal inflammation in patients with UC.
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Affiliation(s)
- Arne Bokemeyer
- Department of Gastroenterology, Hepatology and Transplant Medicine, University Hospital of Essen, University Duisburg-Essen, 45147 Essen, Germany
| | - Joost Buskermolen
- Department of Medicine B for Gastroenterology, Hepatology, Endocrinology and Clinical Infectiology, University Hospital Muenster, 48149 Muenster, Germany
| | - Steffi Ketelhut
- Biomedical Technology Center, University of Muenster, 48149 Muenster, Germany
| | - Phil-Robin Tepasse
- Department of Medicine B for Gastroenterology, Hepatology, Endocrinology and Clinical Infectiology, University Hospital Muenster, 48149 Muenster, Germany
| | - Richard Vollenberg
- Department of Medicine B for Gastroenterology, Hepatology, Endocrinology and Clinical Infectiology, University Hospital Muenster, 48149 Muenster, Germany
| | - Jonel Trebicka
- Department of Medicine B for Gastroenterology, Hepatology, Endocrinology and Clinical Infectiology, University Hospital Muenster, 48149 Muenster, Germany
| | - Hartmut H Schmidt
- Department of Gastroenterology, Hepatology and Transplant Medicine, University Hospital of Essen, University Duisburg-Essen, 45147 Essen, Germany
| | - Michael Vieth
- Institut für Pathologie, Friedrich-Alexander-University Erlangen-Nürnberg, Klinikum Bayreuth, 95445 Bayreuth, Germany
| | - Dominik Bettenworth
- Department of Medicine B for Gastroenterology, Hepatology, Endocrinology and Clinical Infectiology, University Hospital Muenster, 48149 Muenster, Germany
- CED Schwerpunktpraxis Münster, 48149 Muenster, Germany
| | - Björn Kemper
- Biomedical Technology Center, University of Muenster, 48149 Muenster, Germany
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6
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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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7
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Jin X, Zhang H, Ni B, Liu W, Hou L, Marsh JH, Ye S, Sun X, Li X, Li S, Dong L, Hou JJ, Sun M, Xu B, Xiong J, Liu X. Label-free sensing of virus-like particles below the sub-diffraction limit by wide-field photon state parametric imaging of a gold nanodot array. NANOSCALE ADVANCES 2021; 3:6882-6887. [PMID: 36132363 PMCID: PMC9419464 DOI: 10.1039/d1na00603g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 10/18/2021] [Indexed: 06/15/2023]
Abstract
A parallel four-quadrant sensing method utilizing a specially designed gold nanodot array is created for sensing virus-like particles with a sub-diffraction limit size (∼100 nm) in a wide-field image. Direct label-free sensing of viruses using multiple four-quadrant sensing channels in parallel in a wide-field view enables the possibility of high-throughput onsite screening of viruses.
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Affiliation(s)
- Xiao Jin
- School of Electronic and Optical Engineering, Nanjing University of Science and Technology Nanjing 210094 P. R. China
| | - Heng Zhang
- School of Electronic and Optical Engineering, Nanjing University of Science and Technology Nanjing 210094 P. R. China
| | - Bin Ni
- School of Electronic and Optical Engineering, Nanjing University of Science and Technology Nanjing 210094 P. R. China
| | - Weiping Liu
- School of Electronic and Optical Engineering, Nanjing University of Science and Technology Nanjing 210094 P. R. China
| | - Lianping Hou
- James Watt School of Engineering, University of Glasgow Glasgow G12 8QQ UK
| | - John H Marsh
- James Watt School of Engineering, University of Glasgow Glasgow G12 8QQ UK
| | - Shengwei Ye
- James Watt School of Engineering, University of Glasgow Glasgow G12 8QQ UK
| | - Xiao Sun
- James Watt School of Engineering, University of Glasgow Glasgow G12 8QQ UK
| | - Xiaofeng Li
- State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, The first affiliated Hospital of Guangzhou Medical University Guangzhou 510182 P. R. China
| | - Shanhu Li
- Department of Cell Engineering, Beijing Institute of Biotechnology Beijing 100850 P. R. China
| | - Lei Dong
- School of Life Science, Beijing Institute of Technology Beijing 100081 P. R. China
| | - Jamie Jiangmin Hou
- The Royal College of Surgeons of Edinburgh Nicolson Street Edinburgh Scotland EH8 9DW UK
| | - Ming Sun
- School of Electronic and Optical Engineering, Nanjing University of Science and Technology Nanjing 210094 P. R. China
| | - Bin Xu
- School of Electronic and Optical Engineering, Nanjing University of Science and Technology Nanjing 210094 P. R. China
| | - Jichuan Xiong
- School of Electronic and Optical Engineering, Nanjing University of Science and Technology Nanjing 210094 P. R. China
| | - Xuefeng Liu
- School of Electronic and Optical Engineering, Nanjing University of Science and Technology Nanjing 210094 P. R. China
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Ojaghi A, Casteleiro Costa P, Caruso C, Lam WA, Robles FE. Label-free automated neutropenia detection and grading using deep-ultraviolet microscopy. BIOMEDICAL OPTICS EXPRESS 2021; 12:6115-6128. [PMID: 34745725 PMCID: PMC8547990 DOI: 10.1364/boe.434465] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 08/30/2021] [Accepted: 08/31/2021] [Indexed: 05/20/2023]
Abstract
Neutropenia is a condition identified by an abnormally low number of neutrophils in the bloodstream and signifies an increased risk of severe infection. Cancer patients are particularly susceptible to this condition, which can be disruptive to their treatment and even life-threatening in severe cases. Thus, it is critical to routinely monitor neutrophil counts in cancer patients. However, the standard of care to assess neutropenia, the complete blood count (CBC), requires expensive and complex equipment, as well as cumbersome procedures, which precludes easy or timely access to critical hematological information, namely neutrophil counts. Here we present a simple, low-cost, fast, and robust technique to detect and grade neutropenia based on label-free multi-spectral deep-UV microscopy. Results show that the developed framework for automated segmentation and classification of live, unstained blood cells in a smear accurately differentiates patients with moderate and severe neutropenia from healthy samples in minutes. This work has significant implications towards the development of a low-cost and easy-to-use point-of-care device for tracking neutrophil counts, which can not only improve the quality of life and treatment-outcomes of many patients but can also be lifesaving.
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Affiliation(s)
- Ashkan Ojaghi
- Wallace H. Coulter Department of Biomedical Engineering,
Georgia Institute of Technology and Emory
University, Atlanta, GA 30332, USA
- These authors contributed equally
| | - Paloma Casteleiro Costa
- School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
- These authors contributed equally
| | - Christina Caruso
- Aflac Cancer and Blood Disorders Center of
Children's Healthcare of Atlanta and Department of Pediatrics,
Emory University School of Medicine,
Atlanta, GA 30322, USA
| | - Wilbur A. Lam
- Wallace H. Coulter Department of Biomedical Engineering,
Georgia Institute of Technology and Emory
University, Atlanta, GA 30332, USA
- Aflac Cancer and Blood Disorders Center of
Children's Healthcare of Atlanta and Department of Pediatrics,
Emory University School of Medicine,
Atlanta, GA 30322, USA
| | - Francisco E. Robles
- Wallace H. Coulter Department of Biomedical Engineering,
Georgia Institute of Technology and Emory
University, Atlanta, GA 30332, USA
- School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
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9
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Significant difference in response of malignant tumor cells of individual patients to photodynamic treatment as revealed by digital holographic microscopy. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2021; 221:112235. [PMID: 34126589 DOI: 10.1016/j.jphotobiol.2021.112235] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 04/21/2021] [Accepted: 05/28/2021] [Indexed: 01/17/2023]
Abstract
The investigation of in-vitro response of cell cultures derived from tumor material of individual patients with similar tumor localizations to photodynamic treatment is presented. Tumor types included in the research were renal cell carcinoma, melanoma and alveolar, synovial, lypo- and osteo- sarcomas. Long-term observations of treatment-induced morphological changes in cells were performed by means of digital holographic microscopy. A substantial variance in response of cells of individual patients with similar tumor types and localizations to photodynamic treatment with the same dose has been observed. These peculiarities are indicative of the demand to personalized protocols of photodynamic treatment. The elevated resistance of cells of some patients to treatment at high doses highlights potential limitations of photodynamic therapy for some patients. Digital holographic microscopy is shown to be an informative label-free noninvasive tool allowing for long-term monitoring of cell samples in vitro and providing quantitative information on necrosis rate and loss of cellular dry mass. The developed methodology can be generalized for analysis of cellular response to various therapies.
