1
|
Victorio CBL, Ganasarajah A, Novera W, Ong J, Msallam R, Chacko AM. Translocator protein (TSPO) is a biomarker of Zika virus (ZIKV) infection-associated neuroinflammation. Emerg Microbes Infect 2024; 13:2348528. [PMID: 38662785 PMCID: PMC11132733 DOI: 10.1080/22221751.2024.2348528] [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: 01/31/2024] [Accepted: 04/23/2024] [Indexed: 05/29/2024]
Abstract
Zika is a systemic inflammatory disease caused by infection with Zika virus (ZIKV). ZIKV infection in adults is associated with encephalitis marked by elevated expression of pro-inflammatory cytokines and chemokines, as well as increased brain infiltration of immune cells. In this study, we demonstrate that ZIKV encephalitis in a mouse infection model exhibits increased brain TSPO expression. TSPO expression on brain-resident and infiltrating immune cells in ZIKV infection correlates with disease and inflammation status in the brain. Brain TSPO expression can also be sensitively detected ex vivo and in vitro using radioactive small molecule probes that specifically bind to TSPO, such as [3H]PK11195. TSPO expression on brain-resident and infiltrating immune cells is a biomarker of ZIKV neuroinflammation, which can also be a general biomarker of acute viral neuroinflammatory disease.
Collapse
Affiliation(s)
- Carla Bianca Luena Victorio
- Laboratory for Translational and Molecular Imaging (LTMI), Cancer and Stem Cell Biology Programme, Duke-NUS Medical School, Singapore, Singapore
| | - Arun Ganasarajah
- Laboratory for Translational and Molecular Imaging (LTMI), Cancer and Stem Cell Biology Programme, Duke-NUS Medical School, Singapore, Singapore
| | - Wisna Novera
- Laboratory for Translational and Molecular Imaging (LTMI), Cancer and Stem Cell Biology Programme, Duke-NUS Medical School, Singapore, Singapore
| | - Joanne Ong
- Laboratory for Translational and Molecular Imaging (LTMI), Cancer and Stem Cell Biology Programme, Duke-NUS Medical School, Singapore, Singapore
| | - Rasha Msallam
- Laboratory for Translational and Molecular Imaging (LTMI), Cancer and Stem Cell Biology Programme, Duke-NUS Medical School, Singapore, Singapore
| | - Ann-Marie Chacko
- Laboratory for Translational and Molecular Imaging (LTMI), Cancer and Stem Cell Biology Programme, Duke-NUS Medical School, Singapore, Singapore
| |
Collapse
|
2
|
Knyzeliene A, MacAskill MG, Alcaide-Corral CJ, Morgan TEF, Henry MC, Lucatelli C, Pimlott SL, Sutherland A, Tavares AAS. [ 18F]LW223 has low non-displaceable binding in murine brain, enabling high sensitivity TSPO PET imaging. J Cereb Blood Flow Metab 2024; 44:397-406. [PMID: 37795635 PMCID: PMC10870961 DOI: 10.1177/0271678x231205661] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 09/01/2023] [Accepted: 09/09/2023] [Indexed: 10/06/2023]
Abstract
Neuroinflammation is associated with a number of brain diseases, making it a common feature of cerebral pathology. Among the best-known biomarkers for neuroinflammation in Positron Emission Tomography (PET) research is the 18 kDa translocator protein (TSPO). This study aims to investigate the binding kinetics of a novel TSPO PET radiotracer, [18F]LW223, in mice and specifically assess its volume of non-displaceable binding (VND) in brain as well as investigate the use of simplified analysis approaches for quantification of [18F]LW223 PET data. Adult male mice were injected with [18F]LW223 and varying concentrations of LW223 (0.003-0.55 mg/kg) to estimate VND of [18F]LW223. Dynamic PET imaging with arterial input function studies and radiometabolite studies were conducted. Simplified quantification methods, standard uptake values (SUV) and apparent volume of distribution (VTapp), were investigated. [18F]LW223 had low VND in the brain (<10% of total binding) and low radiometabolism (∼15-20%). The 2-tissue compartment model provided the best fit for [18F]LW223 PET data, although its correlation with SUV90-120min or VTapp allowed for [18F]LW223 brain PET data quantification in healthy animals while using simpler experimental and analytical approaches. [18F]LW223 has the required properties to become a successful TSPO PET radiotracer.
