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Belashov AV, Zhikhoreva AA, Salova AV, Belyaeva TN, Litvinov IK, Kornilova ES, Semenova IV, Vasyutinskii OS. Automatic segmentation of lysosomes and analysis of intracellular pH with Radachlorin photosensitizer and FLIM. Biochem Biophys Res Commun 2024; 710:149835. [PMID: 38574457 DOI: 10.1016/j.bbrc.2024.149835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Revised: 03/17/2024] [Accepted: 03/25/2024] [Indexed: 04/06/2024]
Abstract
We report application of the fluorescence lifetime imaging microscopy (FLIM) for analysis of distributions of intracellular acidity using a chlorin-e6 based photosensitizer Radachlorin. An almost two-fold increase of the photosensitizer fluorescence lifetime in alkaline microenvironments as compared to acidic ones allowed for clear distinguishing between acidic and alkaline intracellular structures. Clusterization of a phasor plot calculated from fits of the FLIM raw data by two Gaussian distributions provided accurate automatic segmentation of lysosomes featuring acidic contents. The approach was validated in colocalization experiments with LysoTracker fluorescence in living cells of four established lines. The dependence of photosensitizer fluorescence lifetime on microenvironment acidity allowed for estimation of pH inside the cells, except for the nuclei, where photosensitizer does not penetrate. The developed method is promising for combined application of the photosensitizer for both photodynamic treatment and diagnostics.
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Affiliation(s)
- A V Belashov
- Ioffe Institute, Russian Academy of Sciences, 26, Polytekhnicheskaya, St.Petersburg, 194021, Russia
| | - A A Zhikhoreva
- Ioffe Institute, Russian Academy of Sciences, 26, Polytekhnicheskaya, St.Petersburg, 194021, Russia
| | - A V Salova
- Institute of Cytology, Russian Academy of Sciences, Tikhoretsky Pr., 4, St. Petersburg, 194064, Russia
| | - T N Belyaeva
- Institute of Cytology, Russian Academy of Sciences, Tikhoretsky Pr., 4, St. Petersburg, 194064, Russia
| | - I K Litvinov
- Institute of Cytology, Russian Academy of Sciences, Tikhoretsky Pr., 4, St. Petersburg, 194064, Russia
| | - E S Kornilova
- Institute of Cytology, Russian Academy of Sciences, Tikhoretsky Pr., 4, St. Petersburg, 194064, Russia
| | - I V Semenova
- Ioffe Institute, Russian Academy of Sciences, 26, Polytekhnicheskaya, St.Petersburg, 194021, Russia.
| | - O S Vasyutinskii
- Ioffe Institute, Russian Academy of Sciences, 26, Polytekhnicheskaya, St.Petersburg, 194021, Russia
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2
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Kostyuk AI, Rapota DD, Morozova KI, Fedotova AA, Jappy D, Semyanov AV, Belousov VV, Brazhe NA, Bilan DS. Modern optical approaches in redox biology: Genetically encoded sensors and Raman spectroscopy. Free Radic Biol Med 2024; 217:68-115. [PMID: 38508405 DOI: 10.1016/j.freeradbiomed.2024.03.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Revised: 02/10/2024] [Accepted: 03/13/2024] [Indexed: 03/22/2024]
Abstract
The objective of the current review is to summarize the current state of optical methods in redox biology. It consists of two parts, the first is dedicated to genetically encoded fluorescent indicators and the second to Raman spectroscopy. In the first part, we provide a detailed classification of the currently available redox biosensors based on their target analytes. We thoroughly discuss the main architecture types of these proteins, the underlying engineering strategies for their development, the biochemical properties of existing tools and their advantages and disadvantages from a practical point of view. Particular attention is paid to fluorescence lifetime imaging microscopy as a possible readout technique, since it is less prone to certain artifacts than traditional intensiometric measurements. In the second part, the characteristic Raman peaks of the most important redox intermediates are listed, and examples of how this knowledge can be implemented in biological studies are given. This part covers such fields as estimation of the redox states and concentrations of Fe-S clusters, cytochromes, other heme-containing proteins, oxidative derivatives of thiols, lipids, and nucleotides. Finally, we touch on the issue of multiparameter imaging, in which biosensors are combined with other visualization methods for simultaneous assessment of several cellular parameters.
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Affiliation(s)
- Alexander I Kostyuk
- M.M. Shemyakin and Yu.A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, 117997, Russia; Pirogov Russian National Research Medical University, 117997, Moscow, Russia
| | - Diana D Rapota
- M.M. Shemyakin and Yu.A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, 117997, Russia
| | - Kseniia I Morozova
- Faculty of Biology, M.V. Lomonosov Moscow State University, Moscow, 119234, Russia
| | - Anna A Fedotova
- M.M. Shemyakin and Yu.A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, 117997, Russia; Faculty of Biology, M.V. Lomonosov Moscow State University, Moscow, 119234, Russia
| | - David Jappy
- Federal Center of Brain Research and Neurotechnologies, Federal Medical Biological Agency, Moscow, 117997, Russia
| | - Alexey V Semyanov
- M.M. Shemyakin and Yu.A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, 117997, Russia; Faculty of Biology, M.V. Lomonosov Moscow State University, Moscow, 119234, Russia; Sechenov First Moscow State Medical University, Moscow, 119435, Russia; College of Medicine, Jiaxing University, Jiaxing, Zhejiang Province, 314001, China
| | - Vsevolod V Belousov
- M.M. Shemyakin and Yu.A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, 117997, Russia; Pirogov Russian National Research Medical University, 117997, Moscow, Russia; Federal Center of Brain Research and Neurotechnologies, Federal Medical Biological Agency, Moscow, 117997, Russia; Life Improvement by Future Technologies (LIFT) Center, Skolkovo, Moscow, 143025, Russia
| | - Nadezda A Brazhe
- M.M. Shemyakin and Yu.A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, 117997, Russia; Faculty of Biology, M.V. Lomonosov Moscow State University, Moscow, 119234, Russia.
| | - Dmitry S Bilan
- M.M. Shemyakin and Yu.A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, 117997, Russia; Pirogov Russian National Research Medical University, 117997, Moscow, Russia.
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Clayton AHA. Photobleaching FRET-FLIM-ICS for quaternary structure quantification on cells. Theory and simulations. Biochim Biophys Acta Gen Subj 2024; 1868:130618. [PMID: 38621595 DOI: 10.1016/j.bbagen.2024.130618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 04/04/2024] [Accepted: 04/12/2024] [Indexed: 04/17/2024]
Abstract
The oligomerization of proteins is an important biological control mechanism and has several functions in activity and stability of enzymes, structural proteins, ion channels and transcription factors. The determination of the relevant oligomeric states in terms of geometry (spatial extent), oligomer size (monomer or dimer or oligomer) and affinity (amounts of monomer, dimer and oligomer) is a challenging biophysical problem. Förster resonance energy transfer and fluorescence fluctuation spectroscopy are powerful tools that are sensitive to proximity and oligomerization respectively. Here it is proposed to combine image-based lifetime-detected Forster resonance energy transfer with image correlation spectroscopy and photobleaching to determine distances, oligomer sizes and oligomer distributions. Simulations for simple oligomeric forms illustrate the potential to improve the discrimination between different quaternary states in the cellular milieu.
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Affiliation(s)
- Andrew H A Clayton
- Cell Biophysics Laboratory, Optical Sciences Centre, Department of Physics and Astronomy, School of Science, Computer, and Engineering Sciences, Swinburne University of Technology, Melbourne, Australia.
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Domínguez-Jurado E, Ripoll C, Lara-Sánchez A, Ocaña A, Vitórica-Yrezábal IJ, Bravo I, Alonso-Moreno C. Evaluation of heteroscorpionate ligands as scaffolds for the generation of Ruthenium(II) metallodrugs in breast cancer therapy. J Inorg Biochem 2024; 253:112486. [PMID: 38266323 DOI: 10.1016/j.jinorgbio.2024.112486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2023] [Revised: 01/14/2024] [Accepted: 01/15/2024] [Indexed: 01/26/2024]
Abstract
The modular synthesis of the heteroscorpionate core is explored as a tool for the rapid development of ruthenium-based therapeutic agents. Starting with a series of structurally diverse alcohol-NN ligands, a family of heteroscorpionate-based ruthenium derivatives was synthesized, characterized, and evaluated as an alternative to platinum therapy for breast cancer therapy. In vitro, the antitumoral activity of the novel derivatives was assessed in a series of breast cancer cell lines using UNICAM-1 and cisplatin as metallodrug control. Through this approach, a bimetallic heteroscorpionate-based metallodrug (RUSCO-2) was identified as the lead compound of the series with an IC50 value range as low as 3-5 μM. Notably, RUSCO-2 was found to be highly cytotoxic in TNBC cell lines, suggesting a mode of action independent of the receptor status of the cells. As a proof of concept and taking advantage of the luminescent properties of one of the complexes obtained, uptake was monitored in human breast cancer MCF7 cell lines by fluorescence lifetime imaging microscopy (FLIM) to reveal that the compound is evenly distributed in the cytoplasm and that the incorporation of the heteroscorpionate ligand protects it from aqueous processes, conversion in another entity, or the loss of the chloride group. Finally, ROS studies were conducted, lipophilicity was estimated, the chloride/water exchange was studied, and stability studies in simulated biological media were carried out to propose structure-activity relationships.
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Affiliation(s)
- Elena Domínguez-Jurado
- Universidad de Castilla-La Mancha, Unidad nanoDrug, Facultad de Farmacia de Albacete, 02008 Albacete, Spain; Universidad de Castilla-La Mancha, Departamento de Química Inorgánica, Orgánica y Bioquímica, Facultad de Ciencias y Tecnologías Químicas-Centro de Innovación en Química Avanzada (ORFEO-CINQA), Ciudad Real 13071, Spain
| | - Consuelo Ripoll
- Universidad de Castilla-La Mancha, Unidad nanoDrug, Facultad de Farmacia de Albacete, 02008 Albacete, Spain; Universidad de Castilla-La Mancha, Departamento de Química Física. Facultad de Farmacia de Albacete, Albacete 02071, Spain
| | - Agustín Lara-Sánchez
- Universidad de Castilla-La Mancha, Departamento de Química Inorgánica, Orgánica y Bioquímica, Facultad de Ciencias y Tecnologías Químicas-Centro de Innovación en Química Avanzada (ORFEO-CINQA), Ciudad Real 13071, Spain
| | - Alberto Ocaña
- Experimental Therapeutics Unit, Hospital clínico San Carlos, IdISSC and CIBERONC, Madrid, Spain
| | - Iñigo J Vitórica-Yrezábal
- Departamento de Química Inorgánica, Facultad de Ciencias, Universidad de Granada, Avda de Fuentenueva. s/n, 18071 Granada, Spain
| | - Iván Bravo
- Universidad de Castilla-La Mancha, Unidad nanoDrug, Facultad de Farmacia de Albacete, 02008 Albacete, Spain; Universidad de Castilla-La Mancha, Departamento de Química Física. Facultad de Farmacia de Albacete, Albacete 02071, Spain
| | - Carlos Alonso-Moreno
- Universidad de Castilla-La Mancha, Unidad nanoDrug, Facultad de Farmacia de Albacete, 02008 Albacete, Spain; Universidad de Castilla-La Mancha, Departamento de Química Inorgánica, Orgánica y Bioquímica, Facultad de Ciencias y Tecnologías Químicas-Centro de Innovación en Química Avanzada (ORFEO-CINQA), Ciudad Real 13071, Spain.
