1
|
Pauletti A, Gurlo P, Weiß E, DePaula-Silva AB, Wilcox KS, Bröer S. Viral encephalitis and seizures cause rapid depletion of neuronal progenitor cells and alter neurogenesis in the adult mouse dentate gyrus. Front Cell Neurosci 2025; 18:1528918. [PMID: 39876841 PMCID: PMC11772278 DOI: 10.3389/fncel.2024.1528918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Academic Contribution Register] [Received: 11/15/2024] [Accepted: 12/23/2024] [Indexed: 01/31/2025] Open
Abstract
Infections impacting the central nervous system (CNS) constitute a substantial predisposing factor for the emergence of epileptic seizures. Given that epilepsy conventionally correlates with hippocampal sclerosis and neuronal degeneration, a potentially innovative avenue for therapeutic intervention involves fostering adult neurogenesis, a process primarily occurring within the subgranular zone of the dentate gyrus (DG) through the differentiation of neural stem cells (NSC). While experimental seizures induced by chemoconvulsants or electrical stimulation transiently enhance neurogenesis, the effects of encephalitis and the resultant virus-induced seizures remain inadequately understood. Thus, this study employed the Theiler's Murine Encephalomyelitis Virus (TMEV) model of virus-induced seizures in adult C57BL/6J mice to investigate the impact of infection-induced seizures on neurogenesis at three distinct time points [3, 7, and 14 days post-infection (dpi)]. Immunohistochemical analysis revealed a reduction in the overall number of proliferating cells post-infection. More notably, the specific cell types exhibiting proliferation diverged between TMEV and control (CTR) mice: (1) Neuronal progenitors (doublecortin, DCX+) were almost entirely absent at 3 dpi in the dorsal DG. They resumed proliferation at 14 dpi, but, did not recover to CTR levels, and displayed aberrant migration patterns. (2) The number of proliferating NSCs significantly decreased within the dorsal DG of TMEV mice at 14 dpi compared to CTR, while (3) a heightened population of proliferating astrocytes was observed. Most observed changes were not different between seizing and non-seizing infected mice. In summary, our findings demonstrate that viral infection rapidly depletes neuronal progenitor cells and causes aberrant migration of the remaining ones, potentially contributing to hyperexcitability. Additionally, the increased differentiation toward glial cell fates in infected mice emerges as a possible additional pro-epileptogenic mechanism.
Collapse
Affiliation(s)
- Alberto Pauletti
- School of Veterinary Medicine, Institute of Pharmacology and Toxicology, Freie Universität Berlin, Berlin, Germany
| | - Polina Gurlo
- School of Veterinary Medicine, Institute of Pharmacology and Toxicology, Freie Universität Berlin, Berlin, Germany
| | - Edna Weiß
- School of Veterinary Medicine, Institute of Pharmacology and Toxicology, Freie Universität Berlin, Berlin, Germany
| | | | - Karen S. Wilcox
- Department of Pharmacology and Toxicology, University of Utah, Salt Lake City, UT, United States
| | - Sonja Bröer
- School of Veterinary Medicine, Institute of Pharmacology and Toxicology, Freie Universität Berlin, Berlin, Germany
| |
Collapse
|
2
|
Weiß E, Pauletti A, Egilmez A, Bröer S. Testing perioperative meloxicam analgesia to enhance welfare while preserving model validity in an inflammation-induced seizure model. Sci Rep 2024; 14:30563. [PMID: 39702430 DOI: 10.1038/s41598-024-81925-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Received: 07/04/2024] [Accepted: 11/29/2024] [Indexed: 12/21/2024] Open
Abstract
Despite the international effort to improve laboratory animal welfare through the 3R principles (Reduce, Refine, Replace), many scientists still fail to implement and report their assessment of pain and well-being, likely due to concerns regarding the potential effects of analgesics on experimental outcomes. This study aimed to determine whether refining our viral encephalitis model with perioperative analgesia could enhance well-being and recovery after intracerebral virus infection without impacting disease outcomes. We routinely use the Theiler's Murine Encephalomyelitis Virus (TMEV) model to study virus-induced epilepsy. Given the crucial role of immune cell activation in acute seizure development, we evaluated the effects of the non-steroidal anti-inflammatory drug (NSAID) meloxicam on inflammation, neurodegeneration, and neuronal cell proliferation at 7 days post-infection (dpi). Overall, the impact of virus infection on well-being was less severe than anticipated, and meloxicam treatment did not affect well-being or nest building behavior in TMEV-infected mice. Furthermore, meloxicam treatment did not influence key experimental readouts such as seizure burden, central inflammatory response, neurodegeneration, or neuronal proliferation within the hippocampus. Notably, animals experiencing seizures displayed heightened inflammatory responses and neurodegeneration, which were not influenced by meloxicam treatment. In summary, perioperative analgesia did not compromise key outcome measures such as seizure frequency, inflammation, and neurodegeneration or -regeneration in the TMEV model. However, it also did not add any significant benefits to well-being in the first week after intracranial injections.
Collapse
Affiliation(s)
- Edna Weiß
- Institute of Pharmacology and Toxicology, School of Veterinary Medicine, Freie Universität Berlin, Koserstraße 20, 14195, Berlin, Germany
| | - Alberto Pauletti
- Institute of Pharmacology and Toxicology, School of Veterinary Medicine, Freie Universität Berlin, Koserstraße 20, 14195, Berlin, Germany
| | - Asya Egilmez
- Institute of Pharmacology and Toxicology, School of Veterinary Medicine, Freie Universität Berlin, Koserstraße 20, 14195, Berlin, Germany
| | - Sonja Bröer
- Institute of Pharmacology and Toxicology, School of Veterinary Medicine, Freie Universität Berlin, Koserstraße 20, 14195, Berlin, Germany.
| |
Collapse
|
3
|
Shapaer T, Chen Y, Pan Y, Wu Z, Tang T, Zhao Z, Zeng X. Elevated BEAN1 expression correlates with poor prognosis, immune evasion, and chemotherapy resistance in rectal adenocarcinoma. Discov Oncol 2024; 15:446. [PMID: 39276259 PMCID: PMC11401830 DOI: 10.1007/s12672-024-01321-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Academic Contribution Register] [Received: 07/24/2024] [Accepted: 09/06/2024] [Indexed: 09/16/2024] Open
Abstract
BACKGROUND The BEAN1 gene, primarily studied in neurodegenerative diseases, has been scarcely studied in the context of cancers. Our research examines BEAN1 expression specifically in rectal adenocarcinoma (READ) and its association with prognosis, immune evasion, and chemotherapy resistance. METHODS Data from TCGA and GEO were analyzed to assess BEAN1 levels across various cancer types, with particular emphasis on READ. Functional enrichment, immune infiltration, and treatment response analyses were conducted, followed by validation using patient tissue samples. RESULTS READ tissues exhibited a marked increase in BEAN1 expression compared to normal tissues. Elevated BEAN1 levels were associated with reduced overall survival and increased immune suppression, characterized by elevated M2 macrophage infiltration and reduced CD8+ T cell presence. BEAN1 expression was also linked to higher immune checkpoint genes expression and resistance to immune checkpoint inhibitors and 5-fluorouracil. CONCLUSION This research offers initial evidence that BEAN1 is linked to unfavorable prognosis, immune escape, and resistance to chemotherapy in READ. BEAN1 appears to be a promising new biomarker and potential therapeutic target, warranting further investigation into its potential clinical applications in improving treatment outcomes for READ patients.
Collapse
Affiliation(s)
- Tiannake Shapaer
- Department of Gastrointestinal Surgery, The Affiliated Cancer Hospital of Xinjiang Medical University, Urumqi, 830011, Xinjiang Uygur Autonomous Region, China
| | - Yi Chen
- Department of Breast and Thyroid Surgery, The Affiliated Cancer Hospital of Xinjiang Medical University, Urumqi, 830011, Xinjiang Uygur Autonomous Region, China
| | - Yipeng Pan
- Department of Gastroenterology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, 310020, Zhejiang, China
| | - Zhimin Wu
- Department of Otorhinolaryngology Head and Neck Surgery, Affiliated Hospital of Guizhou Medical University, Guiyang, 550003, Guizhou, China
| | - Tuoxian Tang
- Department of Biology, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Zeliang Zhao
- Department of Gastrointestinal Surgery, The Affiliated Cancer Hospital of Xinjiang Medical University, Urumqi, 830011, Xinjiang Uygur Autonomous Region, China
| | - Xiangyue Zeng
- Department of Gastrointestinal Surgery, The Affiliated Cancer Hospital of Xinjiang Medical University, Urumqi, 830011, Xinjiang Uygur Autonomous Region, China.
| |
Collapse
|
4
|
DePaula-Silva AB. The Contribution of Microglia and Brain-Infiltrating Macrophages to the Pathogenesis of Neuroinflammatory and Neurodegenerative Diseases during TMEV Infection of the Central Nervous System. Viruses 2024; 16:119. [PMID: 38257819 PMCID: PMC10819099 DOI: 10.3390/v16010119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Received: 12/05/2023] [Revised: 01/06/2024] [Accepted: 01/09/2024] [Indexed: 01/24/2024] Open
Abstract
The infection of the central nervous system (CNS) with neurotropic viruses induces neuroinflammation and is associated with the development of neuroinflammatory and neurodegenerative diseases, including multiple sclerosis and epilepsy. The activation of the innate and adaptive immune response, including microglial, macrophages, and T and B cells, while required for efficient viral control within the CNS, is also associated with neuropathology. Under healthy conditions, resident microglia play a pivotal role in maintaining CNS homeostasis. However, during pathological events, such as CNS viral infection, microglia become reactive, and immune cells from the periphery infiltrate into the brain, disrupting CNS homeostasis and contributing to disease development. Theiler's murine encephalomyelitis virus (TMEV), a neurotropic picornavirus, is used in two distinct mouse models: TMEV-induced demyelination disease (TMEV-IDD) and TMEV-induced seizures, representing mouse models of multiple sclerosis and epilepsy, respectively. These murine models have contributed substantially to our understanding of the pathophysiology of MS and seizures/epilepsy following viral infection, serving as critical tools for identifying pharmacological targetable pathways to modulate disease development. This review aims to discuss the host-pathogen interaction during a neurotropic picornavirus infection and to shed light on our current understanding of the multifaceted roles played by microglia and macrophages in the context of these two complexes viral-induced disease.
