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Oeffinger BE, Stanczak M, Lepore AC, Eisenbrey JR, Wheatley MA. Determining Ultrasound Parameters for Bursting Polymer Microbubbles for Future Use in Spinal Cord Injury. ULTRASOUND IN MEDICINE & BIOLOGY 2024; 50:888-897. [PMID: 38519360 DOI: 10.1016/j.ultrasmedbio.2024.02.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 02/14/2024] [Accepted: 02/22/2024] [Indexed: 03/24/2024]
Abstract
OBJECTIVE We believe our poly(lactic acid) (PLA) microbubbles are well suited for therapeutic delivery to spinal cord injury (SCI) using ultrasound-triggered bursting. We investigated the feasibility of clinical ultrasound bursting in situ, the optimal bursting parameters in vitro and the loading and release of a model bio-active DNA. METHODS Microbubbles were tested using clinical ultrasound in a rat cadaver SCI model. Burst pressure thresholds were determined using the change in enhancement after ultrasound exposure. Resonance frequency, acoustic enhancement, sizing and morphology were evaluated by comparing two microbubble porogens, ammonium carbonate and ammonium carbamate. Oligonucleotides were loaded into the shell and released using the found optimized ultrasound bursting parameters. RESULTS In situ imaging and bursting were successful. In vitro bursting thresholds using frequencies 1, 2.25 and 5 MHz were identified between peak negative pressures 0.2 and 0.5 MPa, believed to be safe for spinal cord. The pressure threshold decreased with decreasing frequencies. PLA bursting was optimized near the resonance frequency of 2.5 to 3.0 MHz using 2.25 MHz and not at lower frequencies. PLA microbubbles, initially with a mean size of approximately 2 µm, remained in one piece, collapsed to between 0.5 and 1 µm and did not fragment. Significantly more oligonucleotide was released after ultrasound bursting of loaded microbubbles. Microbubble-sized debris was detected when using ammonium carbamate, leading to inaccurate microbubble concentration measurements. CONCLUSION PLA microbubbles made with ammonium carbonate and burst at appropriate parameters have the potential to safely improve intrathecal therapeutic delivery to SCI using targeted ultrasound.
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Affiliation(s)
- Brian E Oeffinger
- School of Biomedical Engineering, Science and Health Systems, Drexel University, Philadelphia, PA, USA
| | - Maria Stanczak
- Department of Radiology, Thomas Jefferson University, Philadelphia, PA, USA
| | - Angelo C Lepore
- Department of Neuroscience, Vickie and Jack Farber Institute for Neuroscience, Sidney Kimmel Medical Collage at Thomas Jefferson University, Philadelphia, PA, USA
| | - John R Eisenbrey
- Department of Radiology, Thomas Jefferson University, Philadelphia, PA, USA
| | - Margaret A Wheatley
- School of Biomedical Engineering, Science and Health Systems, Drexel University, Philadelphia, PA, USA.
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2
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Moura MM, Monteiro A, Salgado AJ, Silva NA, Monteiro S. Disrupted autonomic pathways in spinal cord injury: Implications for the immune regulation. Neurobiol Dis 2024; 195:106500. [PMID: 38614275 DOI: 10.1016/j.nbd.2024.106500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 03/25/2024] [Accepted: 04/04/2024] [Indexed: 04/15/2024] Open
Abstract
Spinal Cord Injury (SCI) disrupts critical autonomic pathways responsible for the regulation of the immune function. Consequently, individuals with SCI often exhibit a spectrum of immune dysfunctions ranging from the development of damaging pro-inflammatory responses to severe immunosuppression. Thus, it is imperative to gain a more comprehensive understanding of the extent and mechanisms through which SCI-induced autonomic dysfunction influences the immune response. In this review, we provide an overview of the anatomical organization and physiology of the autonomic nervous system (ANS), elucidating how SCI impacts its function, with a particular focus on lymphoid organs and immune activity. We highlight recent advances in understanding how intraspinal plasticity that follows SCI may contribute to aberrant autonomic activity in lymphoid organs. Additionally, we discuss how sympathetic mediators released by these neuron terminals affect immune cell function. Finally, we discuss emerging innovative technologies and potential clinical interventions targeting the ANS as a strategy to restore the normal regulation of the immune response in individuals with SCI.
