Dr. Pinto is funded by a seed grant from the Saint Louis University School of Medicine and startup funds from Saint Louis University School of Medicine. Dr. Brien is funded by a K22AI104794 early investigator award from the NIH NIAID as well a seed grant from the Saint Louis University School. For all funded individuals the funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

All procedures of the present study are in accordance with the guidelines set by the St. Louis University Animal Care and Use Committee. SLU is fully accredited by the Association for Assessment and Accreditation of Laboratory Animal Care International (AAALAC).
1. Organ Isolation
NOTE: The virus is not stable at room temperature (RT) so the number of animals harvested at one time must be planned carefully to preserve viral titers.
<ol>
	<li><stro...

<ol>
	<li>Lazear, H. M., Diamond, M. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Zika+Virus:+New+Clinical+Syndromes+and+Its+Emergence+in+the+Western+Hemisphere.">Zika Virus: New Clinical Syndromes and Its Emergence in the Western Hemisphere.</a> Journal of Virology. 90 (10), 4864-4875 (2016).</li><li>Simpson, D. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Zika+Virus+Infection+in+Man.">Zika Virus Infection in Man.</a> Transactions of the Royal Society of Tropical Medicine and Hygiene. 58, 335-338 (1964).</li><li>Fagbami, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Epidemiological+investigations+on+arbovirus+infections+at+Igbo-Ora,+Nigeria.">Epidemiological investigations on arbovirus infections at Igbo-Ora, Nigeria.</a> Tropical and Geographical Medicine. 29 (2), 187-191 (1977).</li><li>McCrae, A. W., Kirya, B. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Yellow+fever+and+Zika+virus+epizootics+and+enzootics+in+Uganda.">Yellow fever and Zika virus epizootics and enzootics in Uganda.</a> Transactions of the Royal Society of Tropical Medicine and Hygiene. 76 (4), 552-562 (1982).</li><li>Rodhain, F., 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=Arbovirus+infections+and+viral+haemorrhagic+fevers+in+Uganda:+a+serological+survey+in+Karamoja+district,+1984.">Arbovirus infections and viral haemorrhagic fevers in Uganda: a serological survey in Karamoja district, 1984.</a> Transactions of the Royal Society of Tropical Medicine and Hygiene. 83 (6), 851-854 (1984).</li><li>Wikan, N., Smith, D. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Zika+virus:+history+of+a+newly+emerging+arbovirus.">Zika virus: history of a newly emerging arbovirus.</a> Lancet Infect Dis. 16 (7), e119-e126 (2016).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Zika+virus+outbreaks+in+the+Americas.">Zika virus outbreaks in the Americas.</a> The Weekly Epidemiological Record. 90 (45), 609-610 (2015).</li><li>Brien, J. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Immunological basis of age-related vulnerability to viral infection. , (2007).</li><li>Brien, J. D., Uhrlaub, J. L., Nikolich-Zugich, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=West+Nile+virus-specific+CD4+T+cells+exhibit+direct+antiviral+cytokine+secretion+and+cytotoxicity+and+are+sufficient+for+antiviral+protection.">West Nile virus-specific CD4 T cells exhibit direct antiviral cytokine secretion and cytotoxicity and are sufficient for antiviral protection.</a> Journal of Immunology. 181 (12), 8568-8575 (2008).</li><li>Brien, J. D., Uhrlaub, J. L., Hirsch, A., Wiley, C. A., Nikolich-Zugich, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Key+role+of+T+cell+defects+in+age-related+vulnerability+to+West+Nile+virus.">Key role of T cell defects in age-related vulnerability to West Nile virus.</a> Journal of Experimental Medicine. 206 (12), 2735-2745 (2009).</li><li>Brien, J. D., 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=Genotype-specific+neutralization+and+protection+by+antibodies+against+dengue+virus+type+3.">Genotype-specific neutralization and protection by antibodies against dengue virus type 3.</a> Journal of Virology. 84 (20), 10630-10643 (2010).</li><li>Shrestha, B., 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+development+of+therapeutic+antibodies+that+neutralize+homologous+and+heterologous+genotypes+of+dengue+virus+type+1.">The development of therapeutic antibodies that neutralize homologous and heterologous genotypes of dengue virus type 1.</a> PLoS Pathogens. 6 (4), e1000823 (2010).</li><li>Brien, J. D., 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=Interferon+regulatory+factor-1+(IRF-1)+shapes+both+innate+and+CD8(+)+T+cell+immune+responses+against+West+Nile+virus+infection.">Interferon regulatory factor-1 (IRF-1) shapes both innate and CD8(+) T cell immune responses against West Nile virus infection.</a> PLoS Pathogens. 7 (9), e1002230 (2011).</li><li>Pinto, A. 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=A+temporal+role+of+type+I+interferon+signaling+in+CD8++T+cell+maturation+during+acute+West+Nile+virus+infection.">A temporal role of type I interferon signaling in CD8+ T cell maturation during acute West Nile virus infection.</a> PLoS Pathogens. 7 (12), e1002407 (2011).</li><li>Brien, J. D., Lazear, H. M., Diamond, M. