This study was supported by grants from the Ministry of Science and Technology (MOST107-2321-B-038-001) and the intramural funding 106TMU-CIT-01-2, Taipei, Taiwan.

Experimental protocols of animal study were approved by the Institutional Animal Care and User Committee of the National Defense Medical Center (IACUC number: 16-261), according to guidelines established by the Ministry of Science and Technology, Taiwan.
1. Infection Procedure
<ol>
	<li>Prepare nonadapted DENV2 (strain PL046) stocks9 (originally obtained from the Centers for Disease Control in Taiwan, ranging from 2.5 x 107 to 1 x 109 PFU/mL).</li>
	<li>Dilute the virus stock to 1 x 106 PFU with Roswell Park Memorial Institute (RPMI) 1640 medium to a total volume of 40 &#956;L.</li>
	<li>Fill one 0.3 mL syringe fitted with a 30 G needle with 10 &#956;L (2.5 x 105 PFU) of diluted virus, and fill another 0.3 mL syringe fitted with a 30 G needle with 30 &#956;L (7.5 x 105 PFU) of diluted virus.</li>
	<li>Hold the 7 day-old ICR suckling mouse and conduct the following steps.
	<ol>
		<li>For the intracerebral injection, hold the mouse in a prone position by pressing the auricle between the index finger and thumb, and intracerebrally inject 10 &#956;L of diluted virus into the lambda area, the point at the intersection of the sagittal and lambdoid suture16.</li>
		<li>After the intracerebral injection, hold the mouse in a supine position by using the index finger and thumb and intraperitoneally inject 30 &#956;L of diluted virus gently into the murine abdomenl. 
		NOTE: To avoid cannibalism, 75% alcohol is used to create a temporary loss of the mother&#8217;s olfactory sensation. Additionally, covering the litters with their mother&#8217;s stool and urine is suggested.</li>
	</ol>
	</li>
	<li>Lay the suckling mice back in their cages and wait for 5 min to check their safety poststimulation with the avidity of mice, including walking and mother milk sucking. 
	NOTE: Most often, mice demonstrate normal activity poststimulation and there does not seem to be any harmful effects following the technical challenge. During this experiment, the animals were maintained by the Institutional Animal Care and User Committee of the National Defense Medical Center, Taiwan.</li>
	<li>Evaluate the daily progress of the mice in terms of body weight (by using a microgram balance), acute viral encephalitis-like disease (by disease scoring as described in section 2), and survival rate9,10,11,12,13,14,15.</li>
</ol>
2. Disease Scoring
<ol>
	<li>Monitor the grade of acute viral encephalitis-like illnesses. Assign a score of 0 to healthy mice; 1 to mice with minor illness symptoms, including weight loss, reduced mobility, and a hunchback body orientation; 2 to mice that exhibit limbic seizure; 3 to mice the exhibit limbic weakness, including moving with difficulty and anterior limb or posterior limb weakness; 4 for paralysis; 5 for death. 
	NOTE: Once the score reaches 3, the disease symptoms are considered to be evolving rapidly.</li>
	<li>Plot the scoring of the disease, according to step 2.1, for each day as a curve-based figure by using the mean &#177; SD of the daily test scores in each group.</li>
</ol>