Collapse
Affiliation(s)
- Agne Knyzeliene
- BHF-University of Edinburgh Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
- Edinburgh Imaging, University of Edinburgh, Edinburgh, UK
| | - Mark G MacAskill
- BHF-University of Edinburgh Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
- Edinburgh Imaging, University of Edinburgh, Edinburgh, UK
| | - Carlos J Alcaide-Corral
- BHF-University of Edinburgh Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
- Edinburgh Imaging, University of Edinburgh, Edinburgh, UK
| | - Timaeus EF Morgan
- BHF-University of Edinburgh Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
- Edinburgh Imaging, University of Edinburgh, Edinburgh, UK
| | | | | | - Sally L Pimlott
- West of Scotland PET Centre, Greater Glasgow and Clyde NHS Trust, Glasgow, UK
| | | | - Adriana AS Tavares
- BHF-University of Edinburgh Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
- Edinburgh Imaging, University of Edinburgh, Edinburgh, UK
| |
Collapse
|
3
|
Conti E, Grana D, Angiulli F, Karantzoulis A, Villa C, Combi R, Appollonio I, Ferrarese C, Tremolizzo L. TSPO Modulates Oligomeric Amyloid-β-Induced Monocyte Chemotaxis: Relevance for Neuroinflammation in Alzheimer's Disease. J Alzheimers Dis 2023; 95:549-559. [PMID: 37574731 DOI: 10.3233/jad-230239] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
BACKGROUND Neuroinflammation is one of the cardinal mechanisms of Alzheimer's disease (AD). with amyloid-β (Aβ) playing a critical role by activating microglia to produce soluble inflammatory mediators, including several chemokines. Peripheral monocytes are, therefore, attracted into the central nervous system (CNS), where they change into blood-born microglia and participate in the attempt of removing toxic Aβ species. The translocator protein-18 kDa (TSPO) is a transmembrane protein overexpressed in response to neuroinflammation and known to regulate human monocyte chemotaxis. OBJECTIVE We aimed to evaluate the role of the oligomeric Aβ1-42 isoform at inducing peripheral monocyte chemotaxis, and the possible involvement of TSPO in this process. METHODS In vitro cell lines, and ex vivo monocytes from consecutive AD patients (n = 60), and comparable cognitively intact controls (n = 30) were used. Chemotaxis analyses were carried out through both μ-slide chambers and Boyden assays, using 125 pM oligomeric Aβ1-42 as chemoattractant. TSPO agonists and antagonists were tested (Ro5-4864, Emapunil, PK11195). RESULTS Oligomeric Aβ directly promoted chemotaxis in all our models. Interestingly, AD monocytes displayed a stronger response (about twofold) with respect to controls. Aβ-induced chemotaxis was prevented by the TSPO antagonist PK11195; the expression of the TSPO and of the C-C chemokine receptor type 2 (CCR2) was unchanged by drug exposure. CONCLUSION Oligomeric Aβ1-42 is able to recruit peripheral monocytes, and we provide initial evidence sustaining a role for TSPO in modulating this process. This data may be of value for future therapeutic interventions aimed at modulating monocytes motility toward the CNS.