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10
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Guo R, Barnea I, Shaked NT. Limited-angle tomographic phase microscopy utilizing confocal scanning fluorescence microscopy. BIOMEDICAL OPTICS EXPRESS 2021; 12:1869-1881. [PMID: 33996204 PMCID: PMC8086471 DOI: 10.1364/boe.419598] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 02/12/2021] [Accepted: 02/16/2021] [Indexed: 05/03/2023]
Abstract
We present a multimodal imaging technique, combining tomographic phase microscopy with limited angular projection range and number, and two-channel spinning-disk confocal scanning fluorescence microscopy. This technique allows high-accuracy 3D refractive index (RI) profiling of live cells in spite of the missing projections. The cellular outer shape and its interior organelles measured by the confocal fluorescence imaging not only specify the cell in molecular levels, but also provide the 3D distributions of the whole cell as well as its organelles. We take these additional 3D morphological details as constraints in Gerchberg-Papoulis-based optical diffraction tomography algorithm. We then obtain an accurate 3D RI tomogram, even with a sparse angular range having a small number of perspective projections, otherwise providing low-accuracy RI reconstruction. Then, we obtain both cellular molecular specificity and inner RI values of the cell and its organelles. We compare the reconstructed 3D RI profiles of various samples, demonstrating the superiority of the proposed technique.
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11
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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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12
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Kim D, Lee S, Lee M, Oh J, Yang SA, Park Y. Holotomography: Refractive Index as an Intrinsic Imaging Contrast for 3-D Label-Free Live Cell Imaging. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1310:211-238. [PMID: 33834439 DOI: 10.1007/978-981-33-6064-8_10] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Live cell imaging provides essential information in the investigation of cell biology and related pathophysiology. Refractive index (RI) can serve as intrinsic optical imaging contrast for 3-D label-free and quantitative live cell imaging, and provide invaluable information to understand various dynamics of cells and tissues for the study of numerous fields. Recently significant advances have been made in imaging methods and analysis approaches utilizing RI, which are now being transferred to biological and medical research fields, providing novel approaches to investigate the pathophysiology of cells. To provide insight into how RI can be used as an imaging contrast for imaging of biological specimens, here we provide the basic principle of RI-based imaging techniques and summarize recent progress on applications, ranging from microbiology, hematology, infectious diseases, hematology, and histopathology.
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Affiliation(s)
- Doyeon Kim
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, South Korea
| | - Sangyun Lee
- Department of Physics, KAIST, Daejeon, South Korea
| | - Moosung Lee
- Department of Physics, KAIST, Daejeon, South Korea
| | - Juntaek Oh
- Department of Physics, KAIST, Daejeon, South Korea
| | - Su-A Yang
- Department of Biological Sciences, KAIST, Daejeon, South Korea
| | - YongKeun Park
- Department of Physics, KAIST, Daejeon, South Korea. .,KAIST Institute Health Science and Technology, Daejeon, South Korea. .,Tomocube Inc., Daejeon, South Korea.
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13
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Gul B, Ashraf S, Khan S, Nisar H, Ahmad I. Cell refractive index: Models, insights, applications and future perspectives. Photodiagnosis Photodyn Ther 2020; 33:102096. [PMID: 33188939 DOI: 10.1016/j.pdpdt.2020.102096] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 10/26/2020] [Accepted: 11/02/2020] [Indexed: 01/09/2023]
Abstract
Cell refractive index (RI) is an intrinsic optical parameter that governs the propagation of light (i.e., scattering and absorption) in the cell matrix. The RI of cell is sensitively correlated with its mass distribution and thereby has the capability to provide important insights for diverse biological models. Herein, we review the cell refractive index and the fundamental models for measurement of cell RI, summarize the published RI data of cell and cell organelles and discuss the associated insights. Illustrative applications of cell RI in cell biology are also outlined. Finally, future research trends and applications of cell RI, including novel imaging techniques, reshaping flow cytometry and microfluidic platforms for single cell manipulation are discussed. The rapid technological advances in optical imaging integrated with microfluidic regime seems to enable deeper understanding of subcellular dynamics with high spatio-temporal resolution in real time.
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Affiliation(s)
- Banat Gul
- Department of Basic Sciences, Military College of Engineering, National University of Science and Technology (NUST), Islamabad, Pakistan
| | - Sumara Ashraf
- Department of Physics, The Women University Multan, Pakistan
| | - Shamim Khan
- Department of Physics, Islamia College Peshawar, Khyber Pakhtunkhwa, Pakistan
| | - Hasan Nisar
- Radiation Biology Department, Institute of Aerospace Medicine, German Aerospace Center (DLR), Germany
| | - Iftikhar Ahmad
- Institute of Radiotherapy and Nuclear Medicine (IRNUM), Peshawar, Pakistan.
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14
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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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15
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Li Y, Di J, Wang K, Wang S, Zhao J. Classification of cell morphology with quantitative phase microscopy and machine learning. OPTICS EXPRESS 2020; 28:23916-23927. [PMID: 32752380 DOI: 10.1364/oe.397029] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 07/21/2020] [Indexed: 06/11/2023]
Abstract
We describe and compare two machine learning approaches for cell classification based on label-free quantitative phase imaging with transport of intensity equation methods. In one approach, we design a multilevel integrated machine learning classifier including various individual models such as artificial neural network, extreme learning machine and generalized logistic regression. In another approach, we apply a pretrained convolutional neural network using transfer learning for the classification. As a validation, we show the performances of both approaches on classification between macrophages cultured in normal gravity and microgravity with quantitative phase imaging. The multilevel integrated classifier achieves average accuracy 93.1%, which is comparable to the average accuracy 93.5% obtained by convolutional neural network. The presented quantitative phase imaging system with two classification approaches could be helpful to biomedical scientists for easy and accurate cell analysis.
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16
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Abstract
Hematological analysis, via a complete blood count (CBC) and microscopy, is critical for screening, diagnosing, and monitoring blood conditions and diseases but requires complex equipment, multiple chemical reagents, laborious system calibration and procedures, and highly trained personnel for operation. Here we introduce a hematological assay based on label-free molecular imaging with deep-ultraviolet microscopy that can provide fast quantitative information of key hematological parameters to facilitate and improve hematological analysis. We demonstrate that this label-free approach yields 1) a quantitative five-part white blood cell differential, 2) quantitative red blood cell and hemoglobin characterization, 3) clear identification of platelets, and 4) detailed subcellular morphology. Analysis of tens of thousands of live cells is achieved in minutes without any sample preparation. Finally, we introduce a pseudocolorization scheme that accurately recapitulates the appearance of cells under conventional staining protocols for microscopic analysis of blood smears and bone marrow aspirates. Diagnostic efficacy is evaluated by a panel of hematologists performing a blind analysis of blood smears from healthy donors and thrombocytopenic and sickle cell disease patients. This work has significant implications toward simplifying and improving CBC and blood smear analysis, which is currently performed manually via bright-field microscopy, and toward the development of a low-cost, easy-to-use, and fast hematological analyzer as a point-of-care device and for low-resource settings.