Collapse
Affiliation(s)
- Ana Beatriz DePaula-Silva
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Utah, Salt Lake City, UT 84112, USA
| |
Collapse
|
5
|
Gadhave DG, Sugandhi VV, Kokare CR. Potential biomaterials and experimental animal models for inventing new drug delivery approaches in the neurodegenerative disorder: Multiple sclerosis. Brain Res 2024; 1822:148674. [PMID: 37952871 DOI: 10.1016/j.brainres.2023.148674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Received: 04/25/2023] [Revised: 09/14/2023] [Accepted: 11/07/2023] [Indexed: 11/14/2023]
Abstract
The tight junction of endothelial cells in the central nervous system (CNS) has an ideal characteristic, acting as a biological barrier that can securely regulate the movement of molecules in the brain. Tightly closed astrocyte cell junctions on blood capillaries are the blood-brain barrier (BBB). This biological barrier prohibits the entry of polar drugs, cells, and ions, which protect the brain from harmful toxins. However, delivering any therapeutic agent to the brain in neurodegenerative disorders (i.e., schizophrenia, multiple sclerosis, etc.) is extremely difficult. Active immune responses such as microglia, astrocytes, and lymphocytes cross the BBB and attack the nerve cells, which causes the demyelination of neurons. Therefore, there is a hindrance in transmitting electrical signals properly, resulting in blindness, paralysis, and neuropsychiatric problems. The main objective of this article is to shed light on the performance of biomaterials, which will help researchers to create nanocarriers that can cross the blood-brain barrier and achieve a therapeutic concentration of drugs in the CNS of patients with multiple sclerosis (MS). The present review focuses on the importance of biomaterials with diagnostic and therapeutic efficacy that can help enhance multiple sclerosis therapeutic potential. Currently, the development of MS in animal models is limited by immune responses, which prevent MS induction in healthy animals. Therefore, this article also showcases animal models currently used for treating MS. A future advance in developing a novel effective strategy for treating MS is now a potential area of research.
Collapse
Affiliation(s)
- Dnyandev G Gadhave
- Department of Pharmaceutics, Sinhgad Technical Education Society's, Sinhgad Institute of Pharmacy (Affiliated to Savitribai Phule Pune University), Narhe, Pune 411041, Maharashtra, India; Department of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, St. John's University, 8000 Utopia Parkway, Queens, NY 11439, USA; Department of Pharmaceutics, Dattakala Shikshan Sanstha's, Dattakala College of Pharmacy (Affiliated to Savitribai Phule Pune University), Swami Chincholi, Daund, Pune 413130, Maharashtra, India.
| | - Vrashabh V Sugandhi
- Department of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, St. John's University, 8000 Utopia Parkway, Queens, NY 11439, USA
| | - Chandrakant R Kokare
- Department of Pharmaceutics, Sinhgad Technical Education Society's, Sinhgad Institute of Pharmacy (Affiliated to Savitribai Phule Pune University), Narhe, Pune 411041, Maharashtra, India
| |
Collapse
|
6
|
Li D, Bühler M, Runft S, Gerold G, Marek K, Baumgärtner W, Strowig T, Gerhauser I. ASC- and caspase-1-deficient C57BL/6 mice do not develop demyelinating disease after infection with Theiler's murine encephalomyelitis virus. Sci Rep 2023; 13:10960. [PMID: 37414913 PMCID: PMC10326010 DOI: 10.1038/s41598-023-38152-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Received: 11/03/2022] [Accepted: 07/04/2023] [Indexed: 07/08/2023] Open
Abstract
Theiler's murine encephalomyelitis virus (TMEV) induces an acute polioencephalomyelitis and a chronic demyelinating leukomyelitis in SJL mice. C57BL/6 (B6) mice generally do not develop TMEV-induced demyelinating disease (TMEV-IDD) due to virus elimination. However, TMEV can persist in specific immunodeficient B6 mice such as IFNβ-/- mice and induce a demyelinating process. The proinflammatory cytokines IL-1β and IL-18 are activated by the inflammasome pathway, which consists of a pattern recognition receptor molecule sensing microbial pathogens, the adaptor molecule Apoptosis-associated speck-like protein containing a CARD (ASC), and the executioner caspase-1. To analyze the contribution of the inflammasome pathway to the resistance of B6 mice to TMEV-IDD, ASC- and caspase-1-deficient mice and wild type littermates were infected with TMEV and investigated using histology, immunohistochemistry, RT-qPCR, and Western Blot. Despite the antiviral activity of the inflammasome pathway, ASC- and caspase-1-deficient mice eliminated the virus and did not develop TMEV-IDD. Moreover, a similar IFNβ and cytokine gene expression was found in the brain of immunodeficient mice and their wild type littermates. Most importantly, Western Blot showed cleavage of IL-1β and IL-18 in all investigated mice. Consequently, inflammasome-dependent activation of IL-1β and IL-18 does not play a major role in the resistance of B6 mice to TMEV-IDD.
Collapse
Affiliation(s)
- Dandan Li
- Department of Pathology, University of Veterinary Medicine Hannover, Foundation, Bünteweg 17, 30559, Hannover, Germany
| | - Melanie Bühler
- Department of Pathology, University of Veterinary Medicine Hannover, Foundation, Bünteweg 17, 30559, Hannover, Germany
| | - Sandra Runft
- Department of Pathology, University of Veterinary Medicine Hannover, Foundation, Bünteweg 17, 30559, Hannover, Germany
| | - Gisa Gerold
- Department of Biochemistry, University of Veterinary Medicine Hannover, Foundation, Bünteweg 17, 30559, Hannover, Germany
- Research Center for Emerging Infections and Zoonoses (RIZ), University of Veterinary Medicine Hannover, Foundation, Bünteweg 17, 30559, Hannover, Germany
- Wallenberg Centre for Molecular Medicine (WCMM), Umeå University, 90185, Umeå, Sweden
- Department of Clinical Microbiology, Virology, Umeå University, 90185, Umeå, Sweden
| | - Katarzyna Marek
- Department of Pathology, University of Veterinary Medicine Hannover, Foundation, Bünteweg 17, 30559, Hannover, Germany
| | - Wolfgang Baumgärtner
- Department of Pathology, University of Veterinary Medicine Hannover, Foundation, Bünteweg 17, 30559, Hannover, Germany
| | - Till Strowig
- Department for Microbial Immune Regulation, Helmholtz Centre for Infection Research, Inhoffenstraße 7, 38124, Braunschweig, Germany
- Hannover Medical School, Carl-Neuberg-Straße 1, 30625, Hannover, Germany
| | - Ingo Gerhauser
- Department of Pathology, University of Veterinary Medicine Hannover, Foundation, Bünteweg 17, 30559, Hannover, Germany.
| |
Collapse
|
7
|
Wannemacher R, Reiß A, Rohn K, Lühder F, Flügel A, Baumgärtner W, Hülskötter K. Ovalbumin-specific CD4 + and CD8 + T cells contribute to different susceptibility for Theiler's murine encephalomyelitis virus persistence. Front Immunol 2023; 14:1194842. [PMID: 37292191 PMCID: PMC10244668 DOI: 10.3389/fimmu.2023.1194842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Academic Contribution Register] [Received: 03/27/2023] [Accepted: 05/12/2023] [Indexed: 06/10/2023] Open
Abstract
Theiler's murine encephalomyelitis virus (TMEV) is the causative agent of TMEV-induced demyelinating disease (TMEV-IDD); a well-established animal model for the chronic progressive form of human multiple sclerosis (MS). In susceptible mice with an inadequate immune response, TMEV-IDD is triggered by virus persistence and maintained by a T cell mediated immunopathology. OT-mice are bred on a TMEV-resistant C57BL/6 background and own predominantly chicken ovalbumin (OVA)-specific populations of CD8+ T cells (OT-I) or CD4+ T cells (OT-II), respectively. It is hypothesized that the lack of antigen specific T cell populations increases susceptibility for a TMEV-infection in OT-mice on a TMEV-resistant C57BL/6 background. OT-I, OT-II, and C57BL/6 control mice were infected intracerebrally with the TMEV-BeAn strain. Mice were scored weekly for clinical disease and after necropsy, histological and immunohistochemical evaluation was performed. OT-I mice started to develop progressive motor dysfunction between 7 and 21 days post infection (dpi), leading up to hind limb paresis and critical weight loss, which resulted in euthanasia for humane reasons between 14 and 35 dpi. OT-I mice displayed a high cerebral virus load, an almost complete absence of CD8+ T cells from the central nervous system (CNS) and a significantly diminished CD4+ T cell response. Contrarily, only 60% (12 of 20) of infected OT-II mice developed clinical disease characterized by mild ataxia. 25% of clinically affected OT-II mice (3 of 12) made a full recovery. 5 of 12 OT-II mice with clinical disease developed severe motor dysfunction similar to OT-I mice and were euthanized for humane reasons between 13 and 37 dpi. OT-II mice displayed only low virus-immunoreactivity, but clinical disease correlated well with severely reduced infiltration of CD8+ T cells and the increased presence of CD4+ T cells in the brains of OT-II mice. Though further studies are needed to reveal the underlying pathomechanisms following TMEV infection in OT mice, findings indicate an immunopathological process as a main contributor to clinical disease in OT-II mice, while a direct virus-associated pathology may be the main contributor to clinical disease in TMEV-infected OT-I mice.