Collapse
Affiliation(s)
- Elisa Conti
- School of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy
- Milan Center for Neuroscience (NeuroMi), Italy
| | - Denise Grana
- School of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy
- Milan Center for Neuroscience (NeuroMi), Italy
| | - Federica Angiulli
- School of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy
- Milan Center for Neuroscience (NeuroMi), Italy
| | - Aristotelis Karantzoulis
- Milan Center for Neuroscience (NeuroMi), Italy
- Memory Clinic, Neurology Unit, IRCCS "San Gerardo dei Tintori", Monza, Italy
| | - Chiara Villa
- School of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy
- Milan Center for Neuroscience (NeuroMi), Italy
| | - Romina Combi
- School of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy
- Milan Center for Neuroscience (NeuroMi), Italy
| | - Ildebrando Appollonio
- School of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy
- Milan Center for Neuroscience (NeuroMi), Italy
- Memory Clinic, Neurology Unit, IRCCS "San Gerardo dei Tintori", Monza, Italy
| | - Carlo Ferrarese
- School of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy
- Milan Center for Neuroscience (NeuroMi), Italy
- Memory Clinic, Neurology Unit, IRCCS "San Gerardo dei Tintori", Monza, Italy
| | - Lucio Tremolizzo
- School of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy
- Milan Center for Neuroscience (NeuroMi), Italy
- Memory Clinic, Neurology Unit, IRCCS "San Gerardo dei Tintori", Monza, Italy
| |
Collapse
|
4
|
Martinez-Orengo N, Tahmazian S, Lai J, Wang Z, Sinharay S, Schreiber-Stainthorp W, Basuli F, Maric D, Reid W, Shah S, Hammoud DA. Assessing organ-level immunoreactivity in a rat model of sepsis using TSPO PET imaging. Front Immunol 2022; 13:1010263. [PMID: 36439175 PMCID: PMC9685400 DOI: 10.3389/fimmu.2022.1010263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Accepted: 10/17/2022] [Indexed: 11/11/2022] Open
Abstract
There is current need for new approaches to assess/measure organ-level immunoreactivity and ensuing dysfunction in systemic inflammatory response syndrome (SIRS) and sepsis, in order to protect or recover organ function. Using a rat model of systemic sterile inflammatory shock (intravenous LPS administration), we performed PET imaging with a translocator protein (TSPO) tracer, [18F]DPA-714, as a biomarker for reactive immunoreactive changes in the brain and peripheral organs. In vivo dynamic PET/CT scans showed increased [18F]DPA-714 binding in the brain, lungs, liver and bone marrow, 4 hours after LPS injection. Post-LPS mean standard uptake values (SUVmean) at equilibrium were significantly higher in those organs compared to baseline. Changes in spleen [18F]DPA-714 binding were variable but generally decreased after LPS. SUVmean values in all organs, except the spleen, positively correlated with several serum cytokines/chemokines. In vitro measures of TSPO expression and immunofluorescent staining validated the imaging results. Noninvasive molecular imaging with [18F]DPA-714 PET in a rat model of systemic sterile inflammatory shock, along with in vitro measures of TSPO expression, showed brain, liver and lung inflammation, spleen monocytic efflux/lymphocytic activation and suggested increased bone marrow hematopoiesis. TSPO PET imaging can potentially be used to quantify SIRS and sepsis-associated organ-level immunoreactivity and assess the effectiveness of therapeutic and preventative approaches for associated organ failures, in vivo.
