scholarly journals T cell engagement of cross-presenting microglia protects the brain from a nasal virus infection

2020 ◽  
Vol 5 (48) ◽  
pp. eabb1817 ◽  
Author(s):  
E. Ashley Moseman ◽  
Alexa C. Blanchard ◽  
Debasis Nayak ◽  
Dorian B. McGavern
Keyword(s):  
T Cells ◽  
T Cell ◽  
Calcium Signaling ◽  
Sensory Neurons ◽  
Olfactory Sensory Neurons ◽  
Viral Control ◽  
Mhc I ◽  
Innate Defense ◽  
Barrier Surface ◽  
The Brain

The neuroepithelium is a nasal barrier surface populated by olfactory sensory neurons that detect odorants in the airway and convey this information directly to the brain via axon fibers. This barrier surface is especially vulnerable to infection, yet respiratory infections rarely cause fatal encephalitis, suggesting a highly evolved immunological defense. Here, using a mouse model, we sought to understand the mechanism by which innate and adaptive immune cells thwart neuroinvasion by vesicular stomatitis virus (VSV), a potentially lethal virus that uses olfactory sensory neurons to enter the brain after nasal infection. Fate-mapping studies demonstrated that infected central nervous system (CNS) neurons were cleared noncytolytically, yet specific deletion of major histocompatibility complex class I (MHC I) from these neurons unexpectedly had no effect on viral control. Intravital imaging studies of calcium signaling in virus-specific CD8+ T cells revealed instead that brain-resident microglia were the relevant source of viral peptide–MHC I complexes. Microglia were not infected by the virus but were found to cross-present antigen after acquisition from adjacent neurons. Microglia depletion interfered with T cell calcium signaling and antiviral control in the brain after nasal infection. Collectively, these data demonstrate that microglia provide a front-line defense against a neuroinvasive nasal infection by cross-presenting antigen to antiviral T cells that noncytolytically cleanse neurons. Disruptions in this innate defense likely render the brain susceptible to neurotropic viruses like VSV that attempt to enter the CNS via the nose.

scholarly journals CD8 T Cells and STAT1 Signaling Are Essential Codeterminants in Protection from Polyomavirus Encephalopathy

2020 ◽  
Vol 94 (8) ◽  
Author(s):  
Taryn E. Mockus ◽  
Colleen S. Netherby-Winslow ◽  
Hannah M. Atkins ◽  
Matthew D. Lauver ◽  
Ge Jin ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cd8 T Cells ◽  
Cd8 T Cell ◽  
Chemotherapeutic Agents ◽  
Immune Defense ◽  
Type I ◽  
Viral Control ◽  
Stat1 Signaling ◽  
The Brain

ABSTRACT JC polyomavirus (JCPyV), a human-specific virus, causes the aggressive brain-demyelinating disease progressive multifocal leukoencephalopathy (PML) in individuals with depressed immune status. The increasing incidence of PML in patients receiving immunotherapeutic and chemotherapeutic agents creates a pressing clinical need to define biomarkers to stratify PML risk and develop anti-JCPyV interventions. Mouse polyomavirus (MuPyV) CNS infection causes encephalopathology and may provide insight into JCPyV-PML pathogenesis. Type I, II, and III interferons (IFNs), which all signal via the STAT1 transcription factor, mediate innate and adaptive immune defense against a variety of viral infections. We previously reported that type I and II IFNs control MuPyV infection in non-central nervous system (CNS) organs, but their relative contributions to MuPyV control in the brain remain unknown. To this end, mice deficient in type I, II, or III IFN receptors or STAT1 were infected intracerebrally with MuPyV. We found that STAT1, but not type I, II, or III IFNs, mediated viral control during acute and persistent MuPyV encephalitis. Mice deficient in STAT1 also developed severe hydrocephalus, blood-brain barrier permeability, and increased brain infiltration by myeloid cells. CD8 T cell deficiency alone did not increase MuPyV infection and pathology in the brain. In the absence of STAT1 signaling, however, depletion of CD8 T cells resulted in lytic infection of the choroid plexus and ependymal lining, marked meningitis, and 100% mortality within 2 weeks postinfection. Collectively, these findings indicate that STAT1 signaling and CD8 T cells cocontribute to controlling MuPyV infection in the brain and CNS injury. IMPORTANCE A comprehensive understanding of JCPyV-induced PML pathogenesis is needed to define determinants that predispose patients to PML, a goal whose urgency is heightened by the lack of anti-JCPyV agents. A handicap to achieving this goal is the lack of a tractable animal model to study PML pathogenesis. Using intracerebral inoculation with MuPyV, we found that MuPyV encephalitis in wild-type mice causes an encephalopathy, which is markedly exacerbated in mice deficient in STAT1, a molecule involved in transducing signals from type I, II, and III IFN receptors. CD8 T cell deficiency compounded the severity of MuPyV neuropathology and resulted in dramatically elevated virus levels in the CNS. These findings demonstrate that STAT1 signaling and CD8 T cells concomitantly act to mitigate MuPyV-encephalopathy and control viral infection.

