1
|
Xue Y, Boivin JR, Wadduwage DN, Park JK, Nedivi E, So PTC. Multiline orthogonal scanning temporal focusing (mosTF) microscopy for scattering reduction in in vivo brain imaging. Sci Rep 2024; 14:10954. [PMID: 38740797 PMCID: PMC11091065 DOI: 10.1038/s41598-024-57208-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Accepted: 03/15/2024] [Indexed: 05/16/2024] Open
Abstract
Temporal focusing two-photon microscopy has been utilized for high-resolution imaging of neuronal and synaptic structures across volumes spanning hundreds of microns in vivo. However, a limitation of temporal focusing is the rapid degradation of the signal-to-background ratio and resolution with increasing imaging depth. This degradation is due to scattered emission photons being widely distributed, resulting in a strong background. To overcome this challenge, we have developed multiline orthogonal scanning temporal focusing (mosTF) microscopy. mosTF captures a sequence of images at each scan location of the excitation line. A reconstruction algorithm then reassigns scattered photons back to their correct scan positions. We demonstrate the effectiveness of mosTF by acquiring neuronal images of mice in vivo. Our results show remarkable improvements in in vivo brain imaging with mosTF, while maintaining its speed advantage.
Collapse
Affiliation(s)
- Yi Xue
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Laser Biomedical Research Center, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Department of Biomedical Engineering, University of California, Davis, CA, 95616, USA
| | - Josiah R Boivin
- Picower Institute, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Dushan N Wadduwage
- Laser Biomedical Research Center, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Center for Advanced Imaging, Faculty of Arts and Sciences, Harvard University, Cambridge, MA, 02138, USA
| | - Jong Kang Park
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Elly Nedivi
- Picower Institute, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Peter T C So
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
- Laser Biomedical Research Center, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
| |
Collapse
|
2
|
Camli B, Andrus L, Roy A, Mishra B, Xu C, Georgakoudi I, Tkaczyk T, Ben-Yakar A. Two photon imaging probe with highly efficient autofluorescence collection at high scattering and deep imaging conditions. BIOMEDICAL OPTICS EXPRESS 2024; 15:3163-3182. [PMID: 38855663 PMCID: PMC11161376 DOI: 10.1364/boe.520729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Revised: 04/05/2024] [Accepted: 04/06/2024] [Indexed: 06/11/2024]
Abstract
In this paper, we present a 2-photon imaging probe system featuring a novel fluorescence collection method with improved and reliable efficiency. The system aims to miniaturize the potential of 2-photon imaging in the metabolic and morphological characterization of cervical tissue at sub-micron resolution over large imaging depths into a flexible and clinically viable platform towards the early detection of cancers. Clinical implementation of such a probe system is challenging due to inherently low levels of autofluorescence, particularly when imaging deep in highly scattering tissues. For an efficient collection of fluorescence signals, our probe employs 12 0.5 NA collection fibers arranged around a miniaturized excitation objective. By bending and terminating a multitude of collection fibers at a specific angle, we increase collection area and directivity significantly. Positioning of these fibers allows the collection of fluorescence photons scattered away from their ballistic trajectory multiple times, which offers a system collection efficiency of 4%, which is 55% of what our bench-top microscope with 0.75 NA objective achieves. We demonstrate that the collection efficiency is largely maintained even at high scattering conditions and high imaging depths. Radial symmetry of arrangement maintains uniformity of collection efficiency across the whole FOV. Additionally, our probe can image at different tissue depths via axial actuation by a dc servo motor, allowing depth dependent tissue characterization. We designed our probe to perform imaging at 775 nm, targeting 2-photon autofluorescence from NAD(P)H and FAD molecules, which are often used in metabolic tissue characterization. An air core photonic bandgap fiber delivers laser pulses of 100 fs duration to the sample. A miniaturized objective designed with commercially available lenses of 3 mm diameter focuses the laser beam on tissue, attaining lateral and axial imaging resolutions of 0.66 µm and 4.65 µm, respectively. Characterization results verify that our probe achieves collection efficiency comparable to our optimized bench-top 2-photon imaging microscope, minimally affected by imaging depth and radial positioning. We validate autofluorescence imaging capability with excised porcine vocal fold tissue samples. Images with 120 µm FOV and 0.33 µm pixel sizes collected at 2 fps confirm that the 300 µm imaging depth was achieved.
Collapse
Affiliation(s)
- Berk Camli
- Department of Mechanical Engineering, UT Austin, Austin, Texas, USA
| | - Liam Andrus
- Department of Biomedical Engineering, UT Austin, Austin, Texas, USA
| | - Aditya Roy
- Department of Mechanical Engineering, UT Austin, Austin, Texas, USA
| | - Biswajit Mishra
- Department of Mechanical Engineering, UT Austin, Austin, Texas, USA
| | - Chris Xu
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York, USA
| | - Irene Georgakoudi
- Department of Biomedical Engineering, Tufts University, Medford, Massachusetts, USA
| | - Tomasz Tkaczyk
- Department of Bioengineering, Rice University, Houston, Texas, USA
| | - Adela Ben-Yakar
- Department of Mechanical Engineering, UT Austin, Austin, Texas, USA
- Department of Biomedical Engineering, UT Austin, Austin, Texas, USA
- Department of Electrical and Computer Engineering, UT Austin, Austin, Texas, USA
| |
Collapse
|
3
|
Yu CH, Yu Y, Adsit LM, Chang JT, Barchini J, Moberly AH, Benisty H, Kim J, Young BK, Heng K, Farinella DM, Leikvoll A, Pavan R, Vistein R, Nanfito BR, Hildebrand DGC, Otero-Coronel S, Vaziri A, Goldberg JL, Ricci AJ, Fitzpatrick D, Cardin JA, Higley MJ, Smith GB, Kara P, Nielsen KJ, Smith IT, Smith SL. The Cousa objective: a long-working distance air objective for multiphoton imaging in vivo. Nat Methods 2024; 21:132-141. [PMID: 38129618 PMCID: PMC10776402 DOI: 10.1038/s41592-023-02098-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Accepted: 10/23/2023] [Indexed: 12/23/2023]
Abstract
Multiphoton microscopy can resolve fluorescent structures and dynamics deep in scattering tissue and has transformed neural imaging, but applying this technique in vivo can be limited by the mechanical and optical constraints of conventional objectives. Short working distance objectives can collide with compact surgical windows or other instrumentation and preclude imaging. Here we present an ultra-long working distance (20 mm) air objective called the Cousa objective. It is optimized for performance across multiphoton imaging wavelengths, offers a more than 4 mm2 field of view with submicrometer lateral resolution and is compatible with commonly used multiphoton imaging systems. A novel mechanical design, wider than typical microscope objectives, enabled this combination of specifications. We share the full optical prescription, and report performance including in vivo two-photon and three-photon imaging in an array of species and preparations, including nonhuman primates. The Cousa objective can enable a range of experiments in neuroscience and beyond.
Collapse
Affiliation(s)
- Che-Hang Yu
- Department of Electrical and Computer Engineering, University of California Santa Barbara, Santa Barbara, CA, USA.
| | - Yiyi Yu
- Department of Electrical and Computer Engineering, University of California Santa Barbara, Santa Barbara, CA, USA
| | - Liam M Adsit
- Department of Molecular, Cellular, and Developmental Biology, University of California Santa Barbara, Santa Barbara, CA, USA
| | - Jeremy T Chang
- Max Planck Florida Institute for Neuroscience, Jupiter, FL, USA
| | - Jad Barchini
- Max Planck Florida Institute for Neuroscience, Jupiter, FL, USA
| | | | - Hadas Benisty
- Department of Neuroscience, Yale University, New Haven, CT, USA
| | - Jinkyung Kim
- Department of Otolaryngology, Washington University School of Medicine, St. Louis, MO, USA
| | - Brent K Young
- Spencer Center for Vision Research, Byers Eye Institute, School of Medicine, Stanford University, Palo Alto, CA, USA
| | - Kathleen Heng
- Spencer Center for Vision Research, Byers Eye Institute, School of Medicine, Stanford University, Palo Alto, CA, USA
- Neurosciences Interdepartmental Program, Stanford University, Stanford, CA, USA
| | - Deano M Farinella
- Department of Neuroscience, University of Minnesota, Minneapolis, MN, USA
| | - Austin Leikvoll
- Department of Neuroscience, University of Minnesota, Minneapolis, MN, USA
| | - Rishaab Pavan
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, USA
| | - Rachel Vistein
- Department of Molecular and Comparative Pathobiology, and Zanvyl Krieger Mind/Brain Institute, Johns Hopkins University, Baltimore, MD, USA
| | - Brandon R Nanfito
- Solomon H. Snyder Department of Neuroscience, and Zanvyl Krieger Mind/Brain Institute, Johns Hopkins University, Baltimore, MD, USA
| | | | - Santiago Otero-Coronel
- Laboratory of Neural Systems, The Rockefeller University, New York, NY, USA
- Laboratory of Neurotechnology and Biophysics, The Rockefeller University, New York, NY, USA
- Kavli Neural Systems Institute, The Rockefeller University, New York, NY, USA
| | - Alipasha Vaziri
- Laboratory of Neurotechnology and Biophysics, The Rockefeller University, New York, NY, USA
- Kavli Neural Systems Institute, The Rockefeller University, New York, NY, USA
| | - Jeffrey L Goldberg
- Spencer Center for Vision Research, Byers Eye Institute, School of Medicine, Stanford University, Palo Alto, CA, USA
| | - Anthony J Ricci
- Department of Otolaryngology, Stanford University School of Medicine, Stanford University, Stanford, CA, USA
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford University, Stanford, CA, USA
| | | | | | | | - Gordon B Smith
- Department of Neuroscience, University of Minnesota, Minneapolis, MN, USA
| | - Prakash Kara
- Department of Neuroscience, University of Minnesota, Minneapolis, MN, USA
| | - Kristina J Nielsen
- Solomon H. Snyder Department of Neuroscience, and Zanvyl Krieger Mind/Brain Institute, Johns Hopkins University, Baltimore, MD, USA
| | - Ikuko T Smith
- Department of Molecular, Cellular, and Developmental Biology, University of California Santa Barbara, Santa Barbara, CA, USA
- Department of Psychology and Brain Sciences, University of California Santa Barbara, Santa Barbara, CA, USA
- Neuroscience Research Institute, University of California Santa Barbara, Santa Barbara, CA, USA
| | - Spencer LaVere Smith
- Department of Electrical and Computer Engineering, University of California Santa Barbara, Santa Barbara, CA, USA.
- Department of Psychology and Brain Sciences, University of California Santa Barbara, Santa Barbara, CA, USA.
| |
Collapse
|
4
|
Xue Y, Boivin JR, Wadduwage DN, Park JK, Nedivi E, So PT. Multiline Orthogonal Scanning Temporal Focusing (mosTF) Microscopy for Scattering Reduction in High-speed in vivo Brain Imaging. RESEARCH SQUARE 2023:rs.3.rs-3576146. [PMID: 38014213 PMCID: PMC10680946 DOI: 10.21203/rs.3.rs-3576146/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
Temporal focusing two-photon microscopy enables high resolution imaging of fine structures in vivo over a large volume. A limitation of temporal focusing is that signal-to-background ratio and resolution degrade rapidly with increasing imaging depth. This degradation originates from the scattered emission photons are widely distributed resulting in a strong background. We have developed Multiline Orthogonal Scanning Temporal Focusing (mosTF) microscopy that overcomes this problem. mosTF captures a sequence of images at each scan location of the excitation line, followed by a reconstruction algorithm reassigns scattered photons back to the correct scan position. We demonstrate mosTF by acquiring mice neuronal images in vivo. Our results show remarkably improvements with mosTF for in vivo brain imaging while maintaining its speed advantage.
