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Abstract
In this series of papers on light microscopy imaging, we have covered the fundamentals of microscopy, super-resolution microscopy, and lightsheet microscopy. This last review covers multi-photon microscopy with a brief reference to intravital imaging and Brainbow labeling. Multi-photon microscopy is often referred to as two-photon microscopy. Indeed, using two-photon microscopy is by far the most common way of imaging thick tissues; however, it is theoretically possible to use a higher number of photons, and three-photon microscopy is possible. Therefore, this review is titled "multi-photon microscopy." Another term for describing multi-photon microscopy is "non-linear" microscopy because fluorescence intensity at the focal spot depends upon the average squared intensity rather than the squared average intensity; hence, non-linear optics (NLO) is an alternative name for multi-photon microscopy. It is this non-linear relationship (or third exponential power in the case of three-photon excitation) that determines the axial optical sectioning capability of multi-photon imaging. In this paper, the necessity for two-photon or multi-photon imaging is explained, and the method of optical sectioning by multi-photon microscopy is described. Advice is also given on what fluorescent markers to use and other practical aspects of imaging thick tissues. The technique of Brainbow imaging is discussed. The review concludes with a description of intravital imaging of the mouse. © 2023 Wiley Periodicals LLC.
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2
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A de novo matrix for macroscopic living materials from bacteria. Nat Commun 2022; 13:5544. [PMID: 36130968 PMCID: PMC9492681 DOI: 10.1038/s41467-022-33191-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Accepted: 09/08/2022] [Indexed: 11/08/2022] Open
Abstract
Engineered living materials (ELMs) embed living cells in a biopolymer matrix to create materials with tailored functions. While bottom-up assembly of macroscopic ELMs with a de novo matrix would offer the greatest control over material properties, we lack the ability to genetically encode a protein matrix that leads to collective self-organization. Here we report growth of ELMs from Caulobacter crescentus cells that display and secrete a self-interacting protein. This protein formed a de novo matrix and assembled cells into centimeter-scale ELMs. Discovery of design and assembly principles allowed us to tune the composition, mechanical properties, and catalytic function of these ELMs. This work provides genetic tools, design and assembly rules, and a platform for growing ELMs with control over both matrix and cellular structure and function. Engineered living materials (ELMs) embed living cells in a biopolymer matrix to create novel materials with tailored functions. In this work, the authors engineered bacteria to grow novel macroscopic materials that can be reshaped, functionalized, and used to filter contaminated water while also showing that the stiffness of these materials can be tuned through genetic changes.
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3
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Lee M, Kannan S, Muniraj G, Rosa V, Lu WF, Fuh JYH, Sriram G, Cao T. Two-Photon Fluorescence Microscopy and Applications in Angiogenesis and Related Molecular Events. TISSUE ENGINEERING PART B-REVIEWS 2021; 28:926-937. [PMID: 34541887 DOI: 10.1089/ten.teb.2021.0140] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The role of angiogenesis in health and disease have gained considerable momentum in recent years. Visualizing angiogenic patterns and associated events of surrounding vascular beds in response to therapeutic and laboratory-grade biomolecules have become a commonplace in regenerative medicine and the biosciences. To aid imaging investigations in angiogenesis, the two-photon excitation fluorescence microscopy (2PEF), or multiphoton fluorescence microscopy is increasingly utilized in scientific investigations. The 2PEF microscope confers several distinct imaging advantages over other fluorescence excitation microscopy techniques - for the observation of in-depth, three-dimensional vascularity in a variety of tissue formats, including fixed tissue specimens and in vivo vasculature in live specimens. Understanding morphological and subcellular changes that occur in cells and tissues during angiogenesis will provide insights to behavioral responses in diseased states, advance the engineering of physiologically-relevant tissue models and provide biochemical clues for the design of therapeutic strategies. We review the applicability and limitations of the 2PEF microscope on the biophysical and molecular-level signatures of angiogenesis in various tissue models. Imaging techniques and strategies for best practices in 2PEF microscopy will be reviewed.
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Affiliation(s)
- Marcus Lee
- Faculty of Dentistry, National University of Singapore, Singapore, Singapore
| | - Sathya Kannan
- Faculty of Dentistry, National University of Singapore, Singapore, Singapore
| | - Giridharan Muniraj
- Faculty of Dentistry, National University of Singapore, Singapore, Singapore
| | - Vinicius Rosa
- Faculty of Dentistry, National University of Singapore, Singapore, Singapore
| | - Wen Feng Lu
- Department of Mechanical Engineering, National University of Singapore, Singapore, Singapore
| | - Jerry Y H Fuh
- Department of Mechanical Engineering, National University of Singapore, Singapore, Singapore
| | - Gopu Sriram
- Faculty of Dentistry, National University of Singapore, Singapore, Singapore
| | - Tong Cao
- Faculty of Dentistry, National University of Singapore, Singapore, Singapore
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4
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Wong EL, Strohm A, Atlas J, Lamantia C, Majewska AK. Dynamics of microglia and dendritic spines in early adolescent cortex after developmental alcohol exposure. Dev Neurobiol 2021; 81:786-804. [PMID: 34228891 DOI: 10.1002/dneu.22843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2021] [Revised: 05/26/2021] [Accepted: 06/13/2021] [Indexed: 11/05/2022]
Abstract
Fetal alcohol spectrum disorder patients suffer from many cognitive disabilities. These include impaired auditory, visual, and tactile sensory information processing, making it more difficult for these patients to learn to navigate social scenarios. Rodent studies have shown that alcohol exposure during the brain growth spurt (BGS) can lead to acute neuronal apoptosis and an immunological response by microglia in the somatosensory cortex. Since microglia have critical physiological functions, including the support of excitatory synapse remodeling via interactions with dendritic spines, we sought to understand whether BGS alcohol exposure has long-term effects on microglial or dendritic spine dynamics. Using in vivo two-photon microscopy in 4-5 week old mice, we evaluated microglial functions such as process motility, the response to tissue injury, and the dynamics of physical interactions between microglial processes and dendritic spines. We also investigated potential differences in the morphology, density, or dynamics of dendritic spines in layer I/II primary sensory cortex of control and BGS alcohol exposed mice. We found that microglial process motility and contact with dendritic spines were not altered after BGS alcohol exposure. While the response of microglial processes toward tissue injury was not significantly altered by prior alcohol exposure, there was a trend suggesting that alcohol early in life may prime microglia to respond more quickly to secondary injury. Spine density, morphology, stability, and remodeling over time were not perturbed after BGS alcohol exposure. We demonstrate that after BGS alcohol exposure, the physiological functions of microglia and excitatory neurons remain intact in early adolescence.
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Affiliation(s)
- Elissa L Wong
- Department of Neuroscience, University of Rochester Medical Center, Rochester, New York, US.,Department of Environmental Medicine, University of Rochester Medical Center, New York, US
| | - Alexandra Strohm
- Department of Environmental Medicine, University of Rochester Medical Center, New York, US
| | - Jason Atlas
- Department of Neuroscience, University of Rochester Medical Center, Rochester, New York, US
| | - Cassandra Lamantia
- Department of Neuroscience, University of Rochester Medical Center, Rochester, New York, US
| | - Ania K Majewska
- Department of Neuroscience, University of Rochester Medical Center, Rochester, New York, US.,Center for Visual Science, University of Rochester Medical Center, Rochester, New York, US
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5
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Wang Y, Xi L. Chronic cranial window for photoacoustic imaging: a mini review. Vis Comput Ind Biomed Art 2021; 4:15. [PMID: 34037873 PMCID: PMC8155166 DOI: 10.1186/s42492-021-00081-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 04/27/2021] [Indexed: 12/31/2022] Open
Abstract
Photoacoustic (PA) microscopy is being increasingly used to visualize the microcirculation of the brain cortex at the micron level in living rodents. By combining it with long-term cranial window techniques, vasculature can be monitored over a period of days extending to months through a field of view. To fulfill the requirements of long-term in vivo PA imaging, the cranial window must involve a simple and rapid surgical procedure, biological compatibility, and sufficient optical-acoustic transparency, which are major challenges. Recently, several cranial window techniques have been reported for longitudinal PA imaging. Here, the development of chronic cranial windows for PA imaging is reviewed and its technical details are discussed, including window installation, imaging quality, and longitudinal stability.
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Affiliation(s)
- Yongchao Wang
- School of Physics, University of Electronic Science and Technology of China, Chengdu, 610054, Sichuan, China.,Department of Biomedical Engineering, Southern University of Science and Technology, Shenzhen, 518055, Guangdong, China
| | - Lei Xi
- Department of Biomedical Engineering, Southern University of Science and Technology, Shenzhen, 518055, Guangdong, China.
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6
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Seeger M, Soliman D, Aguirre J, Diot G, Wierzbowski J, Ntziachristos V. Pushing the boundaries of optoacoustic microscopy by total impulse response characterization. Nat Commun 2020; 11:2910. [PMID: 32518250 PMCID: PMC7283257 DOI: 10.1038/s41467-020-16565-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Accepted: 04/22/2020] [Indexed: 11/19/2022] Open
Abstract
Optical microscopy improves in resolution and signal-to-noise ratio by correcting for the system’s point spread function; a measure of how a point source is resolved, typically determined by imaging nanospheres. Optical-resolution optoacoustic (photoacoustic) microscopy could be similarly corrected, especially to account for the spatially-dependent signal distortions induced by the acoustic detection and the time-resolved and bi-polar nature of optoacoustic signals. Correction algorithms must therefore include the spatial dependence of signals’ origins and profiles in time, i.e. the four-dimensional total impulse response (TIR). However, such corrections have been so far impeded by a lack of efficient TIR-characterization methods. We introduce high-quality TIR determination based on spatially-distributed optoacoustic point sources (SOAPs), produced by scanning an optical focus on an axially-translatable 250 nm gold layer. Using a spatially-dependent TIR-correction improves the signal-to-noise ratio by >10 dB and the axial resolution by ~30%. This accomplishment displays a new performance paradigm for optoacoustic microscopy. Characterizing the total impulse response (TIR) of photoacoustic microscopes has been challenging due to difficulties distributing appropriate point sources. Here, the authors present a method for 3D generation of spatially-distributed optoacoustic point sources and show that subsequent TIR correction results in improved image quality.
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Affiliation(s)
- Markus Seeger
- Chair of Biological Imaging, TranslaTUM, Technical University of Munich, Ismaninger Straße 22, 81675, Munich, Germany.,Institute of Biological and Medical Imaging, Helmholtz Zentrum München, Ingolstädter Landstr. 1, 85764, Neuherberg, Germany
| | - Dominik Soliman
- Chair of Biological Imaging, TranslaTUM, Technical University of Munich, Ismaninger Straße 22, 81675, Munich, Germany.,Institute of Biological and Medical Imaging, Helmholtz Zentrum München, Ingolstädter Landstr. 1, 85764, Neuherberg, Germany
| | - Juan Aguirre
- Chair of Biological Imaging, TranslaTUM, Technical University of Munich, Ismaninger Straße 22, 81675, Munich, Germany.,Institute of Biological and Medical Imaging, Helmholtz Zentrum München, Ingolstädter Landstr. 1, 85764, Neuherberg, Germany
| | - Gael Diot
- Chair of Biological Imaging, TranslaTUM, Technical University of Munich, Ismaninger Straße 22, 81675, Munich, Germany.,Institute of Biological and Medical Imaging, Helmholtz Zentrum München, Ingolstädter Landstr. 1, 85764, Neuherberg, Germany
| | - Jakob Wierzbowski
- Walter Schottky Institute, Physics Department, Technical University of Munich, Am Coulombwall 4, 85748, Garching, Germany
| | - Vasilis Ntziachristos
- Chair of Biological Imaging, TranslaTUM, Technical University of Munich, Ismaninger Straße 22, 81675, Munich, Germany. .,Institute of Biological and Medical Imaging, Helmholtz Zentrum München, Ingolstädter Landstr. 1, 85764, Neuherberg, Germany.
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7
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Vinegoni C, Feruglio PF, Gryczynski I, Mazitschek R, Weissleder R. Fluorescence anisotropy imaging in drug discovery. Adv Drug Deliv Rev 2019; 151-152:262-288. [PMID: 29410158 PMCID: PMC6072632 DOI: 10.1016/j.addr.2018.01.019] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 01/29/2018] [Accepted: 01/30/2018] [Indexed: 12/15/2022]
Abstract
Non-invasive measurement of drug-target engagement can provide critical insights in the molecular pharmacology of small molecule drugs. Fluorescence polarization/fluorescence anisotropy measurements are commonly employed in protein/cell screening assays. However, the expansion of such measurements to the in vivo setting has proven difficult until recently. With the advent of high-resolution fluorescence anisotropy microscopy it is now possible to perform kinetic measurements of intracellular drug distribution and target engagement in commonly used mouse models. In this review we discuss the background, current advances and future perspectives in intravital fluorescence anisotropy measurements to derive pharmacokinetic and pharmacodynamic measurements in single cells and whole organs.