Collapse
Affiliation(s)
- Rouven Wannemacher
- Department of Pathology, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Anna Reiß
- Department of Pathology, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
- Center for Systems Neuroscience, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Karl Rohn
- Department of Biometry, Epidemiology and Data Processing, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Fred Lühder
- Institute of Neuroimmunology and Multiple Sclerosis Research, University Medical Center Göttingen, Göttingen, Germany
| | - Alexander Flügel
- Center for Systems Neuroscience, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
- Institute of Neuroimmunology and Multiple Sclerosis Research, University Medical Center Göttingen, Göttingen, Germany
| | - Wolfgang Baumgärtner
- Department of Pathology, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
- Center for Systems Neuroscience, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Kirsten Hülskötter
- Department of Pathology, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| |
Collapse
|
8
|
Hülskötter K, Lühder F, Leitzen E, Flügel A, Baumgärtner W. CD28-signaling can be partially compensated in CD28-knockout mice but is essential for virus elimination in a murine model of multiple sclerosis. Front Immunol 2023; 14:1105432. [PMID: 37090733 PMCID: PMC10113529 DOI: 10.3389/fimmu.2023.1105432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Received: 11/22/2022] [Accepted: 03/20/2023] [Indexed: 04/08/2023] Open
Abstract
The intracerebral infection of mice with Theiler’s murine encephalomyelitis virus (TMEV) represents a well-established animal model for multiple sclerosis (MS). Because CD28 is the main co-stimulatory molecule for the activation of T cells, we wanted to investigate its impact on the course of the virus infection as well as on a potential development of autoimmunity as seen in susceptible mouse strains for TMEV. In the present study, 5 weeks old mice on a C57BL/6 background with conventional or tamoxifen-induced, conditional CD28-knockout were infected intracerebrally with TMEV-BeAn. In the acute phase at 14 days post TMEV-infection (dpi), both CD28-knockout strains showed virus spread within the central nervous system (CNS) as an uncommon finding in C57BL/6 mice, accompanied by histopathological changes such as reduced microglial activation. In addition, the conditional, tamoxifen-induced CD28-knockout was associated with acute clinical deterioration and weight loss, which limited the observation period for this mouse strain to 14 dpi. In the chronic phase (42 and 147 dpi) of TMEV-infection, surprisingly only 33% of conventional CD28-knockout mice showed chronic TMEV-infection with loss of motor function concomitant with increased spinal cord inflammation, characterized by T- and B cell infiltration, microglial activation and astrogliosis at 33-42 dpi. Therefore, the clinical outcome largely depends on the time point of the CD28-knockout during development of the immune system. Whereas a fatal clinical outcome can already be observed in the early phase during TMEV-infection for conditional, tamoxifen-induced CD28-knockout mice, only one third of conventional CD28-knockout mice develop clinical symptoms later, accompanied by ongoing inflammation and an inability to clear the virus. However, the development of autoimmunity could not be observed in this C57BL/6 TMEV model irrespective of the time point of CD28 deletion.
Collapse
Affiliation(s)
- Kirsten Hülskötter
- Department of Pathology, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Fred Lühder
- Institute for Neuroimmunology and Multiple Sclerosis Research (IMSF), University Medical Center Goettingen, Goettingen, Germany
| | - Eva Leitzen
- Department of Pathology, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Alexander Flügel
- Institute for Neuroimmunology and Multiple Sclerosis Research (IMSF), University Medical Center Goettingen, Goettingen, Germany
| | - Wolfgang Baumgärtner
- Department of Pathology, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
- *Correspondence: Wolfgang Baumgärtner,
| |
Collapse
|
9
|
Viral Clearance and Neuroinflammation in Acute TMEV Infection Vary by Host Genetic Background. Int J Mol Sci 2022; 23:ijms231810482. [PMID: 36142395 PMCID: PMC9501595 DOI: 10.3390/ijms231810482] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Academic Contribution Register] [Received: 08/09/2022] [Revised: 08/30/2022] [Accepted: 08/30/2022] [Indexed: 11/17/2022] Open
Abstract
A wide range of viruses cause neurological manifestations in their hosts. Infection by neurotropic viruses as well as the resulting immune response can irreversibly disrupt the complex structural and functional architecture of the brain, depending in part on host genetic background. The interaction between host genetic background, neurological response to viral infection, and subsequent clinical manifestations remains poorly understood. In the present study, we used the genetically diverse Collaborative Cross (CC) mouse resource to better understand how differences in genetic background drive clinical signs and neuropathological manifestations of acute Theiler's murine encephalomyelitis virus (TMEV) infection. For the first time, we characterized variations of TMEV viral tropism and load based on host genetic background, and correlated viral load with microglial/macrophage activation. For five CC strains (CC002, CC023, CC027, CC057, and CC078) infected with TMEV, we compared clinical signs, lesion distribution, microglial/macrophage response, expression, and distribution of TMEV mRNA, and identified genetic loci relevant to the early acute (4 days post-infection [dpi]) and late acute (14 dpi) timepoints. We examined brain pathology to determine possible causes of strain-specific differences in clinical signs, and found that fields CA1 and CA2 of the hippocampal formation were especially targeted by TMEV across all strains. Using Iba-1 immunolabeling, we identified and characterized strain- and timepoint-specific variation in microglial/macrophage reactivity in the hippocampal formation. Because viral clearance can influence disease outcome, we used RNA in situ hybridization to quantify viral load and TMEV mRNA distribution at both timepoints. TMEV mRNA expression was broadly distributed in the hippocampal formation at 4 dpi in all strains but varied between radiating and clustered distribution depending on the CC strain. We found a positive correlation between microglial/macrophage reactivity and TMEV mRNA expression at 4 dpi. At 14 dpi, we observed a dramatic reduction in TMEV mRNA expression, and localization to the medial portion of field CA1 and field CA2. To better understand how host genetic background can influence pathological outcomes, we identified quantitative trait loci associated with frequency of lesions in a particular brain region and with microglial/macrophage reactivity. These QTL were located near several loci of interest: lysosomal trafficking regulator (Lyst) and nidogen 1 (Nid1), and transmembrane protein 106 B (Tmem106b). Together, these results provide a novel understanding about the influences of genetic variation on the acute neuropathological and immunopathological environment and viral load, which collectively lead to variable disease outcomes. Our findings reveal possible avenues for future investigation which may lead to more effective intervention strategies and treatment regimens.
Collapse
|
10
|
Löscher W, Howe CL. Molecular Mechanisms in the Genesis of Seizures and Epilepsy Associated With Viral Infection. Front Mol Neurosci 2022; 15:870868. [PMID: 35615063 PMCID: PMC9125338 DOI: 10.3389/fnmol.2022.870868] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Academic Contribution Register] [Received: 02/07/2022] [Accepted: 04/05/2022] [Indexed: 12/16/2022] Open
Abstract
Seizures are a common presenting symptom during viral infections of the central nervous system (CNS) and can occur during the initial phase of infection ("early" or acute symptomatic seizures), after recovery ("late" or spontaneous seizures, indicating the development of acquired epilepsy), or both. The development of acute and delayed seizures may have shared as well as unique pathogenic mechanisms and prognostic implications. Based on an extensive review of the literature, we present an overview of viruses that are associated with early and late seizures in humans. We then describe potential pathophysiologic mechanisms underlying ictogenesis and epileptogenesis, including routes of neuroinvasion, viral control and clearance, systemic inflammation, alterations of the blood-brain barrier, neuroinflammation, and inflammation-induced molecular reorganization of synapses and neural circuits. We provide clinical and animal model findings to highlight commonalities and differences in these processes across various neurotropic or neuropathogenic viruses, including herpesviruses, SARS-CoV-2, flaviviruses, and picornaviruses. In addition, we extensively review the literature regarding Theiler's murine encephalomyelitis virus (TMEV). This picornavirus, although not pathogenic for humans, is possibly the best-characterized model for understanding the molecular mechanisms that drive seizures, epilepsy, and hippocampal damage during viral infection. An enhanced understanding of these mechanisms derived from the TMEV model may lead to novel therapeutic interventions that interfere with ictogenesis and epileptogenesis, even within non-infectious contexts.