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17
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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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18
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Soto JM, Mas A, Rodrigo JA, Alieva T, Domínguez-Bernal G. Label-free bioanalysis of Leishmania infantum using refractive index tomography with partially coherent illumination. JOURNAL OF BIOPHOTONICS 2019; 12:e201900030. [PMID: 31081235 DOI: 10.1002/jbio.201900030] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 04/09/2019] [Accepted: 05/10/2019] [Indexed: 06/09/2023]
Abstract
In this work, we report the use of refractive index (RI) tomography for quantitative analysis of unstained DH82 cell line infected with Leishmania infantum. The cell RI is reconstructed by using a modality of optical diffraction tomography technique that employs partially coherent illumination, thus enabling inherent compatibility with conventional wide-field microscopes. The experimental results demonstrate that the cell dry mass concentration (DMC) obtained from the RI allows for reliable detection and quantitative characterization of the infection and its temporal evolution. The RI provides important insight for studying morphological changes, particularly membrane blebbing linked to an apoptosis (cell death) process induced by the disease. Moreover, the results evidence that infected DH82 cells exhibit a higher DMC than healthy samples. These findings open up promising perspectives for clinical diagnosis of Leishmania.
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Affiliation(s)
- Juan M Soto
- Department of Optics, Faculty of Physical Sciences, Complutense University of Madrid, Madrid, Spain
| | - Alicia Mas
- Department of Animal Health, Faculty of Veterinary Science, Complutense University of Madrid, Madrid, Spain
| | - José A Rodrigo
- Department of Optics, Faculty of Physical Sciences, Complutense University of Madrid, Madrid, Spain
| | - Tatiana Alieva
- Department of Optics, Faculty of Physical Sciences, Complutense University of Madrid, Madrid, Spain
| | - Gustavo Domínguez-Bernal
- Department of Animal Health, Faculty of Veterinary Science, Complutense University of Madrid, Madrid, Spain
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19
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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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20
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Kapplusch F, Schulze F, Rabe-Matschewsky S, Russ S, Herbig M, Heymann MC, Schoepf K, Stein R, Range U, Rösen-Wolff A, Winkler S, Hedrich CM, Guck J, Hofmann SR. CASP1 variants influence subcellular caspase-1 localization, pyroptosome formation, pro-inflammatory cell death and macrophage deformability. Clin Immunol 2019; 208:108232. [PMID: 31252176 DOI: 10.1016/j.clim.2019.06.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2019] [Revised: 05/27/2019] [Accepted: 06/24/2019] [Indexed: 12/19/2022]
Abstract
CASP1 variants result in reduced enzymatic activity of procaspase-1 and impaired IL-1β release. Despite this, affected individuals can develop systemic autoinflammatory disease. These seemingly contradictory observations have only partially been explained by increased NF-κB activation through prolonged interaction of variant procaspase-1 with RIP2. To identify further disease underlying pathomechanisms, we established an in vitro model using shRNA-directed knock-down of procaspase-1 followed by viral transduction of human monocytes (THP-1) with plasmids encoding for wild-type procaspase-1, disease-associated CASP1 variants (p.L265S, p.R240Q) or a missense mutation in the active center of procaspase-1 (p.C285A). THP1-derived macrophages carrying CASP1 variants exhibited mutation-specific molecular alterations. We here provide in vitro evidence for abnormal pyroptosome formation (p.C285A, p.240Q, p.L265S), impaired nuclear (pro)caspase-1 localization (p.L265S), reduced pro-inflammatory cell death (p.C285A) and changes in macrophage deformability that may contribute to disease pathophysiology of patients with CASP1 variants. This offers previously unknown molecular pathomechanisms in patients with systemic autoinflammatory disease.
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Affiliation(s)
- Franz Kapplusch
- Department of Pediatrics, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany; Department of Women's & Children's Health, Institute of Translational Medicine, University of Liverpool, Liverpool, UK
| | - Felix Schulze
- Department of Pediatrics, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Sabrina Rabe-Matschewsky
- Department of Pediatrics, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Susanne Russ
- Department of Pediatrics, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Maik Herbig
- Biotechnology Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Dresden, Germany
| | - Michael Christian Heymann
- Department of Pediatrics, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Katharina Schoepf
- Department of Pediatrics, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Robert Stein
- Department of Pediatrics, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Ursula Range
- Institute for Medical Informatics and Biometry, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Angela Rösen-Wolff
- Department of Pediatrics, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Stefan Winkler
- Department of Pediatrics, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Christian Michael Hedrich
- Department of Pediatrics, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany; Department of Women's & Children's Health, Institute of Translational Medicine, University of Liverpool, Liverpool, UK; Department of Paediatric Rheumatology, Alder Hey Children's NHS Foundation Trust Hospital, Liverpool, UK
| | - Jochen Guck
- Biotechnology Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Dresden, Germany
| | - Sigrun Ruth Hofmann
- Department of Pediatrics, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.
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21
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Hassani H, Kreysing E. Noninvasive measurement of the refractive index of cell organelles using surface plasmon resonance microscopy. OPTICS LETTERS 2019; 44:1359-1362. [PMID: 30874650 DOI: 10.1364/ol.44.001359] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Accepted: 02/09/2019] [Indexed: 06/09/2023]
Abstract
The health of a eukaryotic cell depends on the proper functioning of its cell organelles. Characterizing these nanometer- to micrometer-scaled specialized subunits without disturbing the cell is challenging but can also provide valuable insights regarding the state of a cell. We show that objective-based scanning surface plasmon resonance microscopy can be used to analyze the refractive index of cell organelles quantitatively in a noninvasive and label-free manner with a lateral resolution at the diffraction limit.
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22
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King D, Glynn M, Cindric S, Kernan D, O'Connell T, Hakimjavadi R, Kearney S, Ackermann T, Berbel XM, Llobera A, Simonsen U, Laursen BE, Redmond EM, Cahill PA, Ducrée J. Label-Free Multi Parameter Optical Interrogation of Endothelial Activation in Single Cells using a Lab on a Disc Platform. Sci Rep 2019; 9:4157. [PMID: 30858536 PMCID: PMC6411894 DOI: 10.1038/s41598-019-40612-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Accepted: 01/31/2019] [Indexed: 12/31/2022] Open
Abstract
Cellular activation and inflammation leading to endothelial dysfunction is associated with cardiovascular disease (CVD). We investigated whether a single cell label-free multi parameter optical interrogation system can detect endothelial cell and endothelial progenitor cell (EPC) activation in vitro and ex vivo, respectively. Cultured human endothelial cells were exposed to increasing concentrations of tumour necrosis factor alpha (TNF-α) or lipopolysaccharide (LPS) before endothelial activation was validated using fluorescence-activated cell sorting (FACS) analysis of inflammatory marker expression (PECAM-1, E-selectin and ICAM-1). A centrifugal microfluidic system and V-cup array was used to capture individual cells before optical measurement of light scattering, immunocytofluorescence, auto-fluorescence (AF) and cell morphology was determined. In vitro, TNF-α promoted specific changes to the refractive index and cell morphology of individual cells concomitant with enhanced photon activity of fluorescently labelled inflammatory markers and increased auto-fluorescence (AF) intensity at three different wavelengths, an effect blocked by inhibition of downstream signalling with Iκβ. Ex vivo, there was a significant increase in EPC number and AF intensity of individual EPCs from CVD patients concomitant with enhanced PECAM-1 expression when compared to normal controls. This novel label-free 'lab on a disc' (LoaD) platform can successfully detect endothelial activation in response to inflammatory stimuli in vitro and ex vivo.