scholarly journals T cells in the brain enhance neonatal mortality during peripheral LCMV infection

2021 ◽  
Vol 17 (1) ◽  
pp. e1009066
Author(s):  
Laurie L. Kenney ◽  
Erik P. Carter ◽  
Anna Gil ◽  
Liisa K. Selin
Keyword(s):  
T Cells ◽  
Viral Load ◽  
T Cell ◽  
Viral Infections ◽  
Cd8 T Cell ◽  
High Viral Load ◽  
Viral Control ◽  
Neonatal Mice ◽  
The Impact ◽  
The Brain

In adult mice the severity of disease from viral infections is determined by the balance between the efficiency of the immune response and the magnitude of viral load. Here, the impact of this dynamic is examined in neonates. Newborns are highly susceptible to infections due to poor innate responses, lower numbers of T cells and Th2-prone immune responses. Eighty-percent of 7-day old mice, immunologically equivalent to human neonates, succumbed to extremely low doses (5 PFU) of the essentially non-lethal lymphocytic choriomeningitis virus (LCMV-Armstrong) given intraperitoneally. This increased lethality was determined to be dependent upon poor early viral control, as well as, T cells and perforin as assessed in knockout mice. By day 3, these neonatal mice had 400-fold higher viral loads as compared to adults receiving a 10,000-fold (5X104 PFU) higher dose of LCMV. The high viral load in combination with the subsequent immunological defect of partial CD8 T cell clonal exhaustion in the periphery led to viral entry and replication in the brain. Within the brain, CD8 T cells were protected from exhaustion, and thus were able to mediate lethal immunopathology. To further delineate the role of early viral control, neonatal mice were infected with Pichinde virus, a less virulent arenavirus, or LCMV was given to pups of LCMV-immune mothers. In both cases, peak viral load was at least 29-fold lower, leading to functional CD8 T cell responses and 100% survival.

scholarly journals Host-derived lipids orchestrate pulmonary γδ T cell response to provide early protection against influenza virus infection

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Xiaohui Wang ◽  
Xiang Lin ◽  
Zihan Zheng ◽  
Bingtai Lu ◽  
Jun Wang ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Viral Infection ◽  
Influenza Virus Infection ◽  
Γδ T Cells ◽  
T Cell Response ◽  
Host Cells ◽  
Interleukin 17 ◽  
Γδ T Cell ◽  
Innate Defense

AbstractInnate immunity is important for host defense by eliciting rapid anti-viral responses and bridging adaptive immunity. Here, we show that endogenous lipids released from virus-infected host cells activate lung γδ T cells to produce interleukin 17 A (IL-17A) for early protection against H1N1 influenza infection. During infection, the lung γδ T cell pool is constantly supplemented by thymic output, with recent emigrants infiltrating into the lung parenchyma and airway to acquire tissue-resident feature. Single-cell studies identify IL-17A-producing γδ T (Tγδ17) cells with a phenotype of TCRγδhiCD3hiAQP3hiCXCR6hi in both infected mice and patients with pneumonia. Mechanistically, host cell-released lipids during viral infection are presented by lung infiltrating CD1d+ B-1a cells to activate IL-17A production in γδ T cells via γδTCR-mediated IRF4-dependent transcription. Reduced IL-17A production in γδ T cells is detected in mice either lacking B-1a cells or with ablated CD1d in B cells. Our findings identify a local host-immune crosstalk and define important cellular and molecular mediators for early innate defense against lung viral infection.