Collapse
Affiliation(s)
- Wolfgang Löscher
- Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine, Hannover, Germany
- Center for Systems Neuroscience, Hannover, Germany
| | - Charles L. Howe
- Division of Experimental Neurology, Department of Neurology, Mayo Clinic, Rochester, MN, United States
- Center for Multiple Sclerosis and Autoimmune Neurology, Mayo Clinic, Rochester, MN, United States
| |
Collapse
|
11
|
Bühler M, Runft S, Li D, Götting J, Detje CN, Nippold V, Stoff M, Beineke A, Schulz T, Kalinke U, Baumgärtner W, Gerhauser I. IFN-β Deficiency Results in Fatal or Demyelinating Disease in C57BL/6 Mice Infected With Theiler's Murine Encephalomyelitis Viruses. Front Immunol 2022; 13:786940. [PMID: 35222374 PMCID: PMC8864290 DOI: 10.3389/fimmu.2022.786940] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Academic Contribution Register] [Received: 09/30/2021] [Accepted: 01/20/2022] [Indexed: 11/13/2022] Open
Abstract
Type I Interferons (IFN-I) are important inducers of the antiviral immune response and immune modulators. IFN-β is the most highly expressed IFN-I in the central nervous system (CNS). The infection of SJL mice with the BeAn or the DA strain of Theiler's murine encephalomyelitis virus (TMEV) results in a progressive demyelinating disease. C57BL/6 mice are usually resistant to TMEV-induced demyelination and eliminate these strains from the CNS within several weeks. Using C57BL/6 IFN-β knockout (IFN-β-/-) mice infected with TMEV, we evaluated the role of IFN-β in neuroinfection. Despite the resistance of C57BL/6 wild type (WT) mice to TMEV infection, DA-infected IFN-β-/- mice had to be killed at 7 to 8 days post infection (dpi) due to severe clinical disease. In contrast, BeAn-infected IFN-β-/- mice survived until 98 dpi. Nevertheless at 14 dpi, BeAn-infected IFN-β-/- mice showed a stronger encephalitis and astrogliosis, higher viral load as well as higher mRNA levels of Isg15, Eif2ak2 (PKR), Tnfa, Il1b, Il10, Il12 and Ifng in the cerebrum than BeAn-infected WT mice. Moreover, the majority of IFN-β-/- mice did not clear the virus from the CNS and developed mild demyelination in the spinal cord at 98 dpi, whereas virus and lesions were absent in the spinal cord of WT mice. Persistently infected IFN-β-/- mice also had higher Isg15, Eif2ak1, Tnfa, Il1a, Il1b and Ifng mRNA levels in the spinal cord at 98 dpi than their virus-negative counterparts indicating an activation of IFN-I signaling and ongoing inflammation. Most importantly, BeAn-infected NesCre+/- IFN-βfl/fl mice, which do not express IFN-β in neurons, astrocytes and oligodendrocytes, only developed mild brain lesions similar to WT mice. Consequently, IFN-β produced by neuroectodermal cells does not seem to play a critical role in the resistance of C57BL/6 mice against fatal and demyelinating disease induced by TMEV strains.
Collapse
Affiliation(s)
- Melanie Bühler
- University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Sandra Runft
- University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Dandan Li
- University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Jasper Götting
- Institute of Virology, Hannover Medical School, Hannover, Germany
| | - Claudia N Detje
- Institute for Experimental Infection Research, Twincore, Centre for Experimental and Clinical Infection Research, a Joint Venture between the Hannover Medical School and the Helmholtz Centre for Infection Research, Hannover, Germany
| | - Vanessa Nippold
- University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Melanie Stoff
- University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Andreas Beineke
- University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Thomas Schulz
- Institute of Virology, Hannover Medical School, Hannover, Germany
| | - Ulrich Kalinke
- Institute for Experimental Infection Research, Twincore, Centre for Experimental and Clinical Infection Research, a Joint Venture between the Hannover Medical School and the Helmholtz Centre for Infection Research, Hannover, Germany
| | | | - Ingo Gerhauser
- University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| |
Collapse
|
12
|
Howe CL, LaFrance-Corey RG, Overlee BL, Johnson RK, Clarkson BDS, Goddery EN. Inflammatory monocytes and microglia play independent roles in inflammatory ictogenesis. J Neuroinflammation 2022; 19:22. [PMID: 35093106 PMCID: PMC8800194 DOI: 10.1186/s12974-022-02394-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Academic Contribution Register] [Received: 10/07/2021] [Accepted: 01/19/2022] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND The pathogenic contribution of neuroinflammation to ictogenesis and epilepsy may provide a therapeutic target for reduction of seizure burden in patients that are currently underserved by traditional anti-seizure medications. The Theiler's murine encephalomyelitis virus (TMEV) model has provided important insights into the role of inflammation in ictogenesis, but questions remain regarding the relative contribution of microglia and inflammatory monocytes in this model. METHODS Female C57BL/6 mice were inoculated by intracranial injection of 2 × 105, 5 × 104, 1.25 × 104, or 3.125 × 103 plaque-forming units (PFU) of the Daniel's strain of TMEV at 4-6 weeks of age. Infiltration of inflammatory monocytes, microglial activation, and cytokine production were measured at 24 h post-infection (hpi). Viral load, hippocampal injury, cognitive performance, and seizure burden were assessed at several timepoints. RESULTS The intensity of inflammatory infiltration and the extent of hippocampal injury induced during TMEV encephalitis scaled with the amount of infectious virus in the initial inoculum. Cognitive performance was preserved in mice inoculated with 1.25 × 104 PFU TMEV relative to 2 × 105 PFU TMEV, but peak viral load at 72 hpi was equivalent between the inocula. CCL2 production in the brain was attenuated by 90% and TNFα and IL6 production was absent in mice inoculated with 1.25 × 104 PFU TMEV. Acute infiltration of inflammatory monocytes was attenuated by more than 80% in mice inoculated with 1.25 × 104 PFU TMEV relative to 2 × 105 PFU TMEV but microglial activation was equivalent between groups. Seizure burden was attenuated and the threshold to kainic acid-induced seizures was higher in mice inoculated with 1.25 × 104 PFU TMEV but low-level behavioral seizures persisted and the EEG exhibited reduced but detectable abnormalities. CONCLUSIONS The size of the inflammatory monocyte response induced by TMEV scales with the amount of infectious virus in the initial inoculum, despite the development of equivalent peak infectious viral load. In contrast, the microglial response does not scale with the inoculum, as microglial hyper-ramification and increased Iba-1 expression were evident in mice inoculated with either 1.25 × 104 or 2 × 105 PFU TMEV. Inoculation conditions that drive inflammatory monocyte infiltration resulted in robust behavioral seizures and EEG abnormalities, but the low inoculum condition, associated with only microglial activation, drove a more subtle seizure and EEG phenotype.
Collapse
Affiliation(s)
- Charles L Howe
- Department of Neurology, Mayo Clinic, Rochester, MN, 55905, USA.
- Division of Experimental Neurology, Mayo Clinic, Rochester, MN, 55905, USA.
- Translational Neuroimmunology Lab, Mayo Clinic, Guggenheim 1542C, 200 First St SW, Rochester, MN, 55905, USA.
- Center for MS and Autoimmune Neurology, Mayo Clinic, Rochester, MN, 55905, USA.
| | | | - Brittany L Overlee
- Department of Neurology, Mayo Clinic, Rochester, MN, 55905, USA
- Translational Neuroimmunology Lab, Mayo Clinic, Guggenheim 1542C, 200 First St SW, Rochester, MN, 55905, USA
| | - Renee K Johnson
- Department of Neurology, Mayo Clinic, Rochester, MN, 55905, USA
- Translational Neuroimmunology Lab, Mayo Clinic, Guggenheim 1542C, 200 First St SW, Rochester, MN, 55905, USA
| | - Benjamin D S Clarkson
- Department of Neurology, Mayo Clinic, Rochester, MN, 55905, USA
- Translational Neuroimmunology Lab, Mayo Clinic, Guggenheim 1542C, 200 First St SW, Rochester, MN, 55905, USA
- Center for MS and Autoimmune Neurology, Mayo Clinic, Rochester, MN, 55905, USA
| | - Emma N Goddery
- Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic, Rochester, MN, 55905, USA
- Moderna, Cambridge, MA, 02139, USA
| |
Collapse
|
13
|
C-type lectin receptor DCIR contributes to hippocampal injury in acute neurotropic virus infection. Sci Rep 2021; 11:23819. [PMID: 34893671 PMCID: PMC8664856 DOI: 10.1038/s41598-021-03201-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Academic Contribution Register] [Received: 06/07/2021] [Accepted: 11/26/2021] [Indexed: 11/16/2022] Open
Abstract
Neurotropic viruses target the brain and contribute to neurologic diseases. C-type lectin receptors (CLRs) are pattern recognition receptors that recognize carbohydrate structures on endogenous molecules and pathogens. The myeloid CLR dendritic cell immunoreceptor (DCIR) is expressed by antigen presenting cells and mediates inhibitory intracellular signalling. To investigate the effect of DCIR on neurotropic virus infection, mice were infected experimentally with Theiler’s murine encephalomyelitis virus (TMEV). Brain tissue of TMEV-infected C57BL/6 mice and DCIR−/− mice were analysed by histology, immunohistochemistry and RT-qPCR, and spleen tissue by flow cytometry. To determine the impact of DCIR deficiency on T cell responses upon TMEV infection in vitro, antigen presentation assays were utilised. Genetic DCIR ablation in C57BL/6 mice was associated with an ameliorated hippocampal integrity together with reduced cerebral cytokine responses and reduced TMEV loads in the brain. Additionally, absence of DCIR favoured increased peripheral cytotoxic CD8+ T cell responses following TMEV infection. Co-culture experiments revealed that DCIR deficiency enhances the activation of antigen-specific CD8+ T cells by virus-exposed dendritic cells (DCs), indicated by increased release of interleukin-2 and interferon-γ. Results suggest that DCIR deficiency has a supportive influence on antiviral immune mechanisms, facilitating virus control in the brain and ameliorates neuropathology during acute neurotropic virus infection.
