1
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Henderson J, Havranek O, Ma MCJ, Herman V, Kupcova K, Chrbolkova T, Pacheco-Blanco M, Wang Z, Comer JM, Zal T, Davis RE. Detecting Förster resonance energy transfer in living cells by conventional and spectral flow cytometry. Cytometry A 2022; 101:818-834. [PMID: 34128311 DOI: 10.1002/cyto.a.24472] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 05/31/2021] [Accepted: 06/07/2021] [Indexed: 01/27/2023]
Abstract
Assays based on Förster resonance energy transfer (FRET) can be used to study many processes in cell biology. Although this is most often done with microscopy for fluorescence detection, we report two ways to measure FRET in living cells by flow cytometry. Using a conventional flow cytometer and the "3-cube method" for intensity-based calculation of FRET efficiency, we measured the enzymatic activity of specific kinases in cells expressing a genetically-encoded reporter. For both AKT and protein kinase A, the method measured kinase activity in time-course, dose-response, and kinetic assays. Using the Cytek Aurora spectral flow cytometer, which applies linear unmixing to emission measured in multiple wavelength ranges, FRET from the same reporters was measured with greater single-cell precision, in real time and in the presence of other fluorophores. Results from gene-knockout studies suggested that spectral flow cytometry might enable the sorting of cells on the basis of FRET. The methods we present provide convenient and flexible options for using FRET with flow cytometry in studies of cell biology.
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Affiliation(s)
- Jared Henderson
- Department of Lymphoma and Myeloma, The University of Texas-MD Anderson Cancer Center, Houston, Texas, USA
| | - Ondrej Havranek
- Department of Lymphoma and Myeloma, The University of Texas-MD Anderson Cancer Center, Houston, Texas, USA.,BIOCEV, First Faculty of Medicine, Charles University, Vestec, Czech Republic.,Department of Hematology, Charles University and General University Hospital, Prague, Czech Republic
| | - Man Chun John Ma
- Department of Lymphoma and Myeloma, The University of Texas-MD Anderson Cancer Center, Houston, Texas, USA
| | - Vaclav Herman
- BIOCEV, First Faculty of Medicine, Charles University, Vestec, Czech Republic.,Department of Hematology, Charles University and General University Hospital, Prague, Czech Republic
| | - Kristyna Kupcova
- BIOCEV, First Faculty of Medicine, Charles University, Vestec, Czech Republic
| | - Tereza Chrbolkova
- BIOCEV, First Faculty of Medicine, Charles University, Vestec, Czech Republic
| | | | - Zhiqiang Wang
- Department of Lymphoma and Myeloma, The University of Texas-MD Anderson Cancer Center, Houston, Texas, USA
| | - Justin M Comer
- Department of Lymphoma and Myeloma, The University of Texas-MD Anderson Cancer Center, Houston, Texas, USA
| | - Tomasz Zal
- Department of Leukemia, The University of Texas-MD Anderson Cancer Center, Houston, Texas, USA
| | - Richard Eric Davis
- Department of Lymphoma and Myeloma, The University of Texas-MD Anderson Cancer Center, Houston, Texas, USA.,Department of Translational Molecular Pathology, The University of Texas-MD Anderson Cancer Center, Houston, Texas, USA
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2
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Bene L, Damjanovich L. Spectral flow cytometric FRET: Towards a hyper dimensional flow cytometry. Cytometry A 2022; 101:468-473. [PMID: 35484961 DOI: 10.1002/cyto.a.24561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 04/11/2022] [Accepted: 04/19/2022] [Indexed: 11/07/2022]
Affiliation(s)
- László Bene
- Department of Surgery, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - László Damjanovich
- Department of Surgery, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
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3
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Lim J, Petersen M, Bunz M, Simon C, Schindler M. Flow cytometry based-FRET: basics, novel developments and future perspectives. Cell Mol Life Sci 2022; 79:217. [PMID: 35352201 PMCID: PMC8964568 DOI: 10.1007/s00018-022-04232-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 03/07/2022] [Indexed: 12/29/2022]
Abstract
Förster resonance energy transfer (FRET) is a widespread technology used to analyze and quantify protein interactions in multiple settings. While FRET is traditionally measured by microscopy, flow cytometry based-FRET is becoming popular within the last decade and more commonly used. Flow cytometry based-FRET offers the possibility to assess FRET in a short time-frame in a high number of cells thereby allowing stringent and statistically robust quantification of FRET in multiple samples. Furthermore, established, simple and easy to implement gating strategies facilitate the adaptation of flow cytometry based-FRET measurements to most common flow cytometers. We here summarize the basics of flow cytometry based-FRET, highlight recent novel developments in this field and emphasize on exciting future perspectives.