<ol>
	<li>Guzman, M. G., Gubler, D. J., Izquierdo, A., Martinez, E., Halstead, S. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dengue+infection.">Dengue infection.</a> Nature Reviews Disease Primers. 2, 16055 (2016).</li><li>Katzelnick, L. C., Coloma, J., Harris, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dengue:+knowledge+gaps,+unmet+needs,+and+research+priorities.">Dengue: knowledge gaps, unmet needs, and research priorities.</a> Lancet Infectious Diseases. 17 (3), e88-e100 (2017).</li><li>Carod-Artal, F. J., Wichmann, O., Farrar, J., Gascon, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neurological+complications+of+dengue+virus+infection.">Neurological complications of dengue virus infection.</a> Lancet Neurology. 12 (9), 906-919 (2013).</li><li>Geneva: World Health Organization. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Dengue: Guidelines for Diagnosis, Treatment, Prevention and Control: New Edition. , (2009).</li><li>Amaral, D. C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intracerebral+infection+with+dengue-3+virus+induces+meningoencephalitis+and+behavioral+changes+that+precede+lethality+in+mice.">Intracerebral infection with dengue-3 virus induces meningoencephalitis and behavioral changes that precede lethality in mice.</a> Journal of Neuroinflammation. 8, 23 (2011).</li><li>de Miranda, A. S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dengue-3+encephalitis+promotes+anxiety-like+behavior+in+mice.">Dengue-3 encephalitis promotes anxiety-like behavior in mice.</a> Behavioural Brain Research. 230 (1), 237-242 (2012).</li><li>Velandia-Romero, M. L., Acosta-Losada, O., Castellanos, J. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vivo+infection+by+a+neuroinvasive+neurovirulent+dengue+virus.">In vivo infection by a neuroinvasive neurovirulent dengue virus.</a> Journal of Neurovirology. 18 (5), 374-387 (2012).</li><li>Despres, P., Frenkiel, M. P., Ceccaldi, P. E., Duarte Dos Santos, C., Deubel, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Apoptosis+in+the+mouse+central+nervous+system+in+response+to+infection+with+mouse-neurovirulent+dengue+viruses.">Apoptosis in the mouse central nervous system in response to infection with mouse-neurovirulent dengue viruses.</a> Journal of Virology. 72 (1), 823-829 (1998).</li><li>Tsai, T. T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microglia+retard+dengue+virus-induced+acute+viral+encephalitis.">Microglia retard dengue virus-induced acute viral encephalitis.</a> Scientific Reports. 6, 27670 (2016).</li><li>Cheng, Y. L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Activation+of+Nrf2+by+the+dengue+virus+causes+an+increase+in+CLEC5A,+which+enhances+TNF-alpha+production+by+mononuclear+phagocytes.">Activation of Nrf2 by the dengue virus causes an increase in CLEC5A, which enhances TNF-alpha production by mononuclear phagocytes.</a> Scientific Reports. 6, 32000 (2016).</li><li>Ho, M. R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Blockade+of+dengue+virus+infection+and+viral+cytotoxicity+in+neuronal+cells+in+vitro+and+in+vivo+by+targeting+endocytic+pathways.">Blockade of dengue virus infection and viral cytotoxicity in neuronal cells in vitro and in vivo by targeting endocytic pathways.</a> Scientific Reports. 7 (1), 6910 (2017).</li><li>Jhan, M. K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Anti-TNF-alpha+restricts+dengue+virus-induced+neuropathy.">Anti-TNF-alpha restricts dengue virus-induced neuropathy.</a> Journal of Leukocyte Biology. 104 (5), 961-968 (2018).</li><li>Kao, J. C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+antiparasitic+drug+niclosamide+inhibits+dengue+virus+infection+by+interfering+with+endosomal+acidification+independent+of+mTOR.">The antiparasitic drug niclosamide inhibits dengue virus infection by interfering with endosomal acidification independent of mTOR.</a> PLoS Neglected Tropical Diseases. 