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Affiliation(s)
- Maria M Moura
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057 Braga, Portugal; ICVS/3B's Associate Lab, PT Government Associated Lab, 4710-057 Braga, Guimarães, Portugal
| | - Andreia Monteiro
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057 Braga, Portugal; ICVS/3B's Associate Lab, PT Government Associated Lab, 4710-057 Braga, Guimarães, Portugal
| | - António J Salgado
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057 Braga, Portugal; ICVS/3B's Associate Lab, PT Government Associated Lab, 4710-057 Braga, Guimarães, Portugal
| | - Nuno A Silva
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057 Braga, Portugal; ICVS/3B's Associate Lab, PT Government Associated Lab, 4710-057 Braga, Guimarães, Portugal
| | - Susana Monteiro
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057 Braga, Portugal; ICVS/3B's Associate Lab, PT Government Associated Lab, 4710-057 Braga, Guimarães, Portugal.
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3
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Xu R, Treeby BE, Martin E. Safety Review of Therapeutic Ultrasound for Spinal Cord Neuromodulation and Blood-Spinal Cord Barrier Opening. ULTRASOUND IN MEDICINE & BIOLOGY 2024; 50:317-331. [PMID: 38182491 DOI: 10.1016/j.ultrasmedbio.2023.11.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2023] [Revised: 11/07/2023] [Accepted: 11/10/2023] [Indexed: 01/07/2024]
Abstract
New focused ultrasound spinal cord applications have emerged, particularly those improving therapeutic agent delivery to the spinal cord via blood-spinal cord barrier opening and the neuromodulation of spinal cord tracts. One hurdle in the development of these applications is safety. It may be possible to use safety trends from seminal and subsequent works in focused ultrasound to guide the development of safety guidelines for spinal cord applications. We collated data from decades of pre-clinical studies and illustrate a clear relationship between damage, time-averaged spatial peak intensity and exposure duration. This relationship suggests a thermal mechanism underlies ultrasound-induced spinal cord damage. We developed minimum and mean thresholds for damage from these pre-clinical studies. When these thresholds were plotted against the parameters used in recent pre-clinical ultrasonic spinal cord neuromodulation studies, the majority of the neuromodulation studies were near or above the minimum threshold. This suggests that a thermal neuromodulatory effect may exist for ultrasonic spinal cord neuromodulation, and that the thermal dose must be carefully controlled to avoid damage to the spinal cord. By contrast, the intensity-exposure duration threshold had no predictive value when applied to blood-spinal cord barrier opening studies that employed injected contrast agents. Most blood-spinal cord barrier opening studies observed slight to severe damage, except for small animal studies that employed an active feedback control method to limit pressures based on measured bubble oscillation behavior. The development of new focused ultrasound spinal cord applications perhaps reflects the recent success in the development of focused ultrasound brain applications, and recent work has begun on the translation of these technologies from brain to spinal cord. However, a great deal of work remains to be done, particularly with respect to developing and accepting safety standards for these applications.
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Affiliation(s)
- Rui Xu
- Department of Medical Physics and Biomedical Engineering, University College London, London, UK.
| | - Bradley E Treeby
- Department of Medical Physics and Biomedical Engineering, University College London, London, UK
| | - Eleanor Martin
- Department of Medical Physics and Biomedical Engineering, University College London, London, UK
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4
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Li Z, Zhai S, Liu S, Chen C, Guo X, Hu P, Wang B, Zhang Y, Wei F, Liu Z. A sheep model of chronic cervical compressive myelopathy via an implantable wireless compression device. EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 2022; 31:1219-1227. [PMID: 35192070 DOI: 10.1007/s00586-022-07138-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 01/04/2022] [Accepted: 01/27/2022] [Indexed: 10/19/2022]
Abstract
PURPOSE This study aimed to establish an animal model in which we can precisely displace the spinal cord and therefore mimic the chronic spinal compression of cervical spondylotic myelopathy. METHODS In vivo intervertebral compression devices (IVCDs) connected with subcutaneous control modules (SCCMs) were implanted into the C2-3 intervertebral disk spaces of sheep and connected by Bluetooth to an in vitro control system. Sixteen sheep were divided into four groups: (Group A) control; (Group B) 10-week progressive compression, then held; (Group C) 20-week progressive compression, then held; and (Group D) 20-week progressive compression, then decompression. Electrophysiological analysis (latency and amplitude of the N1-P1-N2 wave in somatosensory evoked potentials, SEP), behavioral changes (Tarlov score), imaging test (encroachment ratio (ER) of intraspinal invasion determined by X-ray and CT scan), and histological examinations (hematoxylin and eosin, Nissl, and TUNEL staining) were performed to assess the efficacy of our model. RESULTS Tarlov scores gradually decreased as compression increased with time and partially recovered after decompression. The Pearson correlation coefficient between ER and time was r = 0.993 (p < 0.001) in Group B at 10 weeks and Groups C and D at 20 weeks. And ER was negatively correlated with the Tarlov score (r = -0.878, p < 0.001). As compression progressed, the SEP latency was significantly extended (p < 0.001), and the amplitude significantly decreased (p < 0.001), while they were both partially restored after decompression. The number of abnormal motor neurons and TUNEL-positive cells increased significantly (p < 0.001) with compression. CONCLUSION Our implantable and wireless intervertebral compression model demonstrated outstanding controllability and reproducibility in simulating chronic cervical spinal cord compression in animals.