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5
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Diedrichsen RG, Vetri V, Prévost S, Foderà V, Nielsen HM. Carrier peptide interactions with liposome membranes induce reversible clustering by surface adsorption and shape deformation. J Colloid Interface Sci 2023; 650:1821-1832. [PMID: 37515972 DOI: 10.1016/j.jcis.2023.07.078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 06/27/2023] [Accepted: 07/12/2023] [Indexed: 07/31/2023]
Abstract
The cell-penetrating peptide penetratin and its analogues shuffle and penetramax have been used as carrier peptides for oral delivery of therapeutic peptides such as insulin. Their mechanism of action for this purpose is not fully understood but is believed to depend on the interactions of the peptide with the cell membrane. In the present study, peptide-liposome interactions were investigated using advanced biophysical techniques including small-angle neutron scattering and fluorescence lifetime imaging microscopy. Liposomes were used as a model system for the cell membrane. All the investigated carrier peptides induced liposome clustering at a specific peptide/lipid ratio. However, distinctively different types of membrane interactions were observed, as the liposome clustering was irreversible for penetratin, but fully or partly reversible for shuffle and penetramax, respectively. All three peptides were found to adsorb to the surface of the lipid bilayers, while only shuffle and penetramax led to shape deformation of the liposomes. Importantly, the peptide interactions did not disrupt the liposomes under any of the investigated conditions, which is advantageous for their application in drug delivery. This detailed insight on peptide-membrane interactions is important for understanding the mechanism of peptide-based excipients and the influence of peptide sequence modifications.
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Affiliation(s)
- Ragna Guldsmed Diedrichsen
- Center for Biopharmaceuticals and Biobarriers in Drug Delivery (BioDelivery), Department of Pharmacy, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark.
| | - Valeria Vetri
- Department of Physics and Chemistry, University of Palermo, Viale delle Scienze Ed. 18, 90128 Palermo, Italy.
| | - Sylvain Prévost
- Institut Laue-Langevin, 71 avenue des Martyrs, 38042 Grenoble Cedex 9, France.
| | - Vito Foderà
- Center for Biopharmaceuticals and Biobarriers in Drug Delivery (BioDelivery), Department of Pharmacy, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark.
| | - Hanne Mørck Nielsen
- Center for Biopharmaceuticals and Biobarriers in Drug Delivery (BioDelivery), Department of Pharmacy, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark.
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Abstract
Biomolecular condensates of ribonucleoproteins (RNPs) such as the transactivation response element (TAR) DNA-binding protein 43 (TDP-43) arise from liquid-liquid phase separation (LLPS) and play vital roles in various biological processes including the formation-dissolution of stress granules (SGs). These condensates are thought to be directly linked to neurodegenerative diseases, providing a depot of aggregation-prone proteins and serving as a cauldron of protein aggregation and fibrillation. Despite recent research efforts, biochemical processes and rearrangements within biomolecular condensates that trigger subsequent protein misfolding and aggregation remain to be elucidated. Fluorescence lifetime imaging microscopy (FLIM) provides a minimally intrusive high-sensitivity and high-resolution imaging method to monitor in-droplet spatiotemporal changes that initiate and lead to protein aggregation. In this chapter, we describe a FLIM application for characterizing chemical chaperone-assisted decoupling of TDP-43 liquid-liquid phase separation and aggregation/fibrillation, highlighting potential therapeutic strategies to combat pathological RNP-associated aggregates without compromising cellular stress responses.
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Affiliation(s)
- My Diem Quan
- Department of Pharmacology and Chemical Biology, Baylor College of Medicine, Houston, TX, USA
| | | | - Josephine C Ferreon
- Department of Pharmacology and Chemical Biology, Baylor College of Medicine, Houston, TX, USA.
| | - Allan Chris M Ferreon
- Department of Pharmacology and Chemical Biology, Baylor College of Medicine, Houston, TX, USA.
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Saini R, Rao C, Maji A, Mishra PM, Yadav A, Nandi CK, Ghosh K. Design and synthesis of novel palladium cyclometallate-based fluorescent probe: Studies on interaction with cell membrane by confocal and fluorescence lifetime imaging. J Inorg Biochem 2022; 237:112019. [PMID: 36244311 DOI: 10.1016/j.jinorgbio.2022.112019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2022] [Revised: 09/27/2022] [Accepted: 09/29/2022] [Indexed: 11/07/2022]
Abstract
Coordination complexes offer great potential as cellular imaging probes, which allow to examine specific cell organelle structures in their physiological conditions to better understand the biological system. Understanding the heterogeneous nature of the cell membrane could unveil details of their functionality. Here, we have developed a new anthracene conjugated fluorescent palladium(II) cyclometallate [PdL1Cl] where L1H = [2-(2- (anthracen-9-ylmethylene)-1-phenylhydrazineyl)pyridine] (H stands for dissociable proton), which not only specifically stains the cell membrane, but could be utilized to visualise the membrane by the confocal and fluorescence lifetime imaging microscopy (FLIM). This probe is unable to enter inside the cell as it did not pass through the cell membrane via diffusion or various organic and metal transporters. However, the great lipophilicity of fluorescein improves the interaction of the probe with the peptidoglycan layer of the cell membrane. Probable dissociation of chloride ion and formation of positively charged palladium complex resulted in staining the negatively charged cell membrane. The 3D confocal imaging clearly expressed sole membrane staining by the probe. The probe efficiently stains both cancer cells (HeLa and MCF-7 cell lines) and normal cell (HEK 293 T), confirming the universality of the probe in membrane staining.
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Affiliation(s)
- Rahul Saini
- Department of Chemistry and Department of BioScience and BioEngineering, Indian Institute of Technology, Roorkee, Roorkee 247667, Uttarakhand, India
| | - Chethana Rao
- School of Basic Sciences, Indian Institute of Technology, Mandi, Himachal Pradesh 175005, India; Advanced Materials Research Centre, Indian Institute of Technology, Mandi, Himachal Pradesh 175005, India
| | - Ankur Maji
- Department of Chemistry and Department of BioScience and BioEngineering, Indian Institute of Technology, Roorkee, Roorkee 247667, Uttarakhand, India
| | - Pushpendra M Mishra
- School of Basic Sciences, Indian Institute of Technology, Mandi, Himachal Pradesh 175005, India; Advanced Materials Research Centre, Indian Institute of Technology, Mandi, Himachal Pradesh 175005, India; BioX centre, Indian Institute of Technology, Mandi, Himachal Pradesh 175005, India
| | - Aditya Yadav
- School of Basic Sciences, Indian Institute of Technology, Mandi, Himachal Pradesh 175005, India; Advanced Materials Research Centre, Indian Institute of Technology, Mandi, Himachal Pradesh 175005, India
| | - Chayan K Nandi
- School of Basic Sciences, Indian Institute of Technology, Mandi, Himachal Pradesh 175005, India; Advanced Materials Research Centre, Indian Institute of Technology, Mandi, Himachal Pradesh 175005, India; BioX centre, Indian Institute of Technology, Mandi, Himachal Pradesh 175005, India
| | - Kaushik Ghosh
- Department of Chemistry and Department of BioScience and BioEngineering, Indian Institute of Technology, Roorkee, Roorkee 247667, Uttarakhand, India.
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Hameed S, Pan K, Su W, Trupp M, Mi L, Zhao J. Label-free detection and quantification of ultrafine particulate matter in lung and heart of mouse and evaluation of tissue injury. Part Fibre Toxicol 2022; 19:51. [PMID: 35883088 DOI: 10.1186/s12989-022-00493-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Accepted: 07/19/2022] [Indexed: 11/22/2022] Open
Abstract
While it is known that air borne ultrafine particulate matter (PM) may pass through the pulmonary circulation of blood at the alveolar level between lung and heart and cross the air-blood barrier, the mechanism and effects are not completely clear. In this study the imaging method fluorescence lifetime imaging microscopy is adopted for visualization with high spatial resolution and quantification of ultrafine PM particles in mouse lung and heart tissues. The results showed that the median numbers of particles in lung of mice exposed to ultrafine particulate matter of diameter less than 2.5 µm was about 2.0 times more than that in the filtered air (FA)-treated mice, and about 1.3 times more in heart of ultrafine PM-treated mice than in FA-treated mice. Interestingly, ultrafine PM particles were more abundant in heart than lung, likely due to how ultrafine PM particles are cleared by phagocytosis and transport via circulation from lungs. Moreover, heart tissues showed inflammation and amyloid deposition. The component analysis of concentrated airborne ultrafine PM particles suggested traffic exhausts and industrial emissions as predominant sources. Our results suggest association of ultrafine PM exposure to chronic lung and heart tissue injuries. The current study supports the contention that industrial air pollution is one of the causative factors for rising levels of chronic pulmonary and cardiac diseases.
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Ouyang Y, Liu Y, Wang ZM, Liu Z, Wu M. FLIM as a Promising Tool for Cancer Diagnosis and Treatment Monitoring. Nanomicro Lett 2021; 13:133. [PMID: 34138374 PMCID: PMC8175610 DOI: 10.1007/s40820-021-00653-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Accepted: 04/19/2021] [Indexed: 05/04/2023]
Abstract
Fluorescence lifetime imaging microscopy (FLIM) has been rapidly developed over the past 30 years and widely applied in biomedical engineering. Recent progress in fluorophore-dyed probe design has widened the application prospects of fluorescence. Because fluorescence lifetime is sensitive to microenvironments and molecule alterations, FLIM is promising for the detection of pathological conditions. Current cancer-related FLIM applications can be divided into three main categories: (i) FLIM with autofluorescence molecules in or out of a cell, especially with reduced form of nicotinamide adenine dinucleotide, and flavin adenine dinucleotide for cellular metabolism research; (ii) FLIM with Förster resonance energy transfer for monitoring protein interactions; and (iii) FLIM with fluorophore-dyed probes for specific aberration detection. Advancements in nanomaterial production and efficient calculation systems, as well as novel cancer biomarker discoveries, have promoted FLIM optimization, offering more opportunities for medical research and applications to cancer diagnosis and treatment monitoring. This review summarizes cutting-edge researches from 2015 to 2020 on cancer-related FLIM applications and the potential of FLIM for future cancer diagnosis methods and anti-cancer therapy development. We also highlight current challenges and provide perspectives for further investigation.