12 (8), e0006715 (2018).</li><li>Tsai, T. T., Chen, C. L., Tsai, C. C., Lin, C. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Targeting+heat+shock+factor+1+as+an+antiviral+strategy+against+dengue+virus+replication+in+vitro+and+in+vivo.">Targeting heat shock factor 1 as an antiviral strategy against dengue virus replication in vitro and in vivo.</a> Antiviral Research. 145, 44-53 (2017).</li><li>Jhan, M. K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dengue+virus+infection+increases+microglial+cell+migration.">Dengue virus infection increases microglial cell migration.</a> Scientific Reports. 7 (1), 91 (2017).</li><li>Benskey, M. J., Manfredsson, F. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intraparenchymal+Stereotaxic+Delivery+of+rAAV+and+Special+Considerations+in+Vector+Handling.">Intraparenchymal Stereotaxic Delivery of rAAV and Special Considerations in Vector Handling.</a> Methods in Molecular Biology. , 199-215 (2016).</li><li>Fong, C. Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mild+encephalitis/encephalopathy+with+reversible+splenial+lesion+(MERS)+due+to+dengue+virus.">Mild encephalitis/encephalopathy with reversible splenial lesion (MERS) due to dengue virus.</a> Journal of Clinical Neuroscience. 36, 73-75 (2017).</li><li>Sarathy, V. V., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+lethal+murine+infection+model+for+dengue+virus+3+in+AG129+mice+deficient+in+type+I+and+II+interferon+receptors+leads+to+systemic+disease.">A lethal murine infection model for dengue virus 3 in AG129 mice deficient in type I and II interferon receptors leads to systemic disease.</a> Journal of Virology. 89 (2), 1254-1266 (2015).</li><li>Schul, W., Liu, W., Xu, H. Y., Flamand, M., Vasudevan, S. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+dengue+fever+viremia+model+in+mice+shows+reduction+in+viral+replication+and+suppression+of+the+inflammatory+response+after+treatment+with+antiviral+drugs.">A dengue fever viremia model in mice shows reduction in viral replication and suppression of the inflammatory response after treatment with antiviral drugs.</a> The Journal of Infectious Diseases. 195 (5), 665-674 (2007).</li><li>Tyler, K. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Acute+Viral+Encephalitis.">Acute Viral Encephalitis.</a> New England Journal of Medicine. 379 (6), 557-566 (2018).</li><li>Yauch, L. E., Shresta, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mouse+models+of+dengue+virus+infection+and+disease.">Mouse models of dengue virus infection and disease.</a> Antiviral Research. 80 (2), 87-93 (2008).</li><li>Assir, M. Z., Jawa, A., Ahmed, H. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Expanded+dengue+syndrome:+subacute+thyroiditis+and+intracerebral+hemorrhage.">Expanded dengue syndrome: subacute thyroiditis and intracerebral hemorrhage.</a> BMC Infectious Diseases. 12, 240 (2012).</li><li>Kumar, R., Prakash, O., Sharma, B. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intracranial+hemorrhage+in+dengue+fever:+management+and+outcome:+a+series+of+5+cases+and+review+of+literature.">Intracranial hemorrhage in dengue fever: management and outcome: a series of 5 cases and review of literature.</a> Surgical Neurology. 72 (4), 429-433 (2009).</li><li>Simanjuntak, Y., Liang, J. J., Lee, Y. L., Lin, Y. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Repurposing+of+prochlorperazine+for+use+against+dengue+virus+infection.">Repurposing of prochlorperazine for use against dengue virus infection.</a> Journal of Infectious Diseases. 211 (3), 394-404 (2015).</li><li>Rocha, B. A. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dengue-specific+serotype+related+to+clinical+severity+during+the+2012/2013+epidemic+in+centre+of+Brazil.">Dengue-specific serotype related to clinical severity during the 2012/2013 epidemic in centre of Brazil.</a> Infectious Disease Poverty. 6 (1), 116 (2017).</li></ol>