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Affiliation(s)
- Claudio Vinegoni
- Center for System Biology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.
| | - Paolo Fumene Feruglio
- Center for System Biology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA; Department of Neurological, Biomedical and Movement Sciences, University of Verona, Verona, Italy
| | - Ignacy Gryczynski
- University of North Texas Health Science Center, Institute for Molecular Medicine, Fort Worth, TX, United States
| | - Ralph Mazitschek
- Center for System Biology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Ralph Weissleder
- Center for System Biology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
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8
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Shirshin EA, Yakimov BP, Darvin ME, Omelyanenko NP, Rodionov SA, Gurfinkel YI, Lademann J, Fadeev VV, Priezzhev AV. Label-Free Multiphoton Microscopy: The Origin of Fluorophores and Capabilities for Analyzing Biochemical Processes. BIOCHEMISTRY (MOSCOW) 2019; 84:S69-S88. [PMID: 31213196 DOI: 10.1134/s0006297919140050] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Multiphoton microscopy (MPM) is a method of molecular imaging and specifically of intravital imaging that is characterized by high spatial resolution in combination with a greater depth of penetration into the tissue. MPM is a multimodal method based on detection of nonlinear optical signals - multiphoton fluorescence and optical harmonics - and also allows imaging with the use of the parameters of fluorescence decay kinetics. This review describes and discusses photophysical processes within major reporter molecules used in MPM with endogenous contrasts and summarizes several modern experiments that illustrate the capabilities of label-free MPM for molecular imaging of biochemical processes in connective tissue and cells.
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Affiliation(s)
- E A Shirshin
- Lomonosov Moscow State University, Faculty of Physics, Moscow, 119991, Russia. .,Institute of Spectroscopy, Russian Academy of Sciences, Troitsk, 108840, Moscow, Russia
| | - B P Yakimov
- Lomonosov Moscow State University, Faculty of Physics, Moscow, 119991, Russia
| | - M E Darvin
- Center of Experimental and Applied Cutaneous Physiology, Department of Dermatology, Venerology and Allergology, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, 10117, Germany
| | - N P Omelyanenko
- N. N. Priorov National Medical Research Center of Traumatology and Orthopaedics, Moscow, 127299, Russia
| | - S A Rodionov
- N. N. Priorov National Medical Research Center of Traumatology and Orthopaedics, Moscow, 127299, Russia
| | - Y I Gurfinkel
- Medical Scientific-Educational Center of Lomonosov Moscow State University, Moscow, 119192, Russia
| | - J Lademann
- Center of Experimental and Applied Cutaneous Physiology, Department of Dermatology, Venerology and Allergology, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, 10117, Germany
| | - V V Fadeev
- Lomonosov Moscow State University, Faculty of Physics, Moscow, 119991, Russia
| | - A V Priezzhev
- Lomonosov Moscow State University, Faculty of Physics, Moscow, 119991, Russia
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9
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Enhanced osteogenic differentiation of human mesenchymal stem cells on Ti surfaces with electrochemical nanopattern formation. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2019; 99:1174-1181. [PMID: 30889651 DOI: 10.1016/j.msec.2019.02.039] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Revised: 02/03/2019] [Accepted: 02/12/2019] [Indexed: 12/20/2022]
Abstract
Titanium (Ti) and its alloys are mainly used for dental and orthopedic applications due to their excellent biocompatibility and mechanical properties. However, their intrinsic bioinertness often quotes as a common complaint for biomedical applications. Herein, we produced nanopattern Ti surfaces with 10 nm nanopores in 120 nm dimples by electrochemical nanopattern formation (ENF), and evaluated the osteogenic differentiation of human mesenchymal stem cells (hMSCs) on the nanopattern Ti surfaces. The ENF surfaces were obtained by removing the TiO2 nanotube (NT) layers prepared by an anodization process. To determine the in vitro effects of the ENF surface, cell proliferation assay, alkaline phosphatase activity assay, alizarin red staining, western blotting, and immunocytochemistry were performed. Atomic force microscopy and scanning electron microscopy analysis show that the ENF surface has an ultrafine surface roughness with highly aligned nanoporous morphology. hMSCs on ENF surfaces exhibit increased proliferation and enhanced osteogenic differentiation as compared to the ordered TiO2 nanotubular and compact TiO2 surfaces. Surface modification with the ENF process is a promising technique for fabricating osteointegrative implant materials with a highly bioactive, rigid and purified nano surfaces.
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10
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Hu Q, Li P, Xiong Y, Wang Y, Lv X, Zeng S. Simultaneous two-plane, two-photon imaging based on spatial multiplexing. OPTICS LETTERS 2018; 43:4598-4601. [PMID: 30272692 DOI: 10.1364/ol.43.004598] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 08/24/2018] [Indexed: 06/08/2023]
Abstract
The two-photon microscope is a powerful tool in life science. Conventional two-photon microscopy can image only a plane of a particular axial position at a time. Axial scanning can get the volumetric information, but it gets signals from different axial positions serially, which means that the exposure time at every plane is limited. Here we demonstrate a novel method, to the best of our knowledge, that can simultaneously record images from two planes at different xyz positions. The demultiplexing of the signal is realized using a confocal strategy. The experimental results show that it can be used for simultaneous two-photon imaging at two focal planes with little cross talk.
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11
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Song SJ, Shin YC, Kim SE, Kwon IK, Lee JH, Hyon SH, Han DW, Kim B. Aligned laminin core-polydioxanone/collagen shell fiber matrices effective for neuritogenesis. Sci Rep 2018; 8:5570. [PMID: 29615798 PMCID: PMC5882927 DOI: 10.1038/s41598-018-23958-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Accepted: 03/23/2018] [Indexed: 11/21/2022] Open
Abstract
Neural tissue regeneration is a significant challenge, because severe nerve injury is quite difficult to regenerate spontaneously. Although, many studies have been devoted to promote nerve regeneration, there are still many technical challenges to achieve satisfactory results. In this study, we designed biomimetic matrices composed of aligned laminin core-polydioxanone/collagen shell (Lam-PDO/Col) fibers, which can provide both topographical and biochemical cues for promoting neuritogenesis. The aligned Lam-PDO/Col core-shell fiber matrices were fabricated by magnetic field-assisted electrospinning with the coaxial system, and their potential as biofunctional scaffolds for promoting neuritogenesis was explored. It was demonstrated that the aligned Lam-PDO/Col core-shell fibers were successfully fabricated, and the laminin in the core of fibers was steadily and continuously released from fibers. In addition, the cellular behaviors of hippocampal neuronal cells on the matrices were significantly enhanced. Moreover, the aligned Lam-PDO/Col fiber matrices effectively improved and guided neurite outgrowth as well as the neurogenic differentiation by providing both topographical and biochemical cues through aligned fiber structure and sustained release of laminin. Collectively, it is suggested that the aligned Lam-PDO/Col core-shell fiber matrices are one of the most promising approaches for promoting neuritogenesis and neural tissue regeneration.
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Affiliation(s)
- Su-Jin Song
- Department of Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busan, 46241, Republic of Korea
| | - Yong Cheol Shin
- Research Center for Energy Convergence Technology, Pusan National University, Busan, 46241, Republic of Korea
| | - Sung Eun Kim
- Department of Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busan, 46241, Republic of Korea
| | - Il Keun Kwon
- Department of Dental Materials, School of Dentistry, Kyung Hee University, Seoul, 02447, Republic of Korea
| | - Jong-Ho Lee
- Department of Oral and Maxillofacial Surgery, School of Dentistry, Seoul National University, Seoul, 03080, Republic of Korea
| | - Suong-Hyu Hyon
- Center for Fiber and Textile Science, Kyoto Institute of Technology, Matsugasaki, Kyoto, 606-8585, Japan
| | - Dong-Wook Han
- Department of Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busan, 46241, Republic of Korea.
| | - Bongju Kim
- Dental Life Science Research Institute, Seoul National University Dental Hospital, Seoul, 03080, Republic of Korea.
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12
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Shin YC, Kim C, Song SJ, Jun S, Kim CS, Hong SW, Hyon SH, Han DW, Oh JW. Ternary Aligned Nanofibers of RGD Peptide-Displaying M13 Bacteriophage/PLGA/Graphene Oxide for Facilitated Myogenesis. Nanotheranostics 2018; 2:144-156. [PMID: 29577018 PMCID: PMC5865268 DOI: 10.7150/ntno.22433] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Accepted: 12/23/2017] [Indexed: 12/14/2022] Open
Abstract
Recently, there have been tremendous efforts to develop the biofunctional scaffolds by incorporating various biochemical factors. In the present study, we fabricated poly(lactic-co-glycolic acid) (PLGA) nanofiber sheets decorated with graphene oxide (GO) and RGD peptide. The decoration of GO and RGD peptide was readily achieved by using RGD peptide-displaying M13 bacteriophage (RGD-M13 phage) and electrospinning. Furthermore, the aligned GO-decorated PLGA/RGD peptide (GO-PLGA/RGD) ternary nanofiber sheets were prepared by magnetic field-assisted electrospinning, and their potentials as bifunctional scaffolds for facilitating myogenesis were explored. We characterized the physicochemical and mechanical properties of the sheets by scanning electron microscopy, Raman spectroscopy, contact angle measurement, and tensile test. In addition, the C2C12 skeletal myoblasts were cultured on the aligned GO-PLGA/RGD nanofiber sheets, and their cellular behaviors, including initial attachment, proliferation and myogenic differentiation, were evaluated. Our results revealed that the GO-PLGA/RGD nanofiber sheets had suitable physicochemical and mechanical properties for supporting cell growth, and could significantly promote the spontaneous myogenic differentiation of C2C12 skeletal myoblasts. Moreover, it was revealed that the myogenic differentiation was further accelerated on the aligned GO-PLGA/RGD nanofiber sheets due to the synergistic effects of RGD peptide, GO and aligned nanofiber structure. Therefore, , it is suggested that the aligned GO-PLGA/RGD ternary nanofiber sheets are one of the most promising approaches for facilitating myogenesis and promoting skeletal tissue regeneration.
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Affiliation(s)
- Yong Cheol Shin
- Research Center for Energy Convergence Technology, Pusan National University, Busan 46241, Republic of Korea
| | - Chuntae Kim
- Department of Nanofusion Technology, College of Nanoscience & Nanotechnology, Pusan National University, Busan 46241, Republic of Korea
| | - Su-Jin Song
- Department of Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busan 46241, Republic of Korea
| | - Seungwon Jun
- Department of Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busan 46241, Republic of Korea
| | - Chang-Seok Kim
- Department of Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busan 46241, Republic of Korea
| | - Suck Won Hong
- Department of Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busan 46241, Republic of Korea
| | - Suong-Hyu Hyon
- Center for Fiber and Textile Science, Kyoto Institute of Technology, Matsugasaki, Kyoto 606-8585, Japan
| | - Dong-Wook Han
- Department of Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busan 46241, Republic of Korea
| | - Jin-Woo Oh
- Department of Nanofusion Technology, College of Nanoscience & Nanotechnology, Pusan National University, Busan 46241, Republic of Korea
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13
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Dunn KW, Sutton TA, Sandoval RM. Live-Animal Imaging of Renal Function by Multiphoton Microscopy. ACTA ACUST UNITED AC 2018; 83:12.9.1-12.9.25. [PMID: 29345326 DOI: 10.1002/cpcy.32] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Intravital microscopy, microscopy of living animals, is a powerful research technique that combines the resolution and sensitivity found in microscopic studies of cultured cells with the relevance and systemic influences of cells in the context of the intact animal. The power of intravital microscopy has recently been extended with the development of multiphoton fluorescence microscopy systems capable of collecting optical sections from deep within the kidney at subcellular resolution, supporting high-resolution characterizations of the structure and function of glomeruli, tubules, and vasculature in the living kidney. Fluorescent probes are administered to an anesthetized, surgically prepared animal, followed by image acquisition for up to 3 hr. Images are transferred via a high-speed network to specialized computer systems for digital image analysis. This general approach can be used with different combinations of fluorescent probes to evaluate processes such as glomerular permeability, proximal tubule endocytosis, microvascular flow, vascular permeability, mitochondrial function, and cellular apoptosis/necrosis. © 2018 by John Wiley & Sons, Inc.
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Affiliation(s)
- Kenneth W Dunn
- Indiana University School of Medicine, Indianapolis, Indiana
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14
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Shin YC, Kang SH, Lee JH, Kim B, Hong SW, Han DW. Three-dimensional graphene oxide-coated polyurethane foams beneficial to myogenesis. JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION 2017; 29:762-774. [PMID: 28657493 DOI: 10.1080/09205063.2017.1348738] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The development of three dimensional (3D) scaffolds for promoting and stimulating cell growth is one of the greatest concerns in biomedical and tissue engineering. In the present study, novel biomimetic 3D scaffolds composed of polyurethane (PU) foam and graphene oxide (GO) nanosheets were designed, and their potential as 3D scaffolds for skeletal tissue regeneration was explored. The GO-coated PU foams (GO-PU foams) were characterized by scanning electron microscopy and Raman spectroscopy. It was revealed that the 3D GO-PU foams consisted of an interconnected foam-like network structure with an approximate 300 μm pore size, and the GO was uniformly distributed in the PU foams. On the other hand, the myogenic stimulatory effects of GO on skeletal myoblasts were also investigated. Moreover, the cellular behaviors of the skeletal myoblasts within the 3D GO-PU foams were evaluated by immunofluorescence analysis. Our findings showed that GO can significantly promote spontaneous myogenic differentiation without any myogenic factors, and the 3D GO-PU foams can provide a suitable 3D microenvironment for cell growth. Furthermore, the 3D GO-PU foams stimulated spontaneous myogenic differentiation via the myogenic stimulatory effects of GO. Therefore, this study suggests that the 3D GO-PU foams are beneficial to myogenesis, and can be used as biomimetic 3D scaffolds for skeletal tissue engineering.