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Affiliation(s)
- Yuzhen Ouyang
- Hunan Provincial Tumor Hospital and the Affiliated Tumor Hospital of Xiangya Medical School, Central South University, Changsha, 410013, Hunan, People's Republic of China
- School of Physics and Electronics, Hunan Key Laboratory for Super-Microstructure and Ultrafast Process, Central South University, 932 South Lushan Road, Changsha, 410083, Hunan, People's Republic of China
- The Key Laboratory of Carcinogenesis of the Chinese Ministry of Health, The Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, Changsha, 410008, Hunan, People's Republic of China
| | - Yanping Liu
- School of Physics and Electronics, Hunan Key Laboratory for Super-Microstructure and Ultrafast Process, Central South University, 932 South Lushan Road, Changsha, 410083, Hunan, People's Republic of China.
- Shenzhen Research Institute of Central South University, A510a, Virtual University Building, Nanshan District, Southern District, High-tech Industrial Park, Yuehai Street, Shenzhen, People's Republic of China.
- State Key Laboratory of High-Performance Complex Manufacturing, Central South University, 932 South Lushan Road, Changsha, 410083, Hunan, People's Republic of China.
| | - Zhiming M Wang
- Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu, 610054, Sichuan, People's Republic of China
| | - Zongwen Liu
- School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, NSW, 2006, Australia.
| | - Minghua Wu
- Hunan Provincial Tumor Hospital and the Affiliated Tumor Hospital of Xiangya Medical School, Central South University, Changsha, 410013, Hunan, People's Republic of China.
- School of Physics and Electronics, Hunan Key Laboratory for Super-Microstructure and Ultrafast Process, Central South University, 932 South Lushan Road, Changsha, 410083, Hunan, People's Republic of China.
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10
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Bianchetti G, Ciccarone F, Ciriolo MR, De Spirito M, Pani G, Maulucci G. Label-free metabolic clustering through unsupervised pixel classification of multiparametric fluorescent images. Anal Chim Acta 2020; 1148:238173. [PMID: 33516373 DOI: 10.1016/j.aca.2020.12.048] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2020] [Revised: 12/21/2020] [Accepted: 12/22/2020] [Indexed: 12/21/2022]
Abstract
Autofluorescence microscopy is a promising label-free approach to characterize NADH and FAD metabolites in live cells, with potential applications in clinical practice. Although spectrally resolved lifetime imaging techniques can acquire multiparametric information about the biophysical and biochemical state of the metabolites, these data are evaluated at the whole-cell level, thus providing only limited insights in the activation of metabolic networks at the microscale. To overcome this issue, here we introduce an artificial intelligence-based analysis that, leveraging the multiparametric content of spectrally resolved lifetime images, allows to detect and classify, through an unsupervised learning approach, metabolic clusters, which are regions having almost uniform metabolic properties. This method contextually detects the cellular mitochondrial turnover and the metabolic activation state of intracellular compartments at the pixel level, described by two functions: the cytosolic activation state (CAF) and the mitochondrial activation state (MAF). This method was applied to investigate metabolic changes elicited in the breast cancer cell line MCF-7 by specific inhibitors of glycolysis and electron transport chain, and by the deregulation of a specific mitochondrial enzyme (ACO2) leading to defective aerobic metabolism associated with tumor growth. In this model, mitochondrial fraction undergoes to a 13% increase upon ACO2 overexpression and the MAF function changes abruptly by altering the metabolic state of about the 25% of the mitochondrial pixels.
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Affiliation(s)
- Giada Bianchetti
- Fondazione Policlinico Gemelli IRCSS, Rome, Italy; Department of Neuroscience, Section of Biophysics, Università Cattolica Del Sacro Cuore, Rome, Italy
| | - Fabio Ciccarone
- IRCCS San Raffaele Pisana, Department of Human Sciences and Promotion of the Quality of Life, San Raffaele Roma Open University, Rome, Italy
| | | | - Marco De Spirito
- Fondazione Policlinico Gemelli IRCSS, Rome, Italy; Department of Neuroscience, Section of Biophysics, Università Cattolica Del Sacro Cuore, Rome, Italy.
| | - Giovambattista Pani
- Fondazione Policlinico Gemelli IRCSS, Rome, Italy; Department of Translational Medicine and Surgery, Section of General Pathology, Università Cattolica Del Sacro Cuore, Rome, Italy
| | - Giuseppe Maulucci
- Fondazione Policlinico Gemelli IRCSS, Rome, Italy; Department of Neuroscience, Section of Biophysics, Università Cattolica Del Sacro Cuore, Rome, Italy.
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11
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van der Bent ML, Wansink DG, Brock R. Advanced Fluorescence Imaging to Distinguish Between Intracellular Fractions of Antisense Oligonucleotides. Methods Mol Biol 2020; 2063:119-38. [PMID: 31667767 DOI: 10.1007/978-1-0716-0138-9_10] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Antisense oligonucleotides (AON) have been intensively studied as tools in molecular cell biology and as novel therapeutics in various diseases over the past two decades. Especially cellular uptake and endosomal release of AONs are topics of interest, as these are crucial steps in reaching the subcellular AON target sites and achieving biological activity. We used cell-penetrating peptides (CPPs) to enhance uptake and endosomal release of AONs, and monitored these two processes and the subsequent fate of the AONs by advanced fluorescence microscopy in living cells. In this chapter, we discuss the use of automated time-lapse confocal laser scanning microscopy (CLSM) to follow AON uptake and trafficking in time, fluorescence lifetime imaging microscopy (FLIM) to distinguish between free and AON-bound fluorophore, and fluorescence correlation spectroscopy (FCS) to measure subcellular AON concentrations and molecular associations. Additionally, we expand on the analysis of these microscopy data.
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Alex A, Chaney EJ, Žurauskas M, Criley JM, Spillman DR, Hutchison PB, Li J, Marjanovic M, Frey S, Arp Z, Boppart SA. In vivo characterization of minipig skin as a model for dermatological research using multiphoton microscopy. Exp Dermatol 2020; 29:953-960. [PMID: 33311854 PMCID: PMC7725480 DOI: 10.1111/exd.14152] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2020] [Accepted: 06/29/2020] [Indexed: 12/24/2022]
Abstract
Minipig skin is one of the most widely used non-rodent animal skin models for dermatological research. A thorough characterization of minipig skin is essential for gaining deeper understanding of its structural and functional similarities with human skin. In this study, three-dimensional (3-D) in vivo images of minipig skin was obtained non-invasively using a multimodal optical imaging system capable of acquiring two-photon excited fluorescence (TPEF) and fluorescence lifetime imaging microscopy (FLIM) images simultaneously. The images of the structural features of different layers of the minipig skin were qualitatively and quantitatively compared with those of human skin. Label-free imaging of skin was possible due to the endogenous fluorescence and optical properties of various components in the skin such as keratin, nicotinamide adenine dinucleotide phosphate (NAD(P)H), melanin, elastin, and collagen. This study demonstrates the capability of optical biopsy techniques, such as TPEF and FLIM, for in vivo non-invasive characterization of cellular and functional features of minipig skin, and the optical image-based similarities of this commonly utilized model of human skin. These optical imaging techniques have the potential to become promising tools in dermatological research for developing a better understanding of animal skin models, and for aiding in translational pre-clinical to clinical studies.
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Affiliation(s)
- Aneesh Alex
- GSK Center for Optical Molecular Imaging, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
- GSK, Collegeville, PA, USA
| | - Eric J. Chaney
- GSK Center for Optical Molecular Imaging, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Mantas Žurauskas
- GSK Center for Optical Molecular Imaging, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Jennifer M. Criley
- Division of Animal Resources, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Darold R. Spillman
- GSK Center for Optical Molecular Imaging, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Phaedra B. Hutchison
- Division of Animal Resources, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Joanne Li
- GSK Center for Optical Molecular Imaging, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Marina Marjanovic
- GSK Center for Optical Molecular Imaging, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | | | | | - Stephen A. Boppart
- GSK Center for Optical Molecular Imaging, Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
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13
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Cvjetinovic J, Salimon AI, Novoselova MV, Sapozhnikov PV, Shirshin EA, Yashchenok AM, Kalinina OY, Korsunsky AM, Gorin DA. Photoacoustic and fluorescence lifetime imaging of diatoms. Photoacoustics 2020; 18:100171. [PMID: 32435586 PMCID: PMC7229289 DOI: 10.1016/j.pacs.2020.100171] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 01/20/2020] [Accepted: 02/25/2020] [Indexed: 06/11/2023]
Abstract
Photoacoustic and fluorescent methods are used intensely in biology and medicine. These approaches can also be used to investigate unicellular diatom algae that are extremely important for Earth's ecology. They are enveloped within silica frustules (exoskeletons), which can be used in drug delivery systems. Here, we report for the first time the successful application of photoacoustic (PA) and fluorescent visualization of diatoms. Chlorophyll a and c and fucoxanthin were found likely to be responsible for the photoacoustic effect in diatoms. The PA signal was obtained from gel drops containing diatoms and was found to increase with the diatom concentration. The fluorescence lifetime of the diatom chromophores ranged from 0.5 to 2 ns. The dynamic light scattering, absorbance, and SEM characterization techniques were also applied. The results were considered in combination to elucidate the nature of the photoacoustic signal. Possible biotechnological applications are proposed for the remote photoacoustic monitoring of algae.