The authors have nothing to disclose.

DENV infection has been detected in the CNS of severe dengue patients3,17, suggesting the possibility of the manifestation of acute viral encephalitis occurred during dengue pathogenesis. Here, we report an in vivo murine model of DENV infection for studying the involvement of CNS dysfunction in severe dengue, particularly with a focus on DENV-induced acute viral encephalitis-like illnesses. As compared with the previous models, particularly for one-route infecti...

DENV, an arthropod-borne virus of the Flaviviridae family, contains a positive-sense RNA genome that encodes three viral structural proteins (capsid, premembrane, and envelope) and seven viral nonstructural proteins (NS1, NS2A, NS2B, NS3, NS4A, NS4B, and NS5). The four serotypes of DENV (DENV1-4), which infect approximately 390 million people annually, cause a global burden even though governments have directed substantial efforts toward mosquito vector and disease control1. Currently, protective vaccines and therapeutic antiviral drugs are under development and require further long-term validation2. In clinical practice, although a dengue patient with CNS infection is rare, it needs to be further explored to understand the diversity of dengue disease development3. Further investigation and validation are needed; notably, the World Health Organization (WHO) has included the involvement of CNS impairment, such as cognitive impairment, convulsions, encephalopathy, and encephalitis, in the classification of severe dengue3,4. Constructing animal models of DENV infection is indispensable for exploring the neuropathogenesis of DENV infection.
For generating CNS infection by DENV, several studies have executed different routes of DENV infection, including (1) intracerebral inoculation of C57BL/6 mice who received 4 x 103 plaque-forming units (PFU) of nonadapted DENV35,6, (2) intraperitoneal inoculation of BALB/c mice who received 7 x 104 PFU of in vitro neuroadapted DENV47, (3) intracerebral inoculation of Swiss mice who received 1 x 105 PFU of in vivo neuroadapted DENV18, and (4) intracerebral and intraperitoneal co-inoculation of ICR suckling mice who received 1 x 106 PFU of nonadapted DENV29. According to the findings of these studies5,6,7,8,9, DENV infection in mice result in viral replication in the brain, leading to acute viral encephalitis-like syndromes, behavioral changes accompanied by limb paralysis and postural instability, CNS neurotoxicity and inflammation, general and localized plasma leakage through the blood-brain barrier (BBB), and lethality. All the results from these studies5,6,7,8,9 have shown the ability of DENV to infect the CNS and the induction of acute viral encephalitis-like disease following infection.
Based on our current findings9,10,11,12,13,14,15, we have created a murine model of DENV infection as an in vivo platform to examine the therapeutic efficacy of targeted agents/factors against viral replication, as well as neurotoxicity. Here, we report the protocol utilized to create an immunocompetent outbred ICR mouse to study CNS infection and to monitor the development of neuropathies with different severities caused by DENV. The results show the significant progression of encephalitis-like disease in DENV-infected mice in a time-dependent manner.

<table><tbody><tr><td>Roswell Park Memorial Institute 1640 medium (RPMI)</td><td>Gibco</td><td>11875-085</td><td>Diluting virus</td></tr><tr><td>0.3 mL Insulin Syringe&amp;nbsp;</td><td>BD Ultra-Fine&amp;shy;II</td><td>328838</td><td>Intracerebral and intraperitoneal injection</td></tr><tr><td>Microbalance</td><td>METTLER TOLEDO&#039;s LabX</td><td>AL104</td><td>Weight mouse</td></tr><tr><td>Non-adapted DENV2 (strain PL046)</td><td>The Centers for Disease Control of Taiwan</td><td>-</td><td>Infect mouse</td></tr><tr><td>Institute of Cancer Research (ICR) suckling mouse</td><td>BioLASCO Taiwan Co., Ltd</td><td>-</td><td>Our murine model</td></tr></tbody></table>

a murine model of dengue virus-induced acute viral encephalitis-like disease

Dengue virus (DENV), an arthropod-borne virus transmitted by mosquitoes, may cause the severe disease known as dengue hemorrhagic fever, which is characterized by lethal complications due to plasma leakage, ascites, pleural effusion, respiratory distress, severe bleeding, and organ impairment. A few cases of DENV infection present neurological manifestations; however, studies have not explored DENV-induced neuropathogenesis further. In this study, we present a protocol to use an immunocompetent outbred ICR (Institute of Cancer Research) mouse for investigating the induction of central nervous system (CNS) infection with DENV, followed by the progression of acute viral encephalitis-like disease.

Severe dengue-associated neurological complications have been reported in patients for dengue pathogenesis4. Although these cases are rare in the clinic, creating an immunocompetent murine model of DENV infection can be used not only for studying immunopathogenesis but also for exploring CNS infection, neuroinflammation, neurotoxicity, and acute viral encephalitis-like disease. In this study, according to our current model9,<sup c...

Watch this Scientific Journal Video about A Murine Model of Dengue Virus-induced Acute Viral Encephalitis-like Disease at JoVE.com

A Murine Model of Dengue Virus-induced Acute Viral Encephalitis-like Disease

Here, we present a protocol for creating an immunocompetent ICR (Institute of Cancer Research) murine model of central nervous system infection to display the development of neuropathy. Monitoring acute viral encephalitic disorders by identical disease scores could be performed for showing dengue virus-induced neuropathy in vivo.