Collapse
|
14
|
Hülskötter K, Lühder F, Flügel A, Herder V, Baumgärtner W. Tamoxifen Application Is Associated with Transiently Increased Loss of Hippocampal Neurons following Virus Infection. Int J Mol Sci 2021; 22:8486. [PMID: 34445189 PMCID: PMC8395206 DOI: 10.3390/ijms22168486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Academic Contribution Register] [Received: 07/07/2021] [Revised: 07/27/2021] [Accepted: 08/04/2021] [Indexed: 11/27/2022] Open
Abstract
Tamoxifen is frequently used in murine knockout systems with CreER/LoxP. Besides possible neuroprotective effects, tamoxifen is described as having a negative impact on adult neurogenesis. The present study investigated the effect of a high-dose tamoxifen application on Theiler's murine encephalomyelitis virus (TMEV)-induced hippocampal damage. Two weeks after TMEV infection, 42% of the untreated TMEV-infected mice were affected by marked inflammation with neuronal loss, whereas 58% exhibited minor inflammation without neuronal loss. Irrespective of the presence of neuronal loss, untreated mice lacked TMEV antigen expression within the hippocampus at 14 days post-infection (dpi). Interestingly, tamoxifen application 0, 2 and 4, or 5, 7 and 9 dpi decelerated virus elimination and markedly increased neuronal loss to 94%, associated with increased reactive astrogliosis at 14 dpi. T cell infiltration, microgliosis and expression of water channels were similar within the inflammatory lesions, regardless of tamoxifen application. Applied at 0, 2 and 4 dpi, tamoxifen had a negative impact on the number of doublecortin (DCX)-positive cells within the dentate gyrus (DG) at 14 dpi, without a long-lasting effect on neuronal loss at 147 dpi. Thus, tamoxifen application during a TMEV infection is associated with transiently increased neuronal loss in the hippocampus, increased reactive astrogliosis and decreased neurogenesis in the DG.
Collapse
Affiliation(s)
- Kirsten Hülskötter
- Department of Pathology, University of Veterinary Medicine Hannover, Foundation, 30559 Hannover, Germany; (K.H.); (V.H.)
- Center for Systems Neuroscience, 30559 Hannover, Germany;
| | - Fred Lühder
- Institute for Neuroimmunology and Multiple Sclerosis Research, University Medical Center Göttingen, 37075 Göttingen, Germany;
| | - Alexander Flügel
- Center for Systems Neuroscience, 30559 Hannover, Germany;
- Institute for Neuroimmunology and Multiple Sclerosis Research, University Medical Center Göttingen, 37075 Göttingen, Germany;
| | - Vanessa Herder
- Department of Pathology, University of Veterinary Medicine Hannover, Foundation, 30559 Hannover, Germany; (K.H.); (V.H.)
- Center for Systems Neuroscience, 30559 Hannover, Germany;
| | - Wolfgang Baumgärtner
- Department of Pathology, University of Veterinary Medicine Hannover, Foundation, 30559 Hannover, Germany; (K.H.); (V.H.)
- Center for Systems Neuroscience, 30559 Hannover, Germany;
| |
Collapse
|
15
|
Pavasutthipaisit S, Stoff M, Ebbecke T, Ciurkiewicz M, Mayer-Lambertz S, Störk T, Pavelko KD, Lepenies B, Beineke A. CARD9 Deficiency Increases Hippocampal Injury Following Acute Neurotropic Picornavirus Infection but Does Not Affect Pathogen Elimination. Int J Mol Sci 2021; 22:ijms22136982. [PMID: 34209576 PMCID: PMC8268812 DOI: 10.3390/ijms22136982] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Academic Contribution Register] [Received: 05/03/2021] [Revised: 06/20/2021] [Accepted: 06/25/2021] [Indexed: 12/11/2022] Open
Abstract
Neurotropic viruses target the brain and contribute to neurologic diseases. Caspase recruitment domain containing family member 9 (CARD9) controls protective immunity in a variety of infectious disorders. To investigate the effect of CARD9 in neurotropic virus infection, CARD9−/− and corresponding C57BL/6 wild-type control mice were infected with Theiler’s murine encephalomyelitis virus (TMEV). Brain tissue was analyzed by histology, immunohistochemistry and molecular analyses, and spleens by flow cytometry. To determine the impact of CARD9 deficiency on T cell responses in vitro, antigen presentation assays were utilized. Genetic ablation of CARD9 enhanced early pro-inflammatory cytokine responses and accelerated infiltration of T and B cells in the brain, together with a transient increase in TMEV-infected cells in the hippocampus. CARD9−/− mice showed an increased loss of neuronal nuclear protein+ mature neurons and doublecortin+ neuronal precursor cells and an increase in β-amyloid precursor protein+ damaged axons in the hippocampus. No effect of CARD9 deficiency was found on the initiation of CD8+ T cell responses by flow cytometry and co-culture experiments using virus-exposed dendritic cells or microglia-enriched glial cell mixtures, respectively. The present study indicates that CARD9 is dispensable for the initiation of early antiviral responses and TMEV elimination but may contribute to the modulation of neuroinflammation, thereby reducing hippocampal injury following neurotropic virus infection.
Collapse
Affiliation(s)
- Suvarin Pavasutthipaisit
- Department of Pathology, University of Veterinary Medicine Hannover, 30559 Hannover, Germany; (S.P.); (M.S.); (M.C.); (T.S.)
- Center for Systems Neuroscience, 30559 Hannover, Germany; (T.E.); (B.L.)
- Department of Pathology, Faculty of Veterinary Medicine, Mahanakorn University of Technology, Bangkok 10530, Thailand
| | - Melanie Stoff
- Department of Pathology, University of Veterinary Medicine Hannover, 30559 Hannover, Germany; (S.P.); (M.S.); (M.C.); (T.S.)
| | - Tim Ebbecke
- Center for Systems Neuroscience, 30559 Hannover, Germany; (T.E.); (B.L.)
- Institute for Immunology and Research Center for Emerging Infections and Zoonoses, University of Veterinary Medicine Hannover, 30559 Hannover, Germany;
| | - Malgorzata Ciurkiewicz
- Department of Pathology, University of Veterinary Medicine Hannover, 30559 Hannover, Germany; (S.P.); (M.S.); (M.C.); (T.S.)
| | - Sabine Mayer-Lambertz
- Institute for Immunology and Research Center for Emerging Infections and Zoonoses, University of Veterinary Medicine Hannover, 30559 Hannover, Germany;
| | - Theresa Störk
- Department of Pathology, University of Veterinary Medicine Hannover, 30559 Hannover, Germany; (S.P.); (M.S.); (M.C.); (T.S.)
| | - Kevin D. Pavelko
- Department of Immunology, Mayo Clinic, Rochester, MN 55905, USA;
| | - Bernd Lepenies
- Center for Systems Neuroscience, 30559 Hannover, Germany; (T.E.); (B.L.)
- Institute for Immunology and Research Center for Emerging Infections and Zoonoses, University of Veterinary Medicine Hannover, 30559 Hannover, Germany;
| | - Andreas Beineke
- Department of Pathology, University of Veterinary Medicine Hannover, 30559 Hannover, Germany; (S.P.); (M.S.); (M.C.); (T.S.)
- Center for Systems Neuroscience, 30559 Hannover, Germany; (T.E.); (B.L.)
- Correspondence: ; Tel.: +49-51-195-38640
| |
Collapse
|
16
|
Armando F, Fayyad A, Arms S, Barthel Y, Schaudien D, Rohn K, Gambini M, Lombardo MS, Beineke A, Baumgärtner W, Puff C. Intratumoral Canine Distemper Virus Infection Inhibits Tumor Growth by Modulation of the Tumor Microenvironment in a Murine Xenograft Model of Canine Histiocytic Sarcoma. Int J Mol Sci 2021; 22:ijms22073578. [PMID: 33808256 PMCID: PMC8037597 DOI: 10.3390/ijms22073578] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Academic Contribution Register] [Received: 03/05/2021] [Revised: 03/24/2021] [Accepted: 03/26/2021] [Indexed: 12/18/2022] Open
Abstract
Histiocytic sarcomas refer to highly aggressive tumors with a poor prognosis that respond poorly to conventional treatment approaches. Oncolytic viruses, which have gained significant traction as a cancer therapy in recent decades, represent a promising option for treating histiocytic sarcomas through their replication and/or by modulating the tumor microenvironment. The live attenuated canine distemper virus (CDV) vaccine strain Onderstepoort represents an attractive candidate for oncolytic viral therapy. In the present study, oncolytic virotherapy with CDV was used to investigate the impact of this virus infection on tumor cell growth through direct oncolytic effects or by virus-mediated modulation of the tumor microenvironment with special emphasis on angiogenesis, expression of selected MMPs and TIMP-1 and tumor-associated macrophages in a murine xenograft model of canine histiocytic sarcoma. Treatment of mice with xenotransplanted canine histiocytic sarcomas using CDV induced overt retardation in tumor progression accompanied by necrosis of neoplastic cells, increased numbers of intratumoral macrophages, reduced angiogenesis and modulation of the expression of MMPs and TIMP-1. The present data suggest that CDV inhibits tumor growth in a multifactorial way, including direct cell lysis and reduction of angiogenesis and modulation of MMPs and their inhibitor TIMP-1, providing further support for the concept of its role in oncolytic therapies.
Collapse
Affiliation(s)
- Federico Armando
- Department of Pathology, University of Veterinary Medicine Hannover, Bünteweg 17, 30559 Hannover, Germany; (F.A.); (A.F.); (S.A.); (Y.B.); (M.G.); or (M.S.L.); (A.B.); (C.P.)
| | - Adnan Fayyad
- Department of Pathology, University of Veterinary Medicine Hannover, Bünteweg 17, 30559 Hannover, Germany; (F.A.); (A.F.); (S.A.); (Y.B.); (M.G.); or (M.S.L.); (A.B.); (C.P.)