148 Identification of prostate-restricted epithelial antigens for transgenic T cell adoptive therapy against prostate cancer

2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A161-A161
Author(s):  
Diana DeLucia ◽  
Tiffany Pariva ◽  
Roland Strong ◽  
Owen Witte ◽  
John Lee
Keyword(s):  
Prostate Cancer ◽  
T Cells ◽  
T Cell ◽  
Single Cell ◽  
Cd8 T Cells ◽  
Adoptive Therapy ◽  
Mhc I ◽  
Epithelial Antigens ◽  
Ifn Γ ◽  
Stimulation Of

BackgroundIn advanced prostate cancer (PCa), progression to castration-resistant PCa (CRPC) is inevitable and novel therapies for CRPC are needed. Adoptive transfer of T cells targeting tumor antigens is a promising approach in the cancer field. Unfortunately, identifying antigens expressed exclusively in prostate tumor cells has been challenging. Since the prostate is not an essential organ, we alternatively selected prostate-restricted epithelial antigens (PREAs) expressed in both malignant and normal prostate tissue for transgenic T cell studies.MethodsRNA-seq data sets identifying genes enriched in PCa were cross-referenced with the NIH Genotype-Expression database to identify PREAs. Using a novel molecular immunology approach, select PREAs and major histocompatibility complex class I (MHC-I) molecules were co-expressed in HEK293F cells, from which MHC–peptide complexes were efficiently isolated. Peptides were eluted and sequenced by mass spectrometry. Peptide–MHC binding was validated with a T2 stabilization assay and peptide immunodominance was determined using an interferon-γ (IFN-γ) ELISpot assay following stimulation of healthy HLA-A2+ peripheral blood mononuclear cells (PBMC) with peptide pools. Following peptide stimulation, CD8+ T cells with peptide-specific T cell receptors (TCR) were enriched by peptide–MHC-I dextramer labeling and fluorescence activated cell sorting for single cell TCR α/β chain sequencing.ResultsWe identified 11 A2+ peptides (8 previously unpublished) from prostatic acid phosphatase (ACPP), solute carrier family 45 member 3 (SLC45A3), and NK3 homeobox 1 (NKX3.1) that bound to HLA-A2 with varying affinities. Extended culture stimulation of PBMC with peptide pools from each PREA, compared to the standard overnight culture, revealed a greater number of IFN-γ producing cells overall and a greater breadth of response across all the peptides. Antigen specific CD8+ T cells were detectable at low frequencies in both male and female healthy PBMC for 7 of the 11 peptides. Dextramer-sorted antigen-specific cells were used for single-cell paired TCR αβ sequencing and transgenic T cell development.ConclusionsThrough this work we identified HLA-A2-presented antigenic peptides from the PREAs ACPP, SLC45A3, and NKX3.1 that can induce the expansion of IFN-γ producing CD8+ T cells. Through peptide–MHC-I dextramer labeling, we isolated PREA-specific CD8+ T cells and characterized TCR αβ sequences with potential anti-tumor functionality. Our results highlight a rapid and directed platform for the development of MHC-I-restricted transgenic CD8+ T cells targeting lineage-specific proteins expressed in prostate epithelia for adoptive therapy of advanced PCa.

scholarly journals IMMU-28. INDUCTION OF TERTIARY LYMPHOID STRUCTURE-LIKE T-CELL CLUSTERS BY DELIVERY OF A NOVEL GENE COMBINATION INTO AN IMMUNOCOMPETENT MOUSE MODEL OF GLIOBLASTOMA

2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii110-ii111
Author(s):  
Kira Downey ◽  
Bindu Hegde ◽  
Zinal Chheda ◽  
Jason Zhang ◽  
Hideho Okada
Keyword(s):  
T Cells ◽  
T Cell ◽  
Lymphatic Drainage ◽  
Lymphoid Follicle ◽  
Brain Parenchyma ◽  
Cell Therapies ◽  
Gene Combination ◽  
Cell Clustering ◽  
The Brain