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Propagation,+quantification,+detection,+and+storage+of+West+Nile+virus.">Propagation, quantification, detection, and storage of West Nile virus.</a> Current Protocols in Microbiology. 31, 11-15 (2013).</li><li>Brien, J. D., 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=Protection+by+immunoglobulin+dual-affinity+retargeting+antibodies+against+dengue+virus.">Protection by immunoglobulin dual-affinity retargeting antibodies against dengue virus.</a> Journal of Virology. 87 (13), 7747-7753 (2013).</li><li>Messaoudi, I., 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=Chikungunya+virus+infection+results+in+higher+and+persistent+viral+replication+in+aged+rhesus+macaques+due+to+defects+in+anti-viral+immunity.">Chikungunya virus infection results in higher and persistent viral replication in aged rhesus macaques due to defects in anti-viral immunity.</a> PLoS Neglected Tropical Diseases. 7 (7), e2343 (2013).</li><li>Pinto, A. 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=A+hydrogen+peroxide-inactivated+virus+vaccine+elicits+humoral+and+cellular+immunity+and+protects+against+lethal+West+Nile+virus+infection+in+aged+mice.">A hydrogen peroxide-inactivated virus vaccine elicits humoral and cellular immunity and protects against lethal West Nile virus infection in aged mice.</a> Journal of Virology. 87 (4), 1926-1936 (2013).</li><li>Sukupolvi-Petty, 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=Functional+analysis+of+antibodies+against+dengue+virus+type+4+reveals+strain-dependent+epitope+exposure+that+impacts+neutralization+and+protection.">Functional analysis of antibodies against dengue virus type 4 reveals strain-dependent epitope exposure that impacts neutralization and protection.</a> Journal of Virology. 87 (16), 8826-8842 (2013).</li><li>Pinto, A. 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=Deficient+IFN+signaling+by+myeloid+cells+leads+to+MAVS-dependent+virus-induced+sepsis.">Deficient IFN signaling by myeloid cells leads to MAVS-dependent virus-induced sepsis.</a> PLoS Pathogens. 10 (4), e1004086 (2014).</li><li>Pinto, A. 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=Defining+New+Therapeutics+Using+a+More+Immunocompetent+Mouse+Model+of+Antibody-Enhanced+Dengue+Virus+Infection.">Defining New Therapeutics Using a More Immunocompetent Mouse Model of Antibody-Enhanced Dengue Virus Infection.</a> MBio. 6 (5), (2015).</li><li>Pinto, A. 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=Human+and+Murine+IFIT1+Proteins+Do+Not+Restrict+Infection+of+Negative-Sense+RNA+Viruses+of+the+Orthomyxoviridae,+Bunyaviridae,+and+Filoviridae+Families.">Human and Murine IFIT1 Proteins Do Not Restrict Infection of Negative-Sense RNA Viruses of the Orthomyxoviridae, Bunyaviridae, and Filoviridae Families.</a> Journal of Virology. 89 (18), 9465-9476 (2015).</li><li>Hassert, 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=CD4+T+cells+mediate+protection+against+Zika+associated+severe+disease+in+a+mouse+model+of+infection.">CD4+T cells mediate protection against Zika associated severe disease in a mouse model of infection.</a> PLoS Pathog. 14 (9), e1007237 (2018).</li><li>Pinto, A. 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=Deficient+IFN+signaling+by+myeloid+cells+leads+to+MAVS-dependent+virus-induced+sepsis.">Deficient IFN signaling by myeloid cells leads to MAVS-dependent virus-induced sepsis.</a> PLoS Pathog. 10 (4), e1004086 (2014).</li><li>Brien, J. D., Lazear, H. M., Diamond, M. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Propagation,+quantification,+detection,+and+storage+of+West+Nile+virus.">Propagation, quantification, detection, and storage of West Nile virus.</a> Curr Protoc Microbiol. 31, (2013).</li><li>Hassert, 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=CD4+T+cells+mediate+protection+against+Zika+associated+severe+disease+in+a+mouse+model+of+infection.">CD4+T cells mediate protection against Zika associated severe disease in a mouse model of infection.</a> PLoS Pathogens. 14 (9), e1007237 (2018).</li><li>Fuchs, A., Pinto, A. K., Schwaeble, W. J., Diamond, M. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+lectin+pathway+of+complement+activation+contributes+to+protection+from+West+Nile+virus+infection.">The lectin pathway of complement activation contributes to protection from West Nile virus infection.</a> Virology. 412 (1), 101-109 (2011).</li><li>Lazear, H. M., Pinto, A. K., Vogt, M. R., Gale, M., Diamond, M. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Beta+interferon+controls+West+Nile+virus+infection+and+pathogenesis+in+mice.">Beta interferon controls West Nile virus infection and pathogenesis in mice.</a> Journal of Virology. 85 (14), 7186-7194 (2011).</li></ol>

ZIKV infection can cause a neurological disease therefore the current animal models to study pathogenesis, immune responses and protective efficacy of vaccines and antivirals need to focus on viral control within the CNS. One of the challenges in focusing on CNS disease is that it often comes at the expense of studying peripheral infection. The organ isolation methods proposed here focuses on the need to rapidly evaluate ZIKV infection in both the periphery and the CNS in order to assess CNS mediated ZIKV associated dise...