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Affiliation(s)
- Zihe Li
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing, 100191, China.,Engineering Research Center of Bone and Joint Precision Medicine, Ministry of Education, Beijing, China.,Beijing Key Laboratory of Spinal Disease Research, Beijing, China
| | - Shuheng Zhai
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing, 100191, China.,Engineering Research Center of Bone and Joint Precision Medicine, Ministry of Education, Beijing, China.,Beijing Key Laboratory of Spinal Disease Research, Beijing, China
| | - Shanshan Liu
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing, 100191, China.,Engineering Research Center of Bone and Joint Precision Medicine, Ministry of Education, Beijing, China.,Beijing Key Laboratory of Spinal Disease Research, Beijing, China
| | - Chunhua Chen
- Department of Anatomy and Embryology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Xinhu Guo
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing, 100191, China.,Engineering Research Center of Bone and Joint Precision Medicine, Ministry of Education, Beijing, China.,Beijing Key Laboratory of Spinal Disease Research, Beijing, China
| | - Panpan Hu
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing, 100191, China.,Engineering Research Center of Bone and Joint Precision Medicine, Ministry of Education, Beijing, China.,Beijing Key Laboratory of Spinal Disease Research, Beijing, China
| | - Ben Wang
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing, 100191, China.,Engineering Research Center of Bone and Joint Precision Medicine, Ministry of Education, Beijing, China.,Beijing Key Laboratory of Spinal Disease Research, Beijing, China
| | - Youyu Zhang
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing, 100191, China.,Engineering Research Center of Bone and Joint Precision Medicine, Ministry of Education, Beijing, China.,Beijing Key Laboratory of Spinal Disease Research, Beijing, China
| | - Feng Wei
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing, 100191, China. .,Engineering Research Center of Bone and Joint Precision Medicine, Ministry of Education, Beijing, China. .,Beijing Key Laboratory of Spinal Disease Research, Beijing, China.
| | - Zhongjun Liu
- Department of Orthopaedics, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing, 100191, China.,Engineering Research Center of Bone and Joint Precision Medicine, Ministry of Education, Beijing, China.,Beijing Key Laboratory of Spinal Disease Research, Beijing, China
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Bismuth M, Katz S, Rosenblatt H, Twito M, Aronovich R, Ilovitsh T. Acoustically Detonated Microbubbles Coupled with Low Frequency Insonation: Multiparameter Evaluation of Low Energy Mechanical Ablation. Bioconjug Chem 2021; 33:1069-1079. [PMID: 34280311 PMCID: PMC9204695 DOI: 10.1021/acs.bioconjchem.1c00203] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
![]()
Noninvasive
ultrasound surgery can be achieved using focused ultrasound
to locally affect the targeted site without damaging intervening tissues.
Mechanical ablation and histotripsy use short and intense acoustic
pulses to destroy the tissue via a purely mechanical effect. Here,
we show that coupled with low-frequency excitation, targeted microbubbles
can serve as mechanical therapeutic warheads that trigger potent mechanical
effects in tumors using focused ultrasound. Upon low frequency excitation
(250 kHz and below), high amplitude microbubble oscillations occur
at substantially lower pressures as compared to higher MHz ultrasonic
frequencies. For example, inertial cavitation was initiated at a pressure
of 75 kPa for a center frequency of 80 kHz. Low frequency insonation
of targeted microbubbles was then used to achieve low energy tumor
cell fractionation at pressures below a mechanical index of 1.9, and
in accordance with the Food and Drug Administration guidelines. We
demonstrate these capabilities in vitro and in vivo. In cell cultures,
cell viability was reduced to 16% at a peak negative pressure of 800
kPa at the 250 kHz frequency (mechanical index of 1.6) and to 10%
at a peak negative pressure of 250 kPa at a frequency of 80 kHz (mechanical
index of 0.9). Following an intratumoral injection of targeted microbubbles
into tumor-bearing mice, and coupled with low frequency ultrasound
application, significant tumor debulking and cancer cell death was
observed. Our findings suggest that reducing the center frequency
enhances microbubble-mediated mechanical ablation; thus, this technology
provides a unique theranostic platform for safe low energy tumor fractionation,
while reducing off-target effects.