Collapse
Affiliation(s)
- Yi Xue
- Dept. of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139
- Laser Biomedical Research Center, Massachusetts Institute of Technology, Cambridge, MA 02139
- Dept. of Biomedical Engineering, University of California, Davis, CA 95616, USA
| | - Josiah R. Boivin
- Picower Institute, Massachusetts Institute of Technology, Cambridge, MA 02139
| | - Dushan N. Wadduwage
- Laser Biomedical Research Center, Massachusetts Institute of Technology, Cambridge, MA 02139
- Dept. of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139
- Center for Advanced Imaging, Faculty of Arts and Sciences, Harvard University, Cambridge, MA 02138
| | - Jong Kang Park
- Dept. of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139
| | - Elly Nedivi
- Picower Institute, Massachusetts Institute of Technology, Cambridge, MA 02139
- Dept. of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139
- Dept. of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139
| | - Peter T.C. So
- Dept. of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139
- Laser Biomedical Research Center, Massachusetts Institute of Technology, Cambridge, MA 02139
- Dept. of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139
| |
Collapse
|
5
|
Freymüller C, Ströbl S, Aumiller M, Eisel M, Sroka R, Rühm A. Development of a microstructured tissue phantom with adaptable optical properties for use with microscopes and fluorescence lifetime imaging systems. Lasers Surg Med 2022; 54:1010-1026. [PMID: 35753039 DOI: 10.1002/lsm.23556] [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: 10/28/2021] [Revised: 04/22/2022] [Accepted: 04/24/2022] [Indexed: 11/08/2022]
Abstract
OBJECTIVES For the development and validation of diagnostic procedures based on microscopic methods, knowledge about the imaging depth and achievable resolution in tissue is crucial. This poses the challenge to develop a microscopic artificial phantom focused on the microscopic instead of the macroscopic optical tissue characteristics. METHODS As existing artificial tissue phantoms designed for image forming systems are primarily targeted at wide field applications, they are unsuited for reaching the formulated objective. Therefore, a microscopy- and microendoscopy-suited artificial tissue phantom was developed and characterized. It is based on a microstructured glass surface coated with fluorescent beads at known depths covered by a scattering agent with modifiable optical properties. The phantom was examined with different kinds of microscopy systems in order to characterize its quality and stability and to demonstrate its usefulness for instrument comparison, for example, regarding structural as well as fluorescence lifetime analysis. RESULTS The analysis of the manufactured microstructured glass surfaces showed high regularity in their physical dimensions in accordance with the specifications. Measurements of the optical parameters of the scattering medium were consistent with simulations. The fluorescent beads coating proved to be stable for a respectable period of time (about a week). The developed artificial tissue phantom was successfully used to detect differences in image quality between a research microscope and an endoscopy based system. Plausible causes for the observed differences could be derived based on the well known microstructure of the phantom. CONCLUSIONS The artificial tissue phantom is well suited for the intended use with microscopic and microendoscopic systems. Due to its configurable design, it can be adapted to a wide range of applications. It is especially targeted at the characterization and calibration of clinical imaging systems that often lack extensive positioning capabilities such as an intrinsic z-stage.
Collapse
Affiliation(s)
- Christian Freymüller
- Laser-Forschungslabor, LIFE Center, Department of Urology, University Hospital, LMU Munich, Munich, Germany.,Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | - Stephan Ströbl
- Laser-Forschungslabor, LIFE Center, Department of Urology, University Hospital, LMU Munich, Munich, Germany.,Department of Urology, University Hospital, LMU Munich, Munich, Germany.,Research Center for Microtechnology, FH Vorarlberg, Dornbirn, Vorarlberg, Austria
| | - Maximilian Aumiller
- Laser-Forschungslabor, LIFE Center, Department of Urology, University Hospital, LMU Munich, Munich, Germany.,Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | - Maximilian Eisel
- Laser-Forschungslabor, LIFE Center, Department of Urology, University Hospital, LMU Munich, Munich, Germany.,Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | - Ronald Sroka
- Laser-Forschungslabor, LIFE Center, Department of Urology, University Hospital, LMU Munich, Munich, Germany.,Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | - Adrian Rühm
- Laser-Forschungslabor, LIFE Center, Department of Urology, University Hospital, LMU Munich, Munich, Germany.,Department of Urology, University Hospital, LMU Munich, Munich, Germany
| |
Collapse
|
6
|
Sun Y, Li L, Ma S, He G, Yang W, Wang Y. In vivo Visualization of Collagen Transdermal Absorption by Second-Harmonic Generation and Two-Photon Excited Fluorescence Microscopy. Front Chem 2022; 10:925931. [PMID: 35720999 PMCID: PMC9205562 DOI: 10.3389/fchem.2022.925931] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 05/09/2022] [Indexed: 11/20/2022] Open
Abstract
The transdermal administration of collagen is an important method used for wound healing and skin regeneration. However, due to the limitations of previous approaches, the process and degree of collagen transdermal absorption could only be quantitatively and qualitatively evaluated in vitro. In the present study, we introduced a novel approach that combines second-harmonic generation with two-photon excited fluorescence to visualize the dynamics of collagen transdermal absorption in vivo. High-resolution images showed that exogenous recombinant human collagen permeated the epidermis through hair follicles and sebaceous glands reached the dermis, and formed reticular structures in real time. We also validated these findings through traditional in vitro skin scanning and histological examination. Thus, our approach provides a reliable measurement for real-time evaluation of collagen absorption and treatment effects in vivo.
Collapse
Affiliation(s)
- Yanan Sun
- Experimental Research Center, China Academy of Chinese Medical Sciences, Beijing, China
- Beijing Key Laboratory of Research of Chinese Medicine on Prevention and Treatment for Major Disease, China Academy of Chinese Medical Sciences, Beijing, China
| | - Lishuang Li
- Experimental Research Center, China Academy of Chinese Medical Sciences, Beijing, China
- Beijing Key Laboratory of Research of Chinese Medicine on Prevention and Treatment for Major Disease, China Academy of Chinese Medical Sciences, Beijing, China
| | - Shuhua Ma
- Experimental Research Center, China Academy of Chinese Medical Sciences, Beijing, China
- Beijing Key Laboratory of Research of Chinese Medicine on Prevention and Treatment for Major Disease, China Academy of Chinese Medical Sciences, Beijing, China
| | - Gaiying He
- Experimental Research Center, China Academy of Chinese Medical Sciences, Beijing, China
- Beijing Key Laboratory of Research of Chinese Medicine on Prevention and Treatment for Major Disease, China Academy of Chinese Medical Sciences, Beijing, China
| | - Weifeng Yang
- Experimental Research Center, China Academy of Chinese Medical Sciences, Beijing, China
- Beijing Key Laboratory of Research of Chinese Medicine on Prevention and Treatment for Major Disease, China Academy of Chinese Medical Sciences, Beijing, China
| | - Yi Wang
- Experimental Research Center, China Academy of Chinese Medical Sciences, Beijing, China
- Beijing Key Laboratory of Research of Chinese Medicine on Prevention and Treatment for Major Disease, China Academy of Chinese Medical Sciences, Beijing, China
- *Correspondence: Yi Wang,
| |
Collapse
|
7
|
Sugashi T, Yuki H, Niizawa T, Takuwa H, Kanno I, Masamoto K. Three-dimensional microvascular network reconstruction from in vivo images with adaptation of the regional inhomogeneity in the signal-to-noise ratio. Microcirculation 2021; 28:e12697. [PMID: 33786951 DOI: 10.1111/micc.12697] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 02/19/2021] [Accepted: 03/22/2021] [Indexed: 11/27/2022]
Abstract
OBJECTIVE Quantification of angiographic images with two-photon laser scanning fluorescence microscopy (2PLSM) relies on proper segmentation of the vascular images. However, the images contain inhomogeneities in the signal-to-noise ratio (SNR) arising from regional effects of light scattering and absorption. The present study developed a semiautomated quantification method for volume images of 2PLSM angiography by adjusting the binarization threshold according to local SNR along the vessel centerlines. METHODS A phantom model made with fluorescent microbeads was used to incorporate a region-dependent binarization threshold. RESULTS The recommended SNR for imaging was found to be 4.2-10.6 that provide the true size of imaged objects if the binarization threshold was fixed at 50% of SNR. However, angiographic images in the mouse cortex showed variable SNR up to 45 over the depths. To minimize the errors caused by variable SNR and a spatial extent of the imaged objects in an axial direction, the microvascular networks were three-dimensionally reconstructed based on the cross-sectional diameters measured along the vessel centerline from the XY-plane images with adapted binarization threshold. The arterial volume was relatively constant over depths of 0-500 µm, and the capillary volume (1.7% relative to the scanned volume) showed the larger volumes than the artery (0.8%) and vein (0.6%). CONCLUSIONS The present methods allow consistent segmentation of microvasculature by adapting the local inhomogeneity in the SNR, which will be useful for quantitative comparison of the microvascular networks, such as under disease conditions where SNR in the 2PLSM images varies over space and time.
Collapse
Affiliation(s)
- Takuma Sugashi
- Department of Mechanical Engineering and Intelligent Systems, Graduate School of Informatics and Engineering, University of Electro-Communications, Chofu, Japan
| | - Hiroya Yuki
- Department of Mechanical Engineering and Intelligent Systems, Graduate School of Informatics and Engineering, University of Electro-Communications, Chofu, Japan
| | - Tomoya Niizawa
- Department of Mechanical Engineering and Intelligent Systems, Graduate School of Informatics and Engineering, University of Electro-Communications, Chofu, Japan
| | - Hiroyuki Takuwa
- Functional Brain Imaging Research, National Institute of Radiological Sciences, Chiba, Japan
| | - Iwao Kanno
- Functional Brain Imaging Research, National Institute of Radiological Sciences, Chiba, Japan
| | - Kazuto Masamoto
- Department of Mechanical Engineering and Intelligent Systems, Graduate School of Informatics and Engineering, University of Electro-Communications, Chofu, Japan.,Functional Brain Imaging Research, National Institute of Radiological Sciences, Chiba, Japan.,Center for Neuroscience and Biomedical Engineering, University of Electro-Communications, Chofu, Japan
| |
Collapse
|
8
|
Spatial Organization and Dynamics of the Extracellular Space in the Mouse Retina. J Neurosci 2020; 40:7785-7794. [PMID: 32887746 DOI: 10.1523/jneurosci.1717-20.2020] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 08/24/2020] [Accepted: 08/31/2020] [Indexed: 11/21/2022] Open
Abstract
The extracellular space (ECS) plays an important role in the physiology of neural circuits. Despite our detailed understanding of the cellular architecture of the mammalian retina, little is known about the organization and dynamics of the retinal ECS. We developed an optical technique based on two-photon imaging of fluorescently labeled extracellular fluid to measure the ECS volume fraction (α) in the ex vivo retina of male and female mice. This method has high spatial resolution and can detect rapid changes in α evoked by osmotic challenge and neuronal activity. The measured ECS α varied dramatically in different layers of the adult mouse retina, with α equaling ∼0.050 in the ganglion cell layer, ∼0.122 in the inner plexiform layer (IPL), ∼0.025 in the inner nuclear layer (INL), ∼0.087 in the outer plexiform layer, and ∼0.026 in the outer nuclear layer (ONL). ECS α was significantly larger early in retinal development; α was 67% larger in the IPL and 100% larger in the INL in neonatal mice compared with adults. In adult retinas, light stimulation evoked rapid decreases in ECS α. Light-driven reductions in ECS α were largest in the IPL, where visual stimuli decreased α values ∼10%. These light-evoked decreases demonstrate that a physiological stimulus can lead to rapid changes in ECS α and indicate that activity-dependent regulation of extracellular space may contribute to visual processing in the retina.SIGNIFICANCE STATEMENT The volume fraction of the extracellular space (ECS α), that portion of CNS tissue occupied by interstitial space, influences the diffusion of neurotransmitters from the synaptic cleft and the volume transmission of transmitters. However, ECS α has never been measured in live retina, and little is known about how ECS α varies following physiological stimulation. Here we show that ECS α values vary dramatically between different retinal layers and decrease by 10% following light stimulation. ECS α differences within the retina will influence volume transmission and light-evoked α variations may modulate synaptic transmission and visual processing in the retina. Activity-dependent ECS α variations may represent a mechanism of synaptic modulation throughout the CNS.
Collapse
|
9
|
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.
Collapse
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
| |
Collapse
|
10
|
Costantini I, Cicchi R, Silvestri L, Vanzi F, Pavone FS. In-vivo and ex-vivo optical clearing methods for biological tissues: review. BIOMEDICAL OPTICS EXPRESS 2019; 10:5251-5267. [PMID: 31646045 PMCID: PMC6788593 DOI: 10.1364/boe.10.005251] [Citation(s) in RCA: 86] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 06/09/2019] [Accepted: 06/11/2019] [Indexed: 05/05/2023]
Abstract
Every optical imaging technique is limited in its penetration depth by scattering occurring in biological tissues. Possible solutions to overcome this problem consist of limiting the detrimental effects of scattering by reducing optical inhomogeneities within the sample. This can be achieved either by using physical methods (such as refractive index matching solutions) or by chemical methods (such as the removal of scatterers), based on tissue transformation protocols. This review provides an overview of the current state-of-the-art methods used for both ex-vivo and in-vivo optical clearing of biological tissues. We start with a brief history of the development of the most widespread clearing methods across the new millennium, then we describe the working principles of both physical and chemical methods. Clearing methods are then reviewed, pointing the attention of the reader on both physical and chemical methods, classified based on the tissue size and type for each specific application. A small section is reserved for methods that have already found in-vivo applications at the research level. Finally, a detailed discussion highlighting both the most relevant results achieved and the new ongoing developments in this field is reported in the last part, together with future perspectives for the clearing methodology.