Zika virus (ZIKV) is an arbovirus that belongs to the flaviviridae family, which includes important neuroinvasive human pathogens such as Powassan virus (POWV), Japanese encephalitis virus (JEV), and West Nile virus (WNV)1. Following its isolation and identification, there have been periodic reports of human ZIKV infections in Africa and Asia2,3,4,5, and epidemics within Central and South America (reviewed in reference6). However, it was not until recently that ZIKV was thought to cause severe disease7. Now there are thousands of cases of neurological disease and birth defects linked to ZIKV infections. The rapid emergence of ZIKV has prompted many questions relating to: why there is an increase in disease severity, what is the immunological response to ZIKV infection and are there viral and/or immune mediated pathologies linked to the increase in neurological manifestations and birth defects. There is now a rush to understand the central nervous system (CNS) related disease associated with ZIKV as well as the need to rapidly test the efficacy of the antivirals and vaccines against ZIKV. It is against this backdrop that we have developed methods for the rapid analysis of ZIKV titers in both the periphery and CNS using a ZIKV-specific focus forming assays (FFA).
Small animal models are important for understanding disease progression and for the early evaluation of vaccines, therapeutics, and anti-virals. We have established small animal models for the study of arbovirus disease by using various mouse strains to model human infection and protection against viral pathogens8,9,10,11,12,13,14,15,16,17,18,19,20,21,22. Using this prior experience, we began to modify techniques used for the assessment of WNV and Dengue virus, a related flavivirus for the assessment of ZIKV titer in both peripheral organs as well as the CNS21,23,24. The advantages of these methods over other assays are: 1) that they combine the ability to harvest both peripheral and CNS organs for the analysis; 2) the methods are adaptable for flow cytometry, for measurements of innate and adaptive immune responses, along with viral titers on the same animal in the same organ; 3) the harvest technique is adaptable for histological analysis; 4) the ZIKV FFA is a rapid high throughput method for viral titer analysis; and 5) these methods can be applied to the assessment of viral titers in the organs of animals infected with most pathogens25.