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Affiliation(s)
- JiaWen Lim
- Institute for Medical Virology and Epidemiology of Viral Diseases, University Hospital Tübingen, Tübingen, Germany
| | - Moritz Petersen
- Institute for Medical Virology and Epidemiology of Viral Diseases, University Hospital Tübingen, Tübingen, Germany
| | - Maximilian Bunz
- Institute for Medical Virology and Epidemiology of Viral Diseases, University Hospital Tübingen, Tübingen, Germany
| | - Claudia Simon
- Institute for Medical Virology and Epidemiology of Viral Diseases, University Hospital Tübingen, Tübingen, Germany
| | - Michael Schindler
- Institute for Medical Virology and Epidemiology of Viral Diseases, University Hospital Tübingen, Tübingen, Germany.
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4
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Samimi K, Guzman EC, Trier SM, Pham DL, Qian T, Skala MC. Time-domain single photon-excited autofluorescence lifetime for label-free detection of T cell activation. OPTICS LETTERS 2021; 46:2168-2171. [PMID: 33929445 PMCID: PMC8109150 DOI: 10.1364/ol.422445] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Accepted: 04/01/2021] [Indexed: 05/12/2023]
Abstract
Fluorescence lifetime imaging microscopy (FLIM) is a powerful technique, capable of label-free assessment of the metabolic state and function within single cells. The FLIM measurements of autofluorescence were recently shown to be sensitive to the functional state and subtype of T cells. Therefore, autofluorescence FLIM could improve cell manufacturing technologies for adoptive immunotherapy, which currently require a time-intensive process of cell labeling with fluorescent antibodies. However, current autofluorescence FLIM implementations are typically too slow, bulky, and prohibitively expensive for use in cell manufacturing pipelines. Here we report a single photon-excited confocal whole-cell autofluorescence system that uses fast field-programmable gate array-based time tagging electronics to achieve time-correlated single photon counting (TCSPC) of single-cell autofluorescence. The system includes simultaneous near-infrared bright-field imaging and is sensitive to variations in the fluorescence decay profile of the metabolic coenzyme NAD(P)H in human T cells due to the activation state. The classification of activated and quiescent T cells achieved high accuracy and precision (area under the receiver operating characteristic curve, AUC = 0.92). The lower-cost, higher acquisition speed, and resistance to pile-up effects at high photon flux compared to traditional multiphoton-excited FLIM and TCSPC implementations with similar SNR make this system attractive for integration into flow cytometry, sorting, and quality control in cell manufacturing.
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Affiliation(s)
| | | | | | - Dan L. Pham
- Morgridge Institute for Research, Madison, WI 53715
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI 53706
| | | | - Melissa C. Skala
- Morgridge Institute for Research, Madison, WI 53715
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI 53706
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5
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Lifetime encoding in flow cytometry for bead-based sensing of biomolecular interaction. Sci Rep 2020; 10:19477. [PMID: 33173064 PMCID: PMC7655863 DOI: 10.1038/s41598-020-76150-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 10/07/2020] [Indexed: 12/19/2022] Open
Abstract
To demonstrate the potential of time-resolved flow cytometry (FCM) for bioanalysis, clinical diagnostics, and optically encoded bead-based assays, we performed a proof-of-principle study to detect biomolecular interactions utilizing fluorescence lifetime (LT)-encoded micron-sized polymer beads bearing target-specific bioligands and a recently developed prototype lifetime flow cytometer (LT-FCM setup). This instrument is equipped with a single excitation light source and different fluorescence detectors, one operated in the photon-counting mode for time-resolved measurements of fluorescence decays and three detectors for conventional intensity measurements in different spectral windows. First, discrimination of bead-bound biomolecules was demonstrated in the time domain exemplarily for two targets, Streptavidin (SAv) and the tumor marker human chorionic gonadotropin (HCG). In a second step, the determination of biomolecule concentration levels was addressed representatively for the inflammation-related biomarker tumor necrosis factor (TNF-α) utilizing fluorescence intensity measurements in a second channel of the LT-FCM instrument. Our results underline the applicability of LT-FCM in the time domain for measurements of biomolecular interactions in suspension assays. In the future, the combination of spectral and LT encoding and multiplexing and the expansion of the time scale from the lower nanosecond range to the longer nanosecond and the microsecond region is expected to provide many distinguishable codes. This enables an increasing degree of multiplexing which could be attractive for high throughput screening applications.