- Department of Veterinary Medicine, An-Najah National University, Nablus 9720061, Palestine
| | - Stefanie Arms
- Department of Pathology, University of Veterinary Medicine Hannover, Bünteweg 17, 30559 Hannover, Germany; (F.A.); (A.F.); (S.A.); (Y.B.); (M.G.); or (M.S.L.); (A.B.); (C.P.)
| | - Yvonne Barthel
- Department of Pathology, University of Veterinary Medicine Hannover, Bünteweg 17, 30559 Hannover, Germany; (F.A.); (A.F.); (S.A.); (Y.B.); (M.G.); or (M.S.L.); (A.B.); (C.P.)
| | - Dirk Schaudien
- Fraunhofer Institute for Toxicology and Experimental Medicine, Nikolai-Fuchs-Straße 1, 30625 Hannover, Germany;
| | - Karl Rohn
- Institute for Biometry, Epidemiology and Information Processing, University of Veterinary Medicine Hannover, Bünteweg 2, 30559 Hannover, Germany;
| | - Matteo Gambini
- Department of Pathology, University of Veterinary Medicine Hannover, Bünteweg 17, 30559 Hannover, Germany; (F.A.); (A.F.); (S.A.); (Y.B.); (M.G.); or (M.S.L.); (A.B.); (C.P.)
- Dipartimento di Medicina Veterinaria (DIMEVET), Università degli Studi di Milano, Via dell’Università 6, 26900 Lodi, Italy
| | - Mara Sophie Lombardo
- Department of Pathology, University of Veterinary Medicine Hannover, Bünteweg 17, 30559 Hannover, Germany; (F.A.); (A.F.); (S.A.); (Y.B.); (M.G.); or (M.S.L.); (A.B.); (C.P.)
| | - Andreas Beineke
- Department of Pathology, University of Veterinary Medicine Hannover, Bünteweg 17, 30559 Hannover, Germany; (F.A.); (A.F.); (S.A.); (Y.B.); (M.G.); or (M.S.L.); (A.B.); (C.P.)
| | - Wolfgang Baumgärtner
- Department of Pathology, University of Veterinary Medicine Hannover, Bünteweg 17, 30559 Hannover, Germany; (F.A.); (A.F.); (S.A.); (Y.B.); (M.G.); or (M.S.L.); (A.B.); (C.P.)
- Correspondence: ; Tel.: +49-511-953-8620
| | - Christina Puff
- Department of Pathology, University of Veterinary Medicine Hannover, Bünteweg 17, 30559 Hannover, Germany; (F.A.); (A.F.); (S.A.); (Y.B.); (M.G.); or (M.S.L.); (A.B.); (C.P.)
| |
Collapse
|
17
|
Zhang R, Mu J, Chi J, Jiang W, Chi X. The role of picornavirus infection in epileptogenesis. ACTA EPILEPTOLOGICA 2021. [DOI: 10.1186/s42494-021-00040-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Indexed: 11/10/2022] Open
Abstract
AbstractPicornaviridae are a family of small positive-strand RNA viruses, and transmitted via the respiratory or fecal-oral route. The neurotropic picornaviruses can induce acute or late recurrent seizures following central nervous system infection, by infecting the peripheral nerve, crossing the blood-brain barrier and migrating in the Trojan-horse method. Theiler’s murine encephalomyelitis virus (TMEV), as a member of Picornaviridae family, can cause encephalitis, leading to chronic spontaneous seizures. TMEV-infected C57BL/6 mice have been used as an animal model for exploring the mechanism of epileptogenesis and assessing new antiepileptic drugs. Astrogliosis, neuronal death and microglial recruitment have been detected in the hippocampus following the picornaviruse-induced encephalitis. The macrophages, monocytes, neutrophils, as well as IL-6 and TNF-α released by them, play an important role in the epileptogenesis. In this review, we summarize the clinical characteristics of picornavirus infection, and the immunopathology involved in the TMEV-induced epilepsy.
Collapse
|
18
|
Beneficial and Detrimental Effects of Regulatory T Cells in Neurotropic Virus Infections. Int J Mol Sci 2020; 21:ijms21051705. [PMID: 32131483 PMCID: PMC7084400 DOI: 10.3390/ijms21051705] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Academic Contribution Register] [Received: 01/31/2020] [Revised: 02/27/2020] [Accepted: 02/28/2020] [Indexed: 02/07/2023] Open
Abstract
Neurotropic viruses infect the central nervous system (CNS) and cause acute or chronic neurologic disabilities. Regulatory T cells (Treg) play a critical role for immune homeostasis, but may inhibit pathogen-specific immunity in infectious disorders. The present review summarizes the current knowledge about Treg in human CNS infections and their animal models. Besides dampening pathogen-induced immunopathology, Treg have the ability to facilitate protective responses by supporting effector T cell trafficking to the infection site and the development of resident memory T cells. Moreover, Treg can reduce virus replication by inducing apoptosis of infected macrophages and attenuate neurotoxic astrogliosis and pro-inflammatory microglial responses. By contrast, detrimental effects of Treg are caused by suppression of antiviral immunity, allowing for virus persistence and latency. Opposing disease outcomes following Treg manipulation in different models might be attributed to differences in technique and timing of intervention, infection route, genetic background, and the host’s age. In addition, mouse models of virus-induced demyelination revealed that Treg are able to reduce autoimmunity and immune-mediated CNS damage in a disease phase-dependent manner. Understanding the unique properties of Treg and their complex interplay with effector cells represents a prerequisite for the development of new therapeutic approaches in neurotropic virus infections.
Collapse
|
19
|
Bijalwan M, Young CR, Tingling J, Zhou XJ, Rimmelin AR, Leibowitz JL, Welsh CJ. Characterization of Plaque-Sized Variants of Daniel's (DA) Strain in Theiler's Virus-Induced Epilepsy. Sci Rep 2019; 9:3444. [PMID: 30837498 PMCID: PMC6401140 DOI: 10.1038/s41598-019-38967-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Academic Contribution Register] [Received: 04/23/2018] [Accepted: 01/09/2019] [Indexed: 12/20/2022] Open
Abstract
Epilepsy is a complex neurological disease characterized by recurrent seizures. Patients with viral encephalitis have a 16-fold increased risk of developing epilepsy, and this risk can persist for about 15 years after the occurrence of initial viral infection. Theiler's murine encephalomyelitis virus (TMEV) infection induces a well-characterized experimental model of epilepsy in C57BL/6 mice. In response to intracerebral (I.C.) injection of Daniel's (DA) strain of TMEV, there is vigorous immune response, which is detrimental to neurons and contributes to acute seizures, rendering mice susceptible to epilepsy. A comparative in vivo challenge study with either one of the two variants of the DA strain, small (DA-DS) or large (DA-CL) plaque forming variants, revealed differences in the diseases they induced in C57BL/6 mice. Compared to DA-CL-, DA-DS-infected mice exhibited significantly more seizures, higher clinical scores, neuroinflammation, and neuronal damage (mainly in the CA1-CA2 regions of hippocampus). Moreover, the brains of DA-DS infected mice contained approximately five-fold higher virus than those of DA-CL infected mice. A sequence comparison of the DA-CL and DA-DS genome sequences showed mutations in the leader (L) and L* proteins of DA-CL variant, which may be the cause of attenuating phenotype of DA-CL variant in the C57BL/6 mouse model of epilepsy.
Collapse
Affiliation(s)
- M Bijalwan
- Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, College Station, Texas, USA
| | - C R Young
- Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, College Station, Texas, USA
| | - J Tingling
- Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, College Station, Texas, USA
| | - X J Zhou
- Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, College Station, Texas, USA
- College Station High School, Texas A&M Health Science Center, College Station, Texas, USA
| | - A R Rimmelin
- Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, College Station, Texas, USA
| | - J L Leibowitz
- Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, College Station, Texas, USA
- Texas A&M Institute for Neuroscience, Texas A&M University, College Station, Texas, USA
| | - C J Welsh
- Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, College Station, Texas, USA.
- Texas A&M Institute for Neuroscience, Texas A&M University, College Station, Texas, USA.
- Women's Health in Neuroscience Program, Texas A&M Health Science Center, College Station, Texas, USA.
| |
Collapse
|
20
|
Gerhauser I, Hansmann F, Ciurkiewicz M, Löscher W, Beineke A. Facets of Theiler's Murine Encephalomyelitis Virus-Induced Diseases: An Update. Int J Mol Sci 2019; 20:ijms20020448. [PMID: 30669615 PMCID: PMC6358740 DOI: 10.3390/ijms20020448] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Academic Contribution Register] [Received: 12/20/2018] [Revised: 01/15/2019] [Accepted: 01/18/2019] [Indexed: 12/31/2022] Open
Abstract
Theiler’s murine encephalomyelitis virus (TMEV), a naturally occurring, enteric pathogen of mice is a Cardiovirus of the Picornaviridae family. Low neurovirulent TMEV strains such as BeAn cause a severe demyelinating disease in susceptible SJL mice following intracerebral infection. Furthermore, TMEV infections of C57BL/6 mice cause acute polioencephalitis initiating a process of epileptogenesis that results in spontaneous recurrent epileptic seizures in approximately 50% of affected mice. Moreover, C3H mice develop cardiac lesions after an intraperitoneal high-dose application of TMEV. Consequently, TMEV-induced diseases are widely used as animal models for multiple sclerosis, epilepsy, and myocarditis. The present review summarizes morphological lesions and pathogenic mechanisms triggered by TMEV with a special focus on the development of hippocampal degeneration and seizures in C57BL/6 mice as well as demyelination in the spinal cord in SJL mice. Furthermore, a detailed description of innate and adaptive immune responses is given. TMEV studies provide novel insights into the complexity of organ- and mouse strain-specific immunopathology and help to identify factors critical for virus persistence.