<table>
	<tbody>
		<tr>
			<td>1-bromo-3-chloropropane (BCP)</td>
			<td>MRC gene</td>
			<td>BP151</td>
			<td></td>
		</tr>
		<tr>
			<td>10cc syringe</td>
			<td>Thermo Fisher Scientific</td>
			<td>BD 309642</td>
			<td></td>
		</tr>
		<tr>
			<td>18G needle</td>
			<td>Thermo Fisher Scientific</td>
			<td>22-557-145</td>
			<td></td>
		</tr>
		<tr>
			<td>1cc TB syringe</td>
			<td>Thermo Fisher Scientific</td>
			<td>14-823-16H</td>
			<td></td>
		</tr>
		<tr>
			<td>20cc syringe</td>
			<td>Thermo Fisher Scientific</td>
			<td>05-561-66</td>
			<td></td>
		</tr>
		<tr>
			<td>24 tube beadmill</td>
			<td>Thermo Fisher Scientific</td>
			<td>15 340 163</td>
			<td></td>
		</tr>
		<tr>
			<td>3.2 mm stainless steel beads</td>
			<td>Thermo Fisher Scientific</td>
			<td>NC9084634</td>
			<td></td>
		</tr>
		<tr>
			<td>37C Tissue Culture incubator</td>
			<td>Nuair</td>
			<td>5800</td>
			<td></td>
		</tr>
		<tr>
			<td>4G2 antibody</td>
			<td>in house</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>96 well flat bottom plates</td>
			<td>Midsci</td>
			<td>TP92696</td>
			<td></td>
		</tr>
		<tr>
			<td>96well round bottom plates</td>
			<td>Midsci</td>
			<td>TP92697</td>
			<td></td>
		</tr>
		<tr>
			<td>Basix 1.5ml eppendorf tubes</td>
			<td>Thermo Fisher Scientific</td>
			<td>02-682-002</td>
			<td></td>
		</tr>
		<tr>
			<td>Concentrated Germicidal Bleach</td>
			<td>Staples</td>
			<td>30966CT</td>
			<td></td>
		</tr>
		<tr>
			<td>CTL S6 Analyzer</td>
			<td>CTL</td>
			<td>CTL S6 Universal Analyzer</td>
			<td></td>
		</tr>
		<tr>
			<td>curved cutting scissors</td>
			<td>Fine Science Tools</td>
			<td>14061-11</td>
			<td></td>
		</tr>
		<tr>
			<td>Dulbecco&#8217;s Modified Eagle&#8217;s Medium - high glucose With 4500 mg/L glucose</td>
			<td>MilliporeSigma</td>
			<td>D5671</td>
			<td></td>
		</tr>
		<tr>
			<td>Ethanol (molecular biology-grade)</td>
			<td>MilliporeSigma</td>
			<td>e7023</td>
			<td></td>
		</tr>
		<tr>
			<td>Fetal Bovine Serum</td>
			<td>MilliporeSigma</td>
			<td>F0926-500ML</td>
			<td></td>
		</tr>
		<tr>
			<td>Forceps</td>
			<td>Fine Science Tools</td>
			<td>11036-20</td>
			<td></td>
		</tr>
		<tr>
			<td>Glacial acetic acid</td>
			<td>MilliporeSigma</td>
			<td>537020</td>
			<td></td>
		</tr>
		<tr>
			<td>Goat anti-mouse HRP-labeled antibody</td>
			<td>MilliporeSigma</td>
			<td>8924</td>
			<td></td>
		</tr>
		<tr>
			<td>HEPES 1 M</td>
			<td>MilliporeSigma</td>
			<td>H3537-100ML</td>
			<td></td>
		</tr>
		<tr>
			<td>Isopropanol (molecular biology-grade)</td>
			<td>MilliporeSigma</td>
			<td>I9516</td>
			<td></td>
		</tr>
		<tr>
			<td>Ketamine/Xylazine cocktail</td>
			<td>Comparative Medicine</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>L-glutamine</td>
			<td>MilliporeSigma</td>
			<td>g7513</td>
			<td></td>
		</tr>
		<tr>
			<td>Magmax RNA purification kit</td>
			<td>Thermo Fisher Scientific</td>
			<td>AM1830</td>
			<td></td>
		</tr>
		<tr>
			<td>Methylcellulose</td>
			<td>MilliporeSigma</td>
			<td>M0512</td>
			<td></td>
		</tr>
		<tr>
			<td>Microcentrifuge</td>
			<td>Ependorf</td>
			<td>5424R</td>
			<td></td>
		</tr>
		<tr>
			<td>MiniCollect 0.5ml EDTA tubes</td>
			<td>Bio-one</td>
			<td>450480</td>
			<td></td>
		</tr>
		<tr>
			<td>o-ring tubes</td>
			<td>Thermo Fisher Scientific</td>
			<td>21-403-195</td>
			<td></td>
		</tr>
		<tr>
			<td>one step q RT-PCR mix</td>
			<td>Thermo Fisher Scientific</td>
			<td>4392938</td>
			<td></td>
		</tr>
		<tr>
			<td>Paraformaldehyde</td>
			<td>Thermo Fisher Scientific</td>
			<td>EMS- 15713-S</td>
			<td></td>
		</tr>
		<tr>
			<td>Phosphate Buffered Saline</td>
			<td>MilliporeSigma</td>
			<td>d8537-500ml</td>
			<td></td>
		</tr>
		<tr>
			<td>Proline multichannel pipettes</td>
			<td>Sartorius</td>
			<td>72230/72240</td>
			<td></td>
		</tr>
		<tr>
			<td>Proline single channel pipettes</td>
			<td>Sartorius</td>
			<td>728230</td>
			<td></td>
		</tr>
		<tr>
			<td>RNAse free water</td>
			<td>Thermo Fisher Scientific</td>
			<td>10-977-023</td>
			<td></td>
		</tr>
		<tr>
			<td>RNAzol BD</td>
			<td>MRC gene</td>
			<td>RB192</td>
			<td></td>
		</tr>
		<tr>
			<td>Rocking Platform</td>
			<td>Thermo Fisher Scientific</td>
			<td>11-676-333</td>
			<td></td>
		</tr>
		<tr>
			<td>RPMI 1640</td>
			<td>Fisher</td>
			<td>MT10040CV</td>
			<td></td>
		</tr>
		<tr>
			<td>Saponin</td>
			<td>MilliporeSigma</td>
			<td>s7900</td>
			<td></td>
		</tr>
		<tr>
			<td>spoon/spatula</td>
			<td>Fine Science Tools</td>
			<td>10090-17</td>
			<td></td>
		</tr>
		<tr>
			<td>straight cutting scissors</td>
			<td>Fine Science Tools</td>
			<td>14060-11</td>
			<td></td>
		</tr>
		<tr>
			<td>Triton X-100</td>
			<td>MilliporeSigma</td>
			<td>t8787</td>
			<td></td>
		</tr>
		<tr>
			<td>True Blue Substrate</td>
			<td>VWR</td>
			<td>95059-168</td>
			<td></td>
		</tr>
		<tr>
			<td>Trypsin</td>
			<td>MilliporeSigma</td>
			<td>T3924-100ML</td>
			<td></td>
		</tr>
	</tbody>
</table>