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Affiliation(s)
- Yong Cheol Shin
- a Department of Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology , Pusan National University , Busan , Korea
| | - Seok Hee Kang
- a Department of Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology , Pusan National University , Busan , Korea
| | - Jong Ho Lee
- b Center for Biomaterials, Biomedical Research Institute , Korea Institute of Science and Technology , Seoul , Korea
| | - Bongju Kim
- c Dental Life Science Research Institute & Clinical Translational Research Center for Dental Science , Seoul National University Dental Hospital , Seoul , Korea
| | - Suck Won Hong
- a Department of Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology , Pusan National University , Busan , Korea.,d Department of Optics and Mechatronics Engineering, BK21+ Nano-Integrated Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology , Pusan National University , Busan , Korea
| | - Dong-Wook Han
- a Department of Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology , Pusan National University , Busan , Korea.,d Department of Optics and Mechatronics Engineering, BK21+ Nano-Integrated Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology , Pusan National University , Busan , Korea
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15
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Lepore M, Portaccio M, Delfino I, Sironi L, La Gatta A, D'Agostino A, Izzo E, Schiraldi C. Physico-optical properties of a crosslinked hyaluronic acid scaffold for biomedical applications. J Appl Polym Sci 2017. [DOI: 10.1002/app.45243] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Maria Lepore
- Dipartimento di Medicina Sperimentale; Università della Campania “Luigi Vanvitelli; Naples I-80123 Italy
| | - Marianna Portaccio
- Dipartimento di Medicina Sperimentale; Università della Campania “Luigi Vanvitelli; Naples I-80123 Italy
| | - Ines Delfino
- Dipartimento di Scienze Ecologiche e Biologiche; Università della Tuscia; Viterbo I-01100 Italy
| | - Laura Sironi
- Dipartimento di Fisica “G. Occhialini”; Università degli Studi di Milano-Bicocca; Milano I-20126 Italy
| | - Annalisa La Gatta
- Dipartimento di Medicina Sperimentale; Università della Campania “Luigi Vanvitelli; Naples I-80123 Italy
| | - Antonella D'Agostino
- Dipartimento di Medicina Sperimentale; Università della Campania “Luigi Vanvitelli; Naples I-80123 Italy
| | - E. Izzo
- Dipartimento di Medicina Sperimentale; Università della Campania “Luigi Vanvitelli; Naples I-80123 Italy
| | - Chiara Schiraldi
- Dipartimento di Medicina Sperimentale; Università della Campania “Luigi Vanvitelli; Naples I-80123 Italy
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16
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Shin YC, Kim J, Kim SE, Song SJ, Hong SW, Oh JW, Lee J, Park JC, Hyon SH, Han DW. RGD peptide and graphene oxide co-functionalized PLGA nanofiber scaffolds for vascular tissue engineering. Regen Biomater 2017; 4:159-166. [PMID: 28740639 PMCID: PMC5516678 DOI: 10.1093/rb/rbx001] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Revised: 01/02/2017] [Accepted: 01/04/2017] [Indexed: 12/04/2022] Open
Abstract
In recent years, much research has been suggested and examined for the development of tissue engineering scaffolds to promote cellular behaviors. In our study, RGD peptide and graphene oxide (GO) co-functionalized poly(lactide-co-glycolide, PLGA) (RGD-GO-PLGA) nanofiber mats were fabricated via electrospinning, and their physicochemical and thermal properties were characterized to explore their potential as biofunctional scaffolds for vascular tissue engineering. Scanning electron microscopy images revealed that the RGD-GO-PLGA nanofiber mats were readily fabricated and composed of random-oriented electrospun nanofibers with average diameter of 558 nm. The successful co-functionalization of RGD peptide and GO into the PLGA nanofibers was confirmed by Fourier-transform infrared spectroscopic analysis. Moreover, the surface hydrophilicity of the nanofiber mats was markedly increased by co-functionalizing with RGD peptide and GO. It was found that the mats were thermally stable under the cell culture condition. Furthermore, the initial attachment and proliferation of primarily cultured vascular smooth muscle cells (VSMCs) on the RGD-GO-PLGA nanofiber mats were evaluated. It was revealed that the RGD-GO-PLGA nanofiber mats can effectively promote the growth of VSMCs. In conclusion, our findings suggest that the RGD-GO-PLGA nanofiber mats can be promising candidates for tissue engineering scaffolds effective for the regeneration of vascular smooth muscle.
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Affiliation(s)
| | | | | | - Su-Jin Song
- Department of Cogno-Mechatronics Engineering
| | - Suck Won Hong
- Department of Cogno-Mechatronics Engineering.,Department of Optics and Mechatronics Engineering
| | - Jin-Woo Oh
- Department of Nanoenergy Engineering, College of Nanoscience and Nanotechnology, Pusan National University, Busan 46241, Korea
| | - Jaebeom Lee
- Department of Cogno-Mechatronics Engineering.,Department of Optics and Mechatronics Engineering
| | | | - Suong-Hyu Hyon
- Center for Fiber and Textile Science, Kyoto Institute of Technology, Matsugasaki, Kyoto 606-8585, Japan
| | - Dong-Wook Han
- Department of Cogno-Mechatronics Engineering.,Department of Optics and Mechatronics Engineering
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17
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Bosch M, Castro J, Sur M, Hayashi Y. Photomarking Relocalization Technique for Correlated Two-Photon and Electron Microcopy Imaging of Single Stimulated Synapses. Methods Mol Biol 2017; 1538:185-214. [PMID: 27943192 DOI: 10.1007/978-1-4939-6688-2_14] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Synapses learn and remember by persistent modifications of their internal structures and composition but, due to their small size, it is difficult to observe these changes at the ultrastructural level in real time. Two-photon fluorescence microscopy (2PM) allows time-course live imaging of individual synapses but lacks ultrastructural resolution. Electron microscopy (EM) allows the ultrastructural imaging of subcellular components but cannot detect fluorescence and lacks temporal resolution. Here, we describe a combination of procedures designed to achieve the correlated imaging of the same individual synapse under both 2PM and EM. This technique permits the selective stimulation and live imaging of a single dendritic spine and the subsequent localization of the same spine in EM ultrathin serial sections. Landmarks created through a photomarking method based on the 2-photon-induced precipitation of an electrodense compound are used to unequivocally localize the stimulated synapse. This technique was developed to image, for the first time, the ultrastructure of the postsynaptic density in which long-term potentiation was selectively induced just seconds or minutes before, but it can be applied for the study of any biological process that requires the precise relocalization of micron-wide structures for their correlated imaging with 2PM and EM.
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Affiliation(s)
- Miquel Bosch
- RIKEN-MIT Neuroscience Research Center, Massachusetts Institute of Technology, Cambridge, MA, USA.
- The Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA.
- Institute for Bioengineering of Catalonia, Barcelona, Spain.
| | - Jorge Castro
- The Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Mriganka Sur
- The Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Yasunori Hayashi
- RIKEN-MIT Neuroscience Research Center, Massachusetts Institute of Technology, Cambridge, MA, USA
- The Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA
- Brain Science Institute, RIKEN, Wako, Saitama, Japan
- Saitama University Brain Science Institute, Saitama University, Saitama, Japan
- School of Life Science, South China Normal University, Guangzhou, China
- Department of Pharmacology, Faculty of Medicine, Kyoto University, Kyoto 606-8501, Japan
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18
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Kim MJ, Shin YC, Lee JH, Jun SW, Kim CS, Lee Y, Park JC, Lee SH, Park KD, Han DW. Multiphoton imaging of myogenic differentiation in gelatin-based hydrogels as tissue engineering scaffolds. Biomater Res 2016; 20:2. [PMID: 26783450 PMCID: PMC4716633 DOI: 10.1186/s40824-016-0050-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Accepted: 01/04/2016] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND Hydrogels can serve as three-dimensional (3D) scaffolds for cell culture and be readily injected into the body. Recent advances in the image technology for 3D scaffolds like hydrogels have attracted considerable attention to overcome the drawbacks of ordinary imaging technologies such as optical and fluorescence microscopy. Multiphoton microscopy (MPM) is an effective method based on the excitation of two-photons. In the present study, C2C12 myoblasts differentiated in 3D gelatin hydroxyphenylpropionic acid (GHPA) hydrogels were imaged by using a custom-built multiphoton excitation fluorescence microscopy to compare the difference in the imaging capacity between conventional microscopy and MPM. RESULTS The physicochemical properties of GHPA hydrogels were characterized by using scanning electron microscopy and Fourier-transform infrared spectroscopy. In addition, the cell viability and proliferation of C2C12 myoblasts cultured in the GHPA hydrogels were analyzed by using Live/Dead Cell and CCK-8 assays, respectively. It was found that C2C12 cells were well grown and normally proliferated in the hydrogels. Furthermore, the hydrogels were shown to be suitable to facilitate the myogenic differentiation of C2C12 cells incubated in differentiation media, which had been corroborated by MPM. It was very hard to get clear images from a fluorescence microscope. CONCLUSIONS Our findings suggest that the gelatin-based hydrogels can be beneficially utilized as 3D scaffolds for skeletal muscle engineering and that MPM can be effectively applied to imaging technology for tissue regeneration.
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Affiliation(s)
- Min Jeong Kim
- />Department of Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busan, 46241 Korea
| | - Yong Cheol Shin
- />Department of Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busan, 46241 Korea
| | - Jong Ho Lee
- />Department of Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busan, 46241 Korea
| | - Seung Won Jun
- />Department of Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busan, 46241 Korea
| | - Chang-Seok Kim
- />Department of Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busan, 46241 Korea
| | - Yunki Lee
- />Department of Molecular Science and Technology, Ajou University, Suwon, 16499 Korea
| | - Jong-Chul Park
- />Department of Medical Engineering, Cellbiocontrol Laboratory, Yonsei University College of Medicine, Seoul, 03722 Korea
| | - Soo-Hong Lee
- />Department of Biomedical Science, CHA University, Gyeonggi-do, 11160 Korea
| | - Ki Dong Park
- />Department of Molecular Science and Technology, Ajou University, Suwon, 16499 Korea
| | - Dong-Wook Han
- />Department of Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busan, 46241 Korea
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19
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Haynes-Gimore N, Banach M, Brown E, Dawes R, Edholm ES, Kim M, Robert J. Semi-solid tumor model in Xenopus laevis/gilli cloned tadpoles for intravital study of neovascularization, immune cells and melanophore infiltration. Dev Biol 2015; 408:205-12. [PMID: 25601449 PMCID: PMC4506265 DOI: 10.1016/j.ydbio.2015.01.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Revised: 10/29/2014] [Accepted: 01/08/2015] [Indexed: 11/18/2022]
Abstract
Tumors have the ability to grow as a self-sustaining entity within the body. This autonomy is in part accomplished by the tumor cells ability to induce the formation of new blood vessels (angiogenesis) and by controlling cell trafficking inside the tumor mass. These abilities greatly reduce the efficacy of many cancer therapies and pose challenges for the development of more effective cancer treatments. Hence, there is a need for animal models suitable for direct microscopy observation of blood vessel formation and cell trafficking, especially during early stages of tumor establishment. Here, we have developed a reliable and cost effective tumor model system in tadpoles of the amphibian Xenopus laevis. Tadpoles are ideally suited for direct microscopy observation because of their small size and transparency. Using the thymic lymphoid tumor line 15/0 derived from, and transplantable into, the X. laevis/gilli isogenic clone LG-15, we have adapted a system that consists in transplanting 15/0 tumor cells embedded into rat collagen under the dorsal skin of LG-15 tadpole recipients. This system recapitulates many facets of mammalian tumorigenesis and permits real time visualization of the active formation of the tumor microenvironment induced by 15/0 tumor cells including neovascularization, collagen rearrangements as well as infiltration of immune cells and melanophores.
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Affiliation(s)
- Nikesha Haynes-Gimore
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642, USA; Department of Pathology, University of Rochester Medical Center, Rochester, USA
| | - Maureen Banach
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Edward Brown
- Department of Neurobiology and Anatomy, University of Rochester Medical Center, Rochester, USA
| | - Ryan Dawes
- Department of Neurobiology and Anatomy, University of Rochester Medical Center, Rochester, USA
| | - Eva-Stina Edholm
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Minsoo Kim
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642, USA; Center for Vaccine Biology and Immunology, Rochester, USA
| | - Jacques Robert
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642, USA.