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Affiliation(s)
- Mike Bismuth
- Department of Biomedical Engineering, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Sharon Katz
- Department of Biomedical Engineering, Tel Aviv University, Tel Aviv 6997801, Israel.,The Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Hagar Rosenblatt
- Department of Biomedical Engineering, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Maayan Twito
- Department of Biomedical Engineering, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Ramona Aronovich
- Department of Biomedical Engineering, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Tali Ilovitsh
- Department of Biomedical Engineering, Tel Aviv University, Tel Aviv 6997801, Israel.,The Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 6997801, Israel
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6
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Hwang BY, Mampre D, Ahmed AK, Suk I, Anderson WS, Manbachi A, Theodore N. Ultrasound in Traumatic Spinal Cord Injury: A Wide-Open Field. Neurosurgery 2021; 89:372-382. [PMID: 34098572 DOI: 10.1093/neuros/nyab177] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Accepted: 03/19/2021] [Indexed: 02/02/2023] Open
Abstract
Traumatic spinal cord injury (SCI) is a common and devastating condition. In the absence of effective validated therapies, there is an urgent need for novel methods to achieve injury stabilization, regeneration, and functional restoration in SCI patients. Ultrasound is a versatile platform technology that can provide a foundation for viable diagnostic and therapeutic interventions in SCI. In particular, real-time perfusion and inflammatory biomarker monitoring, focal pharmaceutical delivery, and neuromodulation are capabilities that can be harnessed to advance our knowledge of SCI pathophysiology and to develop novel management and treatment options. Our review suggests that studies that evaluate the benefits and risks of ultrasound in SCI are severely lacking and our understanding of the technology's potential impact remains poorly understood. Although the complex anatomy and physiology of the spine and the spinal cord remain significant challenges, continued technological advances will help the field overcome the current barriers and bring ultrasound to the forefront of SCI research and development.
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Affiliation(s)
- Brian Y Hwang
- Division of Functional Neurosurgery, Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - David Mampre
- Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - A Karim Ahmed
- Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Ian Suk
- Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - William S Anderson
- Division of Functional Neurosurgery, Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Amir Manbachi
- Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Nicholas Theodore
- Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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7
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Kwiecien JM, Dąbrowski W, Yaron JR, Zhang L, Delaney KH, Lucas AR. The Role of Astrogliosis in Formation of the Syrinx in Spinal Cord Injury. Curr Neuropharmacol 2021; 19:294-303. [PMID: 32691715 PMCID: PMC8033977 DOI: 10.2174/1570159x18666200720225222] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 06/09/2020] [Accepted: 07/16/2020] [Indexed: 12/28/2022] Open
Abstract
A massive localized trauma to the spinal cord results in complex pathologic events driven by necrosis and vascular damage which in turn leads to hemorrhage and edema. Severe, destructive and very protracted inflammatory response is characterized by infiltration by phagocytic macrophages of a site of injury which is converted into a cavity of injury (COI) surrounded by astroglial reaction mounted by the spinal cord. The tissue response to the spinal cord injury (SCI) has been poorly understood but the final outcome appears to be a mature syrinx filled with the cerebrospinal fluid with related neural tissue loss and permanent neurologic deficits. This paper reviews known pathologic mechanisms involved in the formation of the COI after SCI and discusses the integrative role of reactive astrogliosis in mechanisms involved in the removal of edema after the injury. A large proportion of edema fluid originating from the trauma and then from vasogenic edema related to persistent severe inflammation, may be moved into the COI in an active process involving astrogliosis and specifically over-expressed aquaporins.