Dengue virus (DENV), an arthropod-borne virus transmitted by mosquitoes, may cause the severe disease known as dengue hemorrhagic fever, which is ...

a-murine-model-dengue-virus-induced-acute-viral-encephalitis-like

Research

JoVE Journal

Immunology and Infection

6.5K Views.  Taipei Medical University. Here, we present a protocol for creating an immunocompetent ICR (Institute of Cancer Research) murine model of central nervous system infection to display the development of neuropathy. Monitoring acute viral encephalitic disorders by identical disease scores could be performed for showing dengue virus-induced neuropathy in vivo.

Video: A Murine Model of Dengue Virus-induced Acute Viral Encephalitis-like Disease

Induction and Clinical Scoring of Chronic-Relapsing Experimental Autoimmune Encephalomyelitis

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS) that commonly affects young adults. It is characterized by demyelination and glial scaring in areas disseminated in the brain and spinal cord. These lesions alter nerve conduction and induce the disabling neurological deficits that vary with the location of the demyelinated plaques in the CNS (e.g. paraparesis, paralysis, blindness, incontinence).
Experimental autoimmune encephalomyelitis (EAE) is a model for MS. EAE was first induced accidentally in humans during vaccination against rabies, using viruses grown on rabbit spinal cords. Residues of spinal injected with the inactivated virus induced the CNS disease. Following these observations, a first model of EAE was described in non-human primates immunized with a CNS homogenate by Rivers and Schwenther in 1935. EAE has since been generated in a variety of species and can follow different courses depending on the species/strain and immunizing antigen used. For example, immunizing Lewis rats with myelin basic protein in emulsion with adjuvant induces an acute model of EAE, while the same antigen induces a chronic disease in guinea pigs.
The EAE model described here is induced by immunizing DA rats against DA rat spinal cord in emulsion in complete Freund's adjuvant. Rats develop an ascending flaccid paralysis within 7-14 days post-immunization. Clinical signs follow a relapsing-remitting course over several weeks. Pathology shows large immune infiltrates in the CNS and demyelination plaques. Special considerations for taking care for animals with EAE are described at the end of the video.

This video demonstrates the induction and clinical scoring of an animal model of multiple sclerosis: chronic-relapsing experimental autoimmune encephalomyelitis in DA rats. The disease, induced by immunizing rats with an emulsion containing whole rat spinal cord and complete Freund's adjuvant, presents clinical signs resembling the human disease.

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS) that commonly affects young adults. It is characterized by ...

Biology

Myelin Oligodendrocyte Glycoprotein (MOG35-55) Induced Experimental Autoimmune Encephalomyelitis (EAE) in C57BL/6 Mice

Multiple sclerosis is a chronic neuroinflammatory demyelinating disorder of the central nervous system with a strong neurodegenerative component. While the exact etiology of the disease is yet unclear, autoreactive T lymphocytes are thought to play a central role in its pathophysiology. MS therapy is only partially effective so far and research efforts continue to expand our knowledge on the pathophysiology of the disease and to develop novel treatment strategies. Experimental autoimmune encephalomyelitis (EAE) is the most common animal model for MS sharing many clinical and pathophysiological features. There is a broad diversity of EAE models which reflect different clinical, immunological and histological aspects of human MS. Actively-induced EAE in mice is the easiest inducible model with robust and replicable results. It is especially suited for investigating the effects of drugs or of particular genes by using transgenic mice challenged by autoimmune neuroinflammation. Therefore, mice are immunized with CNS homogenates or peptides of myelin proteins. Due to the low immunogenic potential of these peptides, strong adjuvants are used. EAE susceptibility and phenotype depends on the chosen antigen and rodent strain. C57BL/6 mice are the commonly used strain for transgenic mouse construction and respond among others to myelin oligodendrocyte glycoprotein (MOG). The immunogenic epitope MOG35-55 is suspended in complete Freund's adjuvant (CFA) prior to immunization and pertussis toxin is applied on the day of immunization and two days later. Mice develop a "classic" self-limited monophasic EAE with ascending flaccid paralysis within 9-14 days after immunization. Mice are evaluated daily using a clinical scoring system for 25-50 days. Special considerations for care taking of animals with EAE as well as potential applications and limitations of this model are discussed.