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Affiliation(s)
- Damien King
- Dublin City University, School of Physical Sciences, National Centre for Sensor Research, Dublin, Ireland
| | - MacDara Glynn
- Dublin City University, School of Physical Sciences, National Centre for Sensor Research, Dublin, Ireland
| | - Sandra Cindric
- Dublin City University, School of Physical Sciences, National Centre for Sensor Research, Dublin, Ireland
| | - David Kernan
- Dublin City University, School of Physical Sciences, National Centre for Sensor Research, Dublin, Ireland
| | - Tríona O'Connell
- Dublin City University, School of Biotechnology, Irish Science Separation Cluster, Dublin, Ireland
| | - Roya Hakimjavadi
- Dublin City University, School of Biotechnology, Vascular Biology & Therapeutics, Dublin, Ireland
| | - Sinéad Kearney
- Dublin City University, School of Physical Sciences, National Centre for Sensor Research, Dublin, Ireland
| | - Tobias Ackermann
- Dublin City University, School of Biotechnology, Vascular Biology & Therapeutics, Dublin, Ireland
| | | | - Andreu Llobera
- Centre Nacional de Microelectronica, Campus UAB, Barcelona, Spain
| | - Ulf Simonsen
- Aarhus University, Department of Biomedicine, Aarhus, Denmark
| | - Britt E Laursen
- Aarhus University, Department of Biomedicine, Aarhus, Denmark
| | - Eileen M Redmond
- University of Rochester, Dept Surgery Rochester, New York, United States
| | - Paul A Cahill
- Dublin City University, School of Biotechnology, Vascular Biology & Therapeutics, Dublin, Ireland
| | - Jens Ducrée
- Dublin City University, School of Physical Sciences, National Centre for Sensor Research, Dublin, Ireland.
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23
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Midtvedt D, Olsén E, Höök F, Jeffries GDM. Label-free spatio-temporal monitoring of cytosolic mass, osmolarity, and volume in living cells. Nat Commun 2019; 10:340. [PMID: 30664642 PMCID: PMC6341078 DOI: 10.1038/s41467-018-08207-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2018] [Accepted: 12/13/2018] [Indexed: 02/08/2023] Open
Abstract
Microorganisms adapt their biophysical properties in response to changes in their local environment. However, quantifying these changes at the single-cell level has only recently become possible, largely relying on fluorescent labeling strategies. In this work, we utilize yeast (Saccharomyces cerevisiae) to demonstrate label-free quantification of changes in both intracellular osmolarity and macromolecular concentration in response to changes in the local environment. By combining a digital holographic microscope with a millifluidic chip, the temporal response of cellular water flux was successfully isolated from the rate of production of higher molecular weight compounds, in addition to identifying the produced compounds in terms of the product of their refractive index increment [Formula: see text] and molar mass. The ability to identify, quantify and temporally resolve multiple biophysical processes in living cells at the single cell level offers a crucial complement to label-based strategies, suggesting broad applicability in studies of a wide-range of cellular processes.
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Affiliation(s)
- Daniel Midtvedt
- Department of Physics, Chalmers University of Technology, Gothenburg, Sweden.
| | - Erik Olsén
- Department of Physics, Chalmers University of Technology, Gothenburg, Sweden
| | - Fredrik Höök
- Department of Physics, Chalmers University of Technology, Gothenburg, Sweden
| | - Gavin D M Jeffries
- Department of Chemistry, Chalmers University of Technology, Gothenburg, Sweden
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24
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Label-free non-invasive quantitative measurement of lipid contents in individual microalgal cells using refractive index tomography. Sci Rep 2018; 8:6524. [PMID: 29695726 PMCID: PMC5916925 DOI: 10.1038/s41598-018-24393-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Accepted: 03/26/2018] [Indexed: 01/12/2023] Open
Abstract
Microalgae are promising candidates for biofuel production due to their high lipid content. To facilitate utilization of the microalgae for biofuel, rapid quantification of the lipid contents in microalgae is necessary. However, conventional methods based on the chemical extraction of lipids require a time-consuming destructive extraction process. Here, we demonstrate label-free, non-invasive, rapid quantification of the lipid contents in individual micro-algal cells measuring the three-dimensional refractive index tomograms. We measure three-dimensional refractive index distributions within Nannochloropsis oculata cells and find that lipid droplets are identifiable in tomograms by their high refractive index. In addition, we alter N. oculata under nitrogen deficiency by measuring the volume, lipid weight, and dry cell weight of individual cells. Characterization of individual cells allows correlative analysis between the lipid content and size of individual cells.
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25
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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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26
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Noninvasive detection of macrophage activation with single-cell resolution through machine learning. Proc Natl Acad Sci U S A 2018; 115:E2676-E2685. [PMID: 29511099 DOI: 10.1073/pnas.1711872115] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
We present a method enabling the noninvasive study of minute cellular changes in response to stimuli, based on the acquisition of multiple parameters through label-free microscopy. The retrieved parameters are related to different attributes of the cell. Morphological variables are extracted from quantitative phase microscopy and autofluorescence images, while molecular indicators are retrieved via Raman spectroscopy. We show that these independent parameters can be used to build a multivariate statistical model based on logistic regression, which we apply to the detection at the single-cell level of macrophage activation induced by lipopolysaccharide (LPS) exposure and compare their respective performance in assessing the individual cellular state. The models generated from either morphology or Raman can reliably and independently detect the activation state of macrophage cells, which is validated by comparison with their cytokine secretion and intracellular expression of molecules related to the immune response. The independent models agree on the degree of activation, showing that the features provide insight into the cellular response heterogeneity. We found that morphological indicators are linked to the phenotype, which is mostly related to downstream effects, making the results obtained with these variables dose-dependent. On the other hand, Raman indicators are representative of upstream intracellular molecular changes related to specific activation pathways. By partially inhibiting the LPS-induced activation using progesterone, we could identify several subpopulations, showing the ability of our approach to identify the effect of LPS activation, specific inhibition of LPS, and also the effect of progesterone alone on macrophage cells.
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27
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Dardikman G, Nygate YN, Barnea I, Turko NA, Singh G, Javidi B, Shaked NT. Integral refractive index imaging of flowing cell nuclei using quantitative phase microscopy combined with fluorescence microscopy. BIOMEDICAL OPTICS EXPRESS 2018. [PMID: 29541511 PMCID: PMC5846521 DOI: 10.1364/boe.9.001177] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
We suggest a new multimodal imaging technique for quantitatively measuring the integral (thickness-average) refractive index of the nuclei of live biological cells in suspension. For this aim, we combined quantitative phase microscopy with simultaneous 2-D fluorescence microscopy. We used 2-D fluorescence microscopy to localize the nucleus inside the quantitative phase map of the cell, as well as for measuring the nucleus radii. As verified offline by both 3-D confocal fluorescence microscopy and 2-D fluorescence microscopy while rotating the cells during flow, the nucleus of cells in suspension that are not during division can be assumed to be an ellipsoid. The entire shape of a cell in suspension can be assumed to be a sphere. Then, the cell and nucleus 3-D shapes can be evaluated based on their in-plain radii available from the 2-D phase and fluorescent measurements, respectively. Finally, the nucleus integral refractive index profile is calculated. We demonstrate the new technique on cancer cells, obtaining nucleus refractive index values that are lower than those of the cytoplasm, coinciding with recent findings. We believe that the proposed technique has the potential to be used for flow cytometry, where full 3-D refractive index tomography is too slow to be implemented during flow.