Collapse
Affiliation(s)
- Irene Costantini
- National Institute of Optics, National Research Council, Via Nello Carrara 1, 50019 Sesto Fiorentino, Italy
- European Laboratory for Non-linear Spectroscopy, University of Florence, Via Nello Carrara 1, 50019 Sesto Fiorentino, Italy
| | - Riccardo Cicchi
- National Institute of Optics, National Research Council, Via Nello Carrara 1, 50019 Sesto Fiorentino, Italy
- European Laboratory for Non-linear Spectroscopy, University of Florence, Via Nello Carrara 1, 50019 Sesto Fiorentino, Italy
| | - Ludovico Silvestri
- National Institute of Optics, National Research Council, Via Nello Carrara 1, 50019 Sesto Fiorentino, Italy
- European Laboratory for Non-linear Spectroscopy, University of Florence, Via Nello Carrara 1, 50019 Sesto Fiorentino, Italy
- Department of Physics and Astronomy, University of Florence, Via Sansone 1, Sesto Fiorentino, 50019, Italy
| | - Francesco Vanzi
- European Laboratory for Non-linear Spectroscopy, University of Florence, Via Nello Carrara 1, 50019 Sesto Fiorentino, Italy
- Department of Biology, University of Florence, Via Madonna del Piano 6, Sesto Fiorentino, 50019, Italy
| | - Francesco Saverio Pavone
- National Institute of Optics, National Research Council, Via Nello Carrara 1, 50019 Sesto Fiorentino, Italy
- European Laboratory for Non-linear Spectroscopy, University of Florence, Via Nello Carrara 1, 50019 Sesto Fiorentino, Italy
- Department of Physics and Astronomy, University of Florence, Via Sansone 1, Sesto Fiorentino, 50019, Italy
| |
Collapse
|
11
|
Pinsard M, Schmeltz M, van der Kolk J, Patten SA, Ibrahim H, Ramunno L, Schanne-Klein MC, Légaré F. Elimination of imaging artifacts in second harmonic generation microscopy using interferometry. BIOMEDICAL OPTICS EXPRESS 2019; 10:3938-3952. [PMID: 31452986 PMCID: PMC6701527 DOI: 10.1364/boe.10.003938] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 06/17/2019] [Accepted: 06/17/2019] [Indexed: 05/26/2023]
Abstract
Conventional second harmonic generation (SHG) microscopy might not clearly reveal the structure of complex samples if the interference between all scatterers in the focal volume results in artefactual patterns. We report here the use of interferometric second harmonic generation (I-SHG) microscopy to efficiently remove these artifacts from SHG images. Interfaces between two regions of opposite polarity are considered because they are known to produce imaging artifacts in muscle for instance. As a model system, such interfaces are first studied in periodically-poled lithium niobate (PPLN), where an artefactual incoherent SH signal is obtained because of irregularities at the interfaces, that overshadow the sought-after coherent contribution. Using I-SHG allows to remove the incoherent part completely without any spatial filtering. Second, I-SHG is also proven to resolve the double-band pattern expected in muscle where standard SHG exhibits in some regions artefactual single-band patterns. In addition to removing the artifacts at the interfaces between antiparallel domains in both structures (PPLN and muscle), I-SHG also increases their visibility by up to a factor of 5. This demonstrates that I-SHG is a powerful technique to image biological samples at enhanced contrast while suppressing artifacts.
Collapse
Affiliation(s)
- Maxime Pinsard
- Institut National de la Recherche Scientifique, Centre Énergie Matériaux Télécommunications (INRS-EMT); 1650 Boul. Lionel-Boulet, Varennes (QC), J3X 1S2, Canada
| | - Margaux Schmeltz
- Laboratoire d'Optique et Biosciences (LOB), École Polytechnique, CNRS, Inserm, Institut Polytechnique de Paris, F-91128 Palaiseau, France
| | - Jarno van der Kolk
- Department of Physics and Centre for Research in Photonics, University of Ottawa, Ottawa (ON), K1N 6N5, Canada
| | | | - Heide Ibrahim
- Institut National de la Recherche Scientifique, Centre Énergie Matériaux Télécommunications (INRS-EMT); 1650 Boul. Lionel-Boulet, Varennes (QC), J3X 1S2, Canada
| | - Lora Ramunno
- Department of Physics and Centre for Research in Photonics, University of Ottawa, Ottawa (ON), K1N 6N5, Canada
| | - Marie-Claire Schanne-Klein
- Laboratoire d'Optique et Biosciences (LOB), École Polytechnique, CNRS, Inserm, Institut Polytechnique de Paris, F-91128 Palaiseau, France
| | - François Légaré
- Institut National de la Recherche Scientifique, Centre Énergie Matériaux Télécommunications (INRS-EMT); 1650 Boul. Lionel-Boulet, Varennes (QC), J3X 1S2, Canada
| |
Collapse
|
12
|
Lysyl oxidase enzymes mediate TGF-β1-induced fibrotic phenotypes in human skin-like tissues. J Transl Med 2019; 99:514-527. [PMID: 30568176 DOI: 10.1038/s41374-018-0159-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 10/17/2018] [Accepted: 10/29/2018] [Indexed: 01/09/2023] Open
Abstract
Cutaneous fibrosis is a common complication seen in mixed connective tissue diseases. It often occurs as a result of TGF-β-induced deposition of excessive amounts of collagen in the skin. Lysyl oxidases (LOXs), a family of extracellular matrix (ECM)-modifying enzymes responsible for collagen cross-linking, are known to be increased in dermal fibroblasts from patients with fibrotic diseases, denoting a possible role of LOXs in fibrosis. To directly study this, we have developed two bioengineered, in vitro skin-like models: human skin equivalents (hSEs), and self-assembled stromal tissues (SASs) that contain either normal or systemic sclerosis (SSc; scleroderma) patient-derived fibroblasts. These tissues provide an organ-level structure that could be combined with non-invasive, label-free, multiphoton microscopy (SHG/TPEF) to reveal alterations in the organization and cross-linking levels of collagen fibers during the development of cutaneous fibrosis, which demonstrated increased stromal rigidity and activation of dermal fibroblasts in response to TGF-β1. Specifically, inhibition of specific LOXs isoforms, LOX and LOXL4, in foreskin fibroblasts (HFFs) resulted in antagonistic effects on TGF-β1-induced fibrogenic hallmarks in both hSEs and SASs. In addition, a translational relevance of these models was seen as similar antifibrogenic phenotypes were achieved upon knocking down LOXL4 in tissues containing SSc patient-derived-dermal fibroblasts (SScDFs). These findings point to a pivotal role of LOXs in TGF-β1-induced cutaneous fibrosis through impaired ECM homeostasis in skin-like tissues, and show the value of these tissue platforms in accelerating the discovery of antifibrosis therapeutics.
Collapse
|
13
|
Wang M, Kim M, Xia F, Xu C. Impact of the emission wavelengths on in vivo multiphoton imaging of mouse brains. BIOMEDICAL OPTICS EXPRESS 2019; 10:1905-1918. [PMID: 31061766 PMCID: PMC6485012 DOI: 10.1364/boe.10.001905] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Revised: 02/18/2019] [Accepted: 02/26/2019] [Indexed: 05/09/2023]
Abstract
Tissue scattering and absorption impact the excitation and emission light in different ways for multiphoton imaging. The collected fluorescence includes both ballistic photons and scattered photons whereas multiphoton excited signal within the focal volume is mostly generated by ballistic photons. The impact of excitation wavelengths on multiphoton imaging has been extensively investigated before; however, experimental data is lacking to evaluate the impact of emission wavelengths on fluorescence attenuation in deep imaging. Here we perform three-photon imaging of mouse brain vasculature in vivo using green, red, and near-infrared emission fluorophores, and compare quantitatively the attenuation of the fluorescence signal in the mouse brain at the emission wavelengths of 520 nm, 615 nm and 711 nm. Our results show that the emission wavelengths do not significantly influence the fluorescence collection efficiency. For the green, red and near-infrared fluorophores investigated, the difference in fluorescence collection efficiency is less than a factor of 2 at imaging depths between 0.6 and 1 mm. The advantage of long wavelength dyes for multiphoton deep imaging is almost entirely due to the long excitation wavelengths.
Collapse
|
14
|
Abstract
Two-photon calcium imaging became in recent years a very popular method for the functional analysis of neural cell populations on a single-cell level in anesthetized or awake behaving animals. Scientific insights about single-cell processing of sensory information but also analyses of higher cognitive functions in healthy or diseased states became thereby feasible. However, two-photon imaging is generally limited to depths of a few hundred micrometers when recording from densely labeled cell populations. Therefore, such recordings are often restricted to the superficial layers 1-3 of the mouse cortex, whereas the deep cell layers 4-6 are hardly accessible with standard two-photon imaging. Here, we provide a protocol for deep two-photon calcium imaging, which allows imaging of neuronal circuits with single-cell resolution in all cortical layers of the mouse primary cortex. This technique can be readily applied to other species. The method includes a reduction of excitation light scattering by the use of a red-shifted calcium indicator and the minimization of background fluorescence by visually guided local application of the fluorescent dye. The technique is similar to previously published protocols for in vivo two-photon calcium imaging with synthetic calcium dyes (Stosiek et al. Proc Natl Acad Sci U S A 100:7319-7324, 2003). Hence, only minor changes of a generic two-photon setup and some adaptations of the experimental procedures are required.
Collapse
Affiliation(s)
- Antje Birkner
- Institute of Neuroscience, Technical University of Munich, Munich, Germany.
- Munich Cluster for Systems Neurology (SyNergy) and Center for Integrated Protein Sciences (CIPSM), Munich, Germany.
| | - Arthur Konnerth
- Institute of Neuroscience, Technical University of Munich, Munich, Germany.
- Munich Cluster for Systems Neurology (SyNergy) and Center for Integrated Protein Sciences (CIPSM), Munich, Germany.
| |
Collapse
|
15
|
Del Bonis-O’Donnell JT, Chio L, Dorlhiac GF, McFarlane IR, Landry MP. Advances in Nanomaterials for Brain Microscopy. NANO RESEARCH 2018; 11:5144-5172. [PMID: 31105899 PMCID: PMC6516768 DOI: 10.1007/s12274-018-2145-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Revised: 07/05/2018] [Accepted: 07/08/2018] [Indexed: 05/19/2023]
Abstract
Microscopic imaging of the brain continues to reveal details of its structure, connectivity, and function. To further improve our understanding of the emergent properties and functions of neural circuits, new methods are necessary to directly visualize the relationship between brain structure, neuron activity, and neurochemistry. Advances in engineering the chemical and optical properties of nanomaterials concurrent with developments in deep-tissue microscopy hold tremendous promise for overcoming the current challenges associated with in vivo brain imaging, particularly for imaging the brain through optically-dense brain tissue, skull, and scalp. To this end, developments in nanomaterials offer much promise toward implementing tunable chemical functionality for neurochemical targeting and sensing, and fluorescence stability for long-term imaging. In this review, we summarize current brain microscopy methods and describe the diverse classes of nanomaterials recently leveraged as contrast agents and functional probes for microscopic optical imaging of the brain.
Collapse
Affiliation(s)
| | - Linda Chio
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA 94720
| | - Gabriel F Dorlhiac
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA 94720
| | - Ian R McFarlane
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA 94720
| | - Markita P Landry
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA 94720
- Innovative Genomics Institute (IGI), Berkeley, CA 94720
- California Institute for Quantitative Biosciences, QB3, University of California, Berkeley, CA 94720
- Chan-Zuckerberg Biohub, San Francisco, CA 94158
| |
Collapse
|
16
|
Wang M, Wu C, Sinefeld D, Li B, Xia F, Xu C. Comparing the effective attenuation lengths for long wavelength in vivo imaging of the mouse brain. BIOMEDICAL OPTICS EXPRESS 2018; 9:3534-3543. [PMID: 30338138 PMCID: PMC6191617 DOI: 10.1364/boe.9.003534] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 06/13/2018] [Accepted: 06/20/2018] [Indexed: 05/05/2023]
Abstract
Light attenuation in thick biological tissues, caused by a combination of absorption and scattering, limits the penetration depth in multiphoton microscopy (MPM). Both tissue scattering and absorption are dependent on wavelengths, which makes it essential to choose the excitation wavelength with minimum attenuation for deep imaging. Although theoretical models have been established to predict the wavelength dependence of light attenuation in brain tissues, the accuracy of these models in experimental settings needs to be verified. Furthermore, the water absorption contribution to the tissue attenuation, especially at 1450 nm where strong water absorption is predicted to be the dominant contributor in light attenuation, has not been confirmed. Here we performed a systematic study of in vivo three-photon imaging at different excitation wavelengths, 1300 nm, 1450 nm, 1500 nm, 1550 nm, and 1700 nm, and quantified the tissue attenuation by calculating the effective attenuation length at each wavelength. The experimental data show that the effective attenuation length at 1450 nm is significantly shorter than that at 1300 nm or 1700 nm. Our results provide unequivocal validation of the theoretical estimations based on water absorption and tissue scattering in predicting the effective attenuation lengths for long wavelength in vivo imaging.
