1
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Seo JP, Trippett JS, Huang Z, Lee S, Nouraein S, Wang RZ, Szablowski JO. Acoustically targeted measurement of transgene expression in the brain. SCIENCE ADVANCES 2024; 10:eadj7686. [PMID: 39110811 PMCID: PMC11305388 DOI: 10.1126/sciadv.adj7686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/21/2024] [Accepted: 06/28/2024] [Indexed: 08/10/2024]
Abstract
Gene expression is a critical component of brain physiology, but monitoring this expression in the living brain represents a major challenge. Here, we introduce a new paradigm called recovery of markers through insonation (REMIS) for noninvasive measurement of gene expression in the brain with cell type, spatial, and temporal specificity. Our approach relies on engineered protein markers that are produced in neurons but exit into the brain's interstitium. When ultrasound is applied to targeted brain regions, it opens the blood-brain barrier and releases these markers into the bloodstream. Once in blood, the markers can be readily detected using biochemical techniques. REMIS can noninvasively confirm gene delivery and measure endogenous signaling in specific brain sites through a simple insonation and a subsequent blood test. REMIS is reliable and demonstrated consistent improvement in recovery of markers from the brain into the blood. Overall, this work establishes a noninvasive, spatially specific method of monitoring gene delivery and endogenous signaling in the brain.
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Affiliation(s)
- Joon Pyung Seo
- Applied Physics Program, Rice University, Houston, TX, USA
| | | | - Zhimin Huang
- Department of Bioengineering, Rice University, Houston, TX, USA
| | - Sangsin Lee
- Department of Bioengineering, Rice University, Houston, TX, USA
| | - Shirin Nouraein
- Systems, Synthetic, and Physical Biology Program, Rice University, Houston, TX, USA
| | - Ryan Z. Wang
- Department of Bioengineering, Rice University, Houston, TX, USA
| | - Jerzy O. Szablowski
- Applied Physics Program, Rice University, Houston, TX, USA
- Department of Bioengineering, Rice University, Houston, TX, USA
- Systems, Synthetic, and Physical Biology Program, Rice University, Houston, TX, USA
- Rice Neuroengineering Initiative, Rice University, Houston, TX, USA
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2
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Chacko AN, Miller ADC, Dhanabalan KM, Mukherjee A. Exploring the potential of water channels for developing genetically encoded reporters and biosensors for diffusion-weighted MRI. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2024; 365:107743. [PMID: 39053029 DOI: 10.1016/j.jmr.2024.107743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2023] [Revised: 07/02/2024] [Accepted: 07/17/2024] [Indexed: 07/27/2024]
Abstract
Genetically encoded reporters for magnetic resonance imaging (MRI) offer a valuable technology for making molecular-scale measurements of biological processes within living organisms with high anatomical resolution and whole-organ coverage without relying on ionizing radiation. However, most MRI reporters rely on synthetic contrast agents, typically paramagnetic metals and metal complexes, which often need to be supplemented exogenously to create optimal contrast. To eliminate the need for synthetic contrast agents, we previously introduced aquaporin-1, a mammalian water channel, as a new reporter gene for the fully autonomous detection of genetically labeled cells using diffusion-weighted MRI. In this study, we aimed to expand the toolbox of diffusion-based genetic reporters by modulating aquaporin membrane trafficking and harnessing the evolutionary diversity of water channels across species. We identified a number of new water channels that functioned as diffusion-weighted reporter genes. In addition, we show that loss-of-function variants of yeast and human aquaporins can be leveraged to design first-in-class diffusion-based sensors for detecting the activity of a model protease within living cells.
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Affiliation(s)
- Asish N Chacko
- Department of Chemistry, University of California, Santa Barbara, CA 93106-5080, USA
| | - Austin D C Miller
- Biomolecular Science and Engineering Graduate Program, University of California, Santa Barbara, CA 93106-5080, USA
| | - Kaamini M Dhanabalan
- Department of Chemical Engineering, University of California, Santa Barbara, CA 93106-5080, USA
| | - Arnab Mukherjee
- Department of Chemistry, University of California, Santa Barbara, CA 93106-5080, USA; Biomolecular Science and Engineering Graduate Program, University of California, Santa Barbara, CA 93106-5080, USA; Department of Chemical Engineering, University of California, Santa Barbara, CA 93106-5080, USA; Department of Bioengineering, University of California, Santa Barbara, CA 93106-5080, USA.