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Affiliation(s)
- Julijana Cvjetinovic
- Center for Photonics and Quantum Materials, Skolkovo Institute of Science and Technology, 3 Nobelya Str., Moscow, 121205, Russia
| | - Alexey I. Salimon
- Center for Energy Science and Technology, Skolkovo Institute of Science and Technology, 3 Nobelya Str., Moscow, 121205, Russia
| | - Marina V. Novoselova
- Center for Photonics and Quantum Materials, Skolkovo Institute of Science and Technology, 3 Nobelya Str., Moscow, 121205, Russia
| | - Philipp V. Sapozhnikov
- Shirshov Institute of Oceanology of Russian Academy of Sciences, 36 Nakhimovsky Prospekt, Moscow, 117997, Russia
| | - Evgeny A. Shirshin
- Lomonosov Moscow State University, 1/2 Leninskiye Gory, Moscow, 119991, Russia
- Institute of Spectroscopy of the Russian Academy of Sciences, 5 Fizicheskaya Str., Troitsk, Moscow, 108840, Russia
| | - Alexey M. Yashchenok
- Center for Photonics and Quantum Materials, Skolkovo Institute of Science and Technology, 3 Nobelya Str., Moscow, 121205, Russia
| | - Olga Yu. Kalinina
- Faculty of Geography, Lomonosov Moscow State University, 1 Leninskiye Gory, Moscow, 119991, Russia
| | - Alexander M. Korsunsky
- Center for Energy Science and Technology, Skolkovo Institute of Science and Technology, 3 Nobelya Str., Moscow, 121205, Russia
- Department of Engineering Science, University of Oxford, Oxford, OX1 3PJ, United Kingdom
| | - Dmitry A. Gorin
- Center for Photonics and Quantum Materials, Skolkovo Institute of Science and Technology, 3 Nobelya Str., Moscow, 121205, Russia
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14
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Liang Z, Lou J, Scipioni L, Gratton E, Hinde E. Quantifying nuclear wide chromatin compaction by phasor analysis of histone Förster resonance energy transfer (FRET) in frequency domain fluorescence lifetime imaging microscopy (FLIM) data. Data Brief 2020; 30:105401. [PMID: 32300614 PMCID: PMC7152662 DOI: 10.1016/j.dib.2020.105401] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 03/03/2020] [Accepted: 03/03/2020] [Indexed: 11/30/2022] Open
Abstract
The nanometer spacing between nucleosomes throughout global chromatin organisation modulates local DNA template access, and through continuous dynamic rearrangements, regulates genome function [1]. However, given that nucleosome packaging occurs on a spatial scale well below the diffraction limit, real time observation of chromatin structure in live cells by optical microscopy has proved technically difficult, despite recent advances in live cell super resolution imaging [2]. One alternative solution to quantify chromatin structure in a living cell at the level of nucleosome proximity is to measure and spatially map Förster resonance energy transfer (FRET) between fluorescently labelled histones – the core protein of a nucleosome [3]. In recent work we established that the phasor approach to fluorescence lifetime imaging microscopy (FLIM) is a robust method for the detection of histone FRET which can quantify nuclear wide chromatin compaction in the presence of cellular autofluorescence [4]. Here we share FLIM data recording histone FRET in live cells co-expressing H2B-eGFP and H2B-mCherry. The data was acquired in the frequency domain [5] and processed by the phasor approach to lifetime analysis [6]. The data can be valuable to researchers interested in using the histone FRET assay since it highlights the impact of cellular autofluorescence and acceptor-donor ratio on quantifying chromatin compaction. The data is related to the research article “Phasor histone FLIM-FRET microscopy quantifies spatiotemporal rearrangement of chromatin architecture during the DNA damage response” [4].
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Affiliation(s)
- Zhen Liang
- School of Physics, University of Melbourne, Australia.,Department of Biochemistry and Molecular Biology, Bio21 Institute, University of Melbourne, Australia
| | - Jieqiong Lou
- School of Physics, University of Melbourne, Australia.,Department of Biochemistry and Molecular Biology, Bio21 Institute, University of Melbourne, Australia
| | - Lorenzo Scipioni
- Department of Biomedical Engineering, Laboratory for Fluorescence Dynamics, University of California, Irvine, United States
| | - Enrico Gratton
- Department of Biomedical Engineering, Laboratory for Fluorescence Dynamics, University of California, Irvine, United States
| | - Elizabeth Hinde
- School of Physics, University of Melbourne, Australia.,Department of Biochemistry and Molecular Biology, Bio21 Institute, University of Melbourne, Australia
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15
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Dobrinskikh E, Al-Juboori SI, Oria M, Reisz JA, Zheng C, Peiro JL, Marwan AI. Heterogeneous Response in Rabbit Fetal Diaphragmatic Hernia Lungs After Tracheal Occlusion. J Surg Res 2020; 250:23-38. [PMID: 32014698 DOI: 10.1016/j.jss.2019.12.025] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2019] [Revised: 11/10/2019] [Accepted: 12/11/2019] [Indexed: 12/20/2022]
Abstract
BACKGROUND Fetal tracheal occlusion (TO) is an experimental therapeutic approach to stimulate lung growth in the most severe congenital diaphragmatic hernia (CDH) cases. We have previously demonstrated a heterogeneous response of normal fetal rabbit lungs after TO with the appearance of at least two distinct zones. The aim of this study was to examine the fetal lung response after TO in a left CDH fetal rabbit model. METHODS Fetal rabbits at 25 d gestation underwent surgical creation of CDH followed by TO at 27 d and harvest on day 30. Morphometric analysis, global metabolomics, and fluorescence lifetime imaging microscopy (FLIM) were performed to evaluate structural and metabolic changes in control, CDH, and CDH + TO lungs. RESULTS Right and left lungs were different at the baseline and had a heterogeneous pulmonary growth response in CDH and after TO. The relative percent growth of the right lungs in CDH + TO was higher than the left lungs. Morphometric analyses revealed heterogeneous tissue-to-airspace ratios, in addition to size and number of airspaces within and between the lungs in the different groups. Global metabolomics demonstrated a slower rate of metabolism in the CDH group with the left lungs being less metabolically active. TO stimulated metabolic activity in both lungs to different degrees. FLIM analysis demonstrated local heterogeneity in glycolysis, oxidative phosphorylation (OXPHOS), and FLIM "lipid-surfactant" signal within and between the right and left lungs in all groups. CONCLUSIONS We demonstrate that TO leads to a heterogeneous morphologic and metabolic response within and between the right and left lungs in a left CDH rabbit model.
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16
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Dobrinskikh E, Al-Juboori SI, Shabeka U, Reisz JA, Zheng C, Marwan AI. Heterogeneous Pulmonary Response After Tracheal Occlusion: Clues to Fetal Lung Growth. J Surg Res 2019; 239:242-252. [PMID: 30856517 DOI: 10.1016/j.jss.2019.02.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2018] [Revised: 01/15/2019] [Accepted: 02/06/2019] [Indexed: 12/27/2022]
Abstract
BACKGROUND Understanding inconsistent clinical outcomes in infants with severe congenital diaphragmatic hernia (CDH) after tracheal occlusion (TO) is a crucial step for advancing neonatal care. The objective of this study is to explore the heterogeneous airspace morphometry and the metabolic landscape changes in fetal lungs after TO. METHODS Fetal lungs on days 1 and 4 after TO were examined using mass spectrometry-based metabolomics, fluorescence lifetime imaging microscopy (FLIM), the number of airspaces, and tissue-to-airspace ratio (TAR). RESULTS Two morphometric areas were identified in TO lungs compared with controls (more small airspaces at day 1 and a higher number of enlarged airspaces at day 4). Global metabolomics analysis revealed a significant upregulation of glycolysis and a suppression of the tricarboxylic acid cycle in day 4 TO lungs compared with day 1 TO lungs. In addition, there was a significant increase in polyamines involved in cell growth and proliferation. Locally, FLIM analysis on day 1 TO lungs demonstrated two types of heterogeneous zones-similar to control and with increased oxidative phosphorylation. FLIM on day 4 TO lungs demonstrated appearance of zones with enlarged airspaces and a metabolic shift toward glycolysis, accompanied by a decrease in the FLIM "lipid-surfactant" signal. CONCLUSIONS In normal fetal lungs, we report a novel temporal pattern of varied morphometric and metabolic changes. Initially, there is formation of zones with small airspaces, followed by airspace enlargement over time. Metabolically day 1 TO lungs have zones with increased oxidative phosphorylation, whereas day 4 TO lungs have a shift toward glycolysis in the enlarged airspaces. Based on our observations, we speculate that the "best responders" to tracheal occlusion should have bigger lungs with small airspaces and normal surfactant production.
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Affiliation(s)
- Evgenia Dobrinskikh
- Department of Medicine, University of Colorado School of Medicine, Aurora, Colorado
| | - Saif I Al-Juboori
- Division of Pediatric Surgery, Department of Surgery, University of Colorado School of Medicine, Aurora, Colorado
| | - Uladzimir Shabeka
- Division of Pediatric Surgery, Department of Surgery, University of Colorado School of Medicine, Aurora, Colorado
| | - Julie A Reisz
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, Colorado
| | - Connie Zheng
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, Colorado
| | - Ahmed I Marwan
- Division of Pediatric Surgery, Department of Surgery, University of Colorado School of Medicine, Aurora, Colorado.
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17
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Miura Y. Two-Photon Microscopy (TPM) and Fluorescence Lifetime Imaging Microscopy (FLIM) of Retinal Pigment Epithelium (RPE) of Mice In Vivo. Methods Mol Biol 2019; 1753:73-88. [PMID: 29564782 DOI: 10.1007/978-1-4939-7720-8_5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Retinal pigment epithelium (RPE), a monolayer of epithelial cells located between the neural retina and the choroid, plays a significant role in the maintenance of retinal function. Its in vivo imaging is still technically challenging in human eye. With the mouse eye, there is a possibility to look into the RPE through the sclera using two-photon microscopy (TPM). TPM is a two photon-excited nonlinear fluorescence microscopy that enables the observation of deep tissues up to several hundred micrometers. Since the simultaneous absorption of two photons occurs only at the focal plane, spatial resolution of the TPM is quite high, such that pinhole as used in a confocal microscope is not necessary. TPM enables observation of autofluorescence at the cellular level, and thus may provide new insights into the fluorescent molecules in/around RPE cells.The combination of TPM with fluorescence lifetime imaging microscopy (FLIM) may expand the breadth of information about cells and tissues. Fluorescence lifetime is a fluorophore-specific property, which is independent of fluorescence intensity and changes with the alteration of molecular environment. FLIM may have therefore the potentials to distinguish different fluorophores and to indicate the change in the environment of a fluorophore. Some energy metabolisms-related intracellular fluorophores, such as NADH (nicotinamide adenine dinucleotide) and FAD (flavin adenine dinucleotide), show characteristic fluorescence lifetimes that shift under different molecular environments, and thus their fluorescence lifetime have been used to indicate cell energy metabolic states. These nonlabeling imaging methods offer us the opportunity to engage in the study of the RPE in vivo as well as in vitro both in morphological as well as metabolic aspects.
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Affiliation(s)
- Yoko Miura
- Institute of Biomedical Optics, University of Lübeck, Lübeck, Germany. .,Department of Ophthalmology, University of Lübeck, Lübeck, Germany.
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18
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Abstract
The Bcl-2 proteins control cell death via interchanging interactions within the Bcl-2 family. Fluorescence lifetime imaging microscopy (FLIM) is used to detect Förster resonance energy transfer (FRET) between two fluorescent-fusion proteins in live cells. FLIM-FRET has been used to detect specific interactions and their disruption, for Bcl-2 family proteins. To date, this has been possible only in low throughput, due to the time required for serial data acquisition. We developed an automated optical system with eight parallel detectors for rapid and efficient data collection. Here we describe how to use this system for FLIM-FRET imaging of Bcl-2 family protein interactions in a 384-well plate format.