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Affiliation(s)
- Gili Dardikman
- Tel Aviv University, Faculty of Engineering, Department of Biomedical Engineering, Tel Aviv 69978, Israel
| | - Yoav N. Nygate
- Tel Aviv University, Faculty of Engineering, Department of Biomedical Engineering, Tel Aviv 69978, Israel
| | - Itay Barnea
- Tel Aviv University, Faculty of Engineering, Department of Biomedical Engineering, Tel Aviv 69978, Israel
| | - Nir A. Turko
- Tel Aviv University, Faculty of Engineering, Department of Biomedical Engineering, Tel Aviv 69978, Israel
| | - Gyanendra Singh
- Tel Aviv University, Faculty of Engineering, Department of Biomedical Engineering, Tel Aviv 69978, Israel
| | - Barham Javidi
- University of Connecticut, Faculty of Engineering, Department of Electrical and Computer Engineering, Storrs 06269-4157, Connecticut, USA
| | - Natan T. Shaked
- Tel Aviv University, Faculty of Engineering, Department of Biomedical Engineering, Tel Aviv 69978, Israel
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Ekpenyong AE, Toepfner N, Fiddler C, Herbig M, Li W, Cojoc G, Summers C, Guck J, Chilvers ER. Mechanical deformation induces depolarization of neutrophils. SCIENCE ADVANCES 2017; 3:e1602536. [PMID: 28630905 PMCID: PMC5470826 DOI: 10.1126/sciadv.1602536] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The transition of neutrophils from a resting state to a primed state is an essential requirement for their function as competent immune cells. This transition can be caused not only by chemical signals but also by mechanical perturbation. After cessation of either, these cells gradually revert to a quiescent state over 40 to 120 min. We use two biophysical tools, an optical stretcher and a novel microcirculation mimetic, to effect physiologically relevant mechanical deformations of single nonadherent human neutrophils. We establish quantitative morphological analysis and mechanical phenotyping as label-free markers of neutrophil priming. We show that continued mechanical deformation of primed cells can cause active depolarization, which occurs two orders of magnitude faster than by spontaneous depriming. This work provides a cellular-level mechanism that potentially explains recent clinical studies demonstrating the potential importance, and physiological role, of neutrophil depriming in vivo and the pathophysiological implications when this deactivation is impaired, especially in disorders such as acute lung injury.
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Affiliation(s)
- Andrew E. Ekpenyong
- Cavendish Laboratory, Department of Physics, University of Cambridge, Cambridge CB3 0HE, UK
- Biotechnology Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, 01307 Dresden, Germany
- Department of Physics, Creighton University, Omaha, NE 68178, USA
| | - Nicole Toepfner
- Klinik und Poliklinik für Kinder-und Jugendmedizin, Universitätsklinikum Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
- Department of Medicine, Addenbrooke’s and Papworth Hospitals, University of Cambridge School of Clinical Medicine, Cambridge CB2 0QQ, UK
| | - Christine Fiddler
- Department of Medicine, Addenbrooke’s and Papworth Hospitals, University of Cambridge School of Clinical Medicine, Cambridge CB2 0QQ, UK
| | - Maik Herbig
- Biotechnology Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, 01307 Dresden, Germany
| | - Wenhong Li
- Biotechnology Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, 01307 Dresden, Germany
| | - Gheorghe Cojoc
- Biotechnology Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, 01307 Dresden, Germany
| | - Charlotte Summers
- Department of Medicine, Addenbrooke’s and Papworth Hospitals, University of Cambridge School of Clinical Medicine, Cambridge CB2 0QQ, UK
| | - Jochen Guck
- Cavendish Laboratory, Department of Physics, University of Cambridge, Cambridge CB3 0HE, UK
- Biotechnology Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, 01307 Dresden, Germany
- Corresponding author.
| | - Edwin R. Chilvers
- Department of Medicine, Addenbrooke’s and Papworth Hospitals, University of Cambridge School of Clinical Medicine, Cambridge CB2 0QQ, UK
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Wang W, Li Z, Meng Q, Zhang P, Yan P, Zhang Z, Zhang H, Pan J, Zhai Y, Liu Y, Wang X, Li W, Zhao Y. Chronic Calcium Channel Inhibitor Verapamil Antagonizes TNF-α-Mediated Inflammatory Reaction and Protects Against Inflammatory Arthritis in Mice. Inflammation 2017; 39:1624-34. [PMID: 27438468 DOI: 10.1007/s10753-016-0396-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
It is well established that the tumor necrosis factor-α (TNF-α) plays a dominant role in rheumatoid arthritis (RA). Calcium channel is recently reported to be closely associated with various inflammatory diseases. However, whether chronic calcium channel blocker verapamil plays a role in RA still remains unknown. To investigate the role of verapamil in antagonizing TNF-α-mediated inflammation reaction and the underlying mechanisms, bone marrow-derived macrophages (BMDM) cells were cultured with stimulation of TNF-α, in the presence or absence of verapamil. Inflammation-associated cytokines, including IL-1, IL-6, inducible nitric oxide synthase 2 (NOS-2), and cyclooxygenase-2 (COX-2), were assessed, and verapamil suppressed TNF-α-induced expression of inflammatory cytokines. Furthermore, collagen-induced arthritis (CIA) mice models were established, and arthritis progression was evaluated by clinical and histological signs of arthritis. Treatment of verapamil attenuated inflammation as well as joint destruction in arthritis models. In addition, activity of NF-kB signaling pathway was determined both in vitro and in mice arthritis models, and verapamil inhibited TNF-α-induced activation of NF-kB signaling both in vitro and in mice models. Collectively, chronic calcium channel blocker verapamil may shed light on treatment of inflammatory arthritis and provide a potential therapeutic instrument for RA in the future.
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Affiliation(s)
- Wenhan Wang
- School of Medicine, Shandong University, Jinan, Shandong, 250012, People's Republic of China
| | - Zhong Li
- Department of Orthopaedics, Liaocheng Clinical Academy, Taishan Medical University, Liaocheng, Shandong, 252000, People's Republic of China
| | - Qingjuan Meng
- The Third People's Hospital of Jinan, Jinan, Shandong, 250101, People's Republic of China
| | - Pei Zhang
- School of Medicine, Shandong University, Jinan, Shandong, 250012, People's Republic of China
| | - Pengcheng Yan
- School of Medicine, Shandong University, Jinan, Shandong, 250012, People's Republic of China
| | - Zhenbiao Zhang
- School of Medicine, Shandong University, Jinan, Shandong, 250012, People's Republic of China
| | - Hao Zhang
- School of Medicine, Shandong University, Jinan, Shandong, 250012, People's Republic of China
| | - Jingrui Pan
- School of Medicine, Shandong University, Jinan, Shandong, 250012, People's Republic of China
| | - Yujia Zhai
- School of Medicine, Shandong University, Jinan, Shandong, 250012, People's Republic of China
| | - Yaoge Liu
- School of Medicine, Shandong University, Jinan, Shandong, 250012, People's Republic of China
| | - Xiaokai Wang
- School of Medicine, Shandong University, Jinan, Shandong, 250012, People's Republic of China
| | - Weiwei Li
- Department of Pathology, Qilu Hospital, Shandong University, Jinan, Shandong, 250012, People's Republic of China.
| | - Yunpeng Zhao
- Department of Orthopaedics, Qilu Hospital, Shandong University, 107 Wenhuaxi Road, Jinan, Shandong, 250012, People's Republic of China.
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30
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Kastl L, Isbach M, Dirksen D, Schnekenburger J, Kemper B. Quantitative phase imaging for cell culture quality control. Cytometry A 2017; 91:470-481. [PMID: 28264140 DOI: 10.1002/cyto.a.23082] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Revised: 02/15/2017] [Accepted: 02/20/2017] [Indexed: 12/16/2022]
Abstract
The potential of quantitative phase imaging (QPI) with digital holographic microscopy (DHM) for quantification of cell culture quality was explored. Label-free QPI of detached single cells in suspension was performed by Michelson interferometer-based self-interference DHM. Two pancreatic tumor cell lines were chosen as cellular model and analyzed for refractive index, volume, and dry mass under varying culture conditions. Firstly, adequate cell numbers for reliable statistics were identified. Then, to characterize the performance and reproducibility of the method, we compared results from independently repeated measurements and quantified the cellular response to osmolality changes of the cell culture medium. Finally, it was demonstrated that the evaluation of QPI images allows the extraction of absolute cell parameters which are related to cell layer confluence states. In summary, the results show that QPI enables label-free imaging cytometry, which provides novel complementary integral biophysical data sets for sophisticated quantification of cell culture quality with minimized sample preparation. © 2017 International Society for Advancement of Cytometry.