Collapse
|
17
|
The Impact of Compressed Femtosecond Laser Pulse Durations on Neuronal Tissue Used for Two-Photon Excitation Through an Endoscope. Sci Rep 2018; 8:11124. [PMID: 30042504 PMCID: PMC6057889 DOI: 10.1038/s41598-018-29404-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Accepted: 07/11/2018] [Indexed: 11/09/2022] Open
Abstract
Accurate intraoperative tumour margin assessment is a major challenge in neurooncology, where sparse tumours beyond the bulk tumour are left undetected under conventional resection. Non-linear optical imaging can diagnose tissue at the sub-micron level and provide functional label-free histopathology in vivo. For this reason, a non-linear endomicroscope is being developed to characterize brain tissue intraoperatively based on multiple endogenous optical contrasts such as spectrally- and temporally-resolved fluorescence. To produce highly sensitive optical signatures that are specific to a given tissue type, short femtosecond pulsed lasers are required for efficient two-photon excitation. Yet, the potential of causing bio-damage has not been studied on neuronal tissue. Therefore, as a prerequisite to clinically testing the non-linear endomicroscope in vivo, the effect of short laser pulse durations (40-340 fs) on ex vivo brain tissue was investigated by monitoring the intensity, the spectral, and the lifetime properties of endogenous fluorophores under 800 and 890 nm two-photon excitation using a bi-modal non-linear endoscope. These properties were also validated by imaging samples on a benchtop multiphoton microscope. Our results show that under a constant mean laser power, excitation pulses as short as 40 fs do not negatively alter the biochemical/ biophysical properties of tissue even for prolonged irradiation.
Collapse
|
18
|
Lee S, Lee JH, Wang T, Jang WH, Yoon Y, Kim B, Jun YW, Kim MJ, Kim KH. Three-photon tissue imaging using moxifloxacin. Sci Rep 2018; 8:9415. [PMID: 29925864 PMCID: PMC6010410 DOI: 10.1038/s41598-018-27371-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Accepted: 05/30/2018] [Indexed: 12/13/2022] Open
Abstract
Moxifloxacin is an antibiotic used in clinics and has recently been used as a clinically compatible cell-labeling agent for two-photon (2P) imaging. Although 2P imaging with moxifloxacin labeling visualized cells inside tissues using enhanced fluorescence, the imaging depth was quite limited because of the relatively short excitation wavelength (<800 nm) used. In this study, the feasibility of three-photon (3P) excitation of moxifloxacin using a longer excitation wavelength and moxifloxacin-based 3P imaging were tested to increase the imaging depth. Moxifloxacin fluorescence via 3P excitation was detected at a >1000 nm excitation wavelength. After obtaining the excitation and emission spectra of moxifloxacin, moxifloxacin-based 3P imaging was applied to ex vivo mouse bladder and ex vivo mouse small intestine tissues and compared with moxifloxacin-based 2P imaging by switching the excitation wavelength of a Ti:sapphire oscillator between near 1030 and 780 nm. Both moxifloxacin-based 2P and 3P imaging visualized cellular structures in the tissues via moxifloxacin labeling, but the image contrast was better with 3P imaging than with 2P imaging at the same imaging depths. The imaging speed and imaging depth of moxifloxacin-based 3P imaging using a Ti:sapphire oscillator were limited by insufficient excitation power. Therefore, we constructed a new system for moxifloxacin-based 3P imaging using a high-energy Yb fiber laser at 1030 nm and used it for in vivo deep tissue imaging of a mouse small intestine. Moxifloxacin-based 3P imaging could be useful for clinical applications with enhanced imaging depth.
Collapse
Affiliation(s)
- Seunghun Lee
- Department of Mechanical Engineering, Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk, 37673, Republic of Korea
| | - Jun Ho Lee
- Department of Mechanical Engineering, Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk, 37673, Republic of Korea
| | - Taejun Wang
- Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk, 37673, Republic of Korea
| | - Won Hyuk Jang
- Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk, 37673, Republic of Korea
| | - Yeoreum Yoon
- Department of Mechanical Engineering, Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk, 37673, Republic of Korea
| | - Bumju Kim
- Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk, 37673, Republic of Korea
| | - Yong Woong Jun
- Department of Chemistry, Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk, 37673, Republic of Korea
| | - Myoung Joon Kim
- Department of Ophthalmology, University of Ulsan College of Medicine, Asan Medical Center, 88 Olympic-ro 43-gil, Songpa-gu, Seoul, 05505, Republic of Korea
| | - Ki Hean Kim
- Department of Mechanical Engineering, Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk, 37673, Republic of Korea. .,Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk, 37673, Republic of Korea.
| |
Collapse
|
19
|
Yeh SCA, Wilk K, Lin CP, Intini G. In Vivo 3D Histomorphometry Quantifies Bone Apposition and Skeletal Progenitor Cell Differentiation. Sci Rep 2018; 8:5580. [PMID: 29615817 PMCID: PMC5882859 DOI: 10.1038/s41598-018-23785-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 03/20/2018] [Indexed: 01/07/2023] Open
Abstract
Histomorphometry and Micro-CT are commonly used to assess bone remodeling and bone microarchitecture. These approaches typically require separate cohorts of animals to analyze 3D morphological changes and involve time-consuming immunohistochemistry preparation. Intravital Microscopy (IVM) in combination with mouse genetics may represent an attractive option to obtain bone architectural measurements while performing longitudinal monitoring of dynamic cellular processes in vivo. In this study we utilized two-photon, multicolor fluorescence IVM together with a lineage tracing reporter mouse model to image skeletal stem cells (SSCs) in their calvarial suture niche and analyze their differentiation fate after stimulation with an agonist of the canonical Wnt pathway (recombinant Wnt3a). Our in vivo histomorphometry analyses of bone formation, suture volume, and cellular dynamics showed that recombinant Wnt3a induces new bone formation, differentiation and incorporation of SSCs progeny into newly forming bone. IVM technology can therefore provide additional dynamic 3D information to the traditional static 2D histomorphometry.
Collapse
Affiliation(s)
- Shu-Chi A Yeh
- Department of Oral Medicine, Infection, and Immunity, Harvard School of Dental Medicine, Boston, MA, 02115, USA.,Advanced Microscopy Program, Center for Systems Biology and Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, 02114, USA
| | - Katarzyna Wilk
- Department of Oral Medicine, Infection, and Immunity, Harvard School of Dental Medicine, Boston, MA, 02115, USA
| | - Charles P Lin
- Advanced Microscopy Program, Center for Systems Biology and Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, 02114, USA. .,Harvard Stem Cell Institute, Cambridge, MA, 02138, USA.
| | - Giuseppe Intini
- Department of Oral Medicine, Infection, and Immunity, Harvard School of Dental Medicine, Boston, MA, 02115, USA. .,Harvard Stem Cell Institute, Cambridge, MA, 02138, USA.
| |
Collapse
|
20
|
Piazza S, Bianchini P, Sheppard C, Diaspro A, Duocastella M. Enhanced volumetric imaging in 2-photon microscopy via acoustic lens beam shaping. JOURNAL OF BIOPHOTONICS 2018; 11:e201700050. [PMID: 28700127 DOI: 10.1002/jbio.201700050] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Revised: 06/20/2017] [Accepted: 06/21/2017] [Indexed: 05/26/2023]
Abstract
Three-dimensional imaging at high-spatiotemporal resolutions and over large penetration depths is key for unmasking the dynamics and structural organization of complex biological systems. However, the need to axially shift the focus, with consequent limitations in imaging speed, and signal degradation at large depths due to scattering effects, makes this task challenging. Here, we present a novel approach in 2-photon excitation microscopy that allows fast volumetric imaging and enhanced signal-to-background (S/B) in thick tissue. Our technique is based on ultrafast beam shaping at each pixel by means of an acoustic optofluidic lens. Shaping the excitation beam with different phase profiles enables both high-speed axial focus shifting, for continuous volumetric imaging, and controlled aberrated imaging, advantageous for out-of-focus background removal. We provide a theoretical description of our approach, and demonstrate volumetric imaging of neuronal cells from a mouse brain slice with enhancements in S/B up to a factor of 10 over a depth of 600 μm.
Collapse
Affiliation(s)
- Simonluca Piazza
- Nanoscopy, Istituto Italiano di Tecnologia, Genoa, Italy
- DIBRIS, Università degli Studi di Genova, Genoa, Italy
| | | | - Colin Sheppard
- Nanoscopy, Istituto Italiano di Tecnologia, Genoa, Italy
| | - Alberto Diaspro
- Nanoscopy, Istituto Italiano di Tecnologia, Genoa, Italy
- Department of Physics, Università degli Studi di Genova, Genoa, Italy
| | | |
Collapse
|
21
|
Miller JP, Maji D, Lam J, Tromberg BJ, Achilefu S. Noninvasive depth estimation using tissue optical properties and a dual-wavelength fluorescent molecular probe in vivo. BIOMEDICAL OPTICS EXPRESS 2017; 8:3095-3109. [PMID: 28663929 PMCID: PMC5480452 DOI: 10.1364/boe.8.003095] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Revised: 05/21/2017] [Accepted: 05/25/2017] [Indexed: 05/28/2023]
Abstract
Translation of fluorescence imaging using molecularly targeted imaging agents for real-time assessment of surgical margins in the operating room requires a fast and reliable method to predict tumor depth from planar optical imaging. Here, we developed a dual-wavelength fluorescent molecular probe with distinct visible and near-infrared excitation and emission spectra for depth estimation in mice and a method to predict the optical properties of the imaging medium such that the technique is applicable to a range of medium types. Imaging was conducted at two wavelengths in a simulated blood vessel and an in vivo tumor model. Although the depth estimation method was insensitive to changes in the molecular probe concentration, it was responsive to the optical parameters of the medium. Results of the intra-tumor fluorescent probe injection showed that the average measured tumor sub-surface depths were 1.31 ± 0.442 mm, 1.07 ± 0.187 mm, and 1.42 ± 0.182 mm, and the average estimated sub-surface depths were 0.97 ± 0.308 mm, 1.11 ± 0.428 mm, 1.21 ± 0.492 mm, respectively. Intravenous injection of the molecular probe allowed for selective tumor accumulation, with measured tumor sub-surface depths of 1.28 ± 0.168 mm, and 1.50 ± 0.394 mm, and the estimated depths were 1.46 ± 0.314 mm, and 1.60 ± 0.409 mm, respectively. Expansion of our technique by using material optical properties and mouse skin optical parameters to estimate the sub-surface depth of a tumor demonstrated an agreement between measured and estimated depth within 0.38 mm and 0.63 mm for intra-tumor and intravenous dye injections, respectively. Our results demonstrate the feasibility of dual-wavelength imaging for determining the depth of blood vessels and characterizing the sub-surface depth of tumors in vivo.
Collapse
Affiliation(s)
- Jessica P. Miller
- Optical Radiology Lab, Mallinckrodt Institute of Radiology, Washington University School of Medicine, 4515 McKinley Ave, St. Louis, Missouri 63110, USA
- Biomedical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, USA
- Co-contributing first authors contributed equally
| | - Dolonchampa Maji
- Optical Radiology Lab, Mallinckrodt Institute of Radiology, Washington University School of Medicine, 4515 McKinley Ave, St. Louis, Missouri 63110, USA
- Biomedical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, USA
- Co-contributing first authors contributed equally
| | - Jesse Lam
- Laser Microbeam and Medical Program, Beckman Laser Institute, University of California, Irvine, Irvine, California 92612, USA
| | - Bruce J. Tromberg
- Laser Microbeam and Medical Program, Beckman Laser Institute, University of California, Irvine, Irvine, California 92612, USA
| | - Samuel Achilefu
- Optical Radiology Lab, Mallinckrodt Institute of Radiology, Washington University School of Medicine, 4515 McKinley Ave, St. Louis, Missouri 63110, USA
- Biomedical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, USA
| |
Collapse
|
22
|
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
| |
Collapse
|
23
|
Cicchi R, Pavone FS. Probing Collagen Organization: Practical Guide for Second-Harmonic Generation (SHG) Imaging. Methods Mol Biol 2017; 1627:409-425. [PMID: 28836217 DOI: 10.1007/978-1-4939-7113-8_27] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Second-harmonic generation (SHG) microscopy is a powerful microscopy technique for imaging collagen and other biological molecules using a label-free approach. SHG microscopy offers the advantages of a nonlinear imaging modality together with those ones of a coherent technique. These features make SHG microscopy the ideal tool for imaging collagen at high resolution and for characterizing its organization at various hierarchical levels. Considering that collagen organization plays a crucial role in fibrosis and in its development, it would be beneficial for the researcher working in the field of fibrosis to have a manual listing crucial points to be considered when imaging collagen using SHG microscopy. This chapter provides an answer to this demand with state-of-the-art protocols, methods, and laboratory tips related to SHG microscopy. We also discuss advantages and limitations of the use of SHG for studying fibrosis.