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6
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Nichani K, Li J, Suzuki M, Houston JP. Evaluation of Caspase-3 Activity During Apoptosis with Fluorescence Lifetime-Based Cytometry Measurements and Phasor Analyses. Cytometry A 2020; 97:1265-1275. [PMID: 32790129 PMCID: PMC7738394 DOI: 10.1002/cyto.a.24207] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 07/30/2020] [Accepted: 08/07/2020] [Indexed: 12/12/2022]
Abstract
Caspase-3 is a well-described protease with many roles that impact the fate of a cell. During apoptosis, caspase-3 acts as an executioner caspase with important proteolytic functions that lead to the final stages of programmed cell death. Owing to this key role, caspase-3 is exploited intracellularly as a target of control of apoptosis for therapeutic outcomes. Yet the activation of caspase-3 during apoptosis is challenged by other roles and functions (e.g., paracrine signaling). This brief report presents a way to track caspase-3 levels using a flow cytometer that measures excited state fluorescence lifetimes and a signal processing approach that leads to a graphical phasor-based interpretation. An established Förster resonance energy transfer (FRET) bioprobe was used for this test; the connected donor and acceptor fluorophore is cleavable by caspase-3 during apoptosis induction. With the cell-by-cell decay kinetic data and phasor analyses we generate a caspase activation trajectory, which is used to interpret activation throughout apoptosis. When lifetime-based cytometry is combined with a FRET bioprobe and phasor analyses, enzyme activation can be simplified and quantified with phase and modulation data. We envision extrapolating this approach to high content screening, and reinforce the power of phasor approaches with cytometric data. Analyses such as these can be used to cluster cells by their phase and modulation "lifetime fingerprint" when the intracellular fluorescent probe is utilized as a sensor of enzyme activity. © 2020 The Authors. Cytometry Part A published by Wiley Periodicals LLC on behalf of International Society for Advancement of Cytometry.
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Affiliation(s)
- Kapil Nichani
- Department of Chemical & Materials EngineeringNew Mexico State UniversityLas CrucesNew MexicoUSA
| | - Jianzhi Li
- Department of Chemical & Materials EngineeringNew Mexico State UniversityLas CrucesNew MexicoUSA
| | - Miho Suzuki
- Department of Functional Materials and ScienceGraduate School of Science and Engineering, Saitama UniversitySaitama338‐8570Japan
| | - Jessica P. Houston
- Department of Chemical & Materials EngineeringNew Mexico State UniversityLas CrucesNew MexicoUSA
- Department of Functional Materials and ScienceGraduate School of Science and Engineering, Saitama UniversitySaitama338‐8570Japan
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7
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Colacurci N, Schettino MT, Grimaldi V, De Luca FP, Mansueto G, Costa D, Cacciatore F, De Franciscis P, Napoli C. Flow Cytometry Characterization of Pluripotent Transmembrane Glycoproteins on Resident Cervix Uteri Cells in Patients Screened for Cervical Cancer. Cancer Invest 2020; 38:228-239. [PMID: 32208057 DOI: 10.1080/07357907.2020.1742349] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The aim of this study was to characterize both by flow cytometry analysis and immunohistochemistry cervix uteri cells of nulliparous women screened for cervical intraepithelial neoplasia (CIN) in comparison to a group without CIN by using mesenchymal stem cell-like and hematopoietic lineage markers. A significant expression for CD29, CD38, HLA-I, and HLA-II was correlated positively to the CIN degree and it was more relevant in patients positive for human papilloma virus (HPV). Thus, identification and detailed characterization of pluripotent resident in uteri cells could be a promising therapeutic target.