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20
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Awasthi S, Izu LT, Mao Z, Jian Z, Landas T, Lerner A, Shimkunas R, Woldeyesus R, Bossuyt J, Wood BM, Chen YJ, Matthews DL, Lieu DK, Chiamvimonvat N, Lam KS, Chen-Izu Y, Chan JW. Multimodal SHG-2PF Imaging of Microdomain Ca2+-Contraction Coupling in Live Cardiac Myocytes. Circ Res 2015; 118:e19-28. [PMID: 26643875 DOI: 10.1161/circresaha.115.307919] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Accepted: 12/07/2015] [Indexed: 01/24/2023]
Abstract
RATIONALE Cardiac myocyte contraction is caused by Ca(2+) binding to troponin C, which triggers the cross-bridge power stroke and myofilament sliding in sarcomeres. Synchronized Ca(2+) release causes whole cell contraction and is readily observable with current microscopy techniques. However, it is unknown whether localized Ca(2+) release, such as Ca(2+) sparks and waves, can cause local sarcomere contraction. Contemporary imaging methods fall short of measuring microdomain Ca(2+)-contraction coupling in live cardiac myocytes. OBJECTIVE To develop a method for imaging sarcomere level Ca(2+)-contraction coupling in healthy and disease model cardiac myocytes. METHODS AND RESULTS Freshly isolated cardiac myocytes were loaded with the Ca(2+)-indicator fluo-4. A confocal microscope equipped with a femtosecond-pulsed near-infrared laser was used to simultaneously excite second harmonic generation from A-bands of myofibrils and 2-photon fluorescence from fluo-4. Ca(2+) signals and sarcomere strain correlated in space and time with short delays. Furthermore, Ca(2+) sparks and waves caused contractions in subcellular microdomains, revealing a previously underappreciated role for these events in generating subcellular strain during diastole. Ca(2+) activity and sarcomere strain were also imaged in paced cardiac myocytes under mechanical load, revealing spontaneous Ca(2+) waves and correlated local contraction in pressure-overload-induced cardiomyopathy. CONCLUSIONS Multimodal second harmonic generation 2-photon fluorescence microscopy enables the simultaneous observation of Ca(2+) release and mechanical strain at the subsarcomere level in living cardiac myocytes. The method benefits from the label-free nature of second harmonic generation, which allows A-bands to be imaged independently of T-tubule morphology and simultaneously with Ca(2+) indicators. Second harmonic generation 2-photon fluorescence imaging is widely applicable to the study of Ca(2+)-contraction coupling and mechanochemotransduction in both health and disease.
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Affiliation(s)
- Samir Awasthi
- From the Center for Biophotonics (S.A., Z.M., A.L., D.L.M., J.W.C.), Division of Cardiology (D.K.L., N.C., Y.C.-I.), Division of Hematology/Oncology, Department of Internal Medicine (K.S.L.), and Department of Pathology and Laboratory Medicine (J.W.C.), UC Davis School of Medicine, University of California, Davis, Sacramento; and Departments of Pharmacology (L.T.I., Z.J., T.L., J.B., B.W., Y.-J.C., Y.C.-I.), Biomedical Engineering (S.A., R.S., R.W., Y.C.-I.), Biochemistry and Molecular Medicine (K.S.L.), and Microsurgery Core (Y.-J.C.), University of California, Davis
| | - Leighton T Izu
- From the Center for Biophotonics (S.A., Z.M., A.L., D.L.M., J.W.C.), Division of Cardiology (D.K.L., N.C., Y.C.-I.), Division of Hematology/Oncology, Department of Internal Medicine (K.S.L.), and Department of Pathology and Laboratory Medicine (J.W.C.), UC Davis School of Medicine, University of California, Davis, Sacramento; and Departments of Pharmacology (L.T.I., Z.J., T.L., J.B., B.W., Y.-J.C., Y.C.-I.), Biomedical Engineering (S.A., R.S., R.W., Y.C.-I.), Biochemistry and Molecular Medicine (K.S.L.), and Microsurgery Core (Y.-J.C.), University of California, Davis
| | - Ziliang Mao
- From the Center for Biophotonics (S.A., Z.M., A.L., D.L.M., J.W.C.), Division of Cardiology (D.K.L., N.C., Y.C.-I.), Division of Hematology/Oncology, Department of Internal Medicine (K.S.L.), and Department of Pathology and Laboratory Medicine (J.W.C.), UC Davis School of Medicine, University of California, Davis, Sacramento; and Departments of Pharmacology (L.T.I., Z.J., T.L., J.B., B.W., Y.-J.C., Y.C.-I.), Biomedical Engineering (S.A., R.S., R.W., Y.C.-I.), Biochemistry and Molecular Medicine (K.S.L.), and Microsurgery Core (Y.-J.C.), University of California, Davis
| | - Zhong Jian
- From the Center for Biophotonics (S.A., Z.M., A.L., D.L.M., J.W.C.), Division of Cardiology (D.K.L., N.C., Y.C.-I.), Division of Hematology/Oncology, Department of Internal Medicine (K.S.L.), and Department of Pathology and Laboratory Medicine (J.W.C.), UC Davis School of Medicine, University of California, Davis, Sacramento; and Departments of Pharmacology (L.T.I., Z.J., T.L., J.B., B.W., Y.-J.C., Y.C.-I.), Biomedical Engineering (S.A., R.S., R.W., Y.C.-I.), Biochemistry and Molecular Medicine (K.S.L.), and Microsurgery Core (Y.-J.C.), University of California, Davis
| | - Trevor Landas
- From the Center for Biophotonics (S.A., Z.M., A.L., D.L.M., J.W.C.), Division of Cardiology (D.K.L., N.C., Y.C.-I.), Division of Hematology/Oncology, Department of Internal Medicine (K.S.L.), and Department of Pathology and Laboratory Medicine (J.W.C.), UC Davis School of Medicine, University of California, Davis, Sacramento; and Departments of Pharmacology (L.T.I., Z.J., T.L., J.B., B.W., Y.-J.C., Y.C.-I.), Biomedical Engineering (S.A., R.S., R.W., Y.C.-I.), Biochemistry and Molecular Medicine (K.S.L.), and Microsurgery Core (Y.-J.C.), University of California, Davis
| | - Aaron Lerner
- From the Center for Biophotonics (S.A., Z.M., A.L., D.L.M., J.W.C.), Division of Cardiology (D.K.L., N.C., Y.C.-I.), Division of Hematology/Oncology, Department of Internal Medicine (K.S.L.), and Department of Pathology and Laboratory Medicine (J.W.C.), UC Davis School of Medicine, University of California, Davis, Sacramento; and Departments of Pharmacology (L.T.I., Z.J., T.L., J.B., B.W., Y.-J.C., Y.C.-I.), Biomedical Engineering (S.A., R.S., R.W., Y.C.-I.), Biochemistry and Molecular Medicine (K.S.L.), and Microsurgery Core (Y.-J.C.), University of California, Davis
| | - Rafael Shimkunas
- From the Center for Biophotonics (S.A., Z.M., A.L., D.L.M., J.W.C.), Division of Cardiology (D.K.L., N.C., Y.C.-I.), Division of Hematology/Oncology, Department of Internal Medicine (K.S.L.), and Department of Pathology and Laboratory Medicine (J.W.C.), UC Davis School of Medicine, University of California, Davis, Sacramento; and Departments of Pharmacology (L.T.I., Z.J., T.L., J.B., B.W., Y.-J.C., Y.C.-I.), Biomedical Engineering (S.A., R.S., R.W., Y.C.-I.), Biochemistry and Molecular Medicine (K.S.L.), and Microsurgery Core (Y.-J.C.), University of California, Davis
| | - Rahwa Woldeyesus
- From the Center for Biophotonics (S.A., Z.M., A.L., D.L.M., J.W.C.), Division of Cardiology (D.K.L., N.C., Y.C.-I.), Division of Hematology/Oncology, Department of Internal Medicine (K.S.L.), and Department of Pathology and Laboratory Medicine (J.W.C.), UC Davis School of Medicine, University of California, Davis, Sacramento; and Departments of Pharmacology (L.T.I., Z.J., T.L., J.B., B.W., Y.-J.C., Y.C.-I.), Biomedical Engineering (S.A., R.S., R.W., Y.C.-I.), Biochemistry and Molecular Medicine (K.S.L.), and Microsurgery Core (Y.-J.C.), University of California, Davis
| | - Julie Bossuyt
- From the Center for Biophotonics (S.A., Z.M., A.L., D.L.M., J.W.C.), Division of Cardiology (D.K.L., N.C., Y.C.-I.), Division of Hematology/Oncology, Department of Internal Medicine (K.S.L.), and Department of Pathology and Laboratory Medicine (J.W.C.), UC Davis School of Medicine, University of California, Davis, Sacramento; and Departments of Pharmacology (L.T.I., Z.J., T.L., J.B., B.W., Y.-J.C., Y.C.-I.), Biomedical Engineering (S.A., R.S., R.W., Y.C.-I.), Biochemistry and Molecular Medicine (K.S.L.), and Microsurgery Core (Y.-J.C.), University of California, Davis
| | - Brent M Wood
- From the Center for Biophotonics (S.A., Z.M., A.L., D.L.M., J.W.C.), Division of Cardiology (D.K.L., N.C., Y.C.-I.), Division of Hematology/Oncology, Department of Internal Medicine (K.S.L.), and Department of Pathology and Laboratory Medicine (J.W.C.), UC Davis School of Medicine, University of California, Davis, Sacramento; and Departments of Pharmacology (L.T.I., Z.J., T.L., J.B., B.W., Y.-J.C., Y.C.-I.), Biomedical Engineering (S.A., R.S., R.W., Y.C.-I.), Biochemistry and Molecular Medicine (K.S.L.), and Microsurgery Core (Y.-J.C.), University of California, Davis
| | - Yi-Je Chen
- From the Center for Biophotonics (S.A., Z.M., A.L., D.L.M., J.W.C.), Division of Cardiology (D.K.L., N.C., Y.C.-I.), Division of Hematology/Oncology, Department of Internal Medicine (K.S.L.), and Department of Pathology and Laboratory Medicine (J.W.C.), UC Davis School of Medicine, University of California, Davis, Sacramento; and Departments of Pharmacology (L.T.I., Z.J., T.L., J.B., B.W., Y.-J.C., Y.C.-I.), Biomedical Engineering (S.A., R.S., R.W., Y.C.-I.), Biochemistry and Molecular Medicine (K.S.L.), and Microsurgery Core (Y.-J.C.), University of California, Davis
| | - Dennis L Matthews
- From the Center for Biophotonics (S.A., Z.M., A.L., D.L.M., J.W.C.), Division of Cardiology (D.K.L., N.C., Y.C.-I.), Division of Hematology/Oncology, Department of Internal Medicine (K.S.L.), and Department of Pathology and Laboratory Medicine (J.W.C.), UC Davis School of Medicine, University of California, Davis, Sacramento; and Departments of Pharmacology (L.T.I., Z.J., T.L., J.B., B.W., Y.-J.C., Y.C.-I.), Biomedical Engineering (S.A., R.S., R.W., Y.C.-I.), Biochemistry and Molecular Medicine (K.S.L.), and Microsurgery Core (Y.-J.C.), University of California, Davis
| | - Deborah K Lieu
- From the Center for Biophotonics (S.A., Z.M., A.L., D.L.M., J.W.C.), Division of Cardiology (D.K.L., N.C., Y.C.-I.), Division of Hematology/Oncology, Department of Internal Medicine (K.S.L.), and Department of Pathology and Laboratory Medicine (J.W.C.), UC Davis School of Medicine, University of California, Davis, Sacramento; and Departments of Pharmacology (L.T.I., Z.J., T.L., J.B., B.W., Y.-J.C., Y.C.-I.), Biomedical Engineering (S.A., R.S., R.W., Y.C.-I.), Biochemistry and Molecular Medicine (K.S.L.), and Microsurgery Core (Y.-J.C.), University of California, Davis
| | - Nipavan Chiamvimonvat
- From the Center for Biophotonics (S.A., Z.M., A.L., D.L.M., J.W.C.), Division of Cardiology (D.K.L., N.C., Y.C.-I.), Division of Hematology/Oncology, Department of Internal Medicine (K.S.L.), and Department of Pathology and Laboratory Medicine (J.W.C.), UC Davis School of Medicine, University of California, Davis, Sacramento; and Departments of Pharmacology (L.T.I., Z.J., T.L., J.B., B.W., Y.-J.C., Y.C.-I.), Biomedical Engineering (S.A., R.S., R.W., Y.C.-I.), Biochemistry and Molecular Medicine (K.S.L.), and Microsurgery Core (Y.-J.C.), University of California, Davis
| | - Kit S Lam
- From the Center for Biophotonics (S.A., Z.M., A.L., D.L.M., J.W.C.), Division of Cardiology (D.K.L., N.C., Y.C.-I.), Division of Hematology/Oncology, Department of Internal Medicine (K.S.L.), and Department of Pathology and Laboratory Medicine (J.W.C.), UC Davis School of Medicine, University of California, Davis, Sacramento; and Departments of Pharmacology (L.T.I., Z.J., T.L., J.B., B.W., Y.-J.C., Y.C.-I.), Biomedical Engineering (S.A., R.S., R.W., Y.C.-I.), Biochemistry and Molecular Medicine (K.S.L.), and Microsurgery Core (Y.-J.C.), University of California, Davis
| | - Ye Chen-Izu
- From the Center for Biophotonics (S.A., Z.M., A.L., D.L.M., J.W.C.), Division of Cardiology (D.K.L., N.C., Y.C.-I.), Division of Hematology/Oncology, Department of Internal Medicine (K.S.L.), and Department of Pathology and Laboratory Medicine (J.W.C.), UC Davis School of Medicine, University of California, Davis, Sacramento; and Departments of Pharmacology (L.T.I., Z.J., T.L., J.B., B.W., Y.-J.C., Y.C.-I.), Biomedical Engineering (S.A., R.S., R.W., Y.C.-I.), Biochemistry and Molecular Medicine (K.S.L.), and Microsurgery Core (Y.-J.C.), University of California, Davis.
| | - James W Chan
- From the Center for Biophotonics (S.A., Z.M., A.L., D.L.M., J.W.C.), Division of Cardiology (D.K.L., N.C., Y.C.-I.), Division of Hematology/Oncology, Department of Internal Medicine (K.S.L.), and Department of Pathology and Laboratory Medicine (J.W.C.), UC Davis School of Medicine, University of California, Davis, Sacramento; and Departments of Pharmacology (L.T.I., Z.J., T.L., J.B., B.W., Y.-J.C., Y.C.-I.), Biomedical Engineering (S.A., R.S., R.W., Y.C.-I.), Biochemistry and Molecular Medicine (K.S.L.), and Microsurgery Core (Y.-J.C.), University of California, Davis.