Myelin Oligodendrocyte Glycoprotein MOG35-55 Induced Experimental Autoimmune Encephalomyelitis EAE in C57BL/6 Mice

Experimental autoimmune encephalomyelitis (EAE) is an established animal model of multiple sclerosis. C57BL/6 mice are immunized with myelin oligodendrocyte glycoprotein (MOG) peptide 35-55 (MOG35-55), resulting in an ascending flaccid paralysis caused by autoreactive immune cells in the central nervous system. Protocols for disease induction and monitoring will be discussed.

Multiple sclerosis is a chronic neuroinflammatory demyelinating disorder of the central nervous system with a strong neurodegenerative component. While ...

Establishing Mouse Models for Zika Virus-induced Neurological Disorders Using Intracerebral Injection Strategies: Embryonic, Neonatal, and Adult

The Zika virus (ZIKV) is a flavivirus currently endemic in North, Central, and South America. It is now established that the ZIKV can cause microcephaly and additional brain abnormalities. However, the mechanism underlying the pathogenesis of ZIKV in the developing brain remains unclear. Intracerebral surgical methods are frequently used in neuroscience research to address questions about both normal and abnormal brain development and brain function. This protocol utilizes classical surgical techniques and describes methods that allow one to model ZIKV-associated human neurological disease in the mouse nervous system. While direct brain inoculation does not model the normal mode of virus transmission, the method allows investigators to ask targeted questions concerning the consequence after ZIKV infection of the developing brain. This protocol describes embryonic, neonatal, and adult stages of intraventricular inoculation of ZIKV. Once mastered, this method can become a straightforward and reproducible technique that only takes a few hours to perform.

Here we describe a method for establishing a model of Zika virus-induced microcephaly in mouse. This protocol includes methods for embryonic, neonatal, and adult-stage intracerebral inoculation of the Zika virus.

The Zika virus (ZIKV) is a flavivirus currently endemic in North, Central, and South America. It is now established that the ZIKV can cause microcephaly ...

Neuroscience

Rat Model of Widespread Cerebral Cortical Demyelination Induced by an Intracerebral Injection of Pro-Inflammatory Cytokines

Multiple sclerosis (MS) is the most common immune-mediated disease of the central nervous system (CNS) and progressively leads to physical disability and death, caused by white matter lesions in the spinal cord and cerebellum, as well as by demyelination in grey matter. Whilst conventional models of experimental allergic encephalomyelitis are suitable for the investigation of the cell-mediated inflammation in the spinal and cerebellar white matter, they fail to address grey matter pathologies. Here, we present the experimental protocol for a novel rat model of cortical demyelination allowing the investigation of the pathological and molecular mechanisms leading to cortical lesions. The demyelination is induced by an immunization with low-dose myelin oligodendrocyte glycoprotein (MOG) in an incomplete Freund&#39;s adjuvant followed by a catheter-mediated intracerebral delivery of pro-inflammatory cytokines. The catheter, moreover, enables multiple rounds of demyelination without causing injection-induced trauma, as well as the intracerebral delivery of potential therapeutic drugs undergoing a preclinical investigation. The method is also ethically favorable as animal pain and distress or disability are controlled and relatively minimal. The expected timeframe for the implementation of the entire protocol is around 8 - 10 weeks.

The protocol presented here allows the reproduction of a widespread grey matter demyelination of both cortical hemispheres in adult male Dark Agouti rats. The method comprises of intracerebral implantation of a catheter, subclinical immunization against myelin oligodendrocyte glycoprotein, and intracerebral injection of a pro-inflammatory cytokine mixture through the implanted catheter.

Multiple sclerosis (MS) is the most common immune-mediated disease of the central nervous system (CNS) and progressively leads to physical disability and ...