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Affiliation(s)
- Lena Kastl
- Biomedical Technology Center, University of Muenster, Mendelstr. 17, Muenster, D-48149, Germany
| | - Michael Isbach
- Biomedical Technology Center, University of Muenster, Mendelstr. 17, Muenster, D-48149, Germany
| | - Dieter Dirksen
- Department of Prosthetic Dentistry and Biomaterials, University of Muenster, Waldeyerstraße 30, Muenster, D-48149, Germany
| | - Jürgen Schnekenburger
- Biomedical Technology Center, University of Muenster, Mendelstr. 17, Muenster, D-48149, Germany
| | - Björn Kemper
- Biomedical Technology Center, University of Muenster, Mendelstr. 17, Muenster, D-48149, Germany
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31
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Singh DK, Ahrens CC, Li W, Vanapalli SA. Label-free fingerprinting of tumor cells in bulk flow using inline digital holographic microscopy. BIOMEDICAL OPTICS EXPRESS 2017; 8:536-554. [PMID: 28270966 PMCID: PMC5330580 DOI: 10.1364/boe.8.000536] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Revised: 12/21/2016] [Accepted: 12/22/2016] [Indexed: 05/19/2023]
Abstract
Large-scale and label-free phenotyping of cells holds great promise in medicine, especially in cancer diagnostics and prognosis. Here, we introduce inline digital holography microscopy for volumetric imaging of cells in bulk flow and fingerprinting of flowing tumor cells based on two metrics, in-focus scattered intensity and cell diameter. Using planar distribution of immobilized particles, we identify the optimal recording distance and microscope objective magnification that minimizes the error in measurement of particle position, size and scattered intensity. Using the optimized conditions and the two metrics, we demonstrate the capacity to enumerate and fingerprint more than 100,000 cells. Finally, we highlight the power of our label-free and high throughput technology by characterizing breast tumor cell lines with different metastatic potentials and distinguishing drug resistant ovarian cancer cells from their parental cell line.
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Affiliation(s)
| | - Caroline C. Ahrens
- Department of Chemical Engineering, Texas Tech University, Lubbock, Texas, USA
| | - Wei Li
- Department of Chemical Engineering, Texas Tech University, Lubbock, Texas, USA
| | - Siva A. Vanapalli
- Department of Chemical Engineering, Texas Tech University, Lubbock, Texas, USA
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32
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Majeed H, Sridharan S, Mir M, Ma L, Min E, Jung W, Popescu G. Quantitative phase imaging for medical diagnosis. JOURNAL OF BIOPHOTONICS 2017; 10:177-205. [PMID: 27539534 DOI: 10.1002/jbio.201600113] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2016] [Revised: 07/06/2016] [Accepted: 07/13/2016] [Indexed: 05/19/2023]
Abstract
Optical microscopy is an indispensable diagnostic tool in modern healthcare. As a prime example, pathologists rely exclusively on light microscopy to investigate tissue morphology in order to make a diagnosis. While advances in light microscopy and contrast markers allow pathologists to visualize cells and tissues in unprecedented detail, the interpretation of these images remains largely subjective, leading to inter- and intra-observer discrepancy. Furthermore, conventional microscopy images capture qualitative information which makes it difficult to automate the process, reducing the throughput achievable in the diagnostic workflow. Quantitative Phase Imaging (QPI) techniques have been advanced in recent years to address these two challenges. By quantifying physical parameters of cells and tissues, these systems remove subjectivity from the disease diagnosis process and allow for easier automation to increase throughput. In addition to providing quantitative information, QPI systems are also label-free and can be easily assimilated into the current diagnostic workflow in the clinic. In this paper we review the advances made in disease diagnosis by QPI techniques. We focus on the areas of hematological diagnosis and cancer pathology, which are the areas where most significant advances have been made to date. [Image adapted from Y. Park, M. Diez-Silva, G. Popescu, G. Lykotrafitis, W. Choi, M. S. Feld, and S. Suresh, Proc. Natl. Acad. Sci. 105, 13730-13735 (2008).].
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Affiliation(s)
- Hassaan Majeed
- Quantitative Light Imaging Lab, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana Champaign, 405 N. Mathews Ave., Urbana, IL, 61801, USA
| | - Shamira Sridharan
- Biomedical Engineering Department, University of California Davis, Genome and Biomedical Sciences Facility #2603B, 451 Health Science Dr., Davis, CA, 95616, USA
| | - Mustafa Mir
- Molecular and Cell Biology, University of California, Berkeley, 485 Li Ka Shing Center, 94720, Berkeley, CA, USA
| | - Lihong Ma
- Institute of Information Optics, Zhejiang Normal University, Jinhua, 321004, China
| | - Eunjung Min
- Department of Biomedical Engineering, Ulsan National Institute of Science and Technology, 50 UNIST-gil, Ulsan, 44919, Republic of Korea
| | - Woonggyu Jung
- Department of Biomedical Engineering, Ulsan National Institute of Science and Technology, 50 UNIST-gil, Ulsan, 44919, Republic of Korea
- Center for Soft and Living Matter, Institute for Basic Science (IBS), 50 UNIST-gil, Ulsan, 44919, Republic of Korea
| | - Gabriel Popescu
- Quantitative Light Imaging Lab, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana Champaign, 405 N. Mathews Ave., Urbana, IL, 61801, USA
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33
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Schürmann M, Scholze J, Müller P, Guck J, Chan CJ. Cell nuclei have lower refractive index and mass density than cytoplasm. JOURNAL OF BIOPHOTONICS 2016; 9:1068-1076. [PMID: 27010098 DOI: 10.1002/jbio.201500273] [Citation(s) in RCA: 104] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Revised: 02/25/2016] [Accepted: 03/01/2016] [Indexed: 05/11/2023]
Abstract
Common perception regards the nucleus as a densely packed object with higher refractive index (RI) and mass density than the surrounding cytoplasm. Here, the volume of isolated nuclei is systematically varied by electrostatic and osmotic conditions as well as drug treatments that modify chromatin conformation. The refractive index and dry mass of isolated nuclei is derived from quantitative phase measurements using digital holographic microscopy (DHM). Surprisingly, the cell nucleus is found to have a lower RI and mass density than the cytoplasm in four different cell lines and throughout the cell cycle. This result has important implications for conceptualizing light tissue interactions as well as biological processes in cells.
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Affiliation(s)
| | - Jana Scholze
- Biotechnology Center, TU Dresden, 01307, Dresden, Germany
| | - Paul Müller
- Biotechnology Center, TU Dresden, 01307, Dresden, Germany
| | - Jochen Guck
- Biotechnology Center, TU Dresden, 01307, Dresden, Germany.
- Cavendish Laboratory, University of Cambridge, Cambridge, CB3 OHE, UK.
| | - Chii J Chan
- Biotechnology Center, TU Dresden, 01307, Dresden, Germany
- Cavendish Laboratory, University of Cambridge, Cambridge, CB3 OHE, UK
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34
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Liu PY, Chin LK, Ser W, Chen HF, Hsieh CM, Lee CH, Sung KB, Ayi TC, Yap PH, Liedberg B, Wang K, Bourouina T, Leprince-Wang Y. Cell refractive index for cell biology and disease diagnosis: past, present and future. LAB ON A CHIP 2016; 16:634-44. [PMID: 26732872 DOI: 10.1039/c5lc01445j] [Citation(s) in RCA: 218] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Cell refractive index is a key biophysical parameter, which has been extensively studied. It is correlated with other cell biophysical properties including mechanical, electrical and optical properties, and not only represents the intracellular mass and concentration of a cell, but also provides important insight for various biological models. Measurement techniques developed earlier only measure the effective refractive index of a cell or a cell suspension, providing only limited information on cell refractive index and hence hindering its in-depth analysis and correlation. Recently, the emergence of microfluidic, photonic and imaging technologies has enabled the manipulation of a single cell and the 3D refractive index of a single cell down to sub-micron resolution, providing powerful tools to study cells based on refractive index. In this review, we provide an overview of cell refractive index models and measurement techniques including microfluidic chip-based techniques for the last 50 years, present the applications and significance of cell refractive index in cell biology, hematology, and pathology, and discuss future research trends in the field, including 3D imaging methods, integration with microfluidics and potential applications in new and breakthrough research areas.