Collapse
Affiliation(s)
- Riccardo Cicchi
- National Institute of Optics, National Research Council (INO-CNR), Sesto Fiorentino, Italy.
- European Laboratory for Non-linear Spectroscopy (LENS), University of Florence, Sesto Fiorentino, Italy.
| | - Francesco S Pavone
- European Laboratory for Non-linear Spectroscopy (LENS), University of Florence, Sesto Fiorentino, Italy
- Department of Physics, University of Florence, Sesto Fiorentino, Italy
| |
Collapse
|
24
|
Perillo EP, Jarrett JW, Liu YL, Hassan A, Fernée DC, Goldak JR, Bonteanu A, Spence DJ, Yeh HC, Dunn AK. Two-color multiphoton in vivo imaging with a femtosecond diamond Raman laser. LIGHT, SCIENCE & APPLICATIONS 2017; 6. [PMID: 29576887 PMCID: PMC5863928 DOI: 10.1038/lsa.2017.95] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Two-color multiphoton microscopy through wavelength mixing of synchronized lasers has been shown to increase the spectral window of excitable fluorophores without the need for wavelength tuning. However, most currently available dual output laser sources rely on the costly and complicated optical parametric generation approach. In this report, we detail a relatively simple and low cost diamond Raman laser pumped by a ytterbium fiber amplifier emitting at 1055 nm, which generates a first Stokes emission centered at 1240 nm with a pulse width of 100 fs. The two excitation wavelengths of 1055 and 1240 nm, along with the effective two-color excitation wavelength of 1140 nm, provide an almost complete coverage of fluorophores excitable within the range of 1000-1300 nm. When compared with 1055 nm excitation, two-color excitation at 1140 nm offers a 90% increase in signal for many far-red emitting fluorescent proteins (for example, tdKatushka2). We demonstrate multicolor imaging of tdKa-tushka2 and Hoechst 33342 via simultaneous two-color two-photon, and two-color three-photon microscopy in engineered 3D multicellular spheroids. We further discuss potential benefits and applications for two-color three-photon excitation. In addition, we show that this laser system is capable of in vivo imaging in mouse cortex to nearly 1 mm in depth with two-color excitation.
Collapse
Affiliation(s)
- Evan P Perillo
- Department of Biomedical Engineering, The University of Texas at Austin, TX 78712, USA
| | - Jeremy W Jarrett
- Department of Biomedical Engineering, The University of Texas at Austin, TX 78712, USA
| | - Yen-Liang Liu
- Department of Biomedical Engineering, The University of Texas at Austin, TX 78712, USA
| | - Ahmed Hassan
- Department of Biomedical Engineering, The University of Texas at Austin, TX 78712, USA
| | - Daniel C Fernée
- Department of Biomedical Engineering, The University of Texas at Austin, TX 78712, USA
| | - John R Goldak
- Department of Physics, The University of Texas at Austin, TX 78712, USA
| | - Andrei Bonteanu
- Department of Biomedical Engineering, The University of Texas at Austin, TX 78712, USA
| | - David J Spence
- MQ Photonics, Department of Physics and Astronomy, Macquarie University, Sydney, NSW 2109, Australia
| | - Hsin-Chih Yeh
- Department of Biomedical Engineering, The University of Texas at Austin, TX 78712, USA
| | - Andrew K Dunn
- Department of Biomedical Engineering, The University of Texas at Austin, TX 78712, USA
| |
Collapse
|
25
|
Levy ES, Tajon CA, Bischof TS, Iafrati J, Fernandez-Bravo A, Garfield DJ, Chamanzar M, Maharbiz MM, Sohal VS, Schuck PJ, Cohen BE, Chan EM. Energy-Looping Nanoparticles: Harnessing Excited-State Absorption for Deep-Tissue Imaging. ACS NANO 2016; 10:8423-33. [PMID: 27603228 DOI: 10.1021/acsnano.6b03288] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Near infrared (NIR) microscopy enables noninvasive imaging in tissue, particularly in the NIR-II spectral range (1000-1400 nm) where attenuation due to tissue scattering and absorption is minimized. Lanthanide-doped upconverting nanocrystals are promising deep-tissue imaging probes due to their photostable emission in the visible and NIR, but these materials are not efficiently excited at NIR-II wavelengths due to the dearth of lanthanide ground-state absorption transitions in this window. Here, we develop a class of lanthanide-doped imaging probes that harness an energy-looping mechanism that facilitates excitation at NIR-II wavelengths, such as 1064 nm, that are resonant with excited-state absorption transitions but not ground-state absorption. Using computational methods and combinatorial screening, we have identified Tm(3+)-doped NaYF4 nanoparticles as efficient looping systems that emit at 800 nm under continuous-wave excitation at 1064 nm. Using this benign excitation with standard confocal microscopy, energy-looping nanoparticles (ELNPs) are imaged in cultured mammalian cells and through brain tissue without autofluorescence. The 1 mm imaging depths and 2 μm feature sizes are comparable to those demonstrated by state-of-the-art multiphoton techniques, illustrating that ELNPs are a promising class of NIR probes for high-fidelity visualization in cells and tissue.
Collapse
Affiliation(s)
- Elizabeth S Levy
- The Molecular Foundry, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States
| | - Cheryl A Tajon
- The Molecular Foundry, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States
| | - Thomas S Bischof
- The Molecular Foundry, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States
| | - Jillian Iafrati
- Department of Psychiatry, University of California , San Francisco, California 94143, United States
| | - Angel Fernandez-Bravo
- The Molecular Foundry, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States
| | - David J Garfield
- The Molecular Foundry, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States
| | | | | | - Vikaas S Sohal
- Department of Psychiatry, University of California , San Francisco, California 94143, United States
| | - P James Schuck
- The Molecular Foundry, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States
| | - Bruce E Cohen
- The Molecular Foundry, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States
| | - Emory M Chan
- The Molecular Foundry, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States
| |
Collapse
|
26
|
Dvornikov A, Gratton E. Imaging in turbid media: a transmission detector gives 2-3 order of magnitude enhanced sensitivity compared to epi-detection schemes. BIOMEDICAL OPTICS EXPRESS 2016; 7:3747-3755. [PMID: 27699135 PMCID: PMC5030047 DOI: 10.1364/boe.7.003747] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 08/25/2016] [Accepted: 08/25/2016] [Indexed: 05/26/2023]
Abstract
Imaging depth in turbid media by two-photon fluorescence microscopy depends on the ability of the optical system to detect weak fluorescence signals. We have shown that use of a wide area detector in transmission geometry allows increasing imaging depth in turbid media due to efficient photon collection. Compared to the conventional epi-detection scheme used in most commercial microscopes, the transmission detector was found to be 2-3 orders of magnitude more sensitive when used for in depth imaging in scattering samples simulating brain optical properties.
Collapse
|
27
|
Harris KD, Quian Quiroga R, Freeman J, Smith S. Improving data quality in neuronal population recordings. Nat Neurosci 2016; 19:1165-74. [PMID: 27571195 PMCID: PMC5244825 DOI: 10.1038/nn.4365] [Citation(s) in RCA: 131] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Accepted: 07/20/2016] [Indexed: 12/12/2022]
Abstract
Understanding how the brain operates requires understanding how large sets of neurons function together. Modern recording technology makes it possible to simultaneously record the activity of hundreds of neurons, and technological developments will soon allow recording of thousands or tens of thousands. As with all experimental techniques, these methods are subject to confounds that complicate the interpretation of such recordings, and could lead to erroneous scientific conclusions. Here we discuss methods for assessing and improving the quality of data from these techniques and outline likely future directions in this field.
Collapse
Affiliation(s)
- Kenneth D. Harris
- UCL Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK
- UCL Department of Neuroscience, Physiology and Pharmacology, University College London, 21 University Street, London WC1E 6DE, UK
| | | | - Jeremy Freeman
- Howard Hughes Medical Institute, Janelia Farm Research Campus, 19700 Helix Drive, Ashburn VA 20147, USA
| | - Spencer Smith
- Department of Cell Biology and Physiology, UNC School of Medicine, Chapel Hill NC 27599, USA
| |
Collapse
|
28
|
Superresolved multiphoton microscopy with spatial frequency-modulated imaging. Proc Natl Acad Sci U S A 2016; 113:6605-10. [PMID: 27231219 DOI: 10.1073/pnas.1602811113] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Superresolved far-field microscopy has emerged as a powerful tool for investigating the structure of objects with resolution well below the diffraction limit of light. Nearly all superresolution imaging techniques reported to date rely on real energy states of fluorescent molecules to circumvent the diffraction limit, preventing superresolved imaging with contrast mechanisms that occur via virtual energy states, including harmonic generation (HG). We report a superresolution technique based on spatial frequency-modulated imaging (SPIFI) that permits superresolved nonlinear microscopy with any contrast mechanism and with single-pixel detection. We show multimodal superresolved images with two-photon excited fluorescence (TPEF) and second-harmonic generation (SHG) from biological and inorganic media. Multiphoton SPIFI (MP-SPIFI) provides spatial resolution up to 2η below the diffraction limit, where η is the highest power of the nonlinear intensity response. MP-SPIFI can be used to provide enhanced resolution in optically thin media and may provide a solution for superresolved imaging deep in scattering media.
Collapse
|
29
|
Fischer MC, Wilson JW, Robles FE, Warren WS. Invited Review Article: Pump-probe microscopy. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:031101. [PMID: 27036751 PMCID: PMC4798998 DOI: 10.1063/1.4943211] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 02/07/2016] [Indexed: 05/17/2023]
Abstract
Multiphoton microscopy has rapidly gained popularity in biomedical imaging and materials science because of its ability to provide three-dimensional images at high spatial and temporal resolution even in optically scattering environments. Currently the majority of commercial and home-built devices are based on two-photon fluorescence and harmonic generation contrast. These two contrast mechanisms are relatively easy to measure but can access only a limited range of endogenous targets. Recent developments in fast laser pulse generation, pulse shaping, and detection technology have made accessible a wide range of optical contrasts that utilize multiple pulses of different colors. Molecular excitation with multiple pulses offers a large number of adjustable parameters. For example, in two-pulse pump-probe microscopy, one can vary the wavelength of each excitation pulse, the detection wavelength, the timing between the excitation pulses, and the detection gating window after excitation. Such a large parameter space can provide much greater molecular specificity than existing single-color techniques and allow for structural and functional imaging without the need for exogenous dyes and labels, which might interfere with the system under study. In this review, we provide a tutorial overview, covering principles of pump-probe microscopy and experimental setup, challenges associated with signal detection and data processing, and an overview of applications.
Collapse
Affiliation(s)
- Martin C Fischer
- Department of Chemistry, Duke University, Durham, North Carolina 27708, USA
| | - Jesse W Wilson
- Department of Chemistry, Duke University, Durham, North Carolina 27708, USA
| | - Francisco E Robles
- Department of Chemistry, Duke University, Durham, North Carolina 27708, USA
| | - Warren S Warren
- Departments of Chemistry, Biomedical Engineering, Physics, and Radiology, Duke University, Durham, North Carolina 27708, USA
| |
Collapse
|
30
|
Bancelin S, Couture CA, Légaré K, Pinsard M, Rivard M, Brown C, Légaré F. Fast interferometric second harmonic generation microscopy. BIOMEDICAL OPTICS EXPRESS 2016; 7:399-408. [PMID: 26977349 PMCID: PMC4771458 DOI: 10.1364/boe.7.000399] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 01/05/2016] [Accepted: 01/05/2016] [Indexed: 05/29/2023]
Abstract
We report the implementation of fast Interferometric Second Harmonic Generation (I-SHG) microscopy to study the polarity of non-centrosymmetric structures in biological tissues. Using a sample quartz plate, we calibrate the spatially varying phase shift introduced by the laser scanning system. Compensating this phase shift allows us to retrieve the correct phase distribution in periodically poled lithium niobate, used as a model sample. Finally, we used fast interferometric second harmonic generation microscopy to acquire phase images in tendon. Our results show that the method exposed here, using a laser scanning system, allows to recover the polarity of collagen fibrils, similarly to standard I-SHG (using a sample scanning system), but with an imaging time about 40 times shorter.