isolation and quantification of zika virus from multiple organs in a mouse

The methods being presented demonstrate laboratory procedures for the isolation of organs from Zika virus infected animals and the quantification of viral load. The purpose of the procedure is to quantify viral titers in peripheral and CNS areas of the mouse at different time points post infection or under different experimental conditions to identify virologic and immunological factors that regulate Zika virus infection. The organ isolation procedures demonstrated allow for both focus forming assay quantification and quantitative PCR assessment of viral titers. The rapid organ isolation techniques are designed for the preservation of virus titer. Viral titer quantification by focus forming assay allows for the rapid throughput assessment of Zika virus. The benefit of the focus forming assay is the assessment of infectious virus, the limitation of this assay is the potential for organ toxicity reducing the limit of detection. Viral titer assessment is combined with quantitative PCR, and using a recombinant RNA copy control viral genome copy number within the organ is assessed with low limit of detection. Overall these techniques provide an accurate rapid high throughput method for the analysis of Zika viral titers in the periphery and CNS of Zika virus infected animals and can be applied to the assessment of viral titers in the organs of animals infected with most pathogens, including Dengue virus.

To evaluate ZIKV titers using the protocol described above Ifnar1-/- mice were infected with ZIKV (PRVABC59) via subcutaneous (SC) injection to the footpad. Here, the administration of 1 x 105 FFU of ZIKV to 8-12 week old Ifnar1-/- mice SC is not lethal but the virus can replicate in both the periphery and CNS. This dose and route are used to study host pathogen immune responses and pathogenicity. Administration of 1 x 105 FFU ...

Watch this Scientific Journal Video about Isolation and Quantification of Zika Virus from Multiple Organs in a Mouse at JoVE.com

Isolation and Quantification of Zika Virus from Multiple Organs in a Mouse

The goal of the protocol is to demonstrate the techniques used to investigate viral disease by isolating and quantifying Zika virus, from multiple organs in a mouse following infection.

The methods being presented demonstrate laboratory procedures for the isolation of organs from Zika virus infected animals and the quantification of viral ...