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21
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Shin YC, Lee JH, Kim MJ, Hong SW, Kim B, Hyun JK, Choi YS, Park JC, Han DW. Stimulating effect of graphene oxide on myogenesis of C2C12 myoblasts on RGD peptide-decorated PLGA nanofiber matrices. J Biol Eng 2015; 9:22. [PMID: 26609319 PMCID: PMC4659147 DOI: 10.1186/s13036-015-0020-1] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 11/17/2015] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND In the field of biomedical engineering, many studies have focused on the possible applications of graphene and related nanomaterials due to their potential for use as scaffolds, coating materials and delivery carriers. On the other hand, electrospun nanofiber matrices composed of diverse biocompatible polymers have attracted tremendous attention for tissue engineering and regenerative medicine. However, their combination is intriguing and still challenging. RESULTS In the present study, we fabricated nanofiber matrices composed of M13 bacteriophage with RGD peptide displayed on its surface (RGD-M13 phage) and poly(lactic-co-glycolic acid, PLGA) and characterized their physicochemical properties. In addition, the effect of graphene oxide (GO) on the cellular behaviors of C2C12 myoblasts, which were cultured on PLGA decorated with RGD-M13 phage (RGD/PLGA) nanofiber matrices, was investigated. Our results revealed that the RGD/PLGA nanofiber matrices have suitable physicochemical properties as a tissue engineering scaffold and the growth of C2C12 myoblasts were significantly enhanced on the matrices. Moreover, the myogenic differentiation of C2C12 myoblasts was substantially stimulated when they were cultured on the RGD/PLGA matrices in the presence of GO. CONCLUSION In conclusion, these findings propose that the combination of RGD/PLGA nanofiber matrices and GO can be used as a promising strategy for skeletal tissue engineering and regeneration.
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Affiliation(s)
- Yong Cheol Shin
- />Department of Optics and Mechatronics Engineering, BK21+ Nano-Integrated Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busandaehak-ro 63beon-gil, Geumjeong-gu, Busan, 609-735 >Korea
| | - Jong Ho Lee
- />Department of Optics and Mechatronics Engineering, BK21+ Nano-Integrated Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busandaehak-ro 63beon-gil, Geumjeong-gu, Busan, 609-735 >Korea
| | - Min Jeong Kim
- />Department of Optics and Mechatronics Engineering, BK21+ Nano-Integrated Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busandaehak-ro 63beon-gil, Geumjeong-gu, Busan, 609-735 >Korea
| | - Suck Won Hong
- />Department of Optics and Mechatronics Engineering, BK21+ Nano-Integrated Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busandaehak-ro 63beon-gil, Geumjeong-gu, Busan, 609-735 >Korea
| | - Bongju Kim
- />Clinical Dental Research Institute, Seoul National University Dental Hospital, Seoul, 03080 Korea
| | - Jung Keun Hyun
- />Department of Rehabilitation Medicine, College of Medicine, Cheonan, 330-714 Korea
- />Department of Nanobiomedical Science & BK21+ NBM Global Research Center, Cheonan, 330-714 Korea
- />Institute of Tissue Regeneration Engineering, Dankook University, Cheonan, 330-714 Korea
| | - Yu Suk Choi
- />School of Anatomy, Physiology, and Human Biology, University of Western Australia, Crawley, WA 6009 Australia
| | - Jong-Chul Park
- />Cellbiocontrol Laboratory, Department of Medical Engineering, Yonsei University College of Medicine, 50-1, Yonsei-ro, Seodaemun-gu, Seoul, 120-752 Korea
| | - Dong-Wook Han
- />Department of Optics and Mechatronics Engineering, BK21+ Nano-Integrated Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busandaehak-ro 63beon-gil, Geumjeong-gu, Busan, 609-735 >Korea
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22
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Kelly EA, Russo AS, Jackson CD, Lamantia CE, Majewska AK. Proteolytic regulation of synaptic plasticity in the mouse primary visual cortex: analysis of matrix metalloproteinase 9 deficient mice. Front Cell Neurosci 2015; 9:369. [PMID: 26441540 PMCID: PMC4585116 DOI: 10.3389/fncel.2015.00369] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Accepted: 09/04/2015] [Indexed: 01/16/2023] Open
Abstract
The extracellular matrix (ECM) is known to play important roles in regulating neuronal recovery from injury. The ECM can also impact physiological synaptic plasticity, although this process is less well understood. To understand the impact of the ECM on synaptic function and remodeling in vivo, we examined ECM composition and proteolysis in a well-established model of experience-dependent plasticity in the visual cortex. We describe a rapid change in ECM protein composition during Ocular Dominance Plasticity (ODP) in adolescent mice, and a loss of ECM remodeling in mice that lack the extracellular protease, matrix metalloproteinase-9 (MMP9). Loss of MMP9 also attenuated functional ODP following monocular deprivation (MD) and reduced excitatory synapse density and spine density in sensory cortex. While we observed no change in the morphology of existing dendritic spines, spine dynamics were altered, and MMP9 knock-out (KO) mice showed increased turnover of dendritic spines over a period of 2 days. We also analyzed the effects of MMP9 loss on microglia, as these cells are involved in extracellular remodeling and have been recently shown to be important for synaptic plasticity. MMP9 KO mice exhibited very limited changes in microglial morphology. Ultrastructural analysis, however, showed that the extracellular space surrounding microglia was increased, with concomitant increases in microglial inclusions, suggesting possible changes in microglial function in the absence of MMP9. Taken together, our results show that MMP9 contributes to ECM degradation, synaptic dynamics and sensory-evoked plasticity in the mouse visual cortex.
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Affiliation(s)
- Emily A Kelly
- Center for Visual Science, School of Medicine and Dentistry, Department of Neurobiology and Anatomy, University of Rochester Rochester, NY, USA
| | - Amanda S Russo
- Center for Visual Science, School of Medicine and Dentistry, Department of Neurobiology and Anatomy, University of Rochester Rochester, NY, USA
| | - Cory D Jackson
- Center for Visual Science, School of Medicine and Dentistry, Department of Neurobiology and Anatomy, University of Rochester Rochester, NY, USA
| | - Cassandra E Lamantia
- Center for Visual Science, School of Medicine and Dentistry, Department of Neurobiology and Anatomy, University of Rochester Rochester, NY, USA
| | - Ania K Majewska
- Center for Visual Science, School of Medicine and Dentistry, Department of Neurobiology and Anatomy, University of Rochester Rochester, NY, USA
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23
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Shin YC, Lee JH, Kim MJ, Park JH, Kim SE, Kim JS, Oh JW, Han DW. Biomimetic Hybrid Nanofiber Sheets Composed of RGD Peptide-Decorated PLGA as Cell-Adhesive Substrates. J Funct Biomater 2015; 6:367-78. [PMID: 26034884 PMCID: PMC4493517 DOI: 10.3390/jfb6020367] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Revised: 05/21/2015] [Accepted: 05/28/2015] [Indexed: 11/19/2022] Open
Abstract
In biomedical applications, there is a need for tissue engineering scaffolds to promote and control cellular behaviors, including adhesion, proliferation and differentiation. In particular, the initial adhesion of cells has a great influence on those cellular behaviors. In this study, we concentrate on developing cell-adhesive substrates applicable for tissue engineering scaffolds. The hybrid nanofiber sheets were prepared by electrospinning poly(lactic-co-glycolic acid) (PLGA) and M13 phage, which was genetically modified to enhance cell adhesion thru expressing RGD peptides on their surface. The RGD peptide is a specific motif of extracellular matrix (ECM) for integrin receptors of cells. RGD peptide-decorated PLGA (RGD-PLGA) nanofiber sheets were characterized by scanning electron microscopy, immunofluorescence staining, contact angle measurement and differential scanning calorimetry. In addition, the initial adhesion and proliferation of four different types of mammalian cells were determined in order to evaluate the potential of RGD-PLGA nanofiber sheets as cell-adhesive substrates. Our results showed that the hybrid nanofiber sheets have a three-dimensional porous structure comparable to the native ECM. Furthermore, the initial adhesion and proliferation of cells were significantly enhanced on RGD-PLGA sheets. These results suggest that biomimetic RGD-PLGA nanofiber sheets can be promising cell-adhesive substrates for application as tissue engineering scaffolds.
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Affiliation(s)
- Yong Cheol Shin
- Department of Optics and Mechatronics Engineering, BK21+ Nano-Integrated Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busandaehak-ro 63beon-gil, Geumjeong-gu, Busan 609-735, Korea.
| | - Jong Ho Lee
- Department of Optics and Mechatronics Engineering, BK21+ Nano-Integrated Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busandaehak-ro 63beon-gil, Geumjeong-gu, Busan 609-735, Korea.
| | - Min Jeong Kim
- Department of Optics and Mechatronics Engineering, BK21+ Nano-Integrated Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busandaehak-ro 63beon-gil, Geumjeong-gu, Busan 609-735, Korea.
| | - Ji Hoon Park
- Department of Optics and Mechatronics Engineering, BK21+ Nano-Integrated Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busandaehak-ro 63beon-gil, Geumjeong-gu, Busan 609-735, Korea.
| | - Sung Eun Kim
- Department of Optics and Mechatronics Engineering, BK21+ Nano-Integrated Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busandaehak-ro 63beon-gil, Geumjeong-gu, Busan 609-735, Korea.
| | - Jin Su Kim
- Department of Optics and Mechatronics Engineering, BK21+ Nano-Integrated Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busandaehak-ro 63beon-gil, Geumjeong-gu, Busan 609-735, Korea.
| | - Jin-Woo Oh
- Department of Nanoenergy Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busandaehak-ro 63beon-gil, Geumjeong-gu, Busan 609-735, Korea.
| | - Dong-Wook Han
- Department of Optics and Mechatronics Engineering, BK21+ Nano-Integrated Cogno-Mechatronics Engineering, College of Nanoscience & Nanotechnology, Pusan National University, Busandaehak-ro 63beon-gil, Geumjeong-gu, Busan 609-735, Korea.
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24
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Shin YC, Lee JH, Jin L, Kim MJ, Kim YJ, Hyun JK, Jung TG, Hong SW, Han DW. Stimulated myoblast differentiation on graphene oxide-impregnated PLGA-collagen hybrid fibre matrices. J Nanobiotechnology 2015; 13:21. [PMID: 25886153 PMCID: PMC4379947 DOI: 10.1186/s12951-015-0081-9] [Citation(s) in RCA: 97] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Accepted: 02/26/2015] [Indexed: 02/06/2023] Open
Abstract
Background Electrospinning is a simple and effective method for fabricating micro- and nanofiber matrices. Electrospun fibre matrices have numerous advantages for use as tissue engineering scaffolds, such as high surface area-to-volume ratio, mass production capability and structural similarity to the natural extracellular matrix (ECM). Therefore, electrospun matrices, which are composed of biocompatible polymers and various biomaterials, have been developed as biomimetic scaffolds for the tissue engineering applications. In particular, graphene oxide (GO) has recently been considered as a novel biomaterial for skeletal muscle regeneration because it can promote the growth and differentiation of myoblasts. Therefore, the aim of the present study was to fabricate the hybrid fibre matrices that stimulate myoblasts differentiation for skeletal muscle regeneration. Results Hybrid fibre matrices composed of poly(lactic-co-glycolic acid, PLGA) and collagen (Col) impregnated with GO (GO-PLGA-Col) were successfully fabricated using an electrospinning process. Our results indicated that the GO-PLGA-Col hybrid matrices were comprised of randomly-oriented continuous fibres with a three-dimensional non-woven porous structure. Compositional analysis showed that GO was dispersed uniformly throughout the GO-PLGA-Col matrices. In addition, the hydrophilicity of the fabricated matrices was significantly increased by blending with a small amount of Col and GO. The attachment and proliferation of the C2C12 skeletal myoblasts were significantly enhanced on the GO-PLGA-Col hybrid matrices. Furthermore, the GO-PLGA-Col matrices stimulated the myogenic differentiation of C2C12 skeletal myoblasts, which was enhanced further under the culture conditions of the differentiation media. Conclusions Taking our findings into consideration, it is suggested that the GO-PLGA-Col hybrid fibre matrices can be exploited as potential biomimetic scaffolds for skeletal tissue engineering and regeneration because these GO-impregnated hybrid matrices have potent effects on the induction of spontaneous myogenesis and exhibit superior bioactivity and biocompatibility.