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Affiliation(s)
- Elizabeth J Osterlund
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada.,Sunnybrook Research Institute, Toronto, ON, Canada
| | - Nehad Hirmiz
- Sunnybrook Research Institute, Toronto, ON, Canada.,School of Biomedical Engineering, McMaster University, Hamilton, ON, Canada
| | | | - David W Andrews
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada. .,Sunnybrook Research Institute, Toronto, ON, Canada.
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19
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Abstract
Single-cell analysis is of critical importance in revealing population heterogeneity, identifying minority sub-populations of interest, as well as discovering unique characteristics of individual cells. Microfluidic platforms work at the scale comparable to cell diameter and is suitable for single-cell manipulation. Here we present a microfluidic trapping array which is able to rapidly and deterministically trap single-cells in highly-packed microwells. This chapter first describes the design and fabrication protocols of the trapping array, and then presents its two representative applications: single-cell mRNA probing when integrated with a dielectrophoretic nanotweezer (DENT), and live-cell real-time imaging when combined with fluorescence lifetime imaging microscopy (FLIM). As the single-cell trapping efficiency is determined by the channel design instead of the flow rate, this trapping array can be coupled with different microfluidic sample processing units with different flow rates for various single-cell analyses.
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Affiliation(s)
- Xuan Li
- Department of Biomedical Engineering, University of California, Irvine, CA, United States
| | - Abraham P Lee
- Department of Biomedical Engineering, University of California, Irvine, CA, United States; Department of Mechanical & Aerospace Engineering, University of California, Irvine, CA, United States.
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20
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Vieira CO, Grice JE, Roberts MS, Haridass IN, Duque MD, Lopes PS, Leite-Silva VR, Martins TS. ZnO:SBA-15 Nanocomposites for Potential Use in Sunscreen: Preparation, Properties, Human Skin Penetration and Toxicity. Skin Pharmacol Physiol 2018; 32:32-42. [PMID: 30380537 DOI: 10.1159/000491758] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Accepted: 07/02/2018] [Indexed: 11/19/2022]
Abstract
AIM We evaluated the effects of the incorporation of zinc oxide (ZnO) nanoparticles in a mesoporous matrix, aiming to improve the textural, structural and morphological properties and verify their safety so that they can be applied in sunscreen cosmetics. MATERIALS AND METHODS ZnO nano-particles were incorporated into an ordered mesoporous silica matrix known as Santa Barbara Amorphous-15 (SBA-15), using post-synthesis methodology. The resulting nanocomposites were characterized using X-ray diffraction, small angle X-ray scattering, N2 adsorption-desorption isotherms, Fourier transform infrared spectroscopy, scanning electron microscopy and predicted in vitro sun protector factor (SPF) estimation. Effectiveness and safety were evaluated by antimicrobial activity, in vitro cell toxicity and non-invasive multi-photon tomography with fluorescence lifetime imaging. RESULTS The structure of the nanocomposites was similar to that of SBA-15, with little perturbation caused by ZnO incorporation. Nanocomposites had an increased in vitro SPF, reduced cytotoxic activity and favourable antimicrobial properties compared to ZnO. ZnO:SBA-15 nanocomposites exhibited no measurable toxicity when applied to human skin in vivo. CONCLUSION Due to their suitable physicochemical properties and improved safety compared to bare ZnO nanoparticles, the ZnO:SBA-15 nanocomposites show promise for use in cosmetic applications.
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Affiliation(s)
- Camila O Vieira
- Instituto de Ciências Ambientais, Químicas e Farmacêuticas, Universidade Federal de São Paulo, UNIFESP, Diadema, Brazil
| | - Jeffrey E Grice
- Therapeutics Research Centre, University of Queensland Diamantina Institute, Translational Research Institute, Brisbane, Queensland, Australia
| | - Michael S Roberts
- Therapeutics Research Centre, University of Queensland Diamantina Institute, Translational Research Institute, Brisbane, Queensland, Australia.,School of Medical and Pharmaceutical Sciences, University of South Australia, Adelaide, South Australia, Australia
| | - Isha N Haridass
- Therapeutics Research Centre, University of Queensland Diamantina Institute, Translational Research Institute, Brisbane, Queensland, Australia
| | - Marcelo Dutra Duque
- Instituto de Ciências Ambientais, Químicas e Farmacêuticas, Universidade Federal de São Paulo, UNIFESP, Diadema, Brazil
| | - Patrícia S Lopes
- Instituto de Ciências Ambientais, Químicas e Farmacêuticas, Universidade Federal de São Paulo, UNIFESP, Diadema, Brazil
| | - Vânia R Leite-Silva
- Instituto de Ciências Ambientais, Químicas e Farmacêuticas, Universidade Federal de São Paulo, UNIFESP, Diadema, .,Therapeutics Research Centre, University of Queensland Diamantina Institute, Translational Research Institute, Brisbane, Queensland,
| | - Tereza S Martins
- Instituto de Ciências Ambientais, Químicas e Farmacêuticas, Universidade Federal de São Paulo, UNIFESP, Diadema, Brazil
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21
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Maji D, Lu J, Sarder P, Schmieder AH, Cui G, Yang X, Pan D, Lew MD, Achilefu S, Lanza GM. Cellular Trafficking of Sn-2 Phosphatidylcholine Prodrugs Studied with Fluorescence Lifetime Imaging and Super-resolution Microscopy. Precis Nanomed 2018; 1:128-145. [PMID: 31249994 PMCID: PMC6597004 DOI: 10.33218/prnano1(2).180724.1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
While the in vivo efficacy of Sn-2 phosphatidylcholine prodrugs incorporated into targeted, non-pegylated lipid-encapsulated nanoparticles was demonstrated in prior preclinical studies, the microscopic details of cell prodrug internalization and trafficking events are unknown. Classic fluorescence microscopy, fluorescence lifetime imaging microscopy, and single-molecule super-resolution microscopy were used to investigate the cellular handling of doxorubicin-prodrug and AlexaFluor™-488-prodrug. Sn-2 phosphatidylcholine prodrugs delivered by hemifusion of nanoparticle and cell phospholipid membranes functioned as phosphatidylcholine mimics, circumventing the challenges of endosome sequestration and release. Phosphatidylcholine prodrugs in the outer cell membrane leaflet translocated to the inner membrane leaflet by ATP-dependent and ATP-independent mechanisms and distributed broadly within the cytosolic membranes over the next 12 h. A portion of the phosphatidylcholine prodrug populated vesicle membranes trafficked to the perinuclear Golgi/ER region, where the drug was enzymatically liberated and activated. Native doxorubicin entered the cells, passed rapidly to the nucleus, and bound to dsDNA, whereas DOX was first enzymatically liberated from DOX-prodrug within the cytosol, particularly in the perinuclear region, before binding nuclear dsDNA. Much of DOX-prodrug was initially retained within intracellular membranes. In vitro anti-proliferation effectiveness of the two drug delivery approaches was equivalent at 48 h, suggesting that residual intracellular DOX-prodrug may constitute a slow-release drug reservoir that enhances effectiveness. We have demonstrated that Sn-2 phosphatidylcholine prodrugs function as phosphatidylcholine mimics following reported pathways of phosphatidylcholine distribution and metabolism. Drug complexed to the Sn-2 fatty acid is enzymatically liberated and reactivated over many hours, which may enhance efficacy overtime.
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Affiliation(s)
- Dolonchampa Maji
- Optical Radiology Lab, Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA.,Department of Biomedical Engineering, Washington University in St. Louis, MO 63130, USA
| | - Jin Lu
- Department of Electrical and Systems Engineering, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Pinaki Sarder
- Department of Pathology and Anatomical Sciences, Jacobs School of Medicine & Biomedical Sciences, University of Buffalo, Buffalo, NY 14203
| | - Anne H Schmieder
- Division of Cardiology, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Grace Cui
- Division of Cardiology, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Xiaoxia Yang
- Division of Cardiology, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Dipanjan Pan
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Champaign, IL, USA
| | - Matthew D Lew
- Department of Electrical and Systems Engineering, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Samuel Achilefu
- Optical Radiology Lab, Department of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA.,Department of Biomedical Engineering, Washington University in St. Louis, MO 63130, USA
| | - Gregory M Lanza
- Department of Biomedical Engineering, Washington University in St. Louis, MO 63130, USA.,Division of Cardiology, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
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22
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Suarasan S, Licarete E, Astilean S, Craciun AM. Probing cellular uptake and tracking of differently shaped gelatin-coated gold nanoparticles inside of ovarian cancer cells by two-photon excited photoluminescence analyzed by fluorescence lifetime imaging (FLIM). Colloids Surf B Biointerfaces 2018; 166:135-143. [PMID: 29558704 DOI: 10.1016/j.colsurfb.2018.03.016] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Revised: 02/26/2018] [Accepted: 03/13/2018] [Indexed: 12/18/2022]
Abstract
Nowadays, the non-linear optical effect of two-photon excited (TPE) fluorescence has recently grown in interest in recent years over other optical imaging method, due to improved 3D spatial resolution, deep penetrability and less photodamage of living organism owing to the excitation in near-infrared region (NIR). In parallel, gold nanoparticles (AuNPs) have gain considerable attention for NIR TPE bio-imaging applications due to their appealing ability to generate strong intrinsic photoluminescence (PL). Here, we demonstrate the capability of differently shaped gelatin-coated AuNPs to perform as reliable label-free contrast agents for the non-invasive NIR imaging of NIH:OVCAR-3 ovary cancer cells via TPE Fluorescence Lifetime Imaging Microscopy (FLIM). Examination of the spectroscopic profile of the intrinsic signals exhibited by AuNPs inside cells confirm the plasmonic nature of the emitted PL, while the evaluation of time-dependent profile of the TPE PL signal under continuous irradiation indicates the photo-stability of the signal revealing simultaneously a photo-blinking behavior. Finally, we assess the dependence of the TPE PL signal on laser excitation power and wavelength in view of contributing to a better understanding of plasmonic TPE PL in biological media towards the improvement of TPE FLIM imaging applications based on AuNPs.
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Affiliation(s)
- Sorina Suarasan
- Nanobiophotonics and Laser Microspectroscopy Center, Interdisciplinary Research Institute in Bio-Nano-Sciences, Babes-Bolyai University, T. Laurian 42, 400271, Cluj-Napoca, Romania
| | - Emilia Licarete
- Molecular Biology Center, Interdisciplinary Research Institute in Bio-Nano-Sciences, Babes-Bolyai University, T. Laurian 42, 400271, Cluj-Napoca, Romania
| | - Simion Astilean
- Nanobiophotonics and Laser Microspectroscopy Center, Interdisciplinary Research Institute in Bio-Nano-Sciences, Babes-Bolyai University, T. Laurian 42, 400271, Cluj-Napoca, Romania; Biomolecular Physics Department, Faculty of Physics, Babes-Bolyai University, M. Kogalniceanu 1, 400084, Cluj-Napoca, Romania
| | - Ana-Maria Craciun
- Nanobiophotonics and Laser Microspectroscopy Center, Interdisciplinary Research Institute in Bio-Nano-Sciences, Babes-Bolyai University, T. Laurian 42, 400271, Cluj-Napoca, Romania.