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Affiliation(s)
- Nicola Colacurci
- Obstetrics and Gynecology, Department of Woman, Child and General and Specialized Surgery, University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Maria Teresa Schettino
- Obstetrics and Gynecology, Department of Woman, Child and General and Specialized Surgery, University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Vincenzo Grimaldi
- Department of Advanced Medical and Surgical Sciences. U.O.C. Division of Clinical Immunology, Immunohematology, Transfusion Medicine and Transplant Immunology (SIMT), Regional Reference Laboratory of Transplant Immunology (LIT), University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Francesco Paolo De Luca
- Department of Advanced Medical and Surgical Sciences. U.O.C. Division of Clinical Immunology, Immunohematology, Transfusion Medicine and Transplant Immunology (SIMT), Regional Reference Laboratory of Transplant Immunology (LIT), University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Gelsomina Mansueto
- Department of Advanced Biomedical Sciences, Legal Medicine Unit, Federico II University of Naples, Naples, Italy
| | - Dario Costa
- Department of Advanced Medical and Surgical Sciences. U.O.C. Division of Clinical Immunology, Immunohematology, Transfusion Medicine and Transplant Immunology (SIMT), Regional Reference Laboratory of Transplant Immunology (LIT), University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Francesco Cacciatore
- Department of Translational Medical Sciences, Federico II University of Naples, Naples, Italy
| | - Pasquale De Franciscis
- Obstetrics and Gynecology, Department of Woman, Child and General and Specialized Surgery, University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Claudio Napoli
- Department of Advanced Medical and Surgical Sciences. U.O.C. Division of Clinical Immunology, Immunohematology, Transfusion Medicine and Transplant Immunology (SIMT), Regional Reference Laboratory of Transplant Immunology (LIT), University of Campania "Luigi Vanvitelli", Naples, Italy
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8
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Kage D, Hoffmann K, Nifontova G, Krivenkov V, Sukhanova A, Nabiev I, Resch-Genger U. Tempo-spectral multiplexing in flow cytometry with lifetime detection using QD-encoded polymer beads. Sci Rep 2020; 10:653. [PMID: 31959852 PMCID: PMC6971033 DOI: 10.1038/s41598-019-56938-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Accepted: 12/18/2019] [Indexed: 01/09/2023] Open
Abstract
Semiconductor quantum dots (QDs) embedded into polymer microbeads are known to be very attractive emitters for spectral multiplexing and colour encoding. Their luminescence lifetimes or decay kinetics have been, however, rarely exploited as encoding parameter, although they cover time ranges which are not easily accessible with other luminophores. We demonstrate here the potential of QDs made from II/VI semiconductors with luminescence lifetimes of several 10 ns to expand the lifetime range of organic encoding luminophores in multiplexing applications using time-resolved flow cytometry (LT-FCM). For this purpose, two different types of QD-loaded beads were prepared and characterized by photoluminescence measurements on the ensemble level and by single-particle confocal laser scanning microscopy. Subsequently, these lifetime-encoded microbeads were combined with dye-encoded microparticles in systematic studies to demonstrate the potential of these QDs to increase the number of lifetime codes for lifetime multiplexing and combined multiplexing in the time and colour domain (tempo-spectral multiplexing). These studies were done with a recently developed novel luminescence lifetime flow cytometer (LT-FCM setup) operating in the time-domain, that presents an alternative to reports on phase-sensitive lifetime detection in flow cytometry.
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Affiliation(s)
- Daniel Kage
- Federal Institute for Materials Research and Testing (BAM), Biophotonics Division 1.2, Richard-Willstätter-Str. 11, D-12489, Berlin, Germany.,Department of Physics, Humboldt-Universität zu Berlin, Newtonstr. 15, D-12489, Berlin, Germany
| | - Katrin Hoffmann
- Federal Institute for Materials Research and Testing (BAM), Biophotonics Division 1.2, Richard-Willstätter-Str. 11, D-12489, Berlin, Germany
| | - Galina Nifontova
- Laboratory of Nano-bioengineering, National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), 115409, Moscow, Russian Federation
| | - Victor Krivenkov
- Laboratory of Nano-bioengineering, National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), 115409, Moscow, Russian Federation
| | - Alyona Sukhanova
- Laboratoire de Recherche en Nanosciences, LRN-EA4682, Université de Reims Champagne-Ardenne, 51100, Reims, France
| | - Igor Nabiev
- Laboratory of Nano-bioengineering, National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), 115409, Moscow, Russian Federation.,Laboratoire de Recherche en Nanosciences, LRN-EA4682, Université de Reims Champagne-Ardenne, 51100, Reims, France.,Sechenov First Moscow State Medical University, 119991, Moscow, Russian Federation
| | - Ute Resch-Genger
- Federal Institute for Materials Research and Testing (BAM), Biophotonics Division 1.2, Richard-Willstätter-Str. 11, D-12489, Berlin, Germany.