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Affiliation(s)
- Jacek M. Kwiecien
- Department of Pathology and Molecular Medicine, Faculty of Health Sciences, McMaster University, Hamilton, ON, Canada
| | - Wojciech Dąbrowski
- Department of Anaesthesiology and Intensive Therapy, Medical University of Lublin, ul. Jaczewskiego 8, Lublin 20-090 Poland
| | - Jordan R Yaron
- Center for Personalized Diagnostics and Center for Immunotherapy, Vaccines and Virotherapy, Biodesign Institute, Arizona State University, Tempe, AZ, U.S.A
| | - Liqiang Zhang
- Center for Personalized Diagnostics and Center for Immunotherapy, Vaccines and Virotherapy, Biodesign Institute, Arizona State University, Tempe, AZ, U.S.A
| | - Kathleen H. Delaney
- Department of Pathology and Molecular Medicine, Faculty of Health Sciences, McMaster University, Hamilton, ON, Canada
| | - Alexandra R. Lucas
- Center for Personalized Diagnostics and Center for Immunotherapy, Vaccines and Virotherapy, Biodesign Institute, Arizona State University, Tempe, AZ, U.S.A
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8
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Kwiecien JM. The Pathogenesis of Neurotrauma Indicates Targets for Neuroprotective Therapies. Curr Neuropharmacol 2021; 19:1191-1201. [PMID: 33550977 PMCID: PMC8719295 DOI: 10.2174/1570159x19666210125153308] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 11/06/2020] [Accepted: 01/24/2021] [Indexed: 11/22/2022] Open
Abstract
The spinal cord injury (SCI) initiates an extraordinarily protracted disease with 3 phases; acute, inflammatory, and resolution that are restricted to the cavity of injury (COI) or arachnoiditis by a unique CNS reaction against the severity of destructive inflammation. While the severity of inflammation involving the white matter is fueled by a potently immunogenic activity of damaged myelin, its sequestration in the COI and its continuity with the cerebrospinal fluid of the subdural space allow anti-inflammatory therapeutics infused subdurally to inhibit phagocytic macrophage infiltration and thus provide neuroprotection. The role of astrogliosis in containing and ultimately in eliminating severe destructive inflammation post-trauma appears obvious but is not yet sufficiently understood to use in therapeutic neuroprotective and neuroregenerative strategies. An apparent antiinflammatory activity of reactive astrocytes is paralleled by their active role in removing excess edema fluid in blood-brain barrier damaged by inflammation. Recently elucidated pathogenesis of neurotrauma, including SCI, traumatic brain injury (TBI), and stroke, calls for the following principal therapeutic steps in its treatment leading to the recovery of neurologic function: (1) inhibition and elimination of destructive inflammation from the COI with accompanying reduction of vasogenic edema, (2) insertion into the COI of a functional bridge supporting the crossing of regenerating axons, (3) enabling regeneration of axons to their original synaptic targets by temporary safe removal of myelin in targeted areas of white matter, (4) in vivo, systematic monitoring of the consecutive therapeutic steps. The focus of this paper is on therapeutic step 1.
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Affiliation(s)
- Jacek M. Kwiecien
- Department of Pathology and Molecular Medicine, Faculty of Health Sciences, McMaster University, Room HSC 1U22D, 1280 Main Street West, Hamilton, ON, L4S 4K1, Canada
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9
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Kwiecien JM, Dabrowski W, Dąbrowska-Bouta B, Sulkowski G, Oakden W, Kwiecien-Delaney CJ, Yaron JR, Zhang L, Schutz L, Marzec-Kotarska B, Stanisz GJ, Karis JP, Struzynska L, Lucas AR. Prolonged inflammation leads to ongoing damage after spinal cord injury. PLoS One 2020; 15:e0226584. [PMID: 32191733 PMCID: PMC7081990 DOI: 10.1371/journal.pone.0226584] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Accepted: 02/28/2020] [Indexed: 12/27/2022] Open
Abstract
The pathogenesis of spinal cord injury (SCI) remains poorly understood and treatment remains limited. Emerging evidence indicates that post-SCI inflammation is severe but the role of reactive astrogliosis not well understood given its implication in ongoing inflammation as damaging or neuroprotective. We have completed an extensive systematic study with MRI, histopathology, proteomics and ELISA analyses designed to further define the severe protracted and damaging inflammation after SCI in a rat model. We have identified 3 distinct phases of SCI: acute (first 2 days), inflammatory (starting day 3) and resolution (>3 months) in 16 weeks follow up. Actively phagocytizing, CD68+/CD163- macrophages infiltrate myelin-rich necrotic areas converting them into cavities of injury (COI) when deep in the spinal cord. Alternatively, superficial SCI areas are infiltrated by granulomatous tissue, or arachnoiditis where glial cells are obliterated. In the COI, CD68+/CD163- macrophage numbers reach a maximum in the first 4 weeks and then decline. Myelin phagocytosis is present at 16 weeks indicating ongoing inflammatory damage. The COI and arachnoiditis are defined by a wall of progressively hypertrophied astrocytes. MR imaging indicates persistent spinal cord edema that is linked to the severity of inflammation. Microhemorrhages in the spinal cord around the lesion are eliminated, presumably by reactive astrocytes within the first week post-injury. Acutely increased levels of TNF-alpha, IL-1beta, IFN-gamma and other pro-inflammatory cytokines, chemokines and proteases decrease and anti-inflammatory cytokines increase in later phases. In this study we elucidated a number of fundamental mechanisms in pathogenesis of SCI and have demonstrated a close association between progressive astrogliosis and reduction in the severity of inflammation.