In this video we describe a set of procedures designed to interrogate the impact of a viral infection and the resulting immunological response using a Murine model of Zika infection. This protocol is significant because it allows us to develop a mechanistic understanding of infection and immunity by identifying the extent to which a virus has spread throughout the body, transversing physical barriers and accessing tissues. These techniques allow a detailed understanding of viral pathogenesis and provides the ability to dissect the mechanism of protection provided by vaccines or therapeutics.Here we demonstrate this method using Zika virus infection of mice, but this method can be applied to a range of viral infections including other flaviviruses like Dengue virus and alphaviruses like Chikungunya virus. Harvesting the organs of the central nervous system can be challenging, so it's important for a person to plan a small experiment, and be prepared to practice the techniques beforehand. This protocol allows for the rapid dissection of viral spread within small animal models with the ability to visualize, capture, and store experimental data.It is important to visually demonstrate this method to allow the experimenter to understand how to harvest the central nervous system organs. It's also important to see the level of cell confluency and the intensity of the viral foci. To begin, use forceps to remove the pelt of the infected mouse.Decapitate the head of the mouse with scissors, followed by the removal of the arms and legs. To harvest the brain, use serrated La Grange scissors to cut the skull through the foramen magnum. Peel off the skull with forceps, and scoop out the brain with a spatula.Using strong blunted scissors, remove the bone surrounding the spine, then cut across the pelvic bone to expose the vertebral foramen at the lumbar level. Then, remove as much muscle as possible surrounding the spinal column. Carefully, place the beveled tip of the needle inside the vertebral foramen, avoiding excessive pressure to prevent the needle trespassing the vertebral body.Hold strongly to exert pressure on the vertebral body and the needle, and press the syringe plunger to expel the cord into the petri dish. Immediately transfer the spinal cord in the labeled tube, and place in the dry ice bath for further homogenization. For homogenization, add one milliliter of DMEM and homogenize the sample in a BeadBeater.After ensuring organs are homogenized, centrifuge and aliquot samples on ice and store in the minus 80 degrees Celsius until needed. On the day of the assay, remove the homogenized samples from the minus 80 degrees Celsius freezer, and allow them to thaw. With the samples on ice, dilute Zika virus tenfold into the first well of the dilution plate and use a multichannel pipette to do tenfold serial dilutions down the plate, changing tips each time.By adding 20 microliters of sample into 180 microliters of growth media, change pipette tips between each dilution. Prepare the focus forming plate by removing the media from the prepared flat bottom 96-well plate covering virocells. To prevent the monolayer from drying out, immediately add 100 microliters of the virus dilution to each well in the viroplate.Use the same set of tips to add from the lowest to the highest concentration. Rock plate side to side two to four times and incubate at 37 degrees Celsius in 5%carbon dioxide for one to two hours. Warm up 2%methylcellulose to room temperature.Then, dilute the 2%methylcellulose solution in growth media at a ratio of approximately two to one. After incubation, add 125 microliters of the methylcellulose growth media to each well of the 96-well plates. Incubate again at 37 degrees Celsius in 5%carbon dioxide for 32 to 40 hours.To fix the virocells, in a biosafety cabinet add 50 microliters of 5%paraformaldehyde over the top of the methylcellulose layer in each well of the 96-well plates. Incubate for 60 minutes at room temperature. Alternatively, cover the plates with Parafilm and place them at four degrees Celsius overnight.After that, use a pipette to remove overlay and media off cells into a disposable container inside the biosafety cabinet. Wash gently with 150 microliters of PBS per well. Remove PBS from the plates and remove the plate from the biosafety cabinet.Repeat the PBS wash twice, then add 150 microliters per well one times FFA wash buffer and leave at room temperature for five to 10 minutes to permeabilize the fixed cells. Next, use primary Zika antibody to detect infection. Prepare the primary antibody 4G2 at a concentration of one microgram per milliliter in FFA staining buffer.Flick FFA wash buffer from the plates, and add 50 microliters of the primary antibody in FFA staining buffer to each well. Then seal the plates with Parafilm, or plastic film, and incubate overnight at four degrees Celsius. Prepare the secondary go anti-mouse HRP labeled antibody at a concentration of one to 5, 000 in FFA staining buffer.After removing the antibody solution, wash cells three times with 150 microliters FFA wash buffer per well. Remove the wash buffer by flicking into the sink each time. Stain the cells with the secondary antibody in FFA staining buffer at 50 microliters per well and incubate one to two hours at room temperature.After that, wash cells three times with FFA wash buffer, again, removing the wash buffer by flicking into the sink each time. Add 50 microliters of the TrueBlue Substrate into each well. Wait two to 15 minutes until spots are fully defined with minimal background.After the spots are visible, wash gently with water using a hand to shield the monolayer from the force of the water running. Tap dry on paper towels. Shortly after, use a dissecting scope to count manually the spots in each well, or use an automated spot counter.In the ImmunoCapture software, select a dilution with easily distinguished foci between 20 to 200 per well for each sample and calculate titer in focus-forming units per millimeter using the average of duplicate wells. In this experiment, viral burden was shown in the peripheral and central nervous system tissues after Ifnar mice were given Zika virus subcutaneously. The limit of detection was between 100 to 500 FFU per gram, based upon organ.When performing the focus-forming assay, technical mistakes can result in suboptimal results. Organ toxicity, driven by high concentration of liver, altered the sensitivity of the assay. When the viral titer in the organ was lower than the toxicity, the FFA could not accurately record the viral titers.Kidney cells illustrated toxicity with high organ concentration but was overcome by the viral titer at low organ concentrations. Vigorous pipetting or washing can remove the monolayer, leading to lost data inaccurate reporting of titer results. Fibers or hairs that are present in lab bench absorbent paper, can contaminate individual wells and cause significant errors if using an automated counting program.Cell density is another issue, which can dramatically impact the success of a focus-forming assay. Cells at approximately 60%confluency at the start of the assay, compared to cells plated at 90%confluency, showed dramatic difference impacting the focus-forming assay. Planning the size and scope of the experiment so that organ harvest is completed efficiently, is the most important part of the procedure, followed by starting the focus-forming assay with high quality cells.This procedure has been used to quantify virus for multiple viral families. This protocol can also be adapted to screen for therapeutic compounds and quantify neutralizing antibody titers. These techniques are used to quantitate live virus and appropriate safety steps should be taken according to the guidelines laid out in the BMBL.

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JoVE Journal

Immunology and Infection

7.3K ビュー.  Saint Louis University. このビデオでは、ジカ感染のマウスモデルを使用して、ウイルス感染の影響と結果として生じる免疫学的応答を尋問するために設計された一連の手順について説明します。このプロトコルは、ウイルスが体内に広がった程度を特定し、物理的な障壁を横断し、組織にアクセスすることによって、感染と免疫の機械学的理解を開発することを可能にするので、重要です。?...

ビデオ: Isolation and Quantification of Zika Virus from Multiple Organs in a Mouse

The goal of the protocol is to demonstrate the techniques used to investigate viral disease by isolating and quantifying Zika virus, from multiple organs in a mouse following...

a focus-forming assay for quantifying virus titers in the organs of an infected mouse

The video demonstrates a procedure for quantifying the Zika virus in multiple mouse organs via a focus-forming assay. The process involves infecting mammalian cell monolayers with virus-infected tissue homogenates, followed by the use of methyl cellulose to prevent viral spread. Subsequently, immunostaining is employed to enable precise quantification and measurement of organ-specific...