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3
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Yun J, Huang Y, Miller ADC, Chang BL, Baldini L, Dhanabalan KM, Li E, Li H, Mukherjee A. Destabilized reporters for background-subtracted, chemically-gated, and multiplexed deep-tissue imaging. Chem Sci 2024; 15:11108-11121. [PMID: 39027298 PMCID: PMC11253201 DOI: 10.1039/d4sc00377b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Accepted: 05/23/2024] [Indexed: 07/20/2024] Open
Abstract
Tracking gene expression in deep tissues requires genetic reporters that can be unambiguously detected using tissue penetrant techniques. Magnetic resonance imaging (MRI) is uniquely suited for this purpose; however, there is a dearth of reporters that can be reliably linked to gene expression with minimal interference from background tissue signals. Here, we present a conceptually new method for generating background-subtracted, drug-gated, multiplex images of gene expression using MRI. Specifically, we engineered chemically erasable reporters consisting of a water channel, aquaporin-1, fused to destabilizing domains, which are stabilized by binding to cell-permeable small-molecule ligands. We showed that this approach allows for highly specific detection of gene expression through differential imaging. In addition, by engineering destabilized aquaporin-1 variants with orthogonal ligand requirements, it is possible to distinguish distinct subpopulations of cells in mixed cultures. Finally, we demonstrated this approach in a mouse tumor model through differential imaging of gene expression with minimal background.
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Affiliation(s)
- Jason Yun
- Department of Chemistry, University of California Santa Barbara CA 93106 USA
| | - Yimeng Huang
- Department of Chemistry, University of California Santa Barbara CA 93106 USA
| | - Austin D C Miller
- Biomolecular Science and Engineering Graduate Program, University of California Santa Barbara CA 93106 USA
| | - Brandon L Chang
- Department of Molecular, Cell, and Developmental Biology, University of California Santa Barbara CA 93106 USA
| | - Logan Baldini
- Department of Chemical Engineering, University of California Santa Barbara CA 93106 USA
| | - Kaamini M Dhanabalan
- Department of Chemical Engineering, University of California Santa Barbara CA 93106 USA
| | - Eugene Li
- Department of Chemical Engineering, University of California Santa Barbara CA 93106 USA
| | - Honghao Li
- Department of Chemistry, University of California Santa Barbara CA 93106 USA
| | - Arnab Mukherjee
- Department of Chemistry, University of California Santa Barbara CA 93106 USA
- Biomolecular Science and Engineering Graduate Program, University of California Santa Barbara CA 93106 USA
- Department of Chemical Engineering, University of California Santa Barbara CA 93106 USA
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4
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Ohlendorf R, Li N, Phi Van VD, Schwalm M, Ke Y, Dawson M, Jiang Y, Das S, Stallings B, Zheng WT, Jasanoff A. Imaging bioluminescence by detecting localized haemodynamic contrast from photosensitized vasculature. Nat Biomed Eng 2024; 8:775-786. [PMID: 38730257 DOI: 10.1038/s41551-024-01210-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Accepted: 03/30/2024] [Indexed: 05/12/2024]
Abstract
Bioluminescent probes are widely used to monitor biomedically relevant processes and cellular targets in living animals. However, the absorption and scattering of visible light by tissue drastically limit the depth and resolution of the detection of luminescence. Here we show that bioluminescent sources can be detected with magnetic resonance imaging by leveraging the light-mediated activation of vascular cells expressing a photosensitive bacterial enzyme that causes the conversion of bioluminescent emission into local changes in haemodynamic contrast. In the brains of rats with photosensitized vasculature, we used magnetic resonance imaging to volumetrically map bioluminescent xenografts and cell populations virally transduced to express luciferase. Detecting bioluminescence-induced haemodynamic signals from photosensitized vasculature will extend the applications of bioluminescent probes.
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Affiliation(s)
- Robert Ohlendorf
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
- Max Planck Institute for Biological Cybernetics, Tubingen, Germany
| | - Nan Li
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
- Advanced Imaging Research Center and Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Valerie Doan Phi Van
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Miriam Schwalm
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Yuting Ke
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Miranda Dawson
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Ying Jiang
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Sayani Das
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Brenna Stallings
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Wen Ting Zheng
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Alan Jasanoff
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA.
- Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
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5
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Huang Y, Chen X, Zhu Z, Mukherjee A. A Dual-Gene Reporter-Amplifier Architecture for Enhancing the Sensitivity of Molecular MRI by Water Exchange. Chembiochem 2024; 25:e202400087. [PMID: 38439618 DOI: 10.1002/cbic.202400087] [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: 01/30/2024] [Revised: 03/04/2024] [Accepted: 03/05/2024] [Indexed: 03/06/2024]
Abstract
The development of genetic reporters for magnetic resonance imaging (MRI) is essential for investigating biological functions in vivo. However, current MRI reporters have low sensitivity, making it challenging to create significant contrast against the tissue background, especially when only a small fraction of cells express the reporter. To overcome this limitation, we developed an approach for amplifying the sensitivity of molecular MRI by combining a chemogenetic contrast mechanism with a biophysical approach to increase water diffusion through the co-expression of a dual-gene construct comprising an organic anion transporting polypeptide, Oatp1b3, and a water channel, Aqp1. We first show that the expression of Aqp1 amplifies MRI contrast in cultured cells engineered to express Oatp1b3. We demonstrate that the contrast amplification is caused by Aqp1-driven increase in water exchange, which provides the gadolinium ions internalized by Oatp1b3-expressing cells with access to a larger water pool compared with exchange-limited conditions. We further show that our methodology allows cells to be detected using approximately 10-fold lower concentrations of gadolinium than that in the Aqp1-free scenario. Finally, we show that our approach enables the imaging of mixed-cell cultures containing a low fraction of Oatp1b3-labeled cells that are undetectable on the basis of Oatp1b3 expression alone.
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Affiliation(s)
- Yimeng Huang
- Department of Chemistry, University of California, Santa Barbara, CA 93106-5080
| | - Xinyue Chen
- Department of Molecular, Cellular, and Developmental Biology, University of California, Santa Barbara, CA 93106-5080
| | - Ziyue Zhu
- Department of Molecular, Cellular, and Developmental Biology, University of California, Santa Barbara, CA 93106-5080
| | - Arnab Mukherjee
- Department of Chemistry, University of California, Santa Barbara, CA 93106-5080
- Department of Molecular, Cellular, and Developmental Biology, University of California, Santa Barbara, CA 93106-5080
- Department of Chemical Engineering, University of California, Santa Barbara, CA 93106-5080
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6
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Miller ADC, Chowdhury SP, Hanson HW, Linderman SK, Ghasemi HI, Miller WD, Morrissey MA, Richardson CD, Gardner BM, Mukherjee A. Engineering water exchange is a safe and effective method for magnetic resonance imaging in diverse cell types. J Biol Eng 2024; 18:30. [PMID: 38649904 PMCID: PMC11035135 DOI: 10.1186/s13036-024-00424-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Accepted: 04/08/2024] [Indexed: 04/25/2024] Open
Abstract
Aquaporin-1 (Aqp1), a water channel, has garnered significant interest for cell-based medicine and in vivo synthetic biology due to its ability to be genetically encoded to produce magnetic resonance signals by increasing the rate of water diffusion in cells. However, concerns regarding the effects of Aqp1 overexpression and increased membrane diffusivity on cell physiology have limited its widespread use as a deep-tissue reporter. In this study, we present evidence that Aqp1 generates strong diffusion-based magnetic resonance signals without adversely affecting cell viability or morphology in diverse cell lines derived from mice and humans. Our findings indicate that Aqp1 overexpression does not induce ER stress, which is frequently associated with heterologous expression of membrane proteins. Furthermore, we observed that Aqp1 expression had no detrimental effects on native biological activities, such as phagocytosis, immune response, insulin secretion, and tumor cell migration in the analyzed cell lines. These findings should serve to alleviate any lingering safety concerns regarding the utilization of Aqp1 as a genetic reporter and should foster its broader application as a noninvasive reporter for in vivo studies.
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Affiliation(s)
- Austin D C Miller
- Biomolecular Science and Engineering Graduate Program, University of California, Santa Barbara, CA, 93106, USA
| | - Soham P Chowdhury
- Department of Molecular, Cellular, and Developmental Biology, University of California, Santa Barbara, CA, 93106, USA
| | - Hadley W Hanson
- Biomolecular Science and Engineering Graduate Program, University of California, Santa Barbara, CA, 93106, USA
| | - Sarah K Linderman
- Department of Molecular, Cellular, and Developmental Biology, University of California, Santa Barbara, CA, 93106, USA
| | - Hannah I Ghasemi
- Department of Molecular, Cellular, and Developmental Biology, University of California, Santa Barbara, CA, 93106, USA
| | - Wyatt D Miller
- Biomolecular Science and Engineering Graduate Program, University of California, Santa Barbara, CA, 93106, USA
| | - Meghan A Morrissey
- Department of Molecular, Cellular, and Developmental Biology, University of California, Santa Barbara, CA, 93106, USA
| | - Chris D Richardson
- Department of Molecular, Cellular, and Developmental Biology, University of California, Santa Barbara, CA, 93106, USA
| | - Brooke M Gardner
- Department of Molecular, Cellular, and Developmental Biology, University of California, Santa Barbara, CA, 93106, USA
| | - Arnab Mukherjee
- Biomolecular Science and Engineering Graduate Program, University of California, Santa Barbara, CA, 93106, USA.
- Department of Chemical Engineering, University of California, Santa Barbara, CA, 93106, USA.
- Department of Bioengineering, University of California, Santa Barbara, CA, 93106, USA.