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23
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Edlich A, Volz P, Brodwolf R, Unbehauen M, Mundhenk L, Gruber AD, Hedtrich S, Haag R, Alexiev U, Kleuser B. Crosstalk between core-multishell nanocarriers for cutaneous drug delivery and antigen-presenting cells of the skin. Biomaterials 2018; 162:60-70. [PMID: 29438881 DOI: 10.1016/j.biomaterials.2018.01.058] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 01/24/2018] [Accepted: 01/31/2018] [Indexed: 01/15/2023]
Abstract
Owing their unique chemical and physical properties core-multishell (CMS) nanocarriers are thought to underlie their exploitable biomedical use for a topical treatment of skin diseases. This highlights the need to consider not only the efficacy of CMS nanocarriers but also the potentially unpredictable and adverse consequences of their exposure thereto. As CMS nanocarriers are able to penetrate into viable layers of normal and stripped human skin ex vivo as well as in in vitro skin disease models the understanding of nanoparticle crosstalk with components of the immune system requires thorough investigation. Our studies highlight the biocompatible properties of CMS nanocarriers on Langerhans cells of the skin as they did neither induce cytotoxicity and genotoxicity nor cause reactive oxygen species (ROS) or an immunological response. Nevertheless, CMS nanocarriers were efficiently taken up by Langerhans cells via divergent endocytic pathways. Bioimaging of CMS nanocarriers by fluorescence lifetime imaging microscopy (FLIM) and flow cytometry indicated not only a localization within the lysosomes but also an energy-dependent exocytosis of unmodified CMS nanocarriers into the extracellular environment.
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Affiliation(s)
- Alexander Edlich
- Institute of Nutritional Science, University of Potsdam, Potsdam, Germany
| | - Pierre Volz
- Institute of Experimental Physics, Freie Universität Berlin, Berlin, Germany
| | - Robert Brodwolf
- Institute of Experimental Physics, Freie Universität Berlin, Berlin, Germany
| | - Michael Unbehauen
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany
| | - Lars Mundhenk
- Institute of Veterinary Pathology, Freie Universität Berlin, Berlin, Germany
| | - Achim D Gruber
- Institute of Veterinary Pathology, Freie Universität Berlin, Berlin, Germany
| | - Sarah Hedtrich
- Institute of Pharmacy, Freie Universität Berlin, Berlin, Germany
| | - Rainer Haag
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany
| | - Ulrike Alexiev
- Institute of Experimental Physics, Freie Universität Berlin, Berlin, Germany.
| | - Burkhard Kleuser
- Institute of Nutritional Science, University of Potsdam, Potsdam, Germany.
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Schützhold V, Fandrey J, Prost-Fingerle K. Fluorescence Lifetime Imaging Microscopy (FLIM) as a Tool to Investigate Hypoxia-Induced Protein-Protein Interaction in Living Cells. Methods Mol Biol 2018; 1742:45-53. [PMID: 29330789 DOI: 10.1007/978-1-4939-7665-2_5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Fluorescence resonance energy transfer (FRET) is widely used as a method to investigate protein-protein interactions in living cells. A FRET pair donor fluorophore in close proximity to an appropriate acceptor fluorophore transfers emission energy to the acceptor, resulting in a shorter lifetime of the donor fluorescence. When the respective FRET donor and acceptor are fused with two proteins of interest, a reduction in donor lifetime, as detected by fluorescence lifetime imaging microscopy (FLIM), can be taken as proof of close proximity between the fluorophores and therefore interaction between the proteins of interest. Here, we describe the usage of time-domain FLIM-FRET in hypoxia-related research when we record the interaction of the hypoxia-inducible factor-1 (HIF-1) subunits HIF-1α and HIF-1β in living cells in a temperature- and CO2-controlled environment under the microscope.
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Affiliation(s)
- Vera Schützhold
- Institute of Physiology, University of Duisburg-Essen, Essen, Germany
| | - Joachim Fandrey
- Institute of Physiology, University of Duisburg-Essen, Essen, Germany.
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Abstract
Sequential enzymes in biosynthetic pathways are organized in metabolons. It is challenging to provide experimental evidence for the existence of metabolons as biosynthetic pathways are composed of highly dynamic protein-protein interactions. Many different methods are being applied, each with strengths and weaknesses. We will present and evaluate several techniques that have been applied in providing evidence for the orchestration of the biosynthetic pathways of cyanogenic glucosides and glucosinolates in metabolons. These evolutionarily related pathways have ER-localized cytochromes P450 that are proposed to function as anchoring site for assembly of the enzymes into metabolons. Additionally, we have included commonly used techniques, even though they have not been used (yet) on these two pathways. In the review, special attention will be given to less-exploited fluorescence-based methods such as FCS and FLIM. Ultimately, understanding the orchestration of biosynthetic pathways may contribute to successful engineering in heterologous hosts.
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Affiliation(s)
- Jean-Etienne Bassard
- Plant Biochemistry Laboratory, Center for Synthetic Biology, VILLUM Research Center “Plant Plasticity”, Department of Plant and Environmental Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Barbara Ann Halkier
- DynaMo Center, Department of Plant and Environmental Sciences, University of Copenhagen, Copenhagen, Denmark
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Radbruch M, Pischon H, Ostrowski A, Volz P, Brodwolf R, Neumann F, Unbehauen M, Kleuser B, Haag R, Ma N, Alexiev U, Mundhenk L, Gruber AD. Dendritic Core-Multishell Nanocarriers in Murine Models of Healthy and Atopic Skin. Nanoscale Res Lett 2017; 12:64. [PMID: 28116609 PMCID: PMC5256633 DOI: 10.1186/s11671-017-1835-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 12/23/2016] [Indexed: 05/22/2023]
Abstract
Dendritic hPG-amid-C18-mPEG core-multishell nanocarriers (CMS) represent a novel class of unimolecular micelles that hold great potential as drug transporters, e.g., to facilitate topical therapy in skin diseases. Atopic dermatitis is among the most common inflammatory skin disorders with complex barrier alterations which may affect the efficacy of topical treatment.Here, we tested the penetration behavior and identified target structures of unloaded CMS after topical administration in healthy mice and in mice with oxazolone-induced atopic dermatitis. We further examined whole body distribution and possible systemic side effects after simulating high dosage dermal penetration by subcutaneous injection.Following topical administration, CMS accumulated in the stratum corneum without penetration into deeper viable epidermal layers. The same was observed in atopic dermatitis mice, indicating that barrier alterations in atopic dermatitis had no influence on the penetration of CMS. Following subcutaneous injection, CMS were deposited in the regional lymph nodes as well as in liver, spleen, lung, and kidney. However, in vitro toxicity tests, clinical data, and morphometry-assisted histopathological analyses yielded no evidence of any toxic or otherwise adverse local or systemic effects of CMS, nor did they affect the severity or course of atopic dermatitis.Taken together, CMS accumulate in the stratum corneum in both healthy and inflammatory skin and appear to be highly biocompatible in the mouse even under conditions of atopic dermatitis and thus could potentially serve to create a depot for anti-inflammatory drugs in the skin.
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Affiliation(s)
- Moritz Radbruch
- Institute of Veterinary Pathology, Freie Universität Berlin, Robert-von-Ostertag-Str. 15, 14163 Berlin, Germany
| | - Hannah Pischon
- Institute of Veterinary Pathology, Freie Universität Berlin, Robert-von-Ostertag-Str. 15, 14163 Berlin, Germany
| | - Anja Ostrowski
- Institute of Veterinary Pathology, Freie Universität Berlin, Robert-von-Ostertag-Str. 15, 14163 Berlin, Germany
| | - Pierre Volz
- Institute of Experimental Physics, Department of Physics, Freie Universität Berlin, Berlin, Germany
| | - Robert Brodwolf
- Institute of Experimental Physics, Department of Physics, Freie Universität Berlin, Berlin, Germany
| | - Falko Neumann
- Institute of Biomaterial Science and Berlin-Brandenburg Centre for Regenerative Therapies, Helmholtz-Zentrum Geesthacht, Teltow, Germany
| | - Michael Unbehauen
- Institute of Chemistry and Biochemistry, Organic Chemistry, Freie Universität Berlin, Berlin, Germany
| | - Burkhard Kleuser
- Institute of Nutritional Science, University of Potsdam, Nuthetal, Germany
| | - Rainer Haag
- Institute of Chemistry and Biochemistry, Organic Chemistry, Freie Universität Berlin, Berlin, Germany
| | - Nan Ma
- Institute of Biomaterial Science and Berlin-Brandenburg Centre for Regenerative Therapies, Helmholtz-Zentrum Geesthacht, Teltow, Germany
| | - Ulrike Alexiev
- Institute of Experimental Physics, Department of Physics, Freie Universität Berlin, Berlin, Germany
| | - Lars Mundhenk
- Institute of Veterinary Pathology, Freie Universität Berlin, Robert-von-Ostertag-Str. 15, 14163 Berlin, Germany
| | - Achim D. Gruber
- Institute of Veterinary Pathology, Freie Universität Berlin, Robert-von-Ostertag-Str. 15, 14163 Berlin, Germany
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Abstract
Understanding plant cell wall cross-linking chemistry and polymeric architecture is key to the efficient utilization of biomass in all prospects from rational genetic modification to downstream chemical and biological conversion to produce fuels and value chemicals. In fact, the bulk properties of cell wall recalcitrance are collectively determined by its chemical features over a wide range of length scales from tissue, cellular to polymeric architectures. Microscopic visualization of cell walls from the nanometer to the micrometer scale offers an in situ approach to study their chemical functionality considering its spatial and chemical complexity, particularly the capabilities of characterizing biomass non-destructively and in real-time during conversion processes. Microscopic characterization has revealed heterogeneity in the distribution of chemical features, which would otherwise be hidden in bulk analysis. Key microscopic features include cell wall type, wall layering, and wall composition-especially cellulose and lignin distributions. Microscopic tools, such as atomic force microscopy, stimulated Raman scattering microscopy, and fluorescence microscopy, have been applied to investigations of cell wall structure and chemistry from the native wall to wall treated by thermal chemical pretreatment and enzymatic hydrolysis. While advancing our current understanding of plant cell wall recalcitrance and deconstruction, microscopic tools with improved spatial resolution will steadily enhance our fundamental understanding of cell wall function.