Collapse
Affiliation(s)
- Ingo Gerhauser
- Department of Pathology, University of Veterinary Medicine, Bünteweg 17, 30559 Hannover, Germany.
| | - Florian Hansmann
- Department of Pathology, University of Veterinary Medicine, Bünteweg 17, 30559 Hannover, Germany.
- Center for System Neuroscience, 30559 Hannover, Germany.
| | - Malgorzata Ciurkiewicz
- Department of Pathology, University of Veterinary Medicine, Bünteweg 17, 30559 Hannover, Germany.
- Center for System Neuroscience, 30559 Hannover, Germany.
| | - Wolfgang Löscher
- Center for System Neuroscience, 30559 Hannover, Germany.
- Department of Pharmacology, University of Veterinary Medicine, Bünteweg 17, 30559 Hannover, Germany.
| | - Andreas Beineke
- Department of Pathology, University of Veterinary Medicine, Bünteweg 17, 30559 Hannover, Germany.
- Center for System Neuroscience, 30559 Hannover, Germany.
| |
Collapse
|
21
|
Waltl I, Käufer C, Gerhauser I, Chhatbar C, Ghita L, Kalinke U, Löscher W. Microglia have a protective role in viral encephalitis-induced seizure development and hippocampal damage. Brain Behav Immun 2018; 74:186-204. [PMID: 30217535 PMCID: PMC7111316 DOI: 10.1016/j.bbi.2018.09.006] [Citation(s) in RCA: 82] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Academic Contribution Register] [Received: 07/19/2018] [Revised: 08/23/2018] [Accepted: 09/06/2018] [Indexed: 12/12/2022] Open
Abstract
In the central nervous system (CNS), innate immune surveillance is mainly coordinated by microglia. These CNS resident myeloid cells are assumed to help orchestrate the immune response against infections of the brain. However, their specific role in this process and their interactions with CNS infiltrating immune cells, such as blood-borne monocytes and T cells are only incompletely understood. The recent development of PLX5622, a specific inhibitor of colony-stimulating factor 1 receptor that depletes microglia, allows studying the role of microglia in conditions of brain injury such as viral encephalitis, the most common form of brain infection. Here we used this inhibitor in a model of viral infection-induced epilepsy, in which C57BL/6 mice are infected by a picornavirus (Theiler's murine encephalomyelitis virus) and display seizures and hippocampal damage. Our results show that microglia are required early after infection to limit virus distribution and persistence, most likely by modulating T cell activation. Microglia depletion accelerated the occurrence of seizures, exacerbated hippocampal damage, and led to neurodegeneration in the spinal cord, which is normally not observed in this mouse strain. This study enhances our understanding of the role of microglia in viral encephalitis and adds to the concept of microglia-T cell crosstalk.
Collapse
Affiliation(s)
- Inken Waltl
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany,Center for Systems Neuroscience, Hannover, Germany
| | - Christopher Käufer
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany
| | - Ingo Gerhauser
- Department of Pathology, University of Veterinary Medicine Hannover, Germany
| | - Chintan Chhatbar
- Institute for Experimental Infection Research, TWINCORE, Center for Experimental and Clinical Infection Research, a Joint Venture Between the Helmholtz Center for Infection Research, Braunschweig, and the Hannover Medical School, Hannover, Germany
| | - Luca Ghita
- Institute for Experimental Infection Research, TWINCORE, Center for Experimental and Clinical Infection Research, a Joint Venture Between the Helmholtz Center for Infection Research, Braunschweig, and the Hannover Medical School, Hannover, Germany
| | - Ulrich Kalinke
- Center for Systems Neuroscience, Hannover, Germany,Institute for Experimental Infection Research, TWINCORE, Center for Experimental and Clinical Infection Research, a Joint Venture Between the Helmholtz Center for Infection Research, Braunschweig, and the Hannover Medical School, Hannover, Germany
| | - Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany.
| |
Collapse
|
22
|
Anjum SMM, Käufer C, Hopfengärtner R, Waltl I, Bröer S, Löscher W. Automated quantification of EEG spikes and spike clusters as a new read out in Theiler's virus mouse model of encephalitis-induced epilepsy. Epilepsy Behav 2018; 88:189-204. [PMID: 30292054 DOI: 10.1016/j.yebeh.2018.09.016] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Academic Contribution Register] [Received: 06/04/2018] [Revised: 07/13/2018] [Accepted: 09/16/2018] [Indexed: 12/17/2022]
Abstract
Intracerebral infection of C57BL/6 mice with Theiler's murine encephalomyelitis virus (TMEV) replicates many features of viral encephalitis-induced epilepsy in humans, including neuroinflammation, early (insult-associated) and late (spontaneous) seizures, neurodegeneration in the hippocampus, and cognitive and behavioral alterations. Thus, this model may be ideally suited to study mechanisms involved in encephalitis-induced epilepsy as potential targets for epilepsy prevention. However, spontaneous recurrent seizures (SRS) occur too infrequently to be useful as a biomarker of epilepsy, e.g., for drug studies. This prompted us to evaluate whether epileptiform spikes or spike clusters in the cortical electroencephalogram (EEG) may be a useful surrogate of epilepsy in this model. For this purpose, we developed an algorithm that allows efficient and large-scale EEG analysis of early and late seizures, spikes, and spike clusters in the EEG. While 77% of the infected mice exhibited early seizures, late seizures were only observed in 33% of the animals. The clinical characteristics of early and late seizures did not differ except that late generalized convulsive (stage 5) seizures were significantly longer than early stage 5 seizures. Furthermore, the frequency of SRS was much lower than the frequency of early seizures. Continuous (24/7) video-EEG monitoring over several months following infection indicated that the latent period to onset of SRS was 61 (range 16-91) days. Spike and spike clusters were significantly more frequent in infected mice with late seizures than in infected mice without seizures or in mock-infected sham controls. Based on the results of this study, increases in EEG spikes and spike clusters in groups of infected mice may be used as a new readout for studies on antiepileptogenic or disease-modifying drug effects in this model, because the significant increase in average spike counts in mice with late seizures obviously indicates a proepileptogenic alteration.
Collapse
Affiliation(s)
- Syed Muhammad Muneeb Anjum
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany
| | - Christopher Käufer
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany
| | | | - Inken Waltl
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany
| | - Sonja Bröer
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany
| | - Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany.
| |
Collapse
|
23
|
Chemokine receptors CCR2 and CX3CR1 regulate viral encephalitis-induced hippocampal damage but not seizures. Proc Natl Acad Sci U S A 2018; 115:E8929-E8938. [PMID: 30181265 PMCID: PMC6156634 DOI: 10.1073/pnas.1806754115] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Academic Contribution Register] [Indexed: 01/09/2023] Open
Abstract
Viral encephalitis is a major risk factor for the development of seizures, epilepsy, and hippocampal damage with associated cognitive impairment, markedly reducing quality of life in survivors. The mechanisms underlying seizures and hippocampal neurodegeneration developing during and after viral encephalitis are only incompletely understood, hampering the development of preventive treatments. Recent findings suggest that brain invasion of blood-born monocytes may be critically involved in both seizures and brain damage in response to encephalitis, whereas the relative role of microglia, the brain's resident immune cells, in these processes is not clear. CCR2 and CX3CR1 are two chemokine receptors that regulate the responses of myeloid cells, such as monocytes and microglia, during inflammation. We used Ccr2-KO and Cx3cr1-KO mice to understand the role of these receptors in viral encephalitis-associated seizures and neurodegeneration, using the Theiler's virus model of encephalitis in C57BL/6 mice. Our results show that CCR2 as well as CX3CR1 plays a key role in the accumulation of myeloid cells in the CNS and activation of hippocampal myeloid cells upon infection. Furthermore, by using Cx3cr1-creER+/-tdTomatoSt/Wt reporter mice, we show that, with regard to CD45 and CD11b expression, some microglia become indistinguishable from monocytes during CNS infection. Interestingly, the lack of CCR2 or CX3CR1 receptors was associated with almost complete prevention of hippocampal damage but did not prevent seizure development after viral CNS infection. These data are compatible with the hypothesis that CNS inflammatory mechanism(s) other than the infiltrating myeloid cells trigger the development of seizures during viral encephalitis.
Collapse
|
24
|
Uhde AK, Ciurkiewicz M, Herder V, Khan MA, Hensel N, Claus P, Beckstette M, Teich R, Floess S, Baumgärtner W, Jung K, Huehn J, Beineke A. Intact interleukin-10 receptor signaling protects from hippocampal damage elicited by experimental neurotropic virus infection of SJL mice. Sci Rep 2018; 8:6106. [PMID: 29666403 PMCID: PMC5904160 DOI: 10.1038/s41598-018-24378-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Academic Contribution Register] [Received: 10/13/2017] [Accepted: 03/27/2018] [Indexed: 12/24/2022] Open
Abstract
Theiler’s murine encephalomyelitis virus (TMEV) infection represents an experimental mouse model to study hippocampal damage induced by neurotropic viruses. IL-10 is a pleiotropic cytokine with profound anti-inflammatory properties, which critically controls immune homeostasis. In order to analyze IL-10R signaling following virus-induced polioencephalitis, SJL mice were intracerebrally infected with TMEV. RNA-based next generation sequencing revealed an up-regulation of Il10, Il10rα and further genes involved in IL-10 downstream signaling, including Jak1, Socs3 and Stat3 in the brain upon infection. Subsequent antibody-mediated blockade of IL-10R signaling led to enhanced hippocampal damage with neuronal loss and increased recruitment of CD3+ T cells, CD45R+ B cells and an up-regulation of Il1α mRNA. Increased expression of Tgfβ and Foxp3 as well as accumulation of Foxp3+ regulatory T cells and arginase-1+ macrophages/microglia was detected in the hippocampus, representing a potential compensatory mechanism following disturbed IL-10R signaling. Additionally, an increased peripheral Chi3l3 expression was found in spleens of infected mice, which may embody reactive regulatory mechanisms for prevention of excessive immunopathology. The present study highlights the importance of IL-10R signaling for immune regulation and its neuroprotective properties in the context of an acute neurotropic virus infection.