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Affiliation(s)
- Jacek M. Kwiecien
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
- * E-mail:
| | - Wojciech Dabrowski
- Department of Anaesthesiology and Intensive Therapy, Medical University of Lublin, Lublin, Poland
| | - Beata Dąbrowska-Bouta
- Laboratory of Pathoneurochemistry, Mossakowski Medical Research Center, Polish Academy of Sciences, Warsaw, Poland
| | - Grzegorz Sulkowski
- Laboratory of Pathoneurochemistry, Mossakowski Medical Research Center, Polish Academy of Sciences, Warsaw, Poland
| | - Wendy Oakden
- Physical Sciences, Sunnybrook Research Institute, Toronto, Ontario, Canada
| | | | - Jordan R. Yaron
- Centers for Personalized Diagnostics and Immunotherapy, Vaccines and Virotherapy, Biodesign Institute, Arizona State University, Tempe, Arizona, United States of America
| | - Liqiang Zhang
- Centers for Personalized Diagnostics and Immunotherapy, Vaccines and Virotherapy, Biodesign Institute, Arizona State University, Tempe, Arizona, United States of America
| | - Lauren Schutz
- Centers for Personalized Diagnostics and Immunotherapy, Vaccines and Virotherapy, Biodesign Institute, Arizona State University, Tempe, Arizona, United States of America
| | | | - Greg J. Stanisz
- Physical Sciences, Sunnybrook Research Institute, Toronto, Ontario, Canada
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
| | - John P. Karis
- Department of Neuroradiology, Barrow Neurological Institute, Dignity Health St. Joseph’s Hospital and Medical Center, Phoenix, Arizona, United States of America
| | - Lidia Struzynska
- Laboratory of Pathoneurochemistry, Mossakowski Medical Research Center, Polish Academy of Sciences, Warsaw, Poland
| | - Alexandra R. Lucas
- Centers for Personalized Diagnostics and Immunotherapy, Vaccines and Virotherapy, Biodesign Institute, Arizona State University, Tempe, Arizona, United States of America
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10
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Abstract
As the systematic work on the pathogenesis of the white matter injury in the spinal cord models progresses, it becomes obvious that a severe and extraordinarily protracted, destructive inflammation follows the initial injury. Appropriate anti-inflammatory therapies of sufficient duration should not only inhibit but also lead to the elimination of this destructive inflammation, thus resulting in neuroprotection of the spinal cord tissue and a greater preservation of the neurologic function. While dexamethasone, a powerful, anti-inflammatory steroid analog administered continuously by subdural infusion for 7 days inhibited severe macrophage infiltration in the cavity of injury, the dose used was remarkably toxic. A 2-week-long infusion of lower doses of dexamethasone resulted in dose-dependent inhibition of macrophage infiltration and was better tolerated by the rats, but it became evident that a much longer duration of subdural administration of a powerful anti-inflammatory drug is required to eliminate myelin-rich, necrotic debris from the cavity and synthetic steroids such as dexamethasone, and methylprednisolone may be too toxic for this application. Therefore, nontoxic but powerful anti-inflammatory compounds are required for neuroprotective treatment of the spinal cord injury (SCI) and also brain trauma and stroke where the massive injury to the white matter occurs. Serpins have been associated with neurological damage. The mammalian serpin neuroserpin (SERPINI1) is reported to act in a protective manner after cerebrospinal infarction. The serine protease, tissue-type plasminogen activator (tPA), and the serpin plasminogen activator inhibitor (PAI-1, SERPINE1) are both upregulated at sites of central nervous system damage. In preliminary studies, subdural infusion of the myxomaviral serpin, Serp-1, resulted in the powerful inhibition of the macrophage infiltration of the cavity of injury, comparable to the inhibition by high dose of dexamethasone that has proven to be unduly toxic. Nontoxic, yet powerful neuroprotective, anti-inflammatory effects of Serp-1 may indicate this serpin protein as a potential attractive compound to treat SCI and similar syndromes involving massive injury to the white matter such as brain trauma and stroke. Novel methods of drug delivery, chronic subdural infusion, and novel analytic methods to measure the effectiveness of the neuroprotective serpin treatments are discussed in this chapter.
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Affiliation(s)
- Jacek M Kwiecien
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, ON, Canada.
- Department of Clinical Pathomorphology, Medical University of Lublin, Lublin, Poland.