Abstract The lack of conventional lymphatic drainage to and from the brain parenchyma restricts the capacity of the peripheral immune system to recognize and respond to glioma antigens. In some peripheral solid tumor types and central nervous system autoimmunity, the spontaneous development of tertiary lymphoid structures (TLS) with varying degrees of organization have been observed in human patients and mice following chronic inflammation. In the cancer setting, presence of TLS are generally associated with improved prognosis, especially when they are characterized by intratumoral infiltration of CD8+ T-cells. We aimed to induce the development of TLS in vivo, utilizing our SB28 glioblastoma model which is sparsely infiltrated by lymphocytes. As a proof-of-concept study, we stably transduced SB28 with a combination of several TLS-stimulating factors that we’ve identified and injected these cells into the brain parenchyma of syngeneic C57BL/6J mice. A combination of the chemoattractant and lymphoid follicle-stimulating cytokines LIGHT, CCL21, IL-7, and IL-17 produced substantial infiltration of CD8+CD3+ T-cells into the tumor and nearby parenchyma. However, this combination was also associated with accelerated tumor growth. A modified gene combination including LIGHT, CCL21, and IL-7 promoted CD8+CD3+ T-cell infiltration by flow cytometry, T-cell clustering by immunofluorescence analysis, and inhibited tumor burden compared with the control as measured by bioluminescent imaging. There was also evidence of increased lymphatic vasculature around the margins of T-cell clustering as demonstrated by LYVE-1 staining. Together, these analyses highlight a role for these factors in stimulating the recruitment and clustering of T-cell to the glioblastoma microenvironment in a TLS-like phenomenon. Future studies will evaluate whether the recruitment of other lymphocytes and stromal cells to these TLS-like clusters can promote T-cell memory and persistence. Ultimately, we aim to provide these factors utilizing a gene delivery method that will prove translatable to the clinic and complementary to existing T-cell therapies.

scholarly journals Conditional deletion of cytokine receptor chains reveals that IL-7 and IL-15 specify CD8 cytotoxic lineage fate in the thymus

2012 ◽  
Vol 209 (12) ◽  
pp. 2263-2276 ◽  
Author(s):  
Tom M. McCaughtry ◽  
Ruth Etzensperger ◽  
Amala Alag ◽  
Xuguang Tai ◽  
Sema Kurtulus ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cd4 T Cells ◽  
Conditional Knockout ◽  
Cytokine Receptor ◽  
T Cell Subsets ◽  
Cytotoxic T Cell ◽  
Lineage Specification ◽  
Class I Mhc ◽  
Mhc I

The thymus generates T cells with diverse specificities and functions. To assess the contribution of cytokine receptors to the differentiation of T cell subsets in the thymus, we constructed conditional knockout mice in which IL-7Rα or common cytokine receptor γ chain (γc) genes were deleted in thymocytes just before positive selection. We found that γc expression was required to signal the differentiation of MHC class I (MHC-I)–specific thymocytes into CD8+ cytotoxic lineage T cells and into invariant natural killer T cells but did not signal the differentiation of MHC class II (MHC-II)–specific thymocytes into CD4+ T cells, even into regulatory Foxp3+CD4+ T cells which require γc signals for survival. Importantly, IL-7 and IL-15 were identified as the cytokines responsible for CD8+ cytotoxic T cell lineage specification in vivo. Additionally, we found that small numbers of aberrant CD8+ T cells expressing Runx3d could arise without γc signaling, but these cells were developmentally arrested before expressing cytotoxic lineage genes. Thus, γc-transduced cytokine signals are required for cytotoxic lineage specification in the thymus and for inducing the differentiation of MHC-I–selected thymocytes into functionally mature T cells.

scholarly journals P06.01 αβ-T cells engineered to express γδ-T cell receptors can kill neuroblastoma organoids independent of MHC-I expression

2021 ◽  
Vol 9 (Suppl 1) ◽  
pp. A19.1-A19
Author(s):  
JGM Strijker ◽  
E Drent ◽  
JJF van der Hoek ◽  
R Pscheid ◽  
B Koopmans ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Cell Receptor ◽  
Healthy Donor ◽  
Transcriptional Profiling ◽  
Cell Receptor ◽  
Γδ T Cell ◽  
Mhc I ◽  
Part Time ◽  
Αβ T Cells