- Department of Chemistry, University of California, Santa Barbara, CA, 93106, USA.
- Neuroscience Research Institute, University of California, Santa Barbara, CA, 93106, USA.
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7
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Huang Y, Chen X, Zhu Z, Mukherjee A. A dual-gene reporter-amplifier architecture for enhancing the sensitivity of molecular MRI by water exchange. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.22.576672. [PMID: 38328134 PMCID: PMC10849537 DOI: 10.1101/2024.01.22.576672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
Abstract
The development of genetic reporters for magnetic resonance imaging (MRI) is essential for investigating biological functions in intact animals. However, current MRI reporters have low sensitivity, making it challenging to create significant contrast against the tissue background, especially when only a small percentage of cells express the reporter. To overcome this limitation, we developed an approach that amplifies signals by co-expressing an MRI reporter gene, Oatp1b3, with a water channel, aquaporin-1 (Aqp1). We first show that the expression of Aqp1 amplifies the paramagnetic relaxation effect of Oatp1b3 by facilitating transmembrane water exchange. This mechanism provides Oatp1b3-expressing cells with access to a larger water pool compared with typical exchange-limited conditions. We further demonstrated that our methodology allows dual-labeled cells to be detected using approximately 10-fold lower concentrations of contrast agent than that in the Aqp1-free scenario. Finally, we show that our approach enables the imaging of mixed-cell populations containing a low fraction of Oatp1b3-labeled cells that are otherwise undetectable based on Oatp1b3 expression alone.
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Affiliation(s)
| | - Xinyue Chen
- Department of Molecular, Cellular, and Developmental Biology
| | - Ziyue Zhu
- Department of Molecular, Cellular, and Developmental Biology
| | - Arnab Mukherjee
- Department of Chemistry
- Department of Molecular, Cellular, and Developmental Biology
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8
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Chacko AN, Miller AD, Dhanabalan KM, Mukherjee A. Exploring the potential of water channels for developing MRI reporters and sensors without the need for exogenous contrast agents. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.21.576580. [PMID: 38328035 PMCID: PMC10849501 DOI: 10.1101/2024.01.21.576580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
Abstract
Genetically encoded reporters for magnetic resonance imaging (MRI) offer a valuable technology for making molecular-scale measurements of biological processes within living organisms with high anatomical resolution and whole-organ coverage without relying on ionizing radiation. However, most MRI reporters rely on contrast agents, typically paramagnetic metals and metal complexes, which often need to be supplemented exogenously to create optimal contrast. To eliminate the need for contrast agents, we previously introduced aquaporin-1, a mammalian water channel, as a new reporter gene for the fully autonomous detection of genetically labeled cells using diffusion-weighted MRI. In this study, we aimed to expand the toolbox of diffusion-based genetic reporters by modulating aquaporin membrane trafficking and harnessing the evolutionary diversity of water channels across species. We identified a number of new water channels that functioned as diffusion-weighted reporter genes. In addition, we show that loss-of-function variants of yeast and human aquaporins can be leveraged to design first-in-class diffusion-based sensors for detecting the activity of a model protease within living cells.
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Affiliation(s)
| | | | | | - Arnab Mukherjee
- Department of Chemistry
- Biomolecular Science and Engineering Graduate Program
- Department of Chemical Engineering
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9
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Miller ADC, Chowdhury SP, Hanson HW, Linderman SK, Ghasemi HI, Miller WD, Morrissey MA, Richardson CD, Gardner BM, Mukherjee A. Engineering water exchange is a safe and effective method for magnetic resonance imaging in diverse cell types. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.07.566095. [PMID: 37986852 PMCID: PMC10659288 DOI: 10.1101/2023.11.07.566095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2023]
Abstract
Aquaporin-1 (Aqp1), a water channel, has garnered significant interest for cell-based medicine and in vivo synthetic biology due to its ability to be genetically encoded to produce magnetic resonance signals by increasing the rate of water diffusion in cells. However, concerns regarding the effects of Aqp1 overexpression and increased membrane diffusivity on cell physiology have limited its widespread use as a deep-tissue reporter. In this study, we present evidence that Aqp1 generates strong diffusion-based magnetic resonance signals without adversely affecting cell viability or morphology in diverse cell lines derived from mice and humans. Our findings indicate that Aqp1 overexpression does not induce ER stress, which is frequently associated with heterologous expression of membrane proteins. Furthermore, we observed that Aqp1 expression had no detrimental effects on native biological activities, such as phagocytosis, immune response, insulin secretion, and tumor cell migration in the analyzed cell lines. These findings should serve to alleviate any lingering safety concerns regarding the utilization of Aqp1 as a genetic reporter and should foster its broader application as a noninvasive reporter for in vivo studies.