Collapse
Affiliation(s)
- Neysha Martinez-Orengo
- Center for Infectious Disease Imaging, Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, MD, United States
| | - Sarine Tahmazian
- Center for Infectious Disease Imaging, Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, MD, United States
| | - Jianhao Lai
- Center for Infectious Disease Imaging, Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, MD, United States
| | - Zeping Wang
- Center for Infectious Disease Imaging, Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, MD, United States
| | - Sanhita Sinharay
- Center for Infectious Disease Imaging, Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, MD, United States
| | - William Schreiber-Stainthorp
- Center for Infectious Disease Imaging, Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, MD, United States
| | - Falguni Basuli
- Chemistry and Synthesis Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Rockville, MD, United States
| | - Dragan Maric
- Flow and Imaging Cytometry Core Facility, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, United States
| | - William Reid
- Center for Infectious Disease Imaging, Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, MD, United States
| | - Swati Shah
- Center for Infectious Disease Imaging, Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, MD, United States
| | - Dima A. Hammoud
- Center for Infectious Disease Imaging, Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, MD, United States
- *Correspondence: Dima A. Hammoud,
| |
Collapse
|
5
|
Corsi F, Baglini E, Barresi E, Salerno S, Cerri C, Martini C, Da Settimo Passetti F, Taliani S, Gargini C, Piano I. Targeting TSPO Reduces Inflammation and Apoptosis in an In Vitro Photoreceptor-Like Model of Retinal Degeneration. ACS Chem Neurosci 2022; 13:3188-3197. [PMID: 36300862 PMCID: PMC9673150 DOI: 10.1021/acschemneuro.2c00582] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
The 18 kDa translocator protein (TSPO) is predominantly located in the mitochondrial outer membrane, playing an important role in steroidogenesis, inflammation, survival, and cell proliferation. Its expression in the CNS, and mainly in glial cells, is upregulated in neuropathologies and brain injury. In this study, the potential of targeting TSPO for the therapeutic treatment of inflammatory-based retinal neurodegeneration was evaluated by means of an in vitro model of lipopolysaccharide (LPS)-induced degeneration in 661 W cells, a photoreceptor-like cell line. After the assessment of the expression of TSPO in 661W cells, which, to the best of our knowledge, was never investigated so far, the anti-inflammatory and cytoprotective effects of a number of known TSPO ligands, belonging to the class of N,N-dialkyl-2-arylindol-3-ylglyoxylamides (PIGAs), were evaluated, using the classic TSPO ligand PK11195 as the reference standard. All tested PIGAs showed the ability to modulate the inflammatory and apoptotic processes in 661 W photoreceptor-like cells and to reduce LPS-driven cellular cytotoxicity. The protective effect of PIGAs was, in all cases, reduced by cotreatment with the pregnenolone synthesis inhibitor SU-10603, suggesting the involvement of neurosteroids in the protective mechanism. As inflammatory processes play a crucial role in the retinal neurodegenerative disease progression toward photoreceptors' death and complete blindness, targeting TSPO might represent a successful strategy to slow down this degenerative process that may lead to the inexorable loss of vision.
Collapse
|
6
|
Yim A, Smith C, Brown AM. Osteopontin/secreted phosphoprotein-1 harnesses glial-, immune-, and neuronal cell ligand-receptor interactions to sense and regulate acute and chronic neuroinflammation. Immunol Rev 2022; 311:224-233. [PMID: 35451082 PMCID: PMC9790650 DOI: 10.1111/imr.13081] [Citation(s) in RCA: 39] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 04/12/2022] [Accepted: 04/13/2022] [Indexed: 12/31/2022]
Abstract
Osteopontin (OPN) also known by its official gene designation secreted phosphoprotein-1 (SPP1) is a fascinating, multifunctional protein expressed in a number of cell types that functions not only in intercellular communication, but also in the extracellular matrix (ECM). OPN/SPP1 possesses cytokine, chemokine, and signal transduction functions by virtue of modular structural motifs that provide interaction surfaces for integrins and CD44-variant receptors. In humans, there are three experimentally verified splice variants of OPN/SPP1 and CD44's ten exons are also alternatively spiced in a cell/tissue-specific manner, although very little is known about how this is regulated in the central nervous system (CNS). Post-translational modifications of phosphorylation, glycosylation, and localized cleavage by specific proteases in the cells and tissues where OPN/SPP1 functions, provides additional layers of specificity. However, the former make elucidating the exact molecular mechanisms of OPN/SPP1 function more complex. Flexibility in OPN/SPP1 structure and its engagement with integrins having the ability to transmit signals in inside-out and outside-in direction, is likely why OPN/SPP1 can serve as an early detector of inflammation and ongoing tissue damage in response to cancer, stroke, traumatic brain injury, pathogenic infection, and neurodegeneration, processes that impair tissue homeostasis. This review will focus on what is currently known about OPN/SPP1 function in the brain.