A Focus-Forming Assay for Quantifying Virus Titers in the Organs of an Infected Mouse

virus propagation and cell-based colorimetric quantification

Virus Propagation and Cell-Based Colorimetric Quantification

The present protocol describes the propagation of Zika virus (ZIKV) in Vero African green monkey kidney cells and the quantification of ZIKV using cell-based colorimetric immunodetection methods in 24-well and 96-well (high throughput)...

evaluation of zika virus-specific t-cell responses in immunoprivileged organs of infected ifnar1-/- mice

Evaluation of Zika Virus-specific T-cell Responses in Immunoprivileged Organs of Infected Ifnar1-/- Mice

A protocol to evaluate antigen-specific T-cell responses in the immunoprivileged organs of the Ifnar1-/- murine model for the Zika virus (ZIKV) infection is described. This method is pivotal for investigating the cellular mechanisms of the protection and immunopathogenesis of ZIKV vaccines and is also valuable for their efficacy...

Evaluation of Zika Virus-specific T-cell Responses in Immunoprivileged Organs of Infected Ifnar1-/- Mice

rescue and characterization of recombinant virus from a new world zika virus infectious clone

Rescue and Characterization of Recombinant Virus from a New World Zika Virus Infectious Clone

This protocol describes the recovery of infectious Zika virus from a two-plasmid infectious cDNA...

quantification of antibody-dependent enhancement of the zika virus in primary human cells

Quantification of Antibody-dependent Enhancement of the Zika Virus in Primary Human Cells

We describe a method to evaluate the effect of pre-existing immunity against dengue virus on the Zika virus infection by using human serum, primary human cells, and infection quantification by quantitative real-time polymerase chain...

rescue of recombinant zika virus from a bacterial artificial chromosome cdna clone

Rescue of Recombinant Zika Virus from a Bacterial Artificial Chromosome cDNA Clone

The recent epidemic of Zika virus highlights the importance of establishing reverse genetic approaches to develop vaccines and/or therapeutic strategies. Here, we describe the protocol to rescue an infectious recombinant Zika virus from a full-length cDNA clone assembled in a bacterial artificial chromosome under the control of the human cytomegalovirus immediate-early...

isolation and quantification of epstein-barr virus from the p3hr1 cell line

Isolation and Quantification of Epstein-Barr Virus from the P3HR1 Cell Line

This protocol permits the isolation of Epstein-Barr virus particles from the human P3HR1 cell line upon inducing the viral lytic cycle with phorbol 12-myristate 13-acetate. DNA is subsequently extracted from the viral preparation and subjected to real-time PCR to quantify the viral particle concentration.

zika virus infectious cell culture system and the in vitro prophylactic effect of interferons

Zika Virus Infectious Cell Culture System and the In Vitro Prophylactic Effect of Interferons

Zika Virus (ZIKV), an emerging pathogen, is linked to fetal developmental abnormalities and microcephaly. The establishment of an effective infectious cell culture system is crucial for studies of ZIKV replication as well as vaccine and drug development. In this study, various virological assays pertaining to ZIKV are illustrated and...

Zika Virus Infectious Cell Culture System and the In Vitro Prophylactic Effect of Interferons

zika virus specific diagnostic epitope discovery

Zika Virus Specific Diagnostic Epitope Discovery

In this protocol, we describe a technique to discover Zika virus specific diagnostic peptides using a high-density peptide microarray. This protocol can readly be adapted for other emerging infectious...

isolation of multiple cell types from a mouse brain by mechanical homogenization

Fill the tube to a final volume of 10 milliliters with prechilled HBSS for centrifugation and resuspend the pellet in 7 milliliters of fresh HBSS with vortexing before holding the sample on ice. For debris removal, add 3 milliliters of prechilled isotonic solution to each digested or homogenized sample, and gently vortex the samples to make sure they are homogeneously...

Isolation of Multiple Cell Types from a Mouse Brain by Mechanical Homogenization

establishing mouse models for zika virus-induced neurological disorders using intracerebral injection strategies: embryonic, neonatal, and adult

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

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...

This video demonstrates the isolation of multiple types of cells from mouse brain tissue. Tissue is first mechanically sheared using a tissue grinder in a salt solution to maintain an osmotic balance. The tissue homogenate is then subjected to density gradient centrifugation to remove cellular debris. Cells are then resuspended in a solution for further...

fat body organ culture system in aedes aegypti, a vector of zika virus

Fat Body Organ Culture System in Aedes Aegypti, a Vector of Zika Virus

The fat body is the central metabolic organ in insects. We present a live organ culture system that enables the user to study the responses of isolated fat body tissue to various...

Fat Body Organ Culture System in Aedes Aegypti, a Vector of Zika Virus

stromal cell isolation from hematopoietic organs

Author Spotlight: Advancing Hematopoietic Research Using Stromal Cell Isolation for Single Cell Sequencing

Here we present protocols that enable isolation of stromal cells from murine bone, bone marrow, thymus and human thymic tissue compatible with single-cell...