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Affiliation(s)
- Austin D C Miller
- Biomolecular Science and Engineering Graduate Program, University of California, Santa Barbara, CA 93106, USA
| | - Soham P Chowdhury
- Department of Molecular, Cellular, and Developmental Biology, University of California, Santa Barbara, CA 93106, USA
| | - Hadley W Hanson
- Biomolecular Science and Engineering Graduate Program, University of California, Santa Barbara, CA 93106, USA
| | - Sarah K Linderman
- Department of Molecular, Cellular, and Developmental Biology, University of California, Santa Barbara, CA 93106, USA
| | - Hannah I Ghasemi
- Department of Molecular, Cellular, and Developmental Biology, University of California, Santa Barbara, CA 93106, USA
| | - Wyatt D Miller
- Biomolecular Science and Engineering Graduate Program, University of California, Santa Barbara, CA 93106, USA
| | - Meghan A Morrissey
- Department of Molecular, Cellular, and Developmental Biology, University of California, Santa Barbara, CA 93106, USA
| | - Chris D Richardson
- Department of Molecular, Cellular, and Developmental Biology, University of California, Santa Barbara, CA 93106, USA
| | - Brooke M Gardner
- Department of Molecular, Cellular, and Developmental Biology, University of California, Santa Barbara, CA 93106, USA
| | - Arnab Mukherjee
- Biomolecular Science and Engineering Graduate Program, University of California, Santa Barbara, CA 93106, USA
- Department of Chemical Engineering, University of California, Santa Barbara, CA 93106, USA
- Department of Bioengineering, University of California, Santa Barbara, CA 93106, USA
- Department of Chemistry, University of California, Santa Barbara, CA 93106, USA
- Neuroscience Research Institute, University of California, Santa Barbara, CA 93106, USA
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10
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Yun J, Baldini L, Huang Y, Li E, Li H, Chacko AN, Miller AD, Wan J, Mukherjee A. Engineering ligand stabilized aquaporin reporters for magnetic resonance imaging. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.02.543364. [PMID: 37333371 PMCID: PMC10274688 DOI: 10.1101/2023.06.02.543364] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2023]
Abstract
Imaging transgene expression in live tissues requires reporters that are detectable with deeply penetrant modalities, such as magnetic resonance imaging (MRI). Here, we show that LSAqp1, a water channel engineered from aquaporin-1, can be used to create background-free, drug-gated, and multiplex images of gene expression using MRI. LSAqp1 is a fusion protein composed of aquaporin-1 and a degradation tag that is sensitive to a cell-permeable ligand, which allows for dynamic small molecule modulation of MRI signals. LSAqp1 improves specificity for imaging gene expression by allowing reporter signals to be conditionally activated and distinguished from the tissue background by difference imaging. In addition, by engineering destabilized aquaporin-1 variants with different ligand requirements, it is possible to image distinct cell types simultaneously. Finally, we expressed LSAqp1 in a tumor model and showed successful in vivo imaging of gene expression without background activity. LSAqp1 provides a conceptually unique approach to accurately measure gene expression in living organisms by combining the physics of water diffusion and biotechnology tools to control protein stability.
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Affiliation(s)
- Jason Yun
- Department of Chemistry, University of California, Santa Barbara, CA 93106, USA
| | - Logan Baldini
- Department of Chemical Engineering, University of California, Santa Barbara, CA 93106, USA
| | - Yimeng Huang
- Department of Chemistry, University of California, Santa Barbara, CA 93106, USA
| | - Eugene Li
- Department of Chemical Engineering, University of California, Santa Barbara, CA 93106, USA
| | - Honghao Li
- Department of Chemistry, University of California, Santa Barbara, CA 93106, USA
| | - Asish N. Chacko
- Department of Chemistry, University of California, Santa Barbara, CA 93106, USA
| | - Austin D.C. Miller
- Biomolecular Science and Engineering, University of California, Santa Barbara, CA 93106, USA
| | - Jinyang Wan
- Department of Chemistry, University of California, Santa Barbara, CA 93106, USA
| | - Arnab Mukherjee
- Department of Chemistry, University of California, Santa Barbara, CA 93106, USA
- Department of Chemical Engineering, University of California, Santa Barbara, CA 93106, USA
- Biomolecular Science and Engineering, University of California, Santa Barbara, CA 93106, USA
- Biological Engineering, University of California, Santa Barbara, CA 93106, USA
- Neuroscience Research Institute, University of California, Santa Barbara, CA 93106, USA
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11
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Seo JP, Trippett JS, Huang Z, Wang RZ, Lee S, Szablowski JO. Acoustically-Targeted Measurement of Transgene Expression in the Brain. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.23.541868. [PMID: 37292585 PMCID: PMC10245922 DOI: 10.1101/2023.05.23.541868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Gene expression is a critical component of brain physiology and activity, but monitoring this expression in the living brain represents a significant challenge. Here, we introduce a new paradigm called Recovery of Markers through InSonation (REMIS) for noninvasive measurement of gene expression in the brain with cell-type, spatial, and temporal specificity. Our approach relies on engineered protein markers that are designed to be expressed in neurons and exit into the interstitium. By applying ultrasound to targeted brain regions, these markers are released into the bloodstream, where they can be readily detected using biochemical techniques. REMIS can noninvasively confirm gene delivery and measure endogenous signaling in specific brain sites through a simple insonation and a subsequent blood test. Using REMIS, we successfully measured chemogenetic induction of neuronal activity in ultrasound-tar-geted brain regions. REMIS recovery of markers is reliable and demonstrated improved recovery of markers from the brain into the blood in every tested animal. Overall, our work establishes a noninvasive, spatially-specific means of monitoring gene delivery outcomes and endogenous signaling in mammalian brains, opening up possibilities for brain research and noninvasive monitoring of gene therapies in the brain.