Mouse Footpad Inoculation Model to Study Viral-Induced Neuroinflammatory Responses

This protocol describes a footpad inoculation model used to study the initiation and development of neuroinflammatory responses during alphaherpesvirus infection in mice. As alphaherpesviruses are main invaders of the peripheral nervous system (PNS), this model is suitable to characterize the kinetics of viral replication, its spread from the PNS to CNS, and associated neuroinflammatory responses. The footpad inoculation model allows virus particles to spread from a primary infection site in the footpad epidermis to sensory and sympathetic nerve fibers that innervate the epidermis, sweat glands, and dermis. The infection spreads via the sciatic nerve to the dorsal root ganglia (DRG) and ultimately through the spinal cord to the brain. Here, a mouse footpad is inoculated with pseudorabies virus (PRV), an alphaherpesvirus closely related to herpes simplex virus (HSV) and varicella-zoster virus (VZV). This model demonstrates that PRV infection induces severe inflammation, characterized by neutrophil infiltration in the footpad and DRG. High concentrations of inflammatory cytokines are subsequently detected in homogenized tissues by ELISA. In addition, a strong correlation is observed between PRV gene and protein expression (via qPCR and IF staining) in DRG and the production of pro-inflammatory cytokines. Therefore, the footpad inoculation model provides a better understanding of the processes underlying alphaherpesvirus-induced neuropathies and may lead to the development of innovative therapeutic strategies. In addition, the model can guide research on peripheral neuropathies, such as multiple sclerosis and associated viral-induced damage to the PNS. Ultimately, it can serve as a cost-effective in vivo tool for drug development.

The footpad inoculation model is a valuable tool for characterizing viral-induced neuroinflammatory responses in vivo. In particular, it provides a clear assessment of viral kinetics and associated immunopathological processes initiated in the peripheral nervous system.

This protocol describes a footpad inoculation model used to study the initiation and development of neuroinflammatory responses during alphaherpesvirus ...

A Model for Epilepsy of Infectious Etiology using Theiler's Murine Encephalomyelitis Virus

One of the main causes of epilepsy is an infection of the central nervous system (CNS); approximately 8% of patients who survive such an infection develop epilepsy as a consequence, with rates being significantly higher in less economically developed countries. This work provides an overview of modeling epilepsy of infectious etiology and using it as a platform for novel antiseizure compound testing. A protocol of epilepsy induction by non-stereotactic intracerebral injection of Theiler's murine encephalomyelitis virus (TMEV) in C57BL/6 mice is presented, which replicates many of the early and chronic clinical symptoms of viral encephalitis and subsequent epilepsy in human patients. The clinical evaluation of mice during encephalitis to monitor seizure activity and detect the potential antiseizure effects of novel compounds is described. Furthermore, histopathological consequences of viral encephalitis and seizures such as hippocampal damage and neuroinflammation are shown, as well as long-term consequences such as spontaneous epileptic seizures. The TMEV model is one of the first translational, infection-driven, experimental platforms to allow for the investigation of the mechanisms of epilepsy development as a consequence of CNS infection. Thus, it also serves to identify potential therapeutic targets and compounds for patients at risk of developing epilepsy following a CNS infection.

Intracerebral infection with the Theiler's murine encephalomyelitis virus (TMEV) in C57BL/6 mice replicates many of the early and chronic clinical symptoms of viral encephalitis and subsequent epilepsy in human patients. This paper describes the virus infection, symptoms, and histopathology of the TMEV model.

One of the main causes of epilepsy is an infection of the central nervous system (CNS); approximately 8% of patients who survive such an infection develop ...