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11
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Payne AH, Hawryluk GW, Anzai Y, Odéen H, Ostlie MA, Reichert EC, Stump AJ, Minoshima S, Cross DJ. Magnetic resonance imaging-guided focused ultrasound to increase localized blood-spinal cord barrier permeability. Neural Regen Res 2017; 12:2045-2049. [PMID: 29323044 PMCID: PMC5784353 DOI: 10.4103/1673-5374.221162] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Spinal cord injury (SCI) affects thousands of people every year in the USA, and most patients are left with some permanent paralysis. Therapeutic options are limited and only modestly affect outcome. To address this issue, we used magnetic resonance imaging-guided focused ultrasound (MRgFUS) as a non-invasive approach to increase permeability in the blood-spinal cord barrier (BSCB). We hypothesize that localized, controlled sonoporation of the BSCB by MRgFUS will aid delivery of therapeutics to the injury. Here, we report our preliminary findings for the ability of MRgFUS to increase BSCB permeability in the thoracic spinal cord of a normal rat model. First, an excised portion of normal rat spinal column was used to characterize the acoustic field and to estimate the insertion losses that could be expected in an MRgFUS blood spinal cord barrier opening. Then, in normal rats, MRgFUS was applied in combination with intravenously administered microbubbles to the spinal cord region. Permeability of the BSCB was indicated as signal enhancement by contrast administered prior to T1-weighted magnetic resonance imaging and verified by Evans blue dye. Neurological testing using the Basso, Beattie, and Breshnahan scale and the ladder walk was normal in 8 of 10 rats tested. Two rats showed minor impairment indicating need for further refinement of parameters. No gross tissue damage was evident by histology. In this study, we have opened successfully the blood spinal cord barrier in the thoracic region of the normal rat spine using magnetic resonance-guided focused ultrasound combined with microbubbles.
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Affiliation(s)
- Allison H Payne
- Department of Radiology and Imaging Sciences, University of Utah, Salt Lake City, UT, USA
| | | | - Yoshimi Anzai
- Department of Radiology and Imaging Sciences, University of Utah, Salt Lake City, UT, USA
| | - Henrik Odéen
- Department of Radiology and Imaging Sciences, University of Utah, Salt Lake City, UT, USA
| | - Megan A Ostlie
- Department of Radiology and Imaging Sciences, University of Utah, Salt Lake City, UT, USA
| | - Ethan C Reichert
- Department of Neurosurgery, University of Utah, Salt Lake City, UT, USA
| | - Amanda J Stump
- Department of Radiology and Imaging Sciences, University of Utah, Salt Lake City, UT, USA
| | - Satoshi Minoshima
- Department of Radiology and Imaging Sciences, University of Utah, Salt Lake City, UT, USA
| | - Donna J Cross
- Department of Radiology and Imaging Sciences, University of Utah, Salt Lake City, UT, USA
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Bing C, Nofiele J, Staruch R, Ladouceur-Wodzak M, Chatzinoff Y, Ranjan A, Chopra R. Localised hyperthermia in rodent models using an MRI-compatible high-intensity focused ultrasound system. Int J Hyperthermia 2015; 31:813-22. [PMID: 26540488 DOI: 10.3109/02656736.2015.1094833] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
PURPOSE Localised hyperthermia in rodent studies is challenging due to the small target size. This study describes the development and characterisation of an MRI-compatible high-intensity focused ultrasound (HIFU) system to perform localised mild hyperthermia treatments in rodent models. MATERIAL AND METHODS The hyperthermia platform consisted of an MRI-compatible small animal HIFU system, focused transducers with sector-vortex lenses, a custom-made receive coil, and means to maintain systemic temperatures of rodents. The system was integrated into a 3T MR imager. Control software was developed to acquire images, process temperature maps, and adjust output power using a proportional-integral-derivative feedback control algorithm. Hyperthermia exposures were performed in tissue-mimicking phantoms and in a rodent model (n = 9). During heating, an ROI was assigned in the heated region for temperature control and the target temperature was 42 °C; 30 min mild hyperthermia treatment followed by a 10-min cooling procedure was performed on each animal. RESULTS 3D-printed sector-vortex lenses were successful at creating annular focal regions which enables customisation of the heating volume. Localised mild hyperthermia performed in rats produced a mean ROI temperature of 42.1 ± 0.3 °C. The T10 and T90 percentiles were 43.2 ± 0.4 °C and 41.0 ± 0.3 °C, respectively. For a 30-min treatment, the mean time duration between 41-45 °C was 31.1 min within the ROI. CONCLUSIONS The MRI-compatible HIFU system was successfully adapted to perform localised mild hyperthermia treatment in rodent models. A target temperature of 42 °C was well-maintained in a rat thigh model for 30 min.