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12
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Liu Z, Zhu Y, Zhang L, Jiang W, Liu Y, Tang Q, Cai X, Li J, Wang L, Tao C, Yin X, Li X, Hou S, Jiang D, Liu K, Zhou X, Zhang H, Liu M, Fan C, Tian Y. Structural and functional imaging of brains. Sci China Chem 2022; 66:324-366. [PMID: 36536633 PMCID: PMC9753096 DOI: 10.1007/s11426-022-1408-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 09/28/2022] [Indexed: 12/23/2022]
Abstract
Analyzing the complex structures and functions of brain is the key issue to understanding the physiological and pathological processes. Although neuronal morphology and local distribution of neurons/blood vessels in the brain have been known, the subcellular structures of cells remain challenging, especially in the live brain. In addition, the complicated brain functions involve numerous functional molecules, but the concentrations, distributions and interactions of these molecules in the brain are still poorly understood. In this review, frontier techniques available for multiscale structure imaging from organelles to the whole brain are first overviewed, including magnetic resonance imaging (MRI), computed tomography (CT), positron emission tomography (PET), serial-section electron microscopy (ssEM), light microscopy (LM) and synchrotron-based X-ray microscopy (XRM). Specially, XRM for three-dimensional (3D) imaging of large-scale brain tissue with high resolution and fast imaging speed is highlighted. Additionally, the development of elegant methods for acquisition of brain functions from electrical/chemical signals in the brain is outlined. In particular, the new electrophysiology technologies for neural recordings at the single-neuron level and in the brain are also summarized. We also focus on the construction of electrochemical probes based on dual-recognition strategy and surface/interface chemistry for determination of chemical species in the brain with high selectivity and long-term stability, as well as electrochemophysiological microarray for simultaneously recording of electrochemical and electrophysiological signals in the brain. Moreover, the recent development of brain MRI probes with high contrast-to-noise ratio (CNR) and sensitivity based on hyperpolarized techniques and multi-nuclear chemistry is introduced. Furthermore, multiple optical probes and instruments, especially the optophysiological Raman probes and fiber Raman photometry, for imaging and biosensing in live brain are emphasized. Finally, a brief perspective on existing challenges and further research development is provided.