Collapse
Affiliation(s)
- Stéphane Bancelin
- Institut National de la Recherche Scientifique, Centre Énergie Matériaux Télécommunications (INRS-EMT); 1650 Boul. Lionel-Boulet, Varennes (QC), J3X 1S2, Canada
| | - Charles-André Couture
- Institut National de la Recherche Scientifique, Centre Énergie Matériaux Télécommunications (INRS-EMT); 1650 Boul. Lionel-Boulet, Varennes (QC), J3X 1S2, Canada
| | - Katherine Légaré
- Institut National de la Recherche Scientifique, Centre Énergie Matériaux Télécommunications (INRS-EMT); 1650 Boul. Lionel-Boulet, Varennes (QC), J3X 1S2, Canada
| | - Maxime Pinsard
- Institut National de la Recherche Scientifique, Centre Énergie Matériaux Télécommunications (INRS-EMT); 1650 Boul. Lionel-Boulet, Varennes (QC), J3X 1S2, Canada
| | - Maxime Rivard
- Institut National de la Recherche Scientifique, Centre Énergie Matériaux Télécommunications (INRS-EMT); 1650 Boul. Lionel-Boulet, Varennes (QC), J3X 1S2, Canada
| | - Cameron Brown
- University of Oxford, Botnar Research Center, NDORMS, Windmill Road, Oxford, OX3 7HE, UK
| | - François Légaré
- Institut National de la Recherche Scientifique, Centre Énergie Matériaux Télécommunications (INRS-EMT); 1650 Boul. Lionel-Boulet, Varennes (QC), J3X 1S2, Canada
| |
Collapse
|
31
|
Perillo EP, McCracken JE, Fernée DC, Goldak JR, Medina FA, Miller DR, Yeh HC, Dunn AK. Deep in vivo two-photon microscopy with a low cost custom built mode-locked 1060 nm fiber laser. BIOMEDICAL OPTICS EXPRESS 2016; 7:324-34. [PMID: 26977343 PMCID: PMC4771452 DOI: 10.1364/boe.7.000324] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Revised: 12/17/2015] [Accepted: 12/17/2015] [Indexed: 05/21/2023]
Abstract
Here we demonstrate that a mode-locked ytterbium fiber laser for two-photon fluorescence microscopy can be built for $13,000. The laser emits at a wavelength of 1060 nm with a usable average power of 1 W at a repetition rate of 40 MHz and a compressed pulse width of 81 fs at the sample. The laser is used to obtain deep in vivo two-color images of layer-V pyramidal neurons expressing YFP and vasculature labelled with Texas Red at depths up to 900 µm. The sub-1 µm features of dendritic spines can be resolved at a 200 µm depth.
Collapse
Affiliation(s)
- Evan P. Perillo
- Department of Biomedical Engineering, The University of Texas at Austin, 107 W. Dean Keeton C0800, Austin, Texas 78712, USA
| | - Justin E. McCracken
- Department of Biomedical Engineering, The University of Texas at Austin, 107 W. Dean Keeton C0800, Austin, Texas 78712, USA
| | - Daniel C. Fernée
- Department of Biomedical Engineering, The University of Texas at Austin, 107 W. Dean Keeton C0800, Austin, Texas 78712, USA
| | - John R. Goldak
- Department of Biomedical Engineering, The University of Texas at Austin, 107 W. Dean Keeton C0800, Austin, Texas 78712, USA
| | - Flor A. Medina
- Department of Biomedical Engineering, The University of Texas at Austin, 107 W. Dean Keeton C0800, Austin, Texas 78712, USA
| | - David R. Miller
- Department of Biomedical Engineering, The University of Texas at Austin, 107 W. Dean Keeton C0800, Austin, Texas 78712, USA
| | - Hsin-Chih Yeh
- Department of Biomedical Engineering, The University of Texas at Austin, 107 W. Dean Keeton C0800, Austin, Texas 78712, USA
| | - Andrew K. Dunn
- Department of Biomedical Engineering, The University of Texas at Austin, 107 W. Dean Keeton C0800, Austin, Texas 78712, USA
| |
Collapse
|
32
|
Tischbirek C, Birkner A, Jia H, Sakmann B, Konnerth A. Deep two-photon brain imaging with a red-shifted fluorometric Ca2+ indicator. Proc Natl Acad Sci U S A 2015; 112:11377-82. [PMID: 26305966 PMCID: PMC4568712 DOI: 10.1073/pnas.1514209112] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In vivo Ca2+ imaging of neuronal populations in deep cortical layers has remained a major challenge, as the recording depth of two-photon microscopy is limited because of the scattering and absorption of photons in brain tissue. A possible strategy to increase the imaging depth is the use of red-shifted fluorescent dyes, as scattering of photons is reduced at long wavelengths. Here, we tested the red-shifted fluorescent Ca2+ indicator Cal-590 for deep tissue experiments in the mouse cortex in vivo. In experiments involving bulk loading of neurons with the acetoxymethyl (AM) ester version of Cal-590, combined two-photon imaging and cell-attached recordings revealed that, despite the relatively low affinity of Cal-590 for Ca2+ (Kd=561 nM), single-action potential-evoked Ca2+ transients were discernable in most neurons with a good signal-to-noise ratio. Action potential-dependent Ca2+ transients were recorded in neurons of all six layers of the cortex at depths of up to -900 µm below the pial surface. We demonstrate that Cal-590 is also suited for multicolor functional imaging experiments in combination with other Ca2+ indicators. Ca2+ transients in the dendrites of an individual Oregon green 1,2-bis(o-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid-1 (OGB-1)-labeled neuron and the surrounding population of Cal-590-labeled cells were recorded simultaneously on two spectrally separated detection channels. We conclude that the red-shifted Ca2+ indicator Cal-590 is well suited for in vivo two-photon Ca2+ imaging experiments in all layers of mouse cortex. In combination with spectrally different Ca2+ indicators, such as OGB-1, Cal-590 can be readily used for simultaneous multicolor functional imaging experiments.
Collapse
Affiliation(s)
- Carsten Tischbirek
- Institute for Neuroscience, Technische Universität München, 80802 Munich, Germany; Munich Cluster for Systems Neurology, 80802 Munich, Germany; Center for Integrated Protein Sciences, 80802 Munich, Germany
| | - Antje Birkner
- Institute for Neuroscience, Technische Universität München, 80802 Munich, Germany; Munich Cluster for Systems Neurology, 80802 Munich, Germany; Center for Integrated Protein Sciences, 80802 Munich, Germany
| | - Hongbo Jia
- Institute for Neuroscience, Technische Universität München, 80802 Munich, Germany; Munich Cluster for Systems Neurology, 80802 Munich, Germany; Center for Integrated Protein Sciences, 80802 Munich, Germany
| | - Bert Sakmann
- Institute for Neuroscience, Technische Universität München, 80802 Munich, Germany;
| | - Arthur Konnerth
- Institute for Neuroscience, Technische Universität München, 80802 Munich, Germany; Munich Cluster for Systems Neurology, 80802 Munich, Germany; Center for Integrated Protein Sciences, 80802 Munich, Germany
| |
Collapse
|
33
|
Cha JW, Yew EYS, Kim D, Subramanian J, Nedivi E, So PTC. Non-descanned multifocal multiphoton microscopy with a multianode photomultiplier tube. AIP ADVANCES 2015; 5:084802. [PMID: 25874160 PMCID: PMC4387602 DOI: 10.1063/1.4916040] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Accepted: 09/28/2014] [Indexed: 05/25/2023]
Abstract
Multifocal multiphoton microscopy (MMM) improves imaging speed over a point scanning approach by parallelizing the excitation process. Early versions of MMM relied on imaging detectors to record emission signals from multiple foci simultaneously. For many turbid biological specimens, the scattering of emission photons results in blurred images and degrades the signal-to-noise ratio (SNR). We have recently demonstrated that a multianode photomultiplier tube (MAPMT) placed in a descanned configuration can effectively collect scattered emission photons from each focus into their corresponding anodes significantly improving image SNR for highly scattering specimens. Unfortunately, a descanned MMM has a longer detection path resulting in substantial emission photon loss. Optical design constraints in a descanned geometry further results in significant optical aberrations especially for large field-of-view (FOV), high NA objectives. Here, we introduce a non-descanned MMM based on MAPMT that substantially overcomes most of these drawbacks. We show that we improve signal efficiency up to fourfold with limited image SNR degradation due to scattered emission photons. The excitation foci can also be spaced wider to cover the full FOV of the objective with minimal aberrations. The performance of this system is demonstrated by imaging interneuron morphological structures deep in the brains of living mice.
Collapse
Affiliation(s)
- Jae Won Cha
- Department of Mechanical Engineering, Massachusetts Institute of Technology , Cambridge, MA, USA
| | - Elijah Y S Yew
- Department of Mechanical Engineering, Massachusetts Institute of Technology , Cambridge, MA, USA
| | - Daekeun Kim
- Department of Mechanical Engineering, Dankook University , Korea
| | - Jaichandar Subramanian
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology , Cambridge, MA, USA
| | | | | |
Collapse
|
34
|
Song Q, Nakamura A, Hirosawa K, Isobe K, Midorikawa K, Kannari F. Two-dimensional spatiotemporal focusing of femtosecond pulses and its applications in microscopy. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2015; 86:083701. [PMID: 26329197 DOI: 10.1063/1.4927532] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
We demonstrate and theoretically analyze the two-dimensional spatiotemporal focusing of femtosecond pulses by utilizing a two-dimensional spectral disperser. Compared with spatiotemporal focusing with a diffraction grating, it can achieve widefield illumination with better sectioning ability for a multiphoton excitation process. By utilizing paraxial approximation, our analytical method improves the axial confinement ability and identifies that the free spectra range (FSR) of the two-dimensional spectral disperser affects the out-of-focus multiphoton excitation intensity due to the temporal self-imaging effect. Based on our numerical simulation, a FSR of 50 GHz is necessary to reduce the out-of-focus two-photon excitation by 2 orders of magnitude compared with that in a grating-based spatiotemporal focusing scheme for a 90-fs excitation laser pulse. We build a two-dimensional spatiotemporal focusing microscope using a virtually imaged phased array and achieve an axial resolution of 1.3 μm, which outperforms the resolution of conventional spatiotemporal focusing using a grating by a factor of 1.7, and demonstrate better image contrast inside a tissue-like phantom.
Collapse
Affiliation(s)
- Qiyuan Song
- Department of Electronics and Electrical Engineering, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan
| | - Aoi Nakamura
- Department of Electronics and Electrical Engineering, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan
| | - Kenichi Hirosawa
- Department of Electronics and Electrical Engineering, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan
| | - Keisuke Isobe
- RIKEN Center for Advanced Photonics, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Katsumi Midorikawa
- RIKEN Center for Advanced Photonics, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Fumihiko Kannari
- Department of Electronics and Electrical Engineering, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan
| |
Collapse
|
35
|
Singh A, McMullen JD, Doris EA, Zipfel WR. Comparison of objective lenses for multiphoton microscopy in turbid samples. BIOMEDICAL OPTICS EXPRESS 2015; 6:3113-27. [PMID: 26309771 PMCID: PMC4541535 DOI: 10.1364/boe.6.003113] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Revised: 07/20/2015] [Accepted: 07/20/2015] [Indexed: 05/20/2023]
Abstract
Optimization of illumination and detection optics is pivotal for multiphoton imaging in highly scattering tissue and the objective lens is the central component in both of these pathways. To better understand how basic lens parameters (NA, magnification, field number) affect fluorescence collection and image quality, a two-detector setup was used with a specialized sample cell to separate measurement of total excitation from epifluorescence collection. Our data corroborate earlier findings that low-mag lenses can be superior at collecting scattered photons, and we compare a set of commonly used multiphoton objective lenses in terms of their ability to collect scattered fluorescence, providing guidance for the design of multiphoton imaging systems. For example, our measurements of epi-fluorescence beam divergence in the presence of scattering reveal minimal beam broadening, indicating that often-advocated over-sized collection optics are not as advantageous as previously thought. These experiments also provide a framework for choosing objective lenses for multiphoton imaging by relating the results of our measurements to various design parameters of the objectives lenses used.