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9
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Haynes EP, Rajendran M, Henning CK, Mishra A, Lyon AM, Tantama M. Quantifying Acute Fuel and Respiration Dependent pH Homeostasis in Live Cells Using the mCherryTYG Mutant as a Fluorescence Lifetime Sensor. Anal Chem 2019; 91:8466-8475. [PMID: 31247720 PMCID: PMC6623984 DOI: 10.1021/acs.analchem.9b01562] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Intracellular pH plays a key role in physiology, and its measurement in living specimens remains a crucial task in biology. Fluorescent protein-based pH sensors have gained widespread use, but there is limited spectral diversity for multicolor detection, and it remains a challenge to measure absolute pH values. Here we demonstrate that mCherryTYG is an excellent fluorescence lifetime pH sensor that significantly expands the modalities available for pH quantification in live cells. We first report the 1.09 Å X-ray crystal structure of mCherryTYG, exhibiting a fully matured chromophore. We next determine that it has an extraordinarily large dynamic range with a 2 ns lifetime change from pH 5.5 to 9.0. Critically, we find that the sensor maintains a p Ka of 6.8 independent of environment, whether as the purified protein in solution or expressed in live cells. Furthermore, the lifetime measurements are robustly independent of total fluorescence intensity and scatter. We demonstrate that mCherryTYG is a highly effective sensor using time-resolved fluorescence spectroscopy on live-cell suspensions, which has been previously overlooked as an easily accessible approach for quantifying intracellular pH. As a red fluorescent sensor, we also demonstrate that mCherryTYG is spectrally compatible with the ATeam sensor and EGFP for simultaneous dual-color measurements of intracellular pH, ATP, and extracellular pH. In a proof-of-concept, we quantify acute respiration-dependent pH homeostasis that exhibits a stoichiometric relationship with the ATP-generating capacity of the carbon fuel choice in E. coli. Broadly speaking, our work presents a previously unemployed methodology that will greatly facilitate continuous pH quantification.
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Affiliation(s)
- Emily P. Haynes
- Department of Chemistry, Purdue University, 560 Oval Drive, Box 68, West Lafayette, IN 47907, USA
| | - Megha Rajendran
- Department of Chemistry, Purdue University, 560 Oval Drive, Box 68, West Lafayette, IN 47907, USA
- Institute for Integrative Neuroscience, Purdue University, 560 Oval Drive, Box 68, West Lafayette, IN 47907, USA
| | | | | | - Angeline M. Lyon
- Department of Chemistry, Purdue University, 560 Oval Drive, Box 68, West Lafayette, IN 47907, USA
- Institute of Inflammation, Immunology, and Infectious Disease, Purdue University, 560 Oval Drive, Box 68, West Lafayette, IN 47907, USA
- Department of Biological Sciences, Purdue University, 560 Oval Drive, Box 68, West Lafayette, IN 47907, USA
| | - Mathew Tantama
- Department of Chemistry, Purdue University, 560 Oval Drive, Box 68, West Lafayette, IN 47907, USA
- Institute for Integrative Neuroscience, Purdue University, 560 Oval Drive, Box 68, West Lafayette, IN 47907, USA
- Institute of Inflammation, Immunology, and Infectious Disease, Purdue University, 560 Oval Drive, Box 68, West Lafayette, IN 47907, USA
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10
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Hochreiter B, Kunze M, Moser B, Schmid JA. Advanced FRET normalization allows quantitative analysis of protein interactions including stoichiometries and relative affinities in living cells. Sci Rep 2019; 9:8233. [PMID: 31160659 PMCID: PMC6547726 DOI: 10.1038/s41598-019-44650-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Accepted: 05/20/2019] [Indexed: 12/31/2022] Open
Abstract
FRET (Fluorescence Resonance Energy Transfer) measurements are commonly applied to proof protein-protein interactions. However, standard methods of live cell FRET microscopy and signal normalization only allow a principle assessment of mutual binding and are unable to deduce quantitative information of the interaction. We present an evaluation and normalization procedure for 3-filter FRET measurements, which reflects the process of complex formation by plotting FRET-saturation curves. The advantage of this approach relative to traditional signal normalizations is demonstrated by mathematical simulations. Thereby, we also identify the contribution of critical parameters such as the total amount of donor and acceptor molecules and their molar ratio. When combined with a fitting procedure, this normalization facilitates the extraction of key properties of protein complexes such as the interaction stoichiometry or the apparent affinity of the binding partners. Finally, the feasibility of our method is verified by investigating three exemplary protein complexes. Altogether, our approach offers a novel method for a quantitative analysis of protein interactions by 3-filter FRET microscopy, as well as flow cytometry. To facilitate the application of this method, we created macros and routines for the programs ImageJ, R and MS-Excel, which we make publicly available.