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Affiliation(s)
- Zhichao Liu
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, 200241 China
| | - Ying Zhu
- Interdisciplinary Research Center, Shanghai Synchrotron Radiation Facility, Zhangjiang Laboratory, Shanghai Advanced Research Institute, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, 201210 China
| | - Liming Zhang
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, 200241 China
| | - Weiping Jiang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Chinese Academy of Sciences, Wuhan National Laboratory for Optoelectronics, Wuhan, 430071 China
| | - Yawei Liu
- State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022 China
| | - Qiaowei Tang
- Interdisciplinary Research Center, Shanghai Synchrotron Radiation Facility, Zhangjiang Laboratory, Shanghai Advanced Research Institute, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, 201210 China
| | - Xiaoqing Cai
- Interdisciplinary Research Center, Shanghai Synchrotron Radiation Facility, Zhangjiang Laboratory, Shanghai Advanced Research Institute, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, 201210 China
| | - Jiang Li
- Interdisciplinary Research Center, Shanghai Synchrotron Radiation Facility, Zhangjiang Laboratory, Shanghai Advanced Research Institute, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, 201210 China
| | - Lihua Wang
- Interdisciplinary Research Center, Shanghai Synchrotron Radiation Facility, Zhangjiang Laboratory, Shanghai Advanced Research Institute, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, 201210 China
| | - Changlu Tao
- Interdisciplinary Center for Brain Information, Brain Cognition and Brain Disease Institute, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Faculty of Life and Health Sciences, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055 China
| | | | - Xiaowei Li
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, 200240 China
| | - Shangguo Hou
- Institute of Systems and Physical Biology, Shenzhen Bay Laboratory, Shenzhen, 518055 China
| | - Dawei Jiang
- Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022 China
| | - Kai Liu
- Department of Chemistry, Tsinghua University, Beijing, 100084 China
| | - Xin Zhou
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Chinese Academy of Sciences, Wuhan National Laboratory for Optoelectronics, Wuhan, 430071 China
| | - Hongjie Zhang
- State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022 China
- Department of Chemistry, Tsinghua University, Beijing, 100084 China
| | - Maili Liu
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Chinese Academy of Sciences, Wuhan National Laboratory for Optoelectronics, Wuhan, 430071 China
| | - Chunhai Fan
- School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformative Molecules, Institute of Translational Medicine, Shanghai Jiao Tong University, Shanghai, 200240 China
| | - Yang Tian
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, 200241 China
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Barandov A, Ghosh S, Jasanoff A. Probing nitric oxide signaling using molecular MRI. Free Radic Biol Med 2022; 191:241-248. [PMID: 36084790 PMCID: PMC10204116 DOI: 10.1016/j.freeradbiomed.2022.08.042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 08/27/2022] [Accepted: 08/31/2022] [Indexed: 11/18/2022]
Abstract
Wide field measurements of nitric oxide (NO) signaling could help understand and diagnose the many physiological processes in which NO plays a key role. Magnetic resonance imaging (MRI) can support particularly powerful approaches for this purpose if equipped with molecular probes sensitized to NO and NO-associated targets. In this review, we discuss the development of MRI-detectable probes that could enable studies of nitrergic signaling in animals and potentially human subjects. Major families of probes include contrast agents designed to capture and report integrated NO levels directly, as well as molecules that respond to or emulate the activity of nitric oxide synthase enzymes. For each group, we outline the relevant molecular mechanisms and discuss results that have been obtained in vitro and in animals. The most promising in vivo data described to date have been acquired using NO capture-based relaxation agents and using engineered nitric oxide synthases that provide hemodynamic readouts of NO signaling pathway activation. These advances establish a beachhead for ongoing efforts to improve the sensitivity, specificity, and clinical applicability of NO-related molecular MRI technology.
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Affiliation(s)
- Ali Barandov
- Department of Biological Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA, 02139, USA
| | - Souparno Ghosh
- Department of Biological Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA, 02139, USA
| | - Alan Jasanoff
- Department of Biological Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA, 02139, USA; Department of Brain & Cognitive Sciences, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA, 02139, USA; Department of Nuclear Science & Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA, 02139, USA.
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14
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X marks the spot: mapping the brain with EEG and MRI. Biotechniques 2022; 73:110-112. [PMID: 36073172 DOI: 10.2144/btn-2022-0088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
In this month's Technology News, we go back to the basics of two neuroimaging techniques and look at how these have been advanced in 2022.
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Yun J, Baldini M, Chowdhury R, Mukherjee A. Designing Protein-Based Probes for Sensing Biological Analytes with Magnetic Resonance Imaging. ANALYSIS & SENSING 2022; 2:e202200019. [PMID: 37409177 PMCID: PMC10321474 DOI: 10.1002/anse.202200019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/07/2023]
Abstract
Genetically encoded sensors provide unique advantages for monitoring biological analytes with molecular and cellular-level specificity. While sensors derived from fluorescent proteins represent staple tools in biological imaging, these probes are limited to optically accessible preparations owing to physical curbs on light penetration. In contrast to optical methods, magnetic resonance imaging (MRI) may be used to noninvasively look inside intact organisms at any arbitrary depth and over large fields of view. These capabilities have spurred the development of innovative methods to connect MRI readouts with biological targets using protein-based probes that are in principle genetically encodable. Here, we highlight the state-of-the-art in MRI-based biomolecular sensors, focusing on their physical mechanisms, quantitative characteristics, and biological applications. We also describe how innovations in reporter gene technology are creating new opportunities to engineer MRI sensors that are sensitive to dilute biological targets.