Collapse
Affiliation(s)
- Avtar Singh
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY 14853, USA
| | - Jesse D. McMullen
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY 14853, USA
| | - Eli A. Doris
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY 14853, USA
| | - Warren R. Zipfel
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY 14853, USA
- Department of Biomedical Engineering, Cornell University, Ithaca, NY 14853, USA
| |
Collapse
|
36
|
Young MD, Field JJ, Sheetz KE, Bartels RA, Squier J. A pragmatic guide to multiphoton microscope design. ADVANCES IN OPTICS AND PHOTONICS 2015; 7:276-378. [PMID: 27182429 PMCID: PMC4863715 DOI: 10.1364/aop.7.000276] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Multiphoton microscopy has emerged as a ubiquitous tool for studying microscopic structure and function across a broad range of disciplines. As such, the intent of this paper is to present a comprehensive resource for the construction and performance evaluation of a multiphoton microscope that will be understandable to the broad range of scientific fields that presently exploit, or wish to begin exploiting, this powerful technology. With this in mind, we have developed a guide to aid in the design of a multiphoton microscope. We discuss source selection, optical management of dispersion, image-relay systems with scan optics, objective-lens selection, single-element light-collection theory, photon-counting detection, image rendering, and finally, an illustrated guide for building an example microscope.
Collapse
Affiliation(s)
- Michael D. Young
- Center for Microintegrated Optics for Advanced Biological Control, Department of Physics, Colorado School of Mines, 1500 Illinois Street, Golden, Colorado 80401, USA
| | - Jeffrey J. Field
- W. M. Keck Laboratory for Raman Imaging of Cell-to-Cell Communications, Colorado State University, Fort Collins, Colorado 80523, USA
- Department of Electrical and Computer Engineering, Colorado State University, Fort Collins, Colorado 80523, USA
| | - Kraig E. Sheetz
- Photonics Research Center, Department of Physics and Nuclear Engineering, United States Military Academy, West Point, New York 10996, USA
| | - Randy A. Bartels
- W. M. Keck Laboratory for Raman Imaging of Cell-to-Cell Communications, Colorado State University, Fort Collins, Colorado 80523, USA
- Department of Electrical and Computer Engineering, Colorado State University, Fort Collins, Colorado 80523, USA
- School of Biomedical Engineering, Colorado State University, Fort Collins, Colorado 80523, USA
| | - Jeff Squier
- Center for Microintegrated Optics for Advanced Biological Control, Department of Physics, Colorado School of Mines, 1500 Illinois Street, Golden, Colorado 80401, USA
| |
Collapse
|
37
|
de Aguiar HB, Gasecka P, Brasselet S. Quantitative analysis of light scattering in polarization-resolved nonlinear microscopy. OPTICS EXPRESS 2015; 23:8960-8973. [PMID: 25968733 DOI: 10.1364/oe.23.008960] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Polarization resolved nonlinear microscopy (PRNM) is a powerful technique to gain microscopic structural information in biological media. However, deep imaging in a variety of biological specimens is hindered by light scattering phenomena, which not only degrades the image quality but also affects the polarization state purity. In order to quantify this phenomenon and give a framework for polarization resolved microscopy in thick scattering tissues, we develop a characterization methodology based on four wave mixing (FWM) process. More specifically, we take advantage of two unique features of FWM, meaning its ability to produce an intrinsic in-depth local coherent source and its capacity to quantify the presence of light depolarization in isotropic regions inside a sample. By exploring diverse experimental layouts in phantoms with different scattering properties, we study systematically the influence of scattering on the nonlinear excitation and emission processes. The results show that depolarization mechanisms for the nonlinearly generated photons are highly dependent on the scattering center size, the geometry used (epi/forward) and, most importantly, on the thickness of the sample. We show that the use of an un-analyzed detection makes the polarization-dependence read-out highly robust to scattering effects, even in regimes where imaging might be degraded. The effects are illustrated in polarization resolved imaging of myelin lipid organization in mouse spinal cords.
Collapse
|
38
|
Jung Y, Jeong S, Nayoun W, Ahn B, Kwag J, Geol Kim S, Kim S. Quantum dot imaging in the second near-infrared optical window: studies on reflectance fluorescence imaging depths by effective fluence rate and multiple image acquisition. JOURNAL OF BIOMEDICAL OPTICS 2015; 20:46012. [PMID: 25919424 DOI: 10.1117/1.jbo.20.4.046012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Accepted: 04/02/2015] [Indexed: 06/04/2023]
Abstract
Quantum dot (QD) imaging capability was investigated by the imaging depth at a near-infrared second optical window (SOW; 1000 to 1400 nm) using time-modulated pulsed laser excitations to control the effective fluence rate. Various media, such as liquid phantoms, tissues, and in vivo small animals, were used and the imaging depths were compared with our predicted values. The QD imaging depth under excitation of continuous 20 mW/cm(2) laser was determined to be 10.3 mm for 2 wt%hemoglobin phantom medium and 5.85 mm for 1 wt% intralipid phantom, which were extended by more than two times on increasing the effective fluence rate to 2000 mW/cm(2). Bovine liver and porcine skin tissues also showed similar enhancement in the contrast-to-noise ratio (CNR) values. A QD sample was inserted into the abdomen of a mouse.With a higher effective fluence rate, the CNR increased more than twofold and the QD sample became clearly visualized, which was completely undetectable under continuous excitation.Multiple acquisitions of QD images and averaging process pixel by pixel were performed to overcome the thermal noise issue of the detector in SOW, which yielded significant enhancement in the imaging capability, showing up to a 1.5 times increase in the CNR.
Collapse
Affiliation(s)
- Yebin Jung
- Pohang University of Science and Technology, Department of Chemistry, 77 Cheongam-ro, Nam-gu, Pohang 790-784, Republic of Korea
| | - Sanghwa Jeong
- Pohang University of Science and Technology, Department of Chemistry, 77 Cheongam-ro, Nam-gu, Pohang 790-784, Republic of Korea
| | - Won Nayoun
- Pohang University of Science and Technology, Department of Chemistry, 77 Cheongam-ro, Nam-gu, Pohang 790-784, Republic of Korea
| | - Boeun Ahn
- Pohang University of Science and Technology, Department of Chemistry, 77 Cheongam-ro, Nam-gu, Pohang 790-784, Republic of Korea
| | - Jungheon Kwag
- Pohang University of Science and Technology, School of Interdisciplinary Bioscience and Bioengineering, 77 Cheongam-ro, Nam-gu, Pohang 790-784, Republic of Korea
| | - Sang Geol Kim
- Kyungpook National University, School of Medicine, Department of Surgery, 680 Gukchaebosang-ro, Joong-gu, Daegu 700-422, Republic of Korea
| | - Sungjee Kim
- Pohang University of Science and Technology, Department of Chemistry, 77 Cheongam-ro, Nam-gu, Pohang 790-784, Republic of KoreabPohang University of Science and Technology, School of Interdisciplinary Bioscience and Bioengineering, 77 Cheongam-ro, Nam-gu
| |
Collapse
|
39
|
|
40
|
Fisher JAN, Salzberg BM. Two-Photon Excitation of Fluorescent Voltage-Sensitive Dyes: Monitoring Membrane Potential in the Infrared. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2015; 859:427-53. [PMID: 26238063 DOI: 10.1007/978-3-319-17641-3_17] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Functional imaging microscopy based on voltage-sensitive dyes (VSDs) has proven effective for revealing spatio-temporal patterns of activity in vivo and in vitro. Microscopy based on two-photon excitation of fluorescent VSDs offers the possibility of recording sub-millisecond membrane potential changes on micron length scales in cells that lie upwards of one millimeter below the brain's surface. Here we describe progress in monitoring membrane voltage using two-photon excitation (TPE) of VSD fluorescence, and detail an application of this emerging technology in which action potentials were recorded in single trials from individual mammalian nerve terminals in situ. Prospects for, and limitations of this method are reviewed.
Collapse
|
41
|
Turcotte R, Alt C, Mortensen LJ, Lin CP. Characterization of multiphoton microscopy in the bone marrow following intravital laser osteotomy. BIOMEDICAL OPTICS EXPRESS 2014; 5:3578-88. [PMID: 25360374 PMCID: PMC4206326 DOI: 10.1364/boe.5.003578] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Revised: 08/15/2014] [Accepted: 08/17/2014] [Indexed: 05/20/2023]
Abstract
The bone marrow is an important site where all blood cells are formed from hematopoietic stem cells and where hematologic malignancies such as leukemia emerge. It is also a frequent site for metastasis of solid tumors such as breast cancer and prostate cancer. Intravital microscopy is a powerful tool for studying the bone marrow with single cell and sub-cellular resolution. To improve optical access to this rich biological environment, plasma-mediated laser ablation with sub-microjoule femtosecond pulses was used to thin cortical bone. By locally removing a superficial layer of bone (local laser osteotomy), significant improvements in multiphoton imaging were observed in individual bone marrow compartments in vivo. This work demonstrates the utility of scanning laser ablation of hard tissue with sub-microjoule pulses as a preparatory step to imaging.
Collapse
Affiliation(s)
- Raphaël Turcotte
- Advanced Microscopy Program, Center for Systems Biology and Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, CPZN 8238, 185 Cambridge Street, Boston, MA 02114,
USA
- Department of Biomedical Engineering, Boston University, Boston, MA 02215,
USA
| | - Clemens Alt
- Advanced Microscopy Program, Center for Systems Biology and Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, CPZN 8238, 185 Cambridge Street, Boston, MA 02114,
USA
| | - Luke J. Mortensen
- Advanced Microscopy Program, Center for Systems Biology and Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, CPZN 8238, 185 Cambridge Street, Boston, MA 02114,
USA
| | - Charles P. Lin
- Advanced Microscopy Program, Center for Systems Biology and Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, CPZN 8238, 185 Cambridge Street, Boston, MA 02114,
USA
| |
Collapse
|
42
|
Du Le VN, Nie Z, Hayward JE, Farrell TJ, Fang Q. Measurements of extrinsic fluorescence in Intralipid and polystyrene microspheres. BIOMEDICAL OPTICS EXPRESS 2014; 5:2726-35. [PMID: 25136497 PMCID: PMC4133001 DOI: 10.1364/boe.5.002726] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Revised: 05/27/2014] [Accepted: 07/16/2014] [Indexed: 05/21/2023]
Abstract
The fluorescence of Intralipid and polystyrene microspheres with sphere diameter of 1 µm at a representative lipid and microsphere concentration for simulation of mucosal tissue scattering has not been a subject of extensive experimental study. In order to elucidate the quantitative relationship between lipid and microsphere concentration and the respective fluorescent intensity, the extrinsic fluorescence spectra between 360 nm and 650 nm (step size of 5 nm) were measured at different lipid concentrations (from 0.25% to 5%) and different microsphere concentrations (0.00364, 0.0073, 0.0131 spheres per cubic micrometer) using laser excitation at 355 nm with pulse energy of 2.8 µJ. Current findings indicated that Intralipid has a broadband emission between 360 and 650 nm with a primary peak at 500 nm and a secondary peak at 450 nm while polystyrene microspheres have a single peak at 500 nm. In addition, for similar scattering properties the fluorescence of Intralipid solutions is approximately three-fold stronger than that of the microsphere solutions. Furthermore, Intralipid phantoms with lipid concentrations ~2% (simulating the bottom layer of mucosa) produce up to seven times stronger fluorescent emission than phantoms with lipid concentration ~0.25% (simulating the top layer of mucosa). The fluoresence decays of Intralipid and microsphere solutions were also recorded for estimation of fluorescence lifetime.
Collapse
Affiliation(s)
- Vinh Nguyen Du Le
- Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ontario, Canada
| | - Zhaojun Nie
- School of Biomedical Engineering, McMaster University, Hamilton, Ontario, Canada
| | - Joseph E. Hayward
- Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ontario, Canada
| | - Thomas J. Farrell
- Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ontario, Canada
| | - Qiyin Fang
- School of Biomedical Engineering, McMaster University, Hamilton, Ontario, Canada
- Department of Engineering Physics, McMaster University, Hamilton, Ontario, Canada
| |
Collapse
|
43
|
Urban BE, Yi J, Yakovlev V, Zhang HF. Investigating femtosecond-laser-induced two-photon photoacoustic generation. JOURNAL OF BIOMEDICAL OPTICS 2014; 19:085001. [PMID: 25084119 PMCID: PMC4118047 DOI: 10.1117/1.jbo.19.8.085001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Accepted: 07/07/2014] [Indexed: 05/15/2023]
Abstract
We investigated two-photon absorption-based photoacoustic generation and compared it with corresponding photoluminescence emission. Experimental results revealed expected quadratic dependences on the incident optical fluence in both photoacoustic and photoluminescence processes. We also investigated the influence of optical scattering on the generation of two-photon photoacoustic and photoluminescence signals and found that photoacoustic signals attenuated more slowly than photoluminescence signals when the optical scattering coefficient was increased, which was attributed to a weaker ultrasonic attenuation than that the optical attenuation in the scattering medium. Finally, we showed three-dimensional two-photon photoacoustic imaging.