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Affiliation(s)
- Yong Cheol Shin
- Department of Cogno-Mechatronics Engineering & BK21+ Nano-Integrated Cogno-Mechatronics Engineering, Pusan National University, Busan, 609-735, South Korea.
| | - Jong Ho Lee
- Department of Cogno-Mechatronics Engineering & BK21+ Nano-Integrated Cogno-Mechatronics Engineering, Pusan National University, Busan, 609-735, South Korea.
| | - Linhua Jin
- Department of Cogno-Mechatronics Engineering & BK21+ Nano-Integrated Cogno-Mechatronics Engineering, Pusan National University, Busan, 609-735, South Korea.
| | - Min Jeong Kim
- Department of Cogno-Mechatronics Engineering & BK21+ Nano-Integrated Cogno-Mechatronics Engineering, Pusan National University, Busan, 609-735, South Korea.
| | - Yong-Joo Kim
- Department of Biosystems Machinery Engineering, Chungnam National University, Daejeon, 305-764, South Korea.
| | - Jung Keun Hyun
- Department of Rehabilitation Medicine, College of Medicine, Dankook University, Cheonan, 330-714, South Korea. .,Department of Nanobiomedical Science, BK21PLUS NBM Global Research Center, Dankook University, Cheonan, 330-714, South Korea. .,Institute of Tissue Regeneration Engineering, Dankook University, Cheonan, 330-714, South Korea.
| | - Tae-Gon Jung
- Osong Medical Innovation Foundation, Medical Device Development Center, Cheongju, 363-951, South Korea.
| | - Suck Won Hong
- Department of Cogno-Mechatronics Engineering & BK21+ Nano-Integrated Cogno-Mechatronics Engineering, Pusan National University, Busan, 609-735, South Korea.
| | - Dong-Wook Han
- Department of Cogno-Mechatronics Engineering & BK21+ Nano-Integrated Cogno-Mechatronics Engineering, Pusan National University, Busan, 609-735, South Korea.
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25
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Crowe SE, Ellis-Davies GCR. Longitudinal in vivo two-photon fluorescence imaging. J Comp Neurol 2014; 522:1708-27. [PMID: 24214350 DOI: 10.1002/cne.23502] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2013] [Revised: 10/15/2013] [Accepted: 10/15/2013] [Indexed: 12/29/2022]
Abstract
Fluorescence microscopy is an essential technique for the basic sciences, especially biomedical research. Since the invention of laser scanning confocal microscopy in the 1980s, which enabled imaging both fixed and living biological tissue with 3D precision, high-resolution fluorescence imaging has revolutionized biological research. Confocal microscopy, by its very nature, has one fundamental limitation. Due to the confocal pinhole, deep tissue fluorescence imaging is not practical. In contrast (no pun intended), two-photon fluorescence microscopy allows, in principle, the collection of all emitted photons from fluorophores in the imaged voxel, dramatically extending our ability to see deep into living tissue. Since the development of transgenic mice with genetically encoded fluorescent protein in neocortical cells in 2000, two-photon imaging has enabled the dynamics of individual synapses to be followed for up to 2 years. Since the initial landmark contributions to this field in 2002, the technique has been used to understand how neuronal structure are changed by experience, learning, and memory and various diseases. Here we provide a basic summary of the crucial elements that are required for such studies, and discuss many applications of longitudinal two-photon fluorescence microscopy that have appeared since 2002.
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Affiliation(s)
- Sarah E Crowe
- Department of Neuroscience, Mount Sinai School of Medicine, New York, NY, 10029
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26
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Kelly EA, Opanashuk LA, Majewska AK. The effects of postnatal exposure to low-dose bisphenol-A on activity-dependent plasticity in the mouse sensory cortex. Front Neuroanat 2014; 8:117. [PMID: 25374513 PMCID: PMC4205826 DOI: 10.3389/fnana.2014.00117] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Accepted: 10/02/2014] [Indexed: 01/03/2023] Open
Abstract
Bisphenol-A (BPA) is a monomer used in the production of polycarbonate plastics, epoxies and resins and is present in many common household objects ranging from water bottles, can linings, baby bottles, and dental resins. BPA exposure has been linked to numerous negative health effects throughout the body, although the mechanisms of BPA action on the developing brain are still poorly understood. In this study, we sought to investigate whether low dose BPA exposure during a developmental phase when brain connectivity is being organized can cause long-term deleterious effects on brain function and plasticity that outlast the BPA exposure. Lactating dams were orally exposed to 25 μg/kg/day of BPA (one half the U.S. Environmental Protection Agency's 50 μg/kg/day rodent dose reference) or vehicle alone from postnatal day (P)5 to P21. Pups exposed to BPA in their mother's milk exhibited deficits in activity-dependent plasticity in the visual cortex during the visual critical period (P28). To determine the possible mechanisms underlying BPA action, we used immunohistochemistry to examine histological markers known to impact cortical maturity and developmental plasticity and quantified cortical dendritic spine density, morphology, and dynamics. While we saw no changes in parvalbumin neuron density, myelin basic protein expression or microglial density in BPA-exposed animals, we observed increases in spine density on apical dendrites in cortical layer five neurons but no significant alterations in other morphological parameters. Taken together our results suggest that exposure to very low levels of BPA during a critical period of brain development can have profound consequences for the normal wiring of sensory circuits and their plasticity later in life.
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Affiliation(s)
- Emily A Kelly
- Department of Neurobiology and Anatomy, Center for Visual Science, School of Medicine and Dentistry, University of Rochester Rochester, NY, USA
| | - Lisa A Opanashuk
- Department of Environmental Medicine, University of Rochester Rochester, NY, USA
| | - Ania K Majewska
- Department of Neurobiology and Anatomy, Center for Visual Science, School of Medicine and Dentistry, University of Rochester Rochester, NY, USA
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27
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Rosenegger DG, Tran CHT, LeDue J, Zhou N, Gordon GR. A high performance, cost-effective, open-source microscope for scanning two-photon microscopy that is modular and readily adaptable. PLoS One 2014; 9:e110475. [PMID: 25333934 PMCID: PMC4204885 DOI: 10.1371/journal.pone.0110475] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Accepted: 08/28/2014] [Indexed: 11/17/2022] Open
Abstract
Two-photon laser scanning microscopy has revolutionized the ability to delineate cellular and physiological function in acutely isolated tissue and in vivo. However, there exist barriers for many laboratories to acquire two-photon microscopes. Additionally, if owned, typical systems are difficult to modify to rapidly evolving methodologies. A potential solution to these problems is to enable scientists to build their own high-performance and adaptable system by overcoming a resource insufficiency. Here we present a detailed hardware resource and protocol for building an upright, highly modular and adaptable two-photon laser scanning fluorescence microscope that can be used for in vitro or in vivo applications. The microscope is comprised of high-end componentry on a skeleton of off-the-shelf compatible opto-mechanical parts. The dedicated design enabled imaging depths close to 1 mm into mouse brain tissue and a signal-to-noise ratio that exceeded all commercial two-photon systems tested. In addition to a detailed parts list, instructions for assembly, testing and troubleshooting, our plan includes complete three dimensional computer models that greatly reduce the knowledge base required for the non-expert user. This open-source resource lowers barriers in order to equip more laboratories with high-performance two-photon imaging and to help progress our understanding of the cellular and physiological function of living systems.
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Affiliation(s)
- David G Rosenegger
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Hotchkiss Brain Institute, Calgary, Alberta, Canada
| | - Cam Ha T Tran
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Hotchkiss Brain Institute, Calgary, Alberta, Canada
| | - Jeffery LeDue
- Department of Psychiatry, University of British Columbia, Brain Research Centre, Vancouver, British Columbia, Canada
| | - Ning Zhou
- Graduate Institute of Clinical Medical Science, China Medical University, Translational Medicine Research Center, Taichung, Taiwan
| | - Grant R Gordon
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Hotchkiss Brain Institute, Calgary, Alberta, Canada
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28
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Optimized temporally deconvolved Ca²⁺ imaging allows identification of spatiotemporal activity patterns of CA1 hippocampal ensembles. Neuroimage 2014; 94:239-249. [PMID: 24650598 DOI: 10.1016/j.neuroimage.2014.03.030] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Revised: 02/07/2014] [Accepted: 03/10/2014] [Indexed: 01/30/2023] Open
Abstract
Hippocampal activity is characterized by the coordinated firing of a subset of neurons. Such neuronal ensembles can either be driven by external stimuli to form new memory traces or be reactivated by intrinsic mechanisms to reactivate and consolidate old memories. Hippocampal network oscillations orchestrate this coherent activity. One key question is how the topology, i.e. the functional connectivity of neuronal networks supports their desired function. Recently, this has been addressed by characterizing the intrinsic properties for the highly recurrently connected CA3 region using organotypic slice cultures and Ca(2+) imaging. In the present study, we aimed to determine the properties of CA1 hippocampal ensembles at high temporal and multiple single cell resolution. Thus, we performed Ca(2+) imaging using the chemical fluorescent Ca(2+) indicator Oregon Green BAPTA 1-AM. To achieve most physiological conditions, we used acute hippocampal slices that were recorded in a so-called interface chamber. To faithfully reconstruct firing patterns of multiple neurons in the field of view, we optimized deconvolution-based detection of action potential associated Ca(2+) events. Our approach outperformed currently available detection algorithms by its sensitivity and robustness. In combination with advanced network analysis, we found that acute hippocampal slices contain a median of 11 CA1 neuronal ensembles with a median size of 4 neurons. This apparently low number of neurons is likely due to the confocal imaging acquisition and therefore yields a lower limit. The distribution of ensemble sizes was compatible with a scale-free topology, as far as can be judged from data with small cell numbers. Interestingly, cells were more tightly clustered in large ensembles than in smaller groups. Together, our data show that spatiotemporal activity patterns of hippocampal neuronal ensembles can be reliably detected with deconvolution-based imaging techniques in mouse hippocampal slices. The here presented techniques are fully applicable to similar studies of distributed optical measurements of neuronal activity (in vivo), where signal-to-noise ratio is critical.
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29
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Shih AY, Nishimura N, Nguyen J, Friedman B, Lyden PD, Schaffer CB, Kleinfeld D. Optically induced occlusion of single blood vessels in rodent neocortex. Cold Spring Harb Protoc 2013; 2013:1153-60. [PMID: 24298038 DOI: 10.1101/pdb.prot079509] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The ability to form targeted vascular occlusions in small vessels of the brain is an important technique for studying the microscopic basis of cerebral ischemia. We describe two complementary methods that enable targeted occlusion of any single blood vessel within the upper 500 µm of adult rodent neocortex. Our goal is to generate highly localized regions of ischemia by blocking penetrating arterioles and ascending venules, which are bottlenecks of flow in the cortical angioarchitecture. One method, termed photothrombosis, makes use of linear optical absorption by a photosensitizer, transiently circulated in the blood stream, to induce a clot in a surface or near-surface segment of a vessel. The second method, termed plasma-mediated ablation, makes use of nonlinear optical interactions, without the need to introduce an exogenous absorber, to induce clots in subsurface segments of penetrating vessels, as well as subsurface microvessels and capillaries. The choice of the method for occlusion of individual vessels depends on the location of the vessels being studied and the objectives of the study. Here we describe concurrent high resolution in vivo imaging and auxiliary laser setups, occlusion protocols, and post hoc histological procedures.
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30
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Response selectivity is correlated to dendritic structure in parvalbumin-expressing inhibitory neurons in visual cortex. J Neurosci 2013; 33:11724-33. [PMID: 23843539 DOI: 10.1523/jneurosci.2196-12.2013] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Inhibitory neurons have been shown to perform a variety of functions within brain circuits, including shaping response functions in target cells. Still, how the properties of specific inhibitory neuron classes relate to their local circuits remains unclear. To better understand the distribution and origins of orientation selectivity in inhibitory neurons expressing the calcium binding protein parvalbumin (PV) in the mouse primary visual cortex, we labeled PV(+) neurons with red fluorescent protein (RFP) and targeted them for cell-attached electrophysiological recordings. PV(+) neurons could be broadly tuned or sharply tuned for orientation but tended to be more broadly tuned than unlabeled neurons on average. The dendritic morphology of PV(+) cells, revealed by intracellular labeling, was strongly correlated with tuning: highly tuned PV(+) neurons had shorter dendrites that branched nearer to the soma and had smaller dendritic fields overall, whereas broadly tuned PV(+) neurons had longer dendrites that branched farther from the soma, producing larger dendritic fields. High-speed two-photon calcium imaging of visual responses showed that the orientation preferences of highly tuned PV(+) neurons resembled the preferred orientations of neighboring cells. These results suggest that the diversity of the local neighborhood and the nature of dendritic sampling may both contribute to the response selectivity of PV(+) neurons.