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Affiliation(s)
- Yining Zeng
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401 USA
- BioEnergy Science Center (BESC), Oak Ridge National Laboratory, PO Box 2008 MS6341, Oak Ridge, TN 37831 USA
| | - Michael E. Himmel
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401 USA
- BioEnergy Science Center (BESC), Oak Ridge National Laboratory, PO Box 2008 MS6341, Oak Ridge, TN 37831 USA
| | - Shi-You Ding
- Department of Plant Biology, Michigan State University, East Lansing, MI 48824 USA
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Abstract
Phospholipids are important signaling molecules that regulate cell proliferation, death, migration, and metabolism. Many phospholipid signaling cascades are altered in breast cancer. To understand the functions of phospholipid signaling molecules, genetically encoded phospholipid biosensors have been developed to monitor their spatiotemporal dynamics. Compared to other phospholipids, much less is known about the subcellular production and cellular functions of phosphatidic acid (PA), partially due to the lack of a specific and sensitive PA biosensor in the past. This chapter describes the use of a newly developed PA biosensor, PASS, in two applications: regular fluorescent microscopy and fluorescence lifetime imaging microscopy-Förster/fluorescence resonance energy transfer (FLIM-FRET). These protocols can be also used with other phospholipid biosensors.
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Palusińska-Szysz M, Zdybicka-Barabas A, Reszczyńska E, Luchowski R, Kania M, Gisch N, Waldow F, Mak P, Danikiewicz W, Gruszecki WI, Cytryńska M. The lipid composition of Legionella dumoffii membrane modulates the interaction with Galleria mellonella apolipophorin III. Biochim Biophys Acta Mol Cell Biol Lipids 2016; 1861:617-29. [PMID: 27094351 DOI: 10.1016/j.bbalip.2016.04.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Revised: 04/11/2016] [Accepted: 04/15/2016] [Indexed: 11/26/2022]
Abstract
Apolipophorin III (apoLp-III), an insect homologue of human apolipoprotein E (apoE), is a widely used model protein in studies on protein-lipid interactions, and anti-Legionella activity of Galleria mellonella apoLp-III has been documented. Interestingly, exogenous choline-cultured Legionella dumoffii cells are considerably more susceptible to apoLp-III than non-supplemented bacteria. In order to explain these differences, we performed, for the first time, a detailed analysis of L. dumoffii lipids and a comparative lipidomic analysis of membranes of bacteria grown without and in the presence of exogenous choline. (31)P NMR analysis of L. dumoffii phospholipids (PLs) revealed a considerable increase in the phosphatidylcholine (PC) content in bacteria cultured on choline medium and a decrease in the phosphatidylethanolamine (PE) content in approximately the same range. The interactions of G. mellonella apoLp-III with lipid bilayer membranes prepared from PLs extracted from non- and choline-supplemented L. dumoffii cells were examined in detail by means of attenuated total reflection- and linear dichroism-Fourier transform infrared spectroscopy. Furthermore, the kinetics of apoLp-III binding to liposomes formed from L. dumoffii PLs was analysed by fluorescence correlation spectroscopy and fluorescence lifetime imaging microscopy using fluorescently labelled G. mellonella apoLp-III. Our results indicated enhanced binding of apoLp-III to and deeper penetration into lipid membranes formed from PLs extracted from the choline-supplemented bacteria, i.e. characterized by an increased PC/PE ratio. This could explain, at least in part, the higher susceptibility of choline-cultured L. dumoffii to G. mellonella apoLp-III.
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Affiliation(s)
- Marta Palusińska-Szysz
- Department of Genetics and Microbiology, Institute of Microbiology and Biotechnology, Maria Curie-Sklodowska University, Akademicka St. 19, 20-033 Lublin, Poland.
| | - Agnieszka Zdybicka-Barabas
- Department of Immunobiology, Institute of Biology and Biochemistry, Maria Curie-Sklodowska University, Akademicka St. 19, 20-033 Lublin, Poland.
| | - Emilia Reszczyńska
- Department of Biophysics, Institute of Physics, Maria Curie-Sklodowska University, Maria Curie-Sklodowska Square 1, 20-031 Lublin, Poland; Department of Biophysics, Institute of Biology and Biochemistry, Maria Curie-Sklodowska University, Akademicka St. 19, 20-033 Lublin, Poland.
| | - Rafał Luchowski
- Department of Biophysics, Institute of Physics, Maria Curie-Sklodowska University, Maria Curie-Sklodowska Square 1, 20-031 Lublin, Poland.
| | - Magdalena Kania
- Mass Spectrometry Group, Institute of Organic Chemistry Polish Academy of Sciences, Kasprzaka 44/52 St., 01-224 Warsaw, Poland.
| | - Nicolas Gisch
- Division of Bioanalytical Chemistry, Research Center Borstel, Leibniz-Center for Medicine and Biosciences, Parkallee 1-40, 23845 Borstel, Germany.
| | - Franziska Waldow
- Division of Bioanalytical Chemistry, Research Center Borstel, Leibniz-Center for Medicine and Biosciences, Parkallee 1-40, 23845 Borstel, Germany.
| | - Paweł Mak
- Department of Analytical Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7 St., 30-387 Krakow; Malopolska Centre of Biotechnology, Gronostajowa 7A St., 30-387 Krakow, Poland.
| | - Witold Danikiewicz
- Mass Spectrometry Group, Institute of Organic Chemistry Polish Academy of Sciences, Kasprzaka 44/52 St., 01-224 Warsaw, Poland.
| | - Wiesław I Gruszecki
- Department of Biophysics, Institute of Physics, Maria Curie-Sklodowska University, Maria Curie-Sklodowska Square 1, 20-031 Lublin, Poland.
| | - Małgorzata Cytryńska
- Department of Immunobiology, Institute of Biology and Biochemistry, Maria Curie-Sklodowska University, Akademicka St. 19, 20-033 Lublin, Poland.
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30
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Söhnel AC, Kohl W, Gregor I, Enderlein J, Rieger B, Busch KB. Probing of protein localization and shuttling in mitochondrial microcompartments by FLIM with sub-diffraction resolution. Biochim Biophys Acta 2016; 1857:1290-9. [PMID: 27016377 DOI: 10.1016/j.bbabio.2016.03.021] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Revised: 03/17/2016] [Accepted: 03/18/2016] [Indexed: 12/31/2022]
Abstract
The cell is metabolically highly compartmentalized. Especially, mitochondria host many vital reactions in their different microcompartments. However, due to their small size, these microcompartments are not accessible by conventional microscopy. Here, we demonstrate that time-correlated single-photon counting (TCSPC) fluorescence lifetime-imaging microscopy (FLIM) classifies not only mitochondria, but different microcompartments inside mitochondria. Sensor proteins in the matrix had a different lifetime than probes at membrane proteins. Localization in the outer and inner mitochondrial membrane could be distinguished by significant differences in the lifetime. The method was sensitive enough to monitor shifts in protein location within mitochondrial microcompartments. Macromolecular crowding induced by changes in the protein content significantly affected the lifetime, while oxidizing conditions or physiological pH changes had only marginal effects. We suggest that FLIM is a versatile and completive method to monitor spatiotemporal events in mitochondria. The sensitivity in the time domain allows for gaining substantial information about sub-mitochondrial localization overcoming diffraction limitation. This article is part of a Special Issue entitled 'EBEC 2016: 19th European Bioenergetics Conference, Riva del Garda, Italy, July 2-6, 2016', edited by Prof. Paolo Bernardi.
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31
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Nozue S, Mukuno A, Tsuda Y, Shiina T, Terazima M, Kumazaki S. Characterization of thylakoid membrane in a heterocystous cyanobacterium and green alga with dual-detector fluorescence lifetime imaging microscopy with a systematic change of incident laser power. Biochim Biophys Acta 2015; 1857:46-59. [PMID: 26474523 DOI: 10.1016/j.bbabio.2015.10.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Revised: 09/29/2015] [Accepted: 10/11/2015] [Indexed: 12/01/2022]
Abstract
Fluorescence Lifetime Imaging Microscopy (FLIM) has been applied to plants, algae and cyanobacteria, in which excitation laser conditions affect the chlorophyll fluorescence lifetime due to several mechanisms. However, the dependence of FLIM data on input laser power has not been quantitatively explained by absolute excitation probabilities under actual imaging conditions. In an effort to distinguish between photosystem I and photosystem II (PSI and PSII) in microscopic images, we have obtained dependence of FLIM data on input laser power from a filamentous cyanobacterium Anabaena variabilis and single cellular green alga Parachlorella kessleri. Nitrogen-fixing cells in A. variabilis, heterocysts, are mostly visualized as cells in which short-lived fluorescence (≤0.1 ns) characteristic of PSI is predominant. The other cells in A. variabilis (vegetative cells) and P. kessleri cells show a transition in the status of PSII from an open state with the maximal charge separation rate at a weak excitation limit to a closed state in which charge separation is temporarily prohibited by previous excitation(s) at a relatively high laser power. This transition is successfully reproduced by a computer simulation with a high fidelity to the actual imaging conditions. More details in the fluorescence from heterocysts were examined to assess possible functions of PSII in the anaerobic environment inside the heterocysts for the nitrogen-fixing enzyme, nitrogenase. Photochemically active PSII:PSI ratio in heterocysts is tentatively estimated to be typically below our detection limit or at most about 5% in limited heterocysts in comparison with that in vegetative cells.
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Affiliation(s)
- Shuho Nozue
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Akira Mukuno
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Yumi Tsuda
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Takashi Shiina
- Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Sakyo-ku, Kyoto 606-8522, Japan
| | - Masahide Terazima
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Shigeichi Kumazaki
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan.
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Zeng Y, Zhao S, Wei H, Tucker MP, Himmel ME, Mosier NS, Meilan R, Ding SY. In situ micro-spectroscopic investigation of lignin in poplar cell walls pretreated by maleic acid. Biotechnol Biofuels 2015; 8:126. [PMID: 26312066 PMCID: PMC4549890 DOI: 10.1186/s13068-015-0312-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Accepted: 08/13/2015] [Indexed: 05/09/2023]
Abstract
BACKGROUND In higher plant cells, lignin provides necessary physical support for plant growth and resistance to attack by microorganisms. For the same reason, lignin is considered to be a major impediment to the process of deconstructing biomass to simple sugars by hydrolytic enzymes. The in situ variation of lignin in plant cell walls is important for better understanding of the roles lignin play in biomass recalcitrance. RESULTS A micro-spectroscopic approach combining stimulated Raman scattering microscopy and fluorescence lifetime imaging microscopy was employed to probe the physiochemical structure of lignin in poplar tracheid cell walls. Two forms of lignins were identified: loosely packed lignin, which had a long (4 ns) fluorescence lifetime and existed primarily in the secondary wall layers; and dense lignin, which had a short (0.5-1 ns) fluorescence lifetime and was present in all wall layers, including the cell corners, compound middle lamellae, and secondary wall. At low maleic acid concentration (0.025 and 0.05 M) pretreatment conditions, some of the dense lignin was modified to become more loosely packed. High acid concentration removed both dense and loosely packed lignins. These modified lignins reformed to make lignin-carbohydrate complex droplets containing either dense or loosely packed lignin (mostly from secondary walls) and were commonly observed on the cell wall surface. CONCLUSIONS We have identified dense and loosely packed lignins in plant cell walls. During maleic acid pretreatment, both dense lignin droplets and loosely packed lignin droplets were formed. Maleic acid pretreatment more effectively removes loosely packed lignin in secondary walls which increases enzyme accessibility for digestion.