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Affiliation(s)
- Bernhard Hochreiter
- Medical University Vienna, Center for Physiology and Pharmacology, Institute for Vascular Biology and Thrombosis Research, Vienna, Austria
| | - Markus Kunze
- Medical University Vienna, Center for Brain Research, Department of Pathobiology of the Nervous System, Vienna, Austria
| | - Bernhard Moser
- Medical University Vienna, Center for Physiology and Pharmacology, Institute for Vascular Biology and Thrombosis Research, Vienna, Austria
| | - Johannes A Schmid
- Medical University Vienna, Center for Physiology and Pharmacology, Institute for Vascular Biology and Thrombosis Research, Vienna, Austria.
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11
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Shrirao AB, Fritz Z, Novik EM, Yarmush GM, Schloss RS, Zahn JD, Yarmush ML. Microfluidic flow cytometry: The role of microfabrication methodologies, performance and functional specification. TECHNOLOGY 2018; 6:1-23. [PMID: 29682599 PMCID: PMC5907470 DOI: 10.1142/s2339547818300019] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Flow cytometry is an invaluable tool utilized in modern biomedical research and clinical applications requiring high throughput, high resolution particle analysis for cytometric characterization and/or sorting of cells and particles as well as for analyzing results from immunocytometric assays. In recent years, research has focused on developing microfluidic flow cytometers with the motivation of creating smaller, less expensive, simpler, and more autonomous alternatives to conventional flow cytometers. These devices could ideally be highly portable, easy to operate without extensive user training, and utilized for research purposes and/or point-of-care diagnostics especially in limited resource facilities or locations requiring on-site analyses. However, designing a device that fulfills the criteria of high throughput analysis, automation and portability, while not sacrificing performance is not a trivial matter. This review intends to present the current state of the field and provide considerations for further improvement by focusing on the key design components of microfluidic flow cytometers. The recent innovations in particle focusing and detection strategies are detailed and compared. This review outlines performance matrix parameters of flow cytometers that are interdependent with each other, suggesting trade offs in selection based on the requirements of the applications. The ongoing contribution of microfluidics demonstrates that it is a viable technology to advance the current state of flow cytometry and develop automated, easy to operate and cost-effective flow cytometers.
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Affiliation(s)
- Anil B Shrirao
- Department of Biomedical Engineering, Rutgers University, 599, Taylor Road, Piscataway, NJ 08854
| | - Zachary Fritz
- Department of Biomedical Engineering, Rutgers University, 599, Taylor Road, Piscataway, NJ 08854
| | - Eric M Novik
- Hurel Corporation, 671, Suite B, U.S. Highway 1, North Brunswick, NJ 08902
| | - Gabriel M Yarmush
- Department of Biomedical Engineering, Rutgers University, 599, Taylor Road, Piscataway, NJ 08854
| | - Rene S Schloss
- Department of Biomedical Engineering, Rutgers University, 599, Taylor Road, Piscataway, NJ 08854
| | - Jeffrey D Zahn
- Department of Biomedical Engineering, Rutgers University, 599, Taylor Road, Piscataway, NJ 08854
| | - Martin L Yarmush
- Department of Biomedical Engineering, Rutgers University, 599, Taylor Road, Piscataway, NJ 08854
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