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31
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Marker DF, Tremblay MÈ, Puccini JM, Barbieri J, Gantz Marker MA, Loweth CJ, Muly EC, Lu SM, Goodfellow VS, Dewhurst S, Gelbard HA. The new small-molecule mixed-lineage kinase 3 inhibitor URMC-099 is neuroprotective and anti-inflammatory in models of human immunodeficiency virus-associated neurocognitive disorders. J Neurosci 2013; 33:9998-10010. [PMID: 23761895 PMCID: PMC3682381 DOI: 10.1523/jneurosci.0598-13.2013] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Revised: 04/09/2013] [Accepted: 05/06/2013] [Indexed: 01/11/2023] Open
Abstract
Human immunodeficiency virus (HIV)-associated neurocognitive disorders (HAND) is a significant source of disability in the HIV-infected population. Even with stringent adherence to anti-retroviral therapy, >50% of patients living with HIV-1 will develop HAND (Heaton et al., 2010). Because suppression of viral replication alone is not enough to stop HAND progression, there is a need for an adjunctive neuroprotective therapy in this population. To this end, we have developed a small-molecule brain-penetrant inhibitor with activity against mixed-lineage kinase 3 (MLK3), named URMC-099. MLK3 activation is associated with many of the pathologic hallmarks of HAND (Bodner et al., 2002, 2004; Sui et al., 2006) and therefore represents a prime target for adjunctive therapy based on small-molecule kinase inhibition. Here we demonstrate the anti-inflammatory and neuroprotective effects of URMC-099 in multiple murine and rodent models of HAND. In vitro, URMC-099 treatment reduced inflammatory cytokine production by HIV-1 Tat-exposed microglia and prevented destruction and phagocytosis of cultured neuronal axons by these cells. In vivo, URMC-099 treatment reduced inflammatory cytokine production, protected neuronal architecture, and altered the morphologic and ultrastructural response of microglia to HIV-1 Tat exposure. In conclusion, these data provide compelling in vitro and in vivo evidence to investigate the utility of URMC-099 in other models of HAND with the goal of advancement to an adjunctive therapeutic agent.
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MESH Headings
- Animals
- Bone Marrow Transplantation
- CX3C Chemokine Receptor 1
- Cell Line, Transformed/drug effects
- Cell Line, Transformed/virology
- Cells, Cultured
- Cytokines
- Disease Models, Animal
- Embryo, Mammalian
- Gene Products, tat/immunology
- Green Fluorescent Proteins/genetics
- Green Fluorescent Proteins/metabolism
- HIV Infections/complications
- HIV Infections/drug therapy
- HIV Infections/virology
- HIV-1/physiology
- Hippocampus/pathology
- Humans
- Inflammation/genetics
- Inflammation/pathology
- Inflammation/prevention & control
- Inflammation/virology
- MAP Kinase Kinase Kinases/antagonists & inhibitors
- Mice
- Mice, Transgenic
- Microscopy, Immunoelectron
- Neuroprotective Agents/therapeutic use
- Phagocytosis/drug effects
- Phagocytosis/genetics
- Phosphorylation/drug effects
- Pyridines/pharmacology
- Pyridines/therapeutic use
- Pyrroles/pharmacology
- Pyrroles/therapeutic use
- Rats
- Receptors, Chemokine/genetics
- Receptors, Chemokine/metabolism
- Signal Transduction/drug effects
- Signal Transduction/genetics
- Statistics, Nonparametric
- Time Factors
- Transfection
- tat Gene Products, Human Immunodeficiency Virus
- Mitogen-Activated Protein Kinase Kinase Kinase 11
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Affiliation(s)
- Daniel F Marker
- Centers for Neural Development and Disease, University of Rochester, Rochester, New York 14642, USA.
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32
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Nikolenko V, Yuste R. How to build a two-photon microscope with a confocal scan head. Cold Spring Harb Protoc 2013; 2013:588-92. [PMID: 23734024 DOI: 10.1101/pdb.ip075135] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
This article provides practical guidelines for the conversion of a standard confocal microscope into a two-photon microscope. This conversion enables the investigator to have access to two-photon microscopy without the large budget necessary to purchase a commercial instrument. Two-photon fluorescence microscopy allows deep-tissue imaging in highly scattering preparations and long-term imaging of live tissue without the photodamage that is caused by out-of-focus light. It is, therefore, an essential tool for imaging cells under physiologically relevant conditions such as acute or cultured brain slices or in vivo.
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33
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Dunn KW, Sutton TA, Sandoval RM. Live-animal imaging of renal function by multiphoton microscopy. ACTA ACUST UNITED AC 2013; Chapter 12:Unit12.9. [PMID: 23042524 DOI: 10.1002/0471142956.cy1209s62] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Intravital microscopy, microscopy of living animals, is a powerful research technique that combines the resolution and sensitivity found in microscopic studies of cultured cells with the relevance and systemic influences of cells in the context of the intact animal. The power of intravital microscopy has recently been extended with the development of multiphoton fluorescence microscopy systems capable of collecting optical sections from deep within the kidney at subcellular resolution, supporting high-resolution characterizations of the structure and function of glomeruli, tubules, and vasculature in the living kidney. Fluorescent probes are administered to an anesthetized, surgically prepared animal, followed by image acquisition for up to 3 hr. Images are transferred via a high-speed network to specialized computer systems for digital image analysis. This general approach can be used with different combinations of fluorescent probes to evaluate processes such as glomerular permeability, proximal tubule endocytosis, microvascular flow, vascular permeability, mitochondrial function, and cellular apoptosis/necrosis.
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Affiliation(s)
- Kenneth W Dunn
- Indiana University School of Medicine, Indianapolis, IN, USA
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34
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Podgorski K, Haas K. Fast non-negative temporal deconvolution for laser scanning microscopy. JOURNAL OF BIOPHOTONICS 2013; 6:153-162. [PMID: 22438321 DOI: 10.1002/jbio.201100133] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2011] [Revised: 02/27/2012] [Accepted: 02/28/2012] [Indexed: 05/31/2023]
Abstract
Laser scanning microscopy (LSM) is a common technique for high resolution fluorescent imaging. Here we describe a fast algorithm for non-negative deconvolution and apply it to readout of LSM detector photocurrents. By broadening photon impulses and deconvolving sampled photocurrent, effective quantum efficiency of the imaging system is increased. Using simulation and imaging with a custom-built two-photon microscope, we demonstrate improved fidelity of images acquired at short dwell times over a wide range of photon rates. Images formed show increased correlation-to-sample equivalent to a 25% increase in photon rate, lower noise, and reduced bleed-through compared to conventional image generation.
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Affiliation(s)
- Kaspar Podgorski
- Department of Cellular and Physiological Sciences and the Brain Research Centre, University of British Columbia, 2211 Wesbrook Mall, Vancouver, BC, V6T2B5, Canada
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35
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Abstract
In vivo imaging with two-photon microscopy is becoming an indispensable technique to investigate cellular and subcellular phenomenon in living tissues including the central nervous system. This microscopy enables to image dynamics of molecules, morphology, and excitability with minimal invasion to tissues. Microglia are residual immune-responsive cells in the central nervous system and show highly dynamic response to the environmental alterations. Diverse roles of microglial functions in the intact and pathological brain are still largely unknown. In this chapter we describe the detailed method to image the dynamics of microglia in the mouse brain in vivo.
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36
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Weimer RM, Hill TC, Hamilton AM, Zito K. Imaging synaptic protein dynamics using photoactivatable green fluorescent protein. Cold Spring Harb Protoc 2012; 2012:771-777. [PMID: 22753605 DOI: 10.1101/pdb.prot070029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Considerable evidence has accumulated that structural changes in dendritic spines and their synapses are associated with adaptive functional changes in cortical circuits, such as during circuit refinement in young animals and in learning and memory in adults. Understanding the mechanisms of circuit plasticity requires detailed investigation of the structural dynamics of dendritic spines and how they are regulated by neural activity and sensory experience. Studying the dynamic localization of synaptic proteins in dendritic spines and how their stabilization and exchange rates influence spine structural plasticity is also important. This protocol describes imaging approaches to study synaptic protein dynamics in dendritic spines of the rodent cerebral cortex. It gives a strategy for generating photoactivatable green fluorescent protein (PA-GFP)-tagged synaptic proteins and in vitro and in vivo transfection methods for coexpression of these proteins with a spectrally separable cell-filling marker (DsRed-Express). Methods for tracking synaptic protein localization using photoactivation and time-lapse imaging of PA-GFP in spiny pyramidal neuron dendrites are given. A discussion of imaging hardware and software preferences is also included. The methods described here can be used to study the dynamic processes underlying spine synapse development during the formation and plasticity of neural circuits in the mammalian brain.
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37
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Kovalchuk Y, Garaschuk O. Two-photon chloride imaging using MQAE in vitro and in vivo. Cold Spring Harb Protoc 2012; 2012:778-85. [PMID: 22753606 DOI: 10.1101/pdb.prot070037] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
This protocol describes a technique for high-resolution chloride imaging of living cells using a quinoline-based chloride (Cl(-)) indicator dye, MQAE (N-[6-methoxyquinolyl] acetoethyl ester). Bath-applied to acute brain slices, MQAE provides high-quality labeling of neuronal cells and their processes. In living anesthetized mice, cortical cells are labeled using the multicell bolus loading procedure. In combination with two-photon microscopy, this procedure enables in vivo visualization of cell bodies of neurons and astrocytes as well as some astrocytic processes and allows one to monitor changes in the intracellular chloride concentration in dozens of individual cells.
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38
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Hirase H, Nikolenko V, Yuste R. Multiphoton stimulation of neurons and spines. Cold Spring Harb Protoc 2012; 2012:472-5. [PMID: 22474661 DOI: 10.1101/pdb.prot068569] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
This protocol describes an optical method to directly stimulate a neuron (i.e., without using any caged chemicals or genetic probes) using an infrared ultrafast mode-locked laser. This method can trigger action potentials in a targeted neuron when a laser beam is applied to the somatic membrane. Alternatively, it can mimic excitatory postsynaptic potentials (EPSPs) when applied to dendritic spines. The protocol has been applied successfully using juvenile (postnatal day 7-14) C57 mouse neocortical and hippocampal acute slices (∼300-µm thickness). It can be used in conjunction with slices bulk loaded with calcium indicators, such as Fura-2 AM.
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39
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Maschio MD, Beltramo R, De Stasi AM, Fellin T. Two-Photon Calcium Imaging in the Intact Brain. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 740:83-102. [DOI: 10.1007/978-94-007-2888-2_4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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40
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Choong FX, Sandoval RM, Molitoris BA, Richter-Dahlfors A. Multiphoton microscopy applied for real-time intravital imaging of bacterial infections in vivo. Methods Enzymol 2012; 506:35-61. [PMID: 22341218 PMCID: PMC4136485 DOI: 10.1016/b978-0-12-391856-7.00027-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
To understand the underlying mechanisms of bacterial infections, researchers have for long addressed the molecular interactions occurring when the bacterium interacts with host target cells. In these studies, primarily based on in vitro systems, molecular details have been revealed along with increased knowledge regarding the general infection process. With the recent advancements in in vivo imaging techniques, we are now in a position to bridge a transition from classical minimalistic in vitro approaches to allow infections to be studied in its native complexity-the live organ. Techniques such as multiphoton microscopy (MPM) allow cellular-level visualization of the dynamic infection process in real time within the living host. Studies in which all interplaying factors, such as the influences of the immune, lymphatic, and vascular systems can be accounted for, are likely to provide new insights to our current understanding of the infection process. MPM imaging becomes extra powerful when combined with advanced surgical procedure, allowing studies of the illusive early hours of infection. In this chapter, our intention is to provide a general view on how to design and carry out intravital imaging of a bacterial infection. While exemplifying this using a spatiotemporally well-controlled uropathogenic Escherichia coli (UPEC) infection in rat kidneys, we hope to provide the reader with general considerations that can be adapted to other bacterial infections in organs other than the kidney.
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Affiliation(s)
- Ferdinand X Choong
- Department of Neuroscience, Swedish Medical Nanoscience Center, Karolinska Institutet, Stockholm, Sweden
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41
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Eichhoff G, Garaschuk O. Two-photon imaging of neural networks in a mouse model of Alzheimer's disease. Cold Spring Harb Protoc 2011; 2011:1206-1216. [PMID: 21969618 DOI: 10.1101/pdb.prot065789] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
In humans, Alzheimer's disease (AD) develops over many years. It comprises a chain of subtle yet irreversible alterations in brain function, finally leading to impairment of memory and cognition. Presymptomatic and thus invisible in humans, these alterations can be studied in the animal models of AD. Mouse models of the disease expressing AD-related proteins with familial mutations reproduce several pathological hallmarks of AD. Although the models do not recapitulate the abundant neuronal loss seen in humans, they offer a unique opportunity to learn more about synaptic and cellular mechanisms underlying the disease (both in their essence and in their temporal sequence) through in vivo analyses of brain function. This, however, requires in vivo monitoring of brain function in aged living animals at both a single-cell and network level. Tools developed over the last several decades can be used to selectively mark and to visualize in vivo many important elements of the diseased brain parenchyma, such as amyloid plaques, individual neurons, and glial and microglial cells. Here we describe a method in which cell-type-specific labeling of neurons and glia is combined with in vivo two-photon calcium imaging and fluorescent labeling of amyloid plaques to study functional properties of cortical circuits in a mouse model of AD.