BackgroundCurrently ~50% of patients with the diagnosis of high-risk neuroblastoma will not survive due to relapsing or refractory disease. Recent innovations in immunotherapy for solid tumors are highly promising, but the low MHC-I expression of neuroblastoma represents a major challenge for T cell-mediated immunotherapy. Here, we propose a novel T cell-based immunotherapy approach for neuroblastoma, based on the use of TEG002, αβ-T cells engineered to express a defined γδ-T cell receptor, which are thought to recognize and kill target cells independent of MHC-I. In this pilot project we have tested the potential efficacy of TEG002 therapy as a novel treatment for neuroblastoma, with tumor organoids.Materials and MethodsEffector cells were created from healthy donor peripheral blood T cells. The TEG002 cells were engineered by transducing αβ-T cells with a defined Vγ9Vδ2-T cell receptor. Both the untransduced αβ-T cells and the endogenous Vγ9Vδ2-T cells from the same healthy donor were used as controls in all experiments. Activation and killing of TEG002 was tested in a co-culture setting with neuroblastoma organoids. Supernatant of the co-culture was collected at 24 hours for IFNγ ELISA to measure activation of TEG002. The dynamics of cytotoxicity were analyzed over time from 0 till 72 hours, using the live-cell imaging system IncuCyte from Sartorius®. Killing was quantified using a Caspase3/7 Green dye and the IncuCyte software. Transcriptional profiling of the neuroblastoma organoids was done by RNA sequencing and MHC-I expression of the neuroblastoma organoids was determined by flow cytometry.ResultsWe showed that 3 out of 6 neuroblastoma organoids could activate TEG002 as measured by IFNγ production. Transcriptional profiling of the neuroblastoma organoids showed that this effect correlates with an increased activity of processes involved in interferon signaling and extracellular matrix organization. Analysis of the dynamics of organoid killing by TEG002 over time confirmed that organoids which induced TEG002 activation were efficiently killed independently of their MHC-I expression. Of note, efficacy of TEG002 treatment was superior to donor-matched untransduced αβ-T cells or endogenous γδ-T cells.ConclusionsWe demonstrated that 50% of tested neuroblastoma organoids can effectively activate TEG002 and that killing of the organoids is independent of MHC-I expression. Hence, this pilot study identified TEG002 as a promising novel cellular product for immunotherapy for a subset of neuroblastoma tumors, warranting further investigations into its clinical application.Disclosure InformationJ.G.M. Strijker: None. E. Drent: A. Employment (full or part-time); Significant; Gadeta BV. J.J.F. van der Hoek: None. R. Pscheid: A. Employment (full or part-time); Significant; Gadeta BV. B. Koopmans: None. K. Ober: None. S.R. van Hooff: None. W.M. Kholosy: None. C. Coomans: A. Employment (full or part-time); Significant; Gadeta BV. A. Bisso: A. Employment (full or part-time); Significant; Gadeta BV. M. van Loenen: A. Employment (full or part-time); Significant; Gadeta BV. J.J. Molenaar: None. J. Wienke: None.

scholarly journals Widespread inhibition, antagonism, and synergy in mouse olfactory sensory neurons in vivo

2019 ◽  
Author(s):  
Shigenori Inagaki ◽  
Ryo Iwata ◽  
Masakazu Iwamoto ◽  
Takeshi Imai
Keyword(s):  
Sensory Neurons ◽  
Calcium Imaging ◽  
Odorant Receptor ◽  
Sensory Information ◽  
Olfactory Sensory Neurons ◽  
Axon Terminals ◽  
Two Photon ◽  
Odor Mixtures ◽  
The Brain