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Affiliation(s)
- P Y Liu
- Université Paris-Est, UPEM, F-77454 Marne-la-Vallée, France.
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35
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Yoon J, Kim K, Park H, Choi C, Jang S, Park Y. Label-free characterization of white blood cells by measuring 3D refractive index maps. BIOMEDICAL OPTICS EXPRESS 2015; 6:3865-75. [PMID: 26504637 PMCID: PMC4605046 DOI: 10.1364/boe.6.003865] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Revised: 08/07/2015] [Accepted: 09/01/2015] [Indexed: 05/02/2023]
Abstract
The characterization of white blood cells (WBCs) is crucial for blood analyses and disease diagnoses. However, current standard techniques rely on cell labeling, a process which imposes significant limitations. Here we present three-dimensional (3D) optical measurements and the label-free characterization of mouse WBCs using optical diffraction tomography. 3D refractive index (RI) tomograms of individual WBCs are constructed from multiple two-dimensional quantitative phase images of samples illuminated at various angles of incidence. Measurements of the 3D RI tomogram of WBCs enable the separation of heterogeneous populations of WBCs using quantitative morphological and biochemical information. Time-lapse tomographic measurements also provide the 3D trajectory of micrometer-sized beads ingested by WBCs. These results demonstrate that optical diffraction tomography can be a useful and versatile tool for the study of WBCs.
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Affiliation(s)
- Jonghee Yoon
- Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 305-701, South Korea
| | - Kyoohyun Kim
- Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 305-701, South Korea
| | - HyunJoo Park
- Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 305-701, South Korea
| | - Chulhee Choi
- Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology, Daejeon 305-701, South Korea
| | - Seongsoo Jang
- Department of Laboratory Medicine, University of Ulsan, College of Medicine and Asan Medical Center, Seoul 138-736, South Korea
| | - YongKeun Park
- Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 305-701, South Korea
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36
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Schubert M, Steude A, Liehm P, Kronenberg NM, Karl M, Campbell EC, Powis SJ, Gather MC. Lasing within Live Cells Containing Intracellular Optical Microresonators for Barcode-Type Cell Tagging and Tracking. NANO LETTERS 2015; 15:5647-52. [PMID: 26186167 DOI: 10.1021/acs.nanolett.5b02491] [Citation(s) in RCA: 88] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
We report on a laser that is fully embedded within a single live cell. By harnessing natural endocytosis of the cell, we introduce a fluorescent whispering gallery mode (WGM) microresonator into the cell cytoplasm. On pumping with nanojoule light pulses, green laser emission is generated inside the cells. Our approach can be applied to different cell types, and cells with microresonators remain viable for weeks under standard conditions. The characteristics of the lasing spectrum provide each cell with a barcode-type label which enables uniquely identifying and tracking individual migrating cells. Self-sustained lasing from cells paves the way to new forms of cell tracking, intracellular sensing, and adaptive imaging.
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Affiliation(s)
- Marcel Schubert
- †SUPA, School of Physics and Astronomy and ‡School of Medicine, University of St Andrews, St Andrews, Fife, Scotland, United Kingdom
| | - Anja Steude
- †SUPA, School of Physics and Astronomy and ‡School of Medicine, University of St Andrews, St Andrews, Fife, Scotland, United Kingdom
| | - Philipp Liehm
- †SUPA, School of Physics and Astronomy and ‡School of Medicine, University of St Andrews, St Andrews, Fife, Scotland, United Kingdom
| | - Nils M Kronenberg
- †SUPA, School of Physics and Astronomy and ‡School of Medicine, University of St Andrews, St Andrews, Fife, Scotland, United Kingdom
| | - Markus Karl
- †SUPA, School of Physics and Astronomy and ‡School of Medicine, University of St Andrews, St Andrews, Fife, Scotland, United Kingdom
| | - Elaine C Campbell
- †SUPA, School of Physics and Astronomy and ‡School of Medicine, University of St Andrews, St Andrews, Fife, Scotland, United Kingdom
| | - Simon J Powis
- †SUPA, School of Physics and Astronomy and ‡School of Medicine, University of St Andrews, St Andrews, Fife, Scotland, United Kingdom
| | - Malte C Gather
- †SUPA, School of Physics and Astronomy and ‡School of Medicine, University of St Andrews, St Andrews, Fife, Scotland, United Kingdom
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37
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Schürmann M, Scholze J, Müller P, Chan CJ, Ekpenyong AE, Chalut KJ, Guck J. Refractive index measurements of single, spherical cells using digital holographic microscopy. Methods Cell Biol 2015; 125:143-59. [PMID: 25640428 DOI: 10.1016/bs.mcb.2014.10.016] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
In this chapter, we introduce digital holographic microscopy (DHM) as a marker-free method to determine the refractive index of single, spherical cells in suspension. The refractive index is a conclusive measure in a biological context. Cell conditions, such as differentiation or infection, are known to yield significant changes in the refractive index. Furthermore, the refractive index of biological tissue determines the way it interacts with light. Besides the biological relevance of this interaction in the retina, a lot of methods used in biology, including microscopy, rely on light-tissue or light-cell interactions. Hence, determining the refractive index of cells using DHM is valuable in many biological applications. This chapter covers the main topics that are important for the implementation of DHM: setup, sample preparation, and analysis. First, the optical setup is described in detail including notes and suggestions for the implementation. Following that, a protocol for the sample and measurement preparation is explained. In the analysis section, an algorithm for the determination of quantitative phase maps is described. Subsequently, all intermediate steps for the calculation of the refractive index of suspended cells are presented, exploiting their spherical shape. In the last section, a discussion of possible extensions to the setup, further measurement configurations, and additional analysis methods are given. Throughout this chapter, we describe a simple, robust, and thus easily reproducible implementation of DHM. The different possibilities for extensions show the diverse fields of application for this technique.