Collapse
Affiliation(s)
- Ashley Yim
- NeurologyJohns Hopkins University School of MedicineBaltimoreMarylandUSA
| | - Christian Smith
- NeurologyJohns Hopkins University School of MedicineBaltimoreMarylandUSA
| | - Amanda M. Brown
- NeurologyJohns Hopkins University School of MedicineBaltimoreMarylandUSA
| |
Collapse
|
7
|
Guilarte TR, Rodichkin AN, McGlothan JL, Acanda De La Rocha AM, Azzam DJ. Imaging neuroinflammation with TSPO: A new perspective on the cellular sources and subcellular localization. Pharmacol Ther 2021; 234:108048. [PMID: 34848203 DOI: 10.1016/j.pharmthera.2021.108048] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 11/04/2021] [Accepted: 11/24/2021] [Indexed: 12/14/2022]
Abstract
Translocator Protein 18 kDa (TSPO), previously named Peripheral Benzodiazepine Receptor, is a well-validated and widely used biomarker of neuroinflammation to assess diverse central nervous system (CNS) pathologies in preclinical and clinical studies. Many studies have shown that in animal models of human neurological and neurodegenerative disease and in the human condition, TSPO levels increase in the brain neuropil, and this increase is driven by infiltration of peripheral inflammatory cells and activation of glial cells. Therefore, a clear understanding of the dynamics of the cellular sources of the TSPO response is critically important in the interpretation of Positron Emission Tomography (PET) studies and for understanding the pathophysiology of CNS diseases. Within the normal brain compartment, there are tissues and cells such as the choroid plexus, ependymal cells of the lining of the ventricles, and vascular endothelial cells that also express TSPO at even higher levels than in glial cells. However, there is a paucity of knowledge if these cell types respond and increase TSPO in the diseased brain. These cells do provide a background signal that needs to be accounted for in TSPO-PET imaging studies. More recently, there are reports that TSPO may be expressed in neurons of the adult brain and TSPO expression may be increased by neuronal activity. Therefore, it is essential to study this topic with a great deal of detail, methodological rigor, and rule out alternative interpretations and imaging artifacts. High levels of TSPO are present in the outer mitochondrial membrane. Recent studies have provided evidence of its localization in other cellular compartments including the plasma membrane and perinuclear regions which may define functions that are different from that in mitochondria. A greater understanding of the TSPO subcellular localization in glial cells and infiltrating peripheral immune cells and associated function(s) may provide an additional layer of information to the understanding of TSPO neurobiology. This review is an effort to outline recent advances in understanding the cellular sources and subcellular localization of TSPO in brain cells and to examine remaining questions that require rigorous investigation.
Collapse
Affiliation(s)
- Tomás R Guilarte
- Brain, Behavior, & the Environment Program, Department of Environmental Health Sciences, Robert Stempel College of Public Health & Social Work, Florida International University, Miami, FL 33199, United States of America.
| | - Alexander N Rodichkin
- Brain, Behavior, & the Environment Program, Department of Environmental Health Sciences, Robert Stempel College of Public Health & Social Work, Florida International University, Miami, FL 33199, United States of America
| | - Jennifer L McGlothan
- Brain, Behavior, & the Environment Program, Department of Environmental Health Sciences, Robert Stempel College of Public Health & Social Work, Florida International University, Miami, FL 33199, United States of America
| | - Arlet Maria Acanda De La Rocha
- Brain, Behavior, & the Environment Program, Department of Environmental Health Sciences, Robert Stempel College of Public Health & Social Work, Florida International University, Miami, FL 33199, United States of America
| | - Diana J Azzam
- Brain, Behavior, & the Environment Program, Department of Environmental Health Sciences, Robert Stempel College of Public Health & Social Work, Florida International University, Miami, FL 33199, United States of America
| |
Collapse
|