Collapse
Affiliation(s)
- Ben E. Urban
- Northwestern University, Department of Biomedical Engineering, Evanston, Illinois 60208, United States
| | - Ji Yi
- Northwestern University, Department of Biomedical Engineering, Evanston, Illinois 60208, United States
| | - Vladislav Yakovlev
- Texas A&M University, Department of Biomedical Engineering, College Station, Texas 77843, United States
| | - Hao F. Zhang
- Northwestern University, Department of Biomedical Engineering, Evanston, Illinois 60208, United States
- Address all correspondence to: Hao F. Zhang, E-mail:
| |
Collapse
|
44
|
Fouad A, Pfefer TJ, Chen CW, Gong W, Agrawal A, Tomlins PH, Woolliams PD, Drezek RA, Chen Y. Variations in optical coherence tomography resolution and uniformity: a multi-system performance comparison. BIOMEDICAL OPTICS EXPRESS 2014; 5:2066-81. [PMID: 25071949 PMCID: PMC4102349 DOI: 10.1364/boe.5.002066] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Revised: 05/30/2014] [Accepted: 05/30/2014] [Indexed: 05/12/2023]
Abstract
Point spread function (PSF) phantoms based on unstructured distributions of sub-resolution particles in a transparent matrix have been demonstrated as a useful tool for evaluating resolution and its spatial variation across image volumes in optical coherence tomography (OCT) systems. Measurements based on PSF phantoms have the potential to become a standard test method for consistent, objective and quantitative inter-comparison of OCT system performance. Towards this end, we have evaluated three PSF phantoms and investigated their ability to compare the performance of four OCT systems. The phantoms are based on 260-nm-diameter gold nanoshells, 400-nm-diameter iron oxide particles and 1.5-micron-diameter silica particles. The OCT systems included spectral-domain and swept source systems in free-beam geometries as well as a time-domain system in both free-beam and fiberoptic probe geometries. Results indicated that iron oxide particles and gold nanoshells were most effective for measuring spatial variations in the magnitude and shape of PSFs across the image volume. The intensity of individual particles was also used to evaluate spatial variations in signal intensity uniformity. Significant system-to-system differences in resolution and signal intensity and their spatial variation were readily quantified. The phantoms proved useful for identification and characterization of irregularities such as astigmatism. Our multi-system results provide evidence of the practical utility of PSF-phantom-based test methods for quantitative inter-comparison of OCT system resolution and signal uniformity.
Collapse
Affiliation(s)
- Anthony Fouad
- Center for Devices and Radiological Health, Food and Drug Administration, Silver Spring, MD, USA
- Fischell Department of Bioengineering, University of Maryland, College Park, MD, USA
| | - T. Joshua Pfefer
- Center for Devices and Radiological Health, Food and Drug Administration, Silver Spring, MD, USA
| | - Chao-Wei Chen
- Center for Devices and Radiological Health, Food and Drug Administration, Silver Spring, MD, USA
- Fischell Department of Bioengineering, University of Maryland, College Park, MD, USA
| | - Wei Gong
- Center for Devices and Radiological Health, Food and Drug Administration, Silver Spring, MD, USA
- Fischell Department of Bioengineering, University of Maryland, College Park, MD, USA
- College of Photonic and Electronic Engineering, Fujian Normal University, Fuzhou, Fujian, China
| | - Anant Agrawal
- Center for Devices and Radiological Health, Food and Drug Administration, Silver Spring, MD, USA
| | - Peter H. Tomlins
- Barts and The London School of Medicine and Dentistry, Queen Mary University of London, E1 1BB, London, UK
| | - Peter D. Woolliams
- Functional Materials Group, National Physical Laboratory, Teddington, UK
| | | | - Yu Chen
- Fischell Department of Bioengineering, University of Maryland, College Park, MD, USA
| |
Collapse
|
45
|
Ranasinghesagara JC, Hayakawa CK, Davis MA, Dunn AK, Potma EO, Venugopalan V. Rapid computation of the amplitude and phase of tightly focused optical fields distorted by scattering particles. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2014; 31:1520-30. [PMID: 25121440 PMCID: PMC4213127 DOI: 10.1364/josaa.31.001520] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
We develop an efficient method for accurately calculating the electric field of tightly focused laser beams in the presence of specific configurations of microscopic scatterers. This Huygens-Fresnel wave-based electric field superposition (HF-WEFS) method computes the amplitude and phase of the scattered electric field in excellent agreement with finite difference time-domain (FDTD) solutions of Maxwell's equations. Our HF-WEFS implementation is 2-4 orders of magnitude faster than the FDTD method and enables systematic investigations of the effects of scatterer size and configuration on the focal field. We demonstrate the power of the new HF-WEFS approach by mapping several metrics of focal field distortion as a function of scatterer position. This analysis shows that the maximum focal field distortion occurs for single scatterers placed below the focal plane with an offset from the optical axis. The HF-WEFS method represents an important first step toward the development of a computational model of laser-scanning microscopy of thick cellular/tissue specimens.
Collapse
Affiliation(s)
- Janaka C. Ranasinghesagara
- Department of Chemical Engineering and Materials Science, University of California, Irvine, California 92697, USA
- Laser Microbeam and Medical Program, Beckman Laser Institute, University of California, Irvine, California 92697, USA
| | - Carole K. Hayakawa
- Department of Chemical Engineering and Materials Science, University of California, Irvine, California 92697, USA
- Laser Microbeam and Medical Program, Beckman Laser Institute, University of California, Irvine, California 92697, USA
| | - Mitchell A. Davis
- Department of Biomedical Engineering, The University of Texas at Austin, Texas 78712, USA
| | - Andrew K. Dunn
- Department of Biomedical Engineering, The University of Texas at Austin, Texas 78712, USA
| | - Eric O. Potma
- Laser Microbeam and Medical Program, Beckman Laser Institute, University of California, Irvine, California 92697, USA
- Department of Chemistry, University of California, Irvine, California 92697, USA
| | - Vasan Venugopalan
- Department of Chemical Engineering and Materials Science, University of California, Irvine, California 92697, USA
- Laser Microbeam and Medical Program, Beckman Laser Institute, University of California, Irvine, California 92697, USA
- Corresponding author:
| |
Collapse
|
46
|
Dubach J, Vinegoni C, Mazitschek R, Fumene Feruglio P, Cameron L, Weissleder R. In vivo imaging of specific drug-target binding at subcellular resolution. Nat Commun 2014; 5:3946. [PMID: 24867710 PMCID: PMC4362617 DOI: 10.1038/ncomms4946] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Accepted: 04/23/2014] [Indexed: 01/11/2023] Open
Abstract
The possibility of measuring binding of small-molecule drugs to desired targets in live cells could provide a better understanding of drug action. However, current approaches mostly yield static data, require lysis or rely on indirect assays and thus often provide an incomplete understanding of drug action. Here, we present a multiphoton fluorescence anisotropy microscopy live cell imaging technique to measure and map drug-target interaction in real time at subcellular resolution. This approach is generally applicable using any fluorescently labelled drug and enables high-resolution spatial and temporal mapping of bound and unbound drug distribution. To illustrate our approach we measure intracellular target engagement of the chemotherapeutic Olaparib, a poly(ADP-ribose) polymerase inhibitor, in live cells and within a tumour in vivo. These results are the first generalizable approach to directly measure drug-target binding in vivo and present a promising tool to enhance understanding of drug activity.
Collapse
Affiliation(s)
- J.M. Dubach
- Center for System Biology, Massachusetts General Hospital and Harvard Medical School, Richard B. Simches Research Center, 185 Cambridge Street, Boston 02114, USA
| | - C. Vinegoni
- Center for System Biology, Massachusetts General Hospital and Harvard Medical School, Richard B. Simches Research Center, 185 Cambridge Street, Boston 02114, USA
| | - R. Mazitschek
- Center for System Biology, Massachusetts General Hospital and Harvard Medical School, Richard B. Simches Research Center, 185 Cambridge Street, Boston 02114, USA
| | - P. Fumene Feruglio
- Center for System Biology, Massachusetts General Hospital and Harvard Medical School, Richard B. Simches Research Center, 185 Cambridge Street, Boston 02114, USA
| | | | - R. Weissleder
- Center for System Biology, Massachusetts General Hospital and Harvard Medical School, Richard B. Simches Research Center, 185 Cambridge Street, Boston 02114, USA
| |
Collapse
|
47
|
Piston DW. Reply to “Letter to the editor: ‘Quantifying albumin permeability with multiphoton microscopy: why the difference?’”. Am J Physiol Renal Physiol 2014; 306:F1104-5. [DOI: 10.1152/ajprenal.00131.2014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- David W. Piston
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee; Department of Physics, Vanderbilt University, Nashville, Tennessee; and Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, Tennessee
| |
Collapse
|
48
|
Chronic cellular imaging of entire cortical columns in awake mice using microprisms. Neuron 2013; 80:900-13. [PMID: 24139817 DOI: 10.1016/j.neuron.2013.07.052] [Citation(s) in RCA: 145] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/29/2013] [Indexed: 11/22/2022]
Abstract
Two-photon imaging of cortical neurons in vivo has provided unique insights into the structure, function, and plasticity of cortical networks, but this method does not currently allow simultaneous imaging of neurons in the superficial and deepest cortical layers. Here, we describe a simple modification that enables simultaneous, long-term imaging of all cortical layers. Using a chronically implanted glass microprism in barrel cortex, we could image the same fluorescently labeled deep-layer pyramidal neurons across their entire somatodendritic axis for several months. We could also image visually evoked and endogenous calcium activity in hundreds of cell bodies or long-range axon terminals, across all six layers in visual cortex of awake mice. Electrophysiology and calcium imaging of evoked and endogenous activity near the prism face were consistent across days and comparable with previous observations. These experiments extend the reach of in vivo two-photon imaging to chronic, simultaneous monitoring of entire cortical columns.
Collapse
|
49
|
Imaging Condition Optimization in Multiphoton Microscopy of Three-Dimensional Collagen Fiber Structures. J CHIN CHEM SOC-TAIP 2013. [DOI: 10.1002/jccs.200400165] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
50
|
Adur J, DSouza-Li L, Pedroni MV, Steiner CE, Pelegati VB, de Thomaz AA, Carvalho HF, Cesar CL. The severity of Osteogenesis imperfecta and type I collagen pattern in human skin as determined by nonlinear microscopy: proof of principle of a diagnostic method. PLoS One 2013; 8:e69186. [PMID: 23869235 PMCID: PMC3711916 DOI: 10.1371/journal.pone.0069186] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Accepted: 06/09/2013] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND The confirmatory diagnosis of Osteogenesis Imperfecta (OI) requires invasive, commonly bone biopsy, time consuming and destructive methods. This paper proposes an alternative method using a combination of two-photon excitation fluorescence (TPEF) and second-harmonic generation (SHG) microscopies from easily obtained human skin biopsies. We show that this method can distinguish subtypes of human OI. METHODOLOGY/PRINCIPAL FINDINGS Different aspects of collagen microstructure of skin fresh biopsies and standard H&E-stained sections of normal and OI patients (mild and severe forms) were distinguished by TPEF and SHG images. Moreover, important differences between subtypes of OI were identified using different methods of quantification such as collagen density, ratio between collagen and elastic tissue, and gray-level co-occurrence matrix (GLCM) image-pattern analysis. Collagen density was lower in OI dermis, while the SHG/autofluorescence index of the dermis was significantly higher in OI as compared to that of the normal skin. We also showed that the energy value of GLCM texture analysis is useful to discriminate mild from severe OI and from normal skin. CONCLUSIONS/SIGNIFICANCE This work demonstrated that nonlinear microscopy techniques in combination with image-analysis approaches represent a powerful tool to investigate the collagen organization in skin dermis in patients with OI and has the potential to distinguish the different types of OI. The procedure outlined in this paper requires a skin biopsy, which is almost painless as compared to the bone biopsy commonly used in conventional methods. The data presented here complement existing clinical diagnostic techniques and can be used as a diagnostic procedure to confirm the disease, evaluate its severity and treatment efficacy.
Collapse
Affiliation(s)
- Javier Adur
- Biophotonic Group, Optics and Photonics Research Center (CEPOF), Institute of Physics "Gleb Wataghin," State University of Campinas - UNICAMP, Campinas, São Paulo, Brazil.
| | | | | | | | | | | | | | | |
Collapse
|