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Affiliation(s)
- Mirjam Schürmann
- Biotechnology Center, Technische Universität Dresden, Tatzberg, Dresden, Germany
| | - Jana Scholze
- Biotechnology Center, Technische Universität Dresden, Tatzberg, Dresden, Germany
| | - Paul Müller
- Biotechnology Center, Technische Universität Dresden, Tatzberg, Dresden, Germany
| | - Chii J Chan
- Cavendish Laboratory, Department of Physics, University of Cambridge, Cambridge, UK; Biotechnology Center, Technische Universität Dresden, Tatzberg, Dresden, Germany
| | - Andrew E Ekpenyong
- Biotechnology Center, Technische Universität Dresden, Tatzberg, Dresden, Germany; Department of Physics, Creighton University, Omaha, NE, USA
| | - Kevin J Chalut
- Cavendish Laboratory, Department of Physics, University of Cambridge, Cambridge, UK; Wellcome Trust/Medical Research Council Stem Cell Institute, Cambridge, UK
| | - Jochen Guck
- Biotechnology Center, Technische Universität Dresden, Tatzberg, Dresden, Germany; Cavendish Laboratory, Department of Physics, University of Cambridge, Cambridge, UK
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38
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Bettenworth D, Lenz P, Krausewitz P, Brückner M, Ketelhut S, Domagk D, Kemper B. Quantitative stain-free and continuous multimodal monitoring of wound healing in vitro with digital holographic microscopy. PLoS One 2014; 9:e107317. [PMID: 25251440 PMCID: PMC4174518 DOI: 10.1371/journal.pone.0107317] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Accepted: 08/08/2014] [Indexed: 12/12/2022] Open
Abstract
Impaired epithelial wound healing has significant pathophysiological implications in several conditions including gastrointestinal ulcers, anastomotic leakage and venous or diabetic skin ulcers. Promising drug candidates for accelerating wound closure are commonly evaluated in in vitro wound assays. However, staining procedures and discontinuous monitoring are major drawbacks hampering accurate assessment of wound assays. We therefore investigated digital holographic microscopy (DHM) to appropriately monitor wound healing in vitro and secondly, to provide multimodal quantitative information on morphological and functional cell alterations as well as on motility changes upon cytokine stimulation. Wound closure as reflected by proliferation and migration of Caco-2 cells in wound healing assays was studied and assessed in time-lapse series for 40 h in the presence of stimulating epidermal growth factor (EGF) and inhibiting mitomycin c. Therefore, digital holograms were recorded continuously every thirty minutes. Morphological changes including cell thickness, dry mass and tissue density were analyzed by data from quantitative digital holographic phase microscopy. Stimulation of Caco-2 cells with EGF or mitomycin c resulted in significant morphological changes during wound healing compared to control cells. In conclusion, DHM allows accurate, stain-free and continuous multimodal quantitative monitoring of wound healing in vitro and could be a promising new technique for assessment of wound healing.
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Affiliation(s)
- Dominik Bettenworth
- Department of Medicine B, University Hospital Münster, Münster, Germany
- * E-mail: (DB); (BK)
| | - Philipp Lenz
- Department of Medicine B, University Hospital Münster, Münster, Germany
| | | | - Markus Brückner
- Department of Medicine B, University Hospital Münster, Münster, Germany
| | - Steffi Ketelhut
- Center for Biomedical Optics and Photonics, University of Münster, Münster, Germany
- Biomedical Technology Center, University of Münster, Münster, Germany
| | - Dirk Domagk
- Department of Medicine B, University Hospital Münster, Münster, Germany
| | - Björn Kemper
- Center for Biomedical Optics and Photonics, University of Münster, Münster, Germany
- Biomedical Technology Center, University of Münster, Münster, Germany
- * E-mail: (DB); (BK)
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39
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Digital holographic microscopy for non-invasive monitoring of cell cycle arrest in L929 cells. PLoS One 2014; 9:e106546. [PMID: 25208094 PMCID: PMC4160194 DOI: 10.1371/journal.pone.0106546] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Accepted: 08/08/2014] [Indexed: 01/18/2023] Open
Abstract
Digital holographic microscopy (DHM) has emerged as a powerful non-invasive tool for cell analysis. It has the capacity to analyse multiple parameters simultaneously, such as cell- number, confluence and phase volume. This is done while cells are still adhered and growing in their culture flask. The aim of this study was to investigate whether DHM was able to monitor drug-induced cell cycle arrest in cultured cells and thus provide a non-disruptive alternative to flow cytometry. DHM parameters from G1 and G2/M cell cycle arrested L929 mouse fibroblast cells were collected. Cell cycle arrest was verified with flow cytometry. This study shows that DHM is able to monitor phase volume changes corresponding to either a G1 or G2/M cell cycle arrest. G1-phase arrest with staurosporine correlated with a decrease in the average cell phase volume and G2/M-phase arrest with colcemid and etoposide correlated with an increase in the average cell phase volume. Importantly, DHM analysis of average cell phase volume was of comparable accuracy to flow cytometric measurement of cell cycle phase distribution as recorded following dose-dependent treatment with etoposide. Average cell phase volume changes in response to treatment with cell cycle arresting compounds could therefore be used as a DHM marker for monitoring cell cycle arrest in cultured mammalian cells.
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Chan CJ, Whyte G, Boyde L, Salbreux G, Guck J. Impact of heating on passive and active biomechanics of suspended cells. Interface Focus 2014; 4:20130069. [PMID: 24748957 PMCID: PMC3982451 DOI: 10.1098/rsfs.2013.0069] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
A cell is a complex material whose mechanical properties are essential for its normal functions. Heating can have a dramatic effect on these mechanical properties, similar to its impact on the dynamics of artificial polymer networks. We investigated such mechanical changes by the use of a microfluidic optical stretcher, which allowed us to probe cell mechanics when the cells were subjected to different heating conditions at different time scales. We find that HL60/S4 myeloid precursor cells become mechanically more compliant and fluid-like when subjected to either a sudden laser-induced temperature increase or prolonged exposure to higher ambient temperature. Above a critical temperature of 52 ± 1°C, we observed active cell contraction, which was strongly correlated with calcium influx through temperature-sensitive transient receptor potential vanilloid 2 (TRPV2) ion channels, followed by a subsequent expansion in cell volume. The change from passive to active cellular response can be effectively described by a mechanical model incorporating both active stress and viscoelastic components. Our work highlights the role of TRPV2 in regulating the thermomechanical response of cells. It also offers insights into how cortical tension and osmotic pressure govern cell mechanics and regulate cell-shape changes in response to heat and mechanical stress.
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Affiliation(s)
- C. J. Chan
- Cavendish Laboratory, Department of Physics, University of Cambridge, Cambridge, UK
- Biotechnology Center, Technische Universität Dresden, Dresden, Germany
| | - G. Whyte
- Department of Physics and Institute of Medical Biotechnology, University of Erlangen-Nuremberg, Erlangen, Germany
| | - L. Boyde
- Cavendish Laboratory, Department of Physics, University of Cambridge, Cambridge, UK
| | - G. Salbreux
- Max Planck Institute for the Physics of Complex Systems, Dresden, Germany
| | - J. Guck
- Cavendish Laboratory, Department of Physics, University of Cambridge, Cambridge, UK
- Biotechnology Center, Technische Universität Dresden, Dresden, Germany
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Chalut KJ, Höpfler M, Lautenschläger F, Boyde L, Chan CJ, Ekpenyong A, Martinez-Arias A, Guck J. Chromatin decondensation and nuclear softening accompany Nanog downregulation in embryonic stem cells. Biophys J 2012. [PMID: 23200040 DOI: 10.1016/j.bpj.2012.10.015] [Citation(s) in RCA: 113] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The interplay between epigenetic modification and chromatin compaction is implicated in the regulation of gene expression, and it comprises one of the most fascinating frontiers in cell biology. Although a complete picture is still lacking, it is generally accepted that the differentiation of embryonic stem (ES) cells is accompanied by a selective condensation into heterochromatin with concomitant gene silencing, leaving access only to lineage-specific genes in the euchromatin. ES cells have been reported to have less condensed chromatin, as they are capable of differentiating into any cell type. However, pluripotency itself-even prior to differentiation-is a split state comprising a naïve state and a state in which ES cells prime for differentiation. Here, we show that naïve ES cells decondense their chromatin in the course of downregulating the pluripotency marker Nanog before they initiate lineage commitment. We used fluorescence recovery after photobleaching, and histone modification analysis paired with a novel, to our knowledge, optical stretching method, to show that ES cells in the naïve state have a significantly stiffer nucleus that is coupled to a globally more condensed chromatin state. We link this biophysical phenotype to coinciding epigenetic differences, including histone methylation, and show a strong correlation of chromatin condensation and nuclear stiffness with the expression of Nanog. Besides having implications for transcriptional regulation and embryonic cell sorting and suggesting a putative mechanosensing mechanism, the physical differences point to a system-level regulatory role of chromatin in maintaining pluripotency in embryonic development.
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Affiliation(s)
- Kevin J Chalut
- Cavendish Laboratory, Department of Physics, University of Cambridge, Cambridge, UK.
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