Collapse
Affiliation(s)
- Ann-Kathrin Uhde
- Department of Pathology, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Malgorzata Ciurkiewicz
- Department of Pathology, University of Veterinary Medicine Hannover, Hannover, Germany.,Center for Systems Neuroscience, Hannover, Germany
| | - Vanessa Herder
- Department of Pathology, University of Veterinary Medicine Hannover, Hannover, Germany.,Center for Systems Neuroscience, Hannover, Germany
| | - Muhammad Akram Khan
- Department of Pathology, University of Veterinary Medicine Hannover, Hannover, Germany.,Center for Systems Neuroscience, Hannover, Germany.,Department of Pathobiology, Faculty of Veterinary & Animal Sciences, PMAS-Arid Agriculture University, Rawalpindi, Pakistan
| | - Niko Hensel
- Institute of Neuroanatomy and Cell Biology, Hannover Medical School, Hannover, Germany
| | - Peter Claus
- Center for Systems Neuroscience, Hannover, Germany.,Institute of Neuroanatomy and Cell Biology, Hannover Medical School, Hannover, Germany.,Niedersachsen-Research Network on Neuroinfectiology (N-RENNT), Hannover, Germany
| | - Michael Beckstette
- Experimental Immunology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - René Teich
- Experimental Immunology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Stefan Floess
- Experimental Immunology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Wolfgang Baumgärtner
- Department of Pathology, University of Veterinary Medicine Hannover, Hannover, Germany.,Center for Systems Neuroscience, Hannover, Germany.,Niedersachsen-Research Network on Neuroinfectiology (N-RENNT), Hannover, Germany
| | - Klaus Jung
- Institute for Animal Breeding and Genetics, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Jochen Huehn
- Experimental Immunology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Andreas Beineke
- Department of Pathology, University of Veterinary Medicine Hannover, Hannover, Germany. .,Center for Systems Neuroscience, Hannover, Germany.
| |
Collapse
|
25
|
Macrophage depletion by liposome-encapsulated clodronate suppresses seizures but not hippocampal damage after acute viral encephalitis. Neurobiol Dis 2017; 110:192-205. [PMID: 29208406 DOI: 10.1016/j.nbd.2017.12.001] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Academic Contribution Register] [Received: 08/28/2017] [Revised: 11/09/2017] [Accepted: 12/01/2017] [Indexed: 12/12/2022] Open
Abstract
Viral encephalitis is a major risk factor for the development of seizures and epilepsy, but the underlying mechanisms are only poorly understood. Mouse models such as viral encephalitis induced by intracerebral infection with Theiler's virus in C57BL/6 (B6) mice allow advancing our understanding of the immunological and virological aspects of infection-induced seizures and their treatment. Previous studies using the Theiler's virus model in B6 mice have indicated that brain-infiltrating inflammatory macrophages and the cytokines released by these cells are key to the development of acute seizures and hippocampal damage in this model. However, approaches used to prevent or reduce macrophage infiltration were not specific, so contribution of other mechanisms could not be excluded. In the present study, we used a more selective and widely used approach for macrophage depletion, i.e., systemic administration of clodronate liposomes, to study the contribution of macrophage infiltration to development of seizures and hippocampal damage. By this approach, almost complete depletion of monocytic cells was achieved in spleen and blood of Theiler's virus infected B6 mice, which was associated with a 70% decrease in the number of brain infiltrating macrophages as assessed by flow cytometry. Significantly less clodronate liposome-treated mice exhibited seizures than liposome controls (P<0.01), but the development of hippocampal damage was not prevented or reduced. Clodronate liposome treatment did not reduce the increased Iba1 and Mac3 labeling in the hippocampus of infected mice, indicating that activated microglia may contribute to hippocampal damage. The unexpected mismatch between occurrence of seizures and hippocampal damage is thought-provoking and suggests that the mechanisms involved in degeneration of specific populations of hippocampal neurons in encephalitis-induced epilepsy are more complex than previously thought.
Collapse
|
26
|
Howe CL, LaFrance-Corey RG, Goddery EN, Johnson RK, Mirchia K. Neuronal CCL2 expression drives inflammatory monocyte infiltration into the brain during acute virus infection. J Neuroinflammation 2017; 14:238. [PMID: 29202854 PMCID: PMC5715496 DOI: 10.1186/s12974-017-1015-2] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Academic Contribution Register] [Received: 10/22/2017] [Accepted: 11/27/2017] [Indexed: 12/18/2022] Open
Abstract
Background Viral encephalitis is a dangerous compromise between the need to robustly clear pathogen from the brain and the need to protect neurons from bystander injury. Theiler’s murine encephalomyelitis virus (TMEV) infection of C57Bl/6 mice is a model of viral encephalitis in which the compromise results in hippocampal damage and permanent neurological sequelae. We previously identified brain-infiltrating inflammatory monocytes as the primary driver of this hippocampal pathology, but the mechanisms involved in recruiting these cells to the brain were unclear. Methods Chemokine expression levels in the hippocampus were assessed by microarray, ELISA, RT-PCR, and immunofluorescence. Monocyte infiltration during acute TMEV infection was measured by flow cytometry. CCL2 levels were manipulated by immunodepletion and by specific removal from neurons in mice generated by crossing a line expressing the Cre recombinase behind the synapsin promoter to animals with floxed CCL2. Results Inoculation of the brain with TMEV induced hippocampal production of the proinflammatory chemokine CCL2 that peaked at 6 h postinfection, whereas inoculation with UV-inactivated TMEV did not elicit this response. Immunofluorescence revealed that hippocampal neurons expressed high levels of CCL2 at this timepoint. Genetic deletion of CCR2 and systemic immunodepletion of CCL2 abrogated or blunted the infiltration of inflammatory monocytes into the brain during acute infection. Specific genetic deletion of CCL2 from neurons reduced serum and hippocampal CCL2 levels and inhibited inflammatory monocyte infiltration into the brain. Conclusions We conclude that intracranial inoculation with infectious TMEV rapidly induces the expression of CCL2 in neurons, and this cellular source is necessary for CCR2-dependent infiltration of inflammatory monocytes into the brain during the most acute stage of encephalitis. These findings highlight a unique role for neuronal production of chemokines in the initiation of leukocytic infiltration into the infected central nervous system.
Collapse
Affiliation(s)
- Charles L Howe
- Translational Neuroimmunology Lab, Mayo Clinic, Rochester, USA. .,Center for Multiple Sclerosis and Autoimmune Neurology, Mayo Clinic, Rochester, USA. .,Department of Neurology, Mayo Clinic, Rochester, USA. .,Department of Neuroscience, Mayo Clinic, Rochester, USA. .,Department of Immunology, Mayo Clinic, Rochester, USA. .,Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic, Rochester, USA. .,Mayo Clinic, Guggenheim 1542C, 200 First St SW, Rochester, MN, 55905, USA.
| | - Reghann G LaFrance-Corey
- Translational Neuroimmunology Lab, Mayo Clinic, Rochester, USA.,Department of Neurology, Mayo Clinic, Rochester, USA
| | - Emma N Goddery
- Translational Neuroimmunology Lab, Mayo Clinic, Rochester, USA.,Department of Immunology, Mayo Clinic, Rochester, USA.,Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic, Rochester, USA
| | - Renee K Johnson
- Translational Neuroimmunology Lab, Mayo Clinic, Rochester, USA.,Department of Neurology, Mayo Clinic, Rochester, USA
| | - Kanish Mirchia
- Translational Neuroimmunology Lab, Mayo Clinic, Rochester, USA.,Center for Multiple Sclerosis and Autoimmune Neurology, Mayo Clinic, Rochester, USA.,Department of Neurology, Mayo Clinic, Rochester, USA
| |
Collapse
|
27
|
Kinematic and Electromyographic Activity Changes during Back Squat with Submaximal and Maximal Loading. Appl Bionics Biomech 2017; 2017:9084725. [PMID: 28546738 PMCID: PMC5435978 DOI: 10.1155/2017/9084725] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Academic Contribution Register] [Received: 10/14/2016] [Revised: 02/12/2017] [Accepted: 03/06/2017] [Indexed: 12/20/2022] Open
Abstract
The aim of this study was to investigate the possible kinematic and muscular activity changes with maximal loading during squat maneuver. Fourteen healthy male individuals, who were experienced at performing squats, participated in this study. Each subject performed squats with 80%, 90%, and 100% of the previously established 1 repetition maximum (1RM). Electromyographic (EMG) activities were measured for the vastus lateralis, vastus medialis, rectus femoris, semitendinosus, biceps femoris, gluteus maximus, and erector spinae by using an 8-channel dual-mode portable EMG and physiological signal data acquisition system (Myomonitor IV, Delsys Inc., Boston, MA, USA). Kinematical data were analyzed by using saSuite 2D kinematical analysis program. Data were analyzed with repeated measures analysis of variance (p < 0.05). Overall muscle activities increased with increasing loads, but significant increases were seen only for vastus medialis and gluteus maximus during 90% and 100% of 1RM compared to 80% while there was no significant difference between 90% and 100% for any muscle. The movement pattern in the hip joint changed with an increase in forward lean during maximal loading. Results may suggest that maximal loading during squat may not be necessary for focusing on knee extensor improvement and may increase the lumbar injury risk.
Collapse
|