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Affiliation(s)
- Jason Yun
- Department of Chemistry, University of California, Santa Barbara, CA 93106, USA
| | - Michelle Baldini
- Department of Chemical Engineering, University of California, Santa Barbara, CA 93106, USA
| | - Rochishnu Chowdhury
- Mechanical Engineering, University of California, Santa Barbara, CA 93106, USA
| | - Arnab Mukherjee
- Department of Chemical Engineering, University of California, Santa Barbara, CA 93106, USA
- Department of Chemistry, University of California, Santa Barbara, CA 93106, USA
- Biomolecular Science and Engineering, University of California, Santa Barbara, CA 93106, USA
- Neuroscience Research Institute, University of California, Santa Barbara, CA 93106, USA
- Center for BioEngineering, University of California, Santa Barbara, CA 93106, USA
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16
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Zheng N, Li M, Wu Y, Kaewborisuth C, Li Z, Gui Z, Wu J, Cai A, Lin K, Su KP, Xiang H, Tian X, Manyande A, Xu F, Wang J. A novel technology for in vivo detection of cell type-specific neural connection with AQP1-encoding rAAV2-retro vector and metal-free MRI. Neuroimage 2022; 258:119402. [PMID: 35732245 DOI: 10.1016/j.neuroimage.2022.119402] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 06/18/2022] [Accepted: 06/18/2022] [Indexed: 01/10/2023] Open
Abstract
A mammalian brain contains numerous neurons with distinct cell types for complex neural circuits. Virus-based circuit tracing tools are powerful in tracking the interaction among the different brain regions. However, detecting brain-wide neural networks in vivo remains challenging since most viral tracing systems rely on postmortem optical imaging. We developed a novel approach that enables in vivo detection of brain-wide neural connections based on metal-free magnetic resonance imaging (MRI). The recombinant adeno-associated virus (rAAV) with retrograde ability, the rAAV2-retro, encoding the human water channel aquaporin 1 (AQP1) MRI reporter gene was generated to label neural connections. The mouse was micro-injected with the virus at the Caudate Putamen (CPU) region and subjected to detection with Diffusion-weighted MRI (DWI). The prominent structure of the CPU-connected network was clearly defined. In combination with a Cre-loxP system, rAAV2-retro expressing Cre-dependent AQP1 provides a CPU-connected network of specific type neurons. Here, we established a sensitive, metal-free MRI-based strategy for in vivo detection of cell type-specific neural connections in the whole brain, which could visualize the dynamic changes of neural networks in rodents and potentially in non-human primates.
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Affiliation(s)
- Ning Zheng
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences-Wuhan National Laboratory for Optoelectronics, Wuhan Institute of Physics and Mathematics, Wuhan 430071, China
| | - Mei Li
- The Brain Cognition and Brain Disease Institute (BCBDI), NMPA Key Laboratory for Research and Evaluation of Viral Vector Technology in Cell and Gene Therapy Medicinal Products, Shenzhen Key Laboratory of Viral Vectors for Biomedicine, Shenzhen Institute of Advanced Technology, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Yang Wu
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences-Wuhan National Laboratory for Optoelectronics, Wuhan Institute of Physics and Mathematics, Wuhan 430071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Challika Kaewborisuth
- Virology and Cell Technology Research Team, National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency (NSTDA), Pathumthani 12120, Thailand
| | - Zhen Li
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Zhu Gui
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences-Wuhan National Laboratory for Optoelectronics, Wuhan Institute of Physics and Mathematics, Wuhan 430071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jinfeng Wu
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences-Wuhan National Laboratory for Optoelectronics, Wuhan Institute of Physics and Mathematics, Wuhan 430071, China
| | - Aoling Cai
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences-Wuhan National Laboratory for Optoelectronics, Wuhan Institute of Physics and Mathematics, Wuhan 430071, China
| | - Kangguang Lin
- Department of Affective Disorders, The Affiliated Brain Hospital of Guangzhou Medical University, Guangzhou, China
| | - Kuan-Pin Su
- Department of Psychiatry, China Medical University Hospital, Taichung City, Taiwan, China
| | - Hongbing Xiang
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Xuebi Tian
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Anne Manyande
- School of Human and Social Sciences, University of West London, Middlesex, TW8 9GA, UK
| | - Fuqiang Xu
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences-Wuhan National Laboratory for Optoelectronics, Wuhan Institute of Physics and Mathematics, Wuhan 430071, China; The Brain Cognition and Brain Disease Institute (BCBDI), NMPA Key Laboratory for Research and Evaluation of Viral Vector Technology in Cell and Gene Therapy Medicinal Products, Shenzhen Key Laboratory of Viral Vectors for Biomedicine, Shenzhen Institute of Advanced Technology, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Chinese Academy of Sciences, Shenzhen 518055, China; University of Chinese Academy of Sciences, Beijing 100049, China; Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai 200031, China
| | - Jie Wang
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences-Wuhan National Laboratory for Optoelectronics, Wuhan Institute of Physics and Mathematics, Wuhan 430071, China; Institute of Neuroscience and Brain Diseases, Xiangyang Central Hospital, Affiliated Hospital of Hubei University of Arts and Science, Xiangyang, Hubei, China.
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