SUMMARYSensory information is selectively or non-selectively inhibited and enhanced in the brain, but it remains unclear whether this occurs commonly at the peripheral stage. Here, we performed two-photon calcium imaging of mouse olfactory sensory neurons (OSNs) in vivo and found that odors produce not only excitatory but also inhibitory responses at their axon terminals. The inhibitory responses remained in mutant mice, in which all possible sources of presynaptic lateral inhibition were eliminated. Direct imaging of the olfactory epithelium revealed widespread inhibitory responses at OSN somata. The inhibition was in part due to inverse agonism toward the odorant receptor. We also found that responses to odor mixtures are often suppressed or enhanced in OSNs: Antagonism was dominant at higher odor concentrations, whereas synergy was more prominent at lower odor concentrations. Thus, odor responses are extensively tuned by inhibition, antagonism, and synergy, at the early peripheral stage, contributing to robust odor representations.

scholarly journals αβ-T Cells Engineered to Express γδ-T Cell Receptors Can Kill Neuroblastoma Organoids Independent of MHC-I Expression

2021 ◽  
Vol 11 (9) ◽  
pp. 923
Author(s):  
Josephine G. M. Strijker ◽  
Ronja Pscheid ◽  
Esther Drent ◽  
Jessica J. F. van der Hoek ◽  
Bianca Koopmans ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Transcriptional Profiling ◽  
Γδ T Cells ◽  
Cell Receptor ◽  
Target Cells ◽  
Γδ T Cell ◽  
Mhc I ◽  
Organization Analysis ◽  
Αβ T Cells

Currently ~50% of patients with a diagnosis of high-risk neuroblastoma will not survive due to relapsing or refractory disease. Recent innovations in immunotherapy for solid tumors are highly promising, but the low MHC-I expression of neuroblastoma represents a major challenge for T cell-mediated immunotherapy. Here, we propose a novel T cell-based immunotherapy approach for neuroblastoma, based on the use of TEG002, αβ-T cells engineered to express a defined γδ-T cell receptor, which can recognize and kill target cells independent of MHC-I. In a co-culture killing assay, we showed that 3 out of 6 neuroblastoma organoids could activate TEG002 as measured by IFNγ production. Transcriptional profiling showed this effect correlates with an increased activity of processes involved in interferon signaling and extracellular matrix organization. Analysis of the dynamics of organoid killing by TEG002 over time confirmed that organoids which induced TEG002 activation were efficiently killed independent of their MHC-I expression. Of note, efficacy of TEG002 treatment was superior to donor-matched untransduced αβ-T cells or endogenous γδ-T cells. Our data suggest that TEG002 may be a promising novel treatment option for a subset of neuroblastoma patients.

scholarly journals Brucella Peptide Cross-Reactive MHC I Presentation Activates SIINFEKL-Specific TCR Expressing T Cells

2018 ◽  
Author(s):  
Jerome S. Harms ◽  
Mike Khan ◽  
Cherisse Hall ◽  
Gary A. Splitter ◽  
E. Jane Homan ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Cell Activation ◽  
Pathogenic Bacteria ◽  
Cell Activation ◽  
Immune Surveillance ◽  
Cross Reactivity ◽  
Near Neighbor ◽  
Target Cells ◽  
Mhc I

ABSTRACTBrucella spp are intracellular pathogenic bacteria remarkable in their ability to escape immune surveillance and therefore inflict a state of chronic disease within the host. To enable further immune response studies, Brucella were engineered to express the well characterized chicken ovalbumin (OVA). Surprisingly, we found that CD8 T cells bearing T cell receptors (TCR) nominally specific for the OVA peptide SIINFEKL (OT-1) reacted to parental Brucella-infected targets as well as OVA-expressing Brucella variants in cytotoxicity assays. Furthermore, splenocytes from Brucella immunized mice produced IFN-γ and exhibited cytotoxicity in response to SIINFEKL-pulsed target cells. To determine if the SIINFEKL-reactive OT-1 TCR could be cross-reacting to Brucella peptides, we searched the Brucella proteome using an algorithm to generate a list of near-neighbor nonamer peptides that would bind to H2Kb. Selecting five Brucella peptide candidates, along with controls, we verified that several of these peptides mimicked SIINFEKL resulting in T cell activation through the “SIINFEKL-specific” TCR. Activation was dependent on peptide concentration as well as sequence. Our results underscore the complexity and ubiquity of cross-reactivity in T cell recognition. This cross-reactivity may enable microbes such as Brucella to escape immune surveillance by presenting peptides similar to the host, and may also lead to the activation of autoreactive T cells.

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