Induction and Evaluation of Experimental Autoimmune Encephalomyelitis in Mouse

Modeling Multiple Sclerosis in the Two Sexes: MOG35-55-Induced Experimental Autoimmune Encephalomyelitis

Multiple Sclerosis (MS) is a chronic autoimmune inflammatory disease affecting the central nervous system (CNS). It is characterized by different prevalence in the sexes, affecting more women than men, and different outcomes, showing more aggressive forms in men than in women. Furthermore, MS is highly heterogeneous in terms of clinical aspects, radiological, and pathological features. Thus, it is necessary to take advantage of experimental animal models that allow the investigation of as many aspects of the pathology as possible. Experimental autoimmune encephalomyelitis (EAE) represents one of the most used models of MS in mice, modeling different disease features, from the activation of the immune system to CNS damage. Here we describe a protocol for the induction of EAE in both male and female C57BL/6J mice using myelin oligodendrocyte glycoprotein peptide 35-55 (MOG35-55) immunization, which leads to the development of a chronic form of the disease. We also report the evaluation of the daily clinical score and motor performance of these mice for 28 days post immunization (28 dpi). Lastly, we illustrate some basic histological analysis at the CNS level, focusing on the spinal cord as the primary site of disease-induced damage.

Author Spotlight: Creating a Versatile Experimental Autoimmune Encephalomyelitis Model Relevant for Both Male and Female Mice 

Experimental autoimmune encephalomyelitis is one of the most widely used murine models of multiple sclerosis. In the current protocol, C57BL/6J mice of both sexes are immunized with myelin oligodendrocyte glycoprotein peptide, resulting mainly in ascending paresis of the tail and limbs. Here we discuss the protocol of EAE induction and evaluation.

Multiple Sclerosis (MS) is a chronic autoimmune inflammatory disease affecting the central nervous system (CNS). It is characterized by different ...

Handling-Induced Seizures in a Mouse Model

Source: Batot, G., et al. <a href="https://appjove.unicartagenaproxy.elogim.com/v/63673">A Model for Epilepsy of Infectious Etiology using Theiler&#39;s Murine Encephalomyelitis Virus.</a>&#160;J. Vis. Exp. (2022).
This video demonstrates the induction of handling-induced seizures in a mouse infected with Theiler&#39;s Murine Encephalomyelitis Virus (TMEV). The infected mouse, which has hyperexcitable neurons, is exposed to external physical stimuli. This exposure causes stress, leading to abnormal electrical activity in the neurons, which results in seizures.

Source: Batot, G., et al. A Model for Epilepsy of Infectious Etiology using Theiler&#39;s Murine Encephalomyelitis Virus.&#160;J. Vis. Exp. (2022).
This ...

JoVE Encyclopedia of Experiments

Neuropathology

Epilepsy and Seizure Disorders

Generation of a Murine Model with a Central Nervous System Infection

Source: Shen, T., et al. <a href="https://appjove.unicartagenaproxy.elogim.com/v/59132">A Murine Model of Dengue Virus-induced Acute Viral Encephalitis-like Disease.</a> J. Vis. Exp. (2019)
This video demonstrates the generation of a mouse model with a CNS infection. A suckling pup is injected with the virus both intracranially and intraperitoneally. The virus spreads, infecting the CNS causing neuronal cell death and inflammation. The pup is assessed for symptoms of infection as the disease progresses.

All procedures involving animal models have been reviewed by the local institutional animal care committee and the JoVE veterinary review board.
1. ...

Infectious Diseases

Establishing a Model of Zika Virus-Induced Neurodegeneration in an Adult Mouse

Source: Herrlinger, S. A. et al. <a href="https://appjove.unicartagenaproxy.elogim.com/v/56486">Establishing Mouse Models for Zika Virus-induced Neurological Disorders Using Intracerebral Injection Strategies: Embryonic, Neonatal, and Adult.</a> J. Vis. Exp. (2018)
The video demonstrates intracerebral injection of Zika virus suspension in an adult mouse to induce neurodegeneration. An anesthetized mouse is secured in a stereotaxic frame, and a hole is drilled into the exposed skull for injection. A suspension of the Zika virus is injected into the brain tissue. The viral infection causes inflammation, leading to neurodegeneration.

All procedures involving animal models have been reviewed by the local institutional animal care committee and the JoVE veterinary review board.
1. Adult ...

A Murine Model of Dengue Virus-induced Acute Viral Encephalitis-like Disease

Summary

Explore More Videos