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Affiliation(s)
- Chenchen Bing
- a Department of Radiology , University of Texas Southwestern Medical Center , Dallas , Texas
| | - Joris Nofiele
- a Department of Radiology , University of Texas Southwestern Medical Center , Dallas , Texas
| | - Robert Staruch
- a Department of Radiology , University of Texas Southwestern Medical Center , Dallas , Texas .,b Clinical Sites Research Program, Philips Research , Briarcliff Manor , New York
| | | | - Yonatan Chatzinoff
- c Applied Research Center, University of Texas at Dallas , Dallas , Texas
| | - Ashish Ranjan
- d Center of Veterinary Health Sciences, Oklahoma State University , Stillwater , Oklahoma , USA , and
| | - Rajiv Chopra
- a Department of Radiology , University of Texas Southwestern Medical Center , Dallas , Texas .,e Advanced Imaging Research Center, University of Texas Southwestern Medical Center , Dallas , Texas
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13
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Oakden W, Kwiecien JM, O'Reilly MA, Dabrowski W, Whyne C, Finkelstein J, Hynynen K, Stanisz GJ. Quantitative MRI in a non-surgical model of cervical spinal cord injury. NMR IN BIOMEDICINE 2015; 28:925-936. [PMID: 26053102 DOI: 10.1002/nbm.3326] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Revised: 04/16/2015] [Accepted: 04/19/2015] [Indexed: 06/04/2023]
Abstract
Quantitative T2 (qT2), diffusion tensor imaging (DTI), and histology were used to investigate a cervical model of spinal cord injury (SCI) in the rat. While quantitative MRI can significantly increase the specificity in the presence of pathology, it must be validated for each type of injury or disease. In the case of traumatic SCI most models are difficult to image, either due to the location of the injury, or as a result of damage to surrounding tissues resulting from invasive surgical procedures. In this study a non-surgical cervical model of SCI, produced using a combination of focused ultrasound and microbubbles, was used to produce pathology similar to that seen in models of contusive and compressive injuries. qT2 and DTI were performed at 24 h and 1 and 2 weeks following injury, and compared with H&E and luxol fast blue histology. In the injured spinal cord, in addition to intra/extracellular (I/E) water and myelin water in white matter, qT2 revealed a large component with very short T2 of about 3 ms, which was highly correlated with the presence of hemorrhage in both gray and white matter at 24 h, and with the presence of hemosiderin in gray matter at 2 weeks following injury. The T2 of the I/E water peak was also elevated at 24 h in both gray and white matter, which was correlated with the presence of vacuolation/edema on histology. Cystic cavities were only seen at the 1 or 2 week timepoints, and were correlated with the presence of a water peak with T2 > 250 ms. No significant changes in diffusivity parameters were observed. Pathologies were often co-occurring, with opposite effects on the average T2 in a given voxel, reducing the visibility of injured tissue on standard T2 -weighted MR images.
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Affiliation(s)
- Wendy Oakden
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
| | - Jacek M Kwiecien
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Meaghan A O'Reilly
- Sciences Platform, Sunnybrook Research Institute, Toronto, Ontario, Canada
| | - Wojciech Dabrowski
- Department of Anaesthesiology and Intensive Therapy, Medical University of Lublin, Lublin, Poland
| | - Cari Whyne
- Orthopaedic Biomechanics Laboratory, Sunnybrook Research Institute, Toronto, Ontario, Canada
- Division of Orthopaedics, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
| | - Joel Finkelstein
- Division of Orthopaedics, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
- Department of Surgery, University of Toronto, Toronto, Ontario, Canada
| | - Kullervo Hynynen
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
- Sciences Platform, Sunnybrook Research Institute, Toronto, Ontario, Canada
| | - Greg J Stanisz
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
- Sciences Platform, Sunnybrook Research Institute, Toronto, Ontario, Canada
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Gene delivery to the spinal cord using MRI-guided focused ultrasound. Gene Ther 2015; 22:568-77. [PMID: 25781651 PMCID: PMC4490035 DOI: 10.1038/gt.2015.25] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Revised: 02/26/2015] [Accepted: 03/05/2015] [Indexed: 12/18/2022]
Abstract
Non-invasive gene delivery across the blood-spinal cord barrier (BSCB) remains a challenge for treatment of spinal cord injury and disease. Here, we demonstrate the use of magnetic resonance image-guided focused ultrasound (MRIgFUS) to mediate non-surgical gene delivery to the spinal cord using self-complementary adeno-associated virus serotype 9 (scAAV9). scAAV9 encoding green fluorescent protein (GFP) was injected intravenously in rats at three dosages: 4 × 10(8), 2 × 10(9) and 7 × 10(9) vector genomes per gram (VG g(-1)). MRIgFUS allowed for transient, targeted permeabilization of the BSCB through the interaction of focused ultrasound (FUS) with systemically injected Definity lipid-shelled microbubbles. Viral delivery at 2 × 10(9) and 7 × 10(9) VG g(-1) leads to robust GFP expression in FUS-targeted regions of the spinal cord. At a dose of 2 × 10(9) VG g(-1), GFP expression was found in 36% of oligodendrocytes, and in 87% of neurons in FUS-treated areas. FUS applications to the spinal cord could address a long-term goal of gene therapy: delivering vectors from the circulation to diseased areas in a non-invasive manner.
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