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42
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Entenberg D, Wyckoff J, Gligorijevic B, Roussos ET, Verkhusha VV, Pollard JW, Condeelis J. Setup and use of a two-laser multiphoton microscope for multichannel intravital fluorescence imaging. Nat Protoc 2011; 6:1500-20. [PMID: 21959234 DOI: 10.1038/nprot.2011.376] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Characterizing biological mechanisms dependent upon the interaction of many cell types in vivo requires both multiphoton microscope systems capable of expanding the number and types of fluorophores that can be imaged simultaneously while removing the wavelength and tunability restrictions of existing systems, and enhanced software for extracting critical cellular parameters from voluminous 4D data sets. We present a procedure for constructing a two-laser multiphoton microscope that extends the wavelength range of excitation light, expands the number of simultaneously usable fluorophores and markedly increases signal to noise via 'over-clocking' of detection. We also utilize a custom-written software plug-in that simplifies the quantitative tracking and analysis of 4D intravital image data. We begin by describing the optics, hardware, electronics and software required, and finally the use of the plug-in for analysis. We demonstrate the use of the setup and plug-in by presenting data collected via intravital imaging of a mouse model of breast cancer. The procedure may be completed in ∼24 h.
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Affiliation(s)
- David Entenberg
- Department of Anatomy and Structural Biology, and Gruss Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, New York, USA
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43
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Two-photon in vivo imaging of cells. Pediatr Nephrol 2011; 26:1483-9. [PMID: 21404099 DOI: 10.1007/s00467-011-1818-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2010] [Revised: 01/11/2011] [Accepted: 01/25/2011] [Indexed: 01/05/2023]
Abstract
In vivo imaging of cells gives a glimpse into the world of biology in a natural setting unparalleled by any other venue. Two-photon imaging of fluorescently labeled cells has become the standard to obtain high-resolution, dynamic images of living specimens with great specificity. This review focuses on providing the reader with a short history of, and impetus behind, two-photon imaging, its working mechanics, and emerging technologies related to biological multiphoton imaging.
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44
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Malik WQ, Schummers J, Sur M, Brown EN. Denoising two-photon calcium imaging data. PLoS One 2011; 6:e20490. [PMID: 21687727 PMCID: PMC3110192 DOI: 10.1371/journal.pone.0020490] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2011] [Accepted: 04/27/2011] [Indexed: 11/18/2022] Open
Abstract
Two-photon calcium imaging is now an important tool for in vivo imaging of biological systems. By enabling neuronal population imaging with subcellular resolution, this modality offers an approach for gaining a fundamental understanding of brain anatomy and physiology. Proper analysis of calcium imaging data requires denoising, that is separating the signal from complex physiological noise. To analyze two-photon brain imaging data, we present a signal plus colored noise model in which the signal is represented as harmonic regression and the correlated noise is represented as an order autoregressive process. We provide an efficient cyclic descent algorithm to compute approximate maximum likelihood parameter estimates by combing a weighted least-squares procedure with the Burg algorithm. We use Akaike information criterion to guide selection of the harmonic regression and the autoregressive model orders. Our flexible yet parsimonious modeling approach reliably separates stimulus-evoked fluorescence response from background activity and noise, assesses goodness of fit, and estimates confidence intervals and signal-to-noise ratio. This refined separation leads to appreciably enhanced image contrast for individual cells including clear delineation of subcellular details and network activity. The application of our approach to in vivo imaging data recorded in the ferret primary visual cortex demonstrates that our method yields substantially denoised signal estimates. We also provide a general Volterra series framework for deriving this and other signal plus correlated noise models for imaging. This approach to analyzing two-photon calcium imaging data may be readily adapted to other computational biology problems which apply correlated noise models.
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Affiliation(s)
- Wasim Q Malik
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, United States of America.
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45
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Near-infrared branding efficiently correlates light and electron microscopy. Nat Methods 2011; 8:568-70. [PMID: 21642966 DOI: 10.1038/nmeth.1622] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2011] [Accepted: 04/22/2011] [Indexed: 11/08/2022]
Abstract
The correlation of light and electron microscopy of complex tissues remains a major challenge. Here we report near-infrared branding (NIRB), which facilitates such correlation by using a pulsed, near-infrared laser to create defined fiducial marks in three dimensions in fixed tissue. As these marks are fluorescent and can be photo-oxidized to generate electron contrast, they can guide re-identification of previously imaged structures as small as dendritic spines by electron microscopy.
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46
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Abstract
Multi-photon microscopy, now in its twentieth year, has developed into one of the most robust and powerful techniques for live cell and in vivo fluorescence imaging. Although its theoretical framework is nearly a century old, it has only become a practical tool for biological research with the development of ultrafast lasers and scanning microscopy techniques. In this unit, we outline the basic principles of multi-photon microscopy, paying special attention to technical considerations for biological applications. Furthermore, we discuss some common applications of the technique, mainly in the field of live cell and in vivo imaging. We illustrate how multi-photon microscopy can be utilized to address questions ranging from structural cell changes to trafficking of membrane proteins in living organisms, often with resolutions of hundreds of milliseconds. We conclude by outlining the necessary elements needed to establish a successful two-photon microscopy system.
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Affiliation(s)
- Krishnan Padmanabhan
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA
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47
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Zheng HW, Malik WQ, Runyan CA, Sur M, Brown EN. Modeling two-photon calcium fluorescence of episodic V1 recordings using multifrequency analysis. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2011; 2011:3016-3019. [PMID: 22254975 PMCID: PMC4374803 DOI: 10.1109/iembs.2011.6090826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The use of two-photon microscopy allows for imaging of deep neural tissue in vivo. This paper examines frequency-based analysis to two-photon calcium fluorescence images with the goal of deriving smooth tuning curves. We present a multifrequency analysis approach for improved extraction of calcium responses in episodic stimulation experiments, that is, when the stimulus is applied for a number of frames, then turned off for the next few frames, and so on. Episodic orientation stimulus was applied while recording from the primary visual cortex of an anesthetized mouse. The multifrequency model demonstrated improved tuning curve descriptions of the neurons. It also offers perspective regarding the characteristics of calcium fluorescence imaging of the brain.
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Affiliation(s)
| | - Wasim Q. Malik
- Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114. He is also with the Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139
| | - Caroline A. Runyan
- the Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139
| | - Mriganka Sur
- the Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139
| | - Emery N. Brown
- the Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114. He is also with the Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139
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48
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Tremblay MÈ, Lowery RL, Majewska AK. Microglial interactions with synapses are modulated by visual experience. PLoS Biol 2010; 8:e1000527. [PMID: 21072242 PMCID: PMC2970556 DOI: 10.1371/journal.pbio.1000527] [Citation(s) in RCA: 1061] [Impact Index Per Article: 75.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2010] [Accepted: 09/09/2010] [Indexed: 11/29/2022] Open
Abstract
Microglia, the brain's immune cells, show unique interactions with nearby synaptic elements under non-pathological conditions that are sensitive to changes in sensory experience. Microglia are the immune cells of the brain. In the absence of pathological insult, their highly motile processes continually survey the brain parenchyma and transiently contact synaptic elements. Aside from monitoring, their physiological roles at synapses are not known. To gain insight into possible roles of microglia in the modification of synaptic structures, we used immunocytochemical electron microscopy, serial section electron microscopy with three-dimensional reconstructions, and two-photon in vivo imaging to characterize microglial interactions with synapses during normal and altered sensory experience, in the visual cortex of juvenile mice. During normal visual experience, most microglial processes displayed direct apposition with multiple synapse-associated elements, including synaptic clefts. Microglial processes were also distinctively surrounded by pockets of extracellular space. In terms of dynamics, microglial processes localized to the vicinity of small and transiently growing dendritic spines, which were typically lost over 2 d. When experience was manipulated through light deprivation and reexposure, microglial processes changed their morphology, showed altered distributions of extracellular space, displayed phagocytic structures, apposed synaptic clefts more frequently, and enveloped synapse-associated elements more extensively. While light deprivation induced microglia to become less motile and changed their preference of localization to the vicinity of a subset of larger dendritic spines that persistently shrank, light reexposure reversed these behaviors. Taken together, these findings reveal different modalities of microglial interactions with synapses that are subtly altered by sensory experience. These findings suggest that microglia may actively contribute to the experience-dependent modification or elimination of a specific subset of synapses in the healthy brain. Microglia are important players in immune responses to brain injury. In the event of pathological insults, microglia rapidly become activated and acquire the ability to release various inflammatory molecules that influence neuronal survival as well as synaptic function and plasticity. Similarly to macrophages in other areas of the body, activated microglia can engulf, or phagocytose, cellular debris and are believed to eliminate synapses. In the absence of pathological insult, microglia are more quiescent, but still, these immune surveillants continually sample their surrounding environment and contact neighboring cells and synapses. To further explore the roles of microglia at synapses under non-pathological conditions, we used quantitative electron microscopy and two-photon in vivo imaging to characterize the interactions between quiescent microglia and synaptic elements in the visual cortex of juvenile mice. We also examined the “activity-dependent” processes involved by preventing light exposure in a group of mice. We show surprising changes in microglial behavior during alterations in visual experience, such as increased phagocytosis of synaptic elements and interaction with subsets of structurally dynamic and transient synapses. These observations suggest that microglia may participate in the modification or elimination of synaptic structures, and therefore actively contribute to learning and memory in the healthy brain.
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Affiliation(s)
- Marie-Ève Tremblay
- Department of Neurobiology and Anatomy and Center for Visual Science, University of Rochester, Rochester, New York, United States of America
- * E-mail: (MÈT); (AKM)
| | - Rebecca L. Lowery
- Department of Neurobiology and Anatomy and Center for Visual Science, University of Rochester, Rochester, New York, United States of America
| | - Ania K. Majewska
- Department of Neurobiology and Anatomy and Center for Visual Science, University of Rochester, Rochester, New York, United States of America
- * E-mail: (MÈT); (AKM)
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49
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P/Q and N channels control baseline and spike-triggered calcium levels in neocortical axons and synaptic boutons. J Neurosci 2010; 30:11858-69. [PMID: 20810905 DOI: 10.1523/jneurosci.2651-10.2010] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Cortical axons contain a diverse range of voltage-activated ion channels, including Ca(2+) currents. Interestingly, Ca(2+) channels are not only located at presynaptic terminals, but also in the axon initial segment (AIS), suggesting a potentially important role in the regulation of action potential generation and neuronal excitability. Here, using two-photon microscopy and whole-cell patch-clamp recording, we examined the properties and role of calcium channels located in the AIS and presynaptic terminals of ferret layer 5 prefrontal cortical pyramidal cells in vitro. Subthreshold depolarization of the soma resulted in an increase in baseline and spike-triggered calcium concentration in both the AIS and nearby synaptic terminals. The increase in baseline calcium concentration rose with depolarization and fell with hyperpolarization with a time constant of approximately 1 s and was blocked by removal of Ca(2+) from the bathing medium. The increases in calcium concentration at the AIS evoked by subthreshold or suprathreshold depolarization of the soma were blocked by the P/Q-channel antagonist omega-agatoxin IVA or the N-channel antagonist omega-conotoxin GVIA or both. The presence of these channels in the AIS pyramidal cells was confirmed with immunochemistry. Block of these channels slowed axonal action potential repolarization, apparently from reduction of the activation of a Ca(2+)-activated K(+) current, and increased neuronal excitability. These results demonstrate novel mechanisms by which calcium currents may control the electrophysiological properties of axonal spike generation and neurotransmitter release in the neocortex.
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50
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Marker DF, Tremblay ME, Lu SM, Majewska AK, Gelbard HA. A thin-skull window technique for chronic two-photon in vivo imaging of murine microglia in models of neuroinflammation. J Vis Exp 2010:2059. [PMID: 20972389 PMCID: PMC3216629 DOI: 10.3791/2059] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Traditionally in neuroscience, in vivo two photon imaging of the murine central nervous system has either involved the use of open-skull or thinned-skull preparations. While the open-skull technique is very versatile, it is not optimal for studying microglia because it is invasive and can cause microglial activation. Even though the thinned-skull approach is minimally invasive, the repeated re-thinning of skull required for chronic imaging increases the risks of tissue injury and microglial activation and allows for a limited number of imaging sessions. Here we present a chronic thin-skull window method for monitoring murine microglia in vivo over an extended period of time using two-photon microscopy. We demonstrate how to prepare a stable, accessible, thinned-skull cortical window (TSCW) with an apposed glass coverslip that remains translucent over the course of three weeks of intermittent observation. This TSCW preparation is far more immunologically inert with respect to microglial activation than open craniotomy or repeated skull thinning and allows an arbitrary number of imaging sessions during a time period of weeks. We prepare TSCW in CX₃CR₁ GFP/+ mice to visualize microglia with enhanced green fluorescent protein to ≤150 μm beneath the pial surface. We also show that this preparation can be used in conjunction with stereotactic brain injections of the HIV-1 neurotoxic protein Tat, adjacent to the TSCW, which is capable of inducing durable microgliosis. Therefore, this method is extremely useful for examining changes in microglial morphology and motility over time in the living brain in models of HIV Associated Neurocognitive Disorder (HAND) and other neurodegenerative diseases with a neuroinflammatory component.
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Affiliation(s)
- Daniel F Marker
- Center for Neural Development and Disease, Department of Neurology, Child Neurology Division, University of Rochester, USA
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