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Affiliation(s)
- Yining Zeng
- />Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401 USA
| | - Shuai Zhao
- />Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401 USA
| | - Hui Wei
- />Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401 USA
| | - Melvin P. Tucker
- />National Bioenergy Center, National Renewable Energy Laboratory, Golden, CO 80401 USA
| | - Michael E. Himmel
- />Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401 USA
| | - Nathan S. Mosier
- />Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, IN 47907 USA
| | - Richard Meilan
- />Department of Forestry and Natural Resources, Purdue University, West Lafayette, IN 47907 USA
| | - Shi-You Ding
- />Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401 USA
- />Department of Plant Biology, Michigan State University, East Lansing, MI 48824 USA
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33
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Cost AL, Ringer P, Chrostek-Grashoff A, Grashoff C. How to Measure Molecular Forces in Cells: A Guide to Evaluating Genetically-Encoded FRET-Based Tension Sensors. Cell Mol Bioeng 2014; 8:96-105. [PMID: 25798203 PMCID: PMC4361753 DOI: 10.1007/s12195-014-0368-1] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Accepted: 11/21/2014] [Indexed: 12/16/2022] Open
Abstract
The ability of cells to sense and respond to mechanical forces is central to a wide range of biological processes and plays an important role in numerous pathologies. The molecular mechanisms underlying cellular mechanotransduction, however, have remained largely elusive because suitable methods to investigate subcellular force propagation were missing. Here, we review recent advances in the development of biosensors that allow molecular force measurements. We describe the underlying principle of currently available techniques and propose a strategy to systematically evaluate new Förster resonance energy transfer (FRET)-based biosensors.
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Affiliation(s)
- Anna-Lena Cost
- Group of Molecular Mechanotransduction, Max Planck Institute of Biochemistry, Am Klopferspitz 18, Martinsried, 82152 Germany
| | - Pia Ringer
- Group of Molecular Mechanotransduction, Max Planck Institute of Biochemistry, Am Klopferspitz 18, Martinsried, 82152 Germany
| | - Anna Chrostek-Grashoff
- Group of Molecular Mechanotransduction, Max Planck Institute of Biochemistry, Am Klopferspitz 18, Martinsried, 82152 Germany
| | - Carsten Grashoff
- Group of Molecular Mechanotransduction, Max Planck Institute of Biochemistry, Am Klopferspitz 18, Martinsried, 82152 Germany
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34
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Tokumasu F, Crivat G, Ackerman H, Hwang J, Wellems TE. Inward cholesterol gradient of the membrane system in P. falciparum-infected erythrocytes involves a dilution effect from parasite-produced lipids. Biol Open 2014; 3:529-41. [PMID: 24876390 PMCID: PMC4058088 DOI: 10.1242/bio.20147732] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Plasmodium falciparum (Pf) infection remodels the human erythrocyte with new membrane systems, including a modified host erythrocyte membrane (EM), a parasitophorous vacuole membrane (PVM), a tubulovesicular network (TVN), and Maurer's clefts (MC). Here we report on the relative cholesterol contents of these membranes in parasitized normal (HbAA) and hemoglobin S-containing (HbAS, HbAS) erythrocytes. Results from fluorescence lifetime imaging microscopy (FLIM) experiments with a cholesterol-sensitive fluorophore show that membrane cholesterol levels in parasitized erythrocytes (pRBC) decrease inwardly from the EM, to the MC/TVN, to the PVM, and finally to the parasite membrane (PM). Cholesterol depletion of pRBC by methyl-β-cyclodextrin treatment caused a collapse of this gradient. Lipid and cholesterol exchange data suggest that the cholesterol gradient involves a dilution effect from non-sterol lipids produced by the parasite. FLIM signals from the PVM or PM showed little or no difference between parasitized HbAA vs HbS-containing erythrocytes that differed in lipid content, suggesting that malaria parasites may regulate the cholesterol contents of the PVM and PM independently of levels in the host cell membrane. Cholesterol levels may affect raft structures and the membrane trafficking and sorting functions that support Pf survival in HbAA, HbAS and HbSS erythrocytes.
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Affiliation(s)
- Fuyuki Tokumasu
- Malaria Genetics Section, Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892-8132, USA Present address: Department of Lipidomics, Faculty of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Georgeta Crivat
- Malaria Genetics Section, Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892-8132, USA Quantum Electronics and Photonics Division, Physical Measurement Laboratory, National Institute of Standards and Technology, Boulder, CO 80305, USA
| | - Hans Ackerman
- Malaria Genetics Section, Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892-8132, USA
| | - Jeeseong Hwang
- Quantum Electronics and Photonics Division, Physical Measurement Laboratory, National Institute of Standards and Technology, Boulder, CO 80305, USA
| | - Thomas E Wellems
- Malaria Genetics Section, Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892-8132, USA
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35
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Hu D, Sarder P, Ronhovde P, Orthaus S, Achilefu S, Nussinov Z. Automatic segmentation of fluorescence lifetime microscopy images of cells using multiresolution community detection--a first study. J Microsc 2013; 253:54-64. [PMID: 24251410 DOI: 10.1111/jmi.12097] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Accepted: 10/09/2013] [Indexed: 11/30/2022]
Abstract
Inspired by a multiresolution community detection based network segmentation method, we suggest an automatic method for segmenting fluorescence lifetime (FLT) imaging microscopy (FLIM) images of cells in a first pilot investigation on two selected images. The image processing problem is framed as identifying segments with respective average FLTs against the background in FLIM images. The proposed method segments a FLIM image for a given resolution of the network defined using image pixels as the nodes and similarity between the FLTs of the pixels as the edges. In the resulting segmentation, low network resolution leads to larger segments, and high network resolution leads to smaller segments. Furthermore, using the proposed method, the mean-square error in estimating the FLT segments in a FLIM image was found to consistently decrease with increasing resolution of the corresponding network. The multiresolution community detection method appeared to perform better than a popular spectral clustering-based method in performing FLIM image segmentation. At high resolution, the spectral segmentation method introduced noisy segments in its output, and it was unable to achieve a consistent decrease in mean-square error with increasing resolution.
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Affiliation(s)
- D Hu
- Department of Physics, Washington University, St. Louis, Missouri, USA
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Sivaguru M, Eichorst JP, Durgam S, Fried GA, Stewart AA, Stewart MC. Imaging horse tendons using multimodal 2-photon microscopy. Methods 2013; 66:256-67. [PMID: 23871762 DOI: 10.1016/j.ymeth.2013.07.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Revised: 07/07/2013] [Accepted: 07/08/2013] [Indexed: 01/14/2023] Open
Abstract
Injuries and damage to tendons plague both human and equine athletes. At the site of injuries, various cells congregate to repair and re-structure the collagen. Treatments for collagen injury range from simple procedures such as icing and pharmaceutical treatments to more complex surgeries and the implantation of stem cells. Regardless of the treatment, the level of mechanical stimulation incurred by the recovering tendon is crucial. However, for a given tendon injury, it is not known precisely how much of a load should be applied for an effective recovery. Both too much and too little loading of the tendon could be detrimental during recovery. A mapping of the complex local environment imparted to any cell present at the site of a tendon injury may however, convey fundamental insights related to their decision making as a function of applied load. Therefore, fundamentally knowing how cells translate mechanical cues from their external environment into signals regulating their functions during repair is crucial to more effectively treat these types of injuries. In this paper, we studied systems of tendons with a variety of 2-photon-based imaging techniques to examine the local mechanical environment of cells in both normal and injured tendons. These tendons were chemically treated to instigate various extents of injury and in some cases, were injected with stem cells. The results related by each imaging technique distinguish with high contrast and resolution multiple morphologies of the cells' nuclei and the alignment of the collagen during injury. The incorporation of 2-photon FLIM into this study probed new features in the local environment of the nuclei that were not apparent with steady-state imaging. Overall, this paper focuses on horse tendon injury pattern and analysis with different 2-photon confocal modalities useful for wide variety of application in damaged tissues.
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Affiliation(s)
- Mayandi Sivaguru
- Institute for Genomic Biology, University of Illinois Urbana-Champaign, 1206 West Gregory Drive, Urbana, IL 61801, USA.
| | - John Paul Eichorst
- Institute for Genomic Biology, University of Illinois Urbana-Champaign, 1206 West Gregory Drive, Urbana, IL 61801, USA
| | - Sushmitha Durgam
- Veterinary Clinical Medicine, University of Illinois Urbana-Champaign, 2001 South Lincoln Avenue, Urbana, IL 61801, USA
| | - Glenn A Fried
- Institute for Genomic Biology, University of Illinois Urbana-Champaign, 1206 West Gregory Drive, Urbana, IL 61801, USA
| | - Allison A Stewart
- Veterinary Clinical Medicine, University of Illinois Urbana-Champaign, 2001 South Lincoln Avenue, Urbana, IL 61801, USA
| | - Matthew C Stewart
- Veterinary Clinical Medicine, University of Illinois Urbana-Champaign, 2001 South Lincoln Avenue, Urbana, IL 61801, USA
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Abstract
Fluorescence lifetime imaging microscopy (FLIM) is a method for measuring fluorophore lifetimes with microscopic spatial resolution, providing a useful tool for cell biologists to detect, visualize, and investigate structure and function of biological systems. In this chapter, we begin by introducing the basic theory of fluorescence lifetime, including the characteristics of fluorophore decay, followed by a discussion of factors affecting fluorescence lifetimes and the potential advantages of fluorescence lifetime as a source of image contrast. Experimental methods for creating lifetime maps, including both time- and frequency-domain experimental approaches, are then introduced. Then, FLIM data analysis methods are discussed, including rapid lifetime determination, multiexponential fitting, Laguerre polynomial fitting, and phasor plot analysis. After, data analysis methods are introduced that improve lifetime precision of FLIM maps based upon optimal virtual gating and total variation denoising. The chapter concludes by highlighting several recent FLIM applications for quantitative biological imaging, including Förster resonance energy transfer-FLIM, fluorescence correlation spectroscopy-FLIM, multispectral-FLIM, and multiphoton-FLIM.
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Affiliation(s)
- Leng-Chun Chen
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan, USA
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