Stromal Cell Isolation From Hematopoietic Organs

Change pipette tips between each dilution. Prepare the focus-forming plate by removing the media from the prepared flat-bottom 96-well plate covering Vero cells. To prevent the monolayer from drying out, immediately add 100 microliters of the virus dilution to each well in the Vero plate. Use the same set of tips to add from the lowest to the highest...

a simple flow cytometry based assay to determine in vitro antibody dependent enhancement of dengue virus using zika virus convalescent serum

A Simple Flow Cytometry Based Assay to Determine In Vitro Antibody Dependent Enhancement of Dengue Virus Using Zika Virus Convalescent Serum

We describe a simple and easy protocol for measuring antibody dependent enhancement of infection by Zika virus convalescent serum using Dengue virus Reporter Viral...

A Simple Flow Cytometry Based Assay to Determine In Vitro Antibody Dependent Enhancement of Dengue Virus Using Zika Virus Convalescent Serum

cell-based electrical impedance platform to evaluate zika virus inhibitors in real time

Cell-Based Electrical Impedance Platform to Evaluate Zika Virus Inhibitors in Real Time

Here, we demonstrate the use of cell-based electrical impedance (CEI) as a very easy and straightforward method to study Zika virus infection and replication in human cells in real time. Furthermore, the CEI assay is useful for the evaluation of antiviral...

vector competence analyses on aedes aegypti mosquitoes using zika virus

Vector Competence Analyses on Aedes aegypti Mosquitoes using Zika Virus

The presented protocol can determine the vector competence of Aedes aegypti mosquito populations for a given virus, such as Zika, in a containment...

Vector Competence Analyses on Aedes aegypti Mosquitoes using Zika Virus

high-throughput antiviral assays to screen for inhibitors of zika virus replication

High-throughput Antiviral Assays to Screen for Inhibitors of Zika Virus Replication

In this work, we describe the protocols used in replicon-based and viral enzyme-based assays to screen for inhibitors of Zika virus replication in a high-throughput screening...

Isolation of Lymphocytes from Mouse Genital Tract Mucosa

Mucosal surfaces, including in the gastrointestinal, urogenital, and respiratory tracts, provide portals of entry for pathogens, such as viruses and bacteria 1. Mucosae are also inductive sites in the host to generate immunity against pathogens, such as the Peyers patches in the intestinal tract and the nasal-associated lymphoreticular tissue in the respiratory tract. This unique feature brings mucosal immunity as a crucial player of the host defense system. Many studies have been focused on gastrointestinal and respiratory mucosal sites. However, there has been little investigation of reproductive mucosal sites. The genital tract mucosa is the primary infection site for sexually transmitted diseases (STD), including bacterial and viral infections. STDs are one of the most critical health challenges facing the world today. Centers for Disease Control and Prevention estimates that there are 19 million new infectious every year in the United States. STDs cost the U.S. health care system $17 billion every year 2, and cost individuals even more in immediate and life-long health consequences. In order to confront this challenge, a greater understanding of reproductive mucosal immunity is needed and isolating lymphocytes is an essential component of these studies. Here, we present a method to reproducibly isolate lymphocytes from murine female genital tracts for immunological studies that can be modified for adaption to other species. The method described below is based on one mouse.&#x2003;

An efficient way to isolate lymphocytes from mouse genital tract is described. This method takes advantage of enzyme digestion and Percoll gradient separation to allow efficient isolation. This technique is also adaptable to for use in other species

Mucosal surfaces, including in the gastrointestinal, urogenital, and respiratory tracts, provide portals of entry for pathogens, such as viruses and ...

Nasal Wipes for Influenza A Virus Detection and Isolation from Swine

Surveillance for influenza A viruses in swine is critical to human and animal health because influenza A virus rapidly evolves in swine populations and new strains are continually emerging. Swine are able to be infected by diverse lineages of influenza A virus making them important hosts for the emergence and maintenance of novel influenza A virus strains. Sampling pigs in diverse settings such as commercial swine farms, agricultural fairs, and live animal markets is important to provide a comprehensive view of currently circulating IAV strains. The current gold-standard ante-mortem sampling technique (i.e. collection of nasal swabs) is labor intensive because it requires physical restraint of the pigs. Nasal wipes involve rubbing a piece of fabric across the snout of the pig with minimal to no restraint of the animal. The nasal wipe procedure is simple to perform and does not require personnel with professional veterinary or animal handling training. While slightly less sensitive than nasal swabs, virus detection and isolation rates are adequate to make nasal wipes a viable alternative for sampling individual pigs when low stress sampling methods are required. The proceeding protocol outlines the steps needed to collect a viable nasal wipe from an individual pig.

The authors present a protocol to collect swine nasal wipes to detect and isolate influenza A viruses.

Surveillance for influenza A viruses in swine is critical to human and animal health because influenza A virus rapidly evolves in swine populations and ...

Neutrophil Isolation and Analysis to Determine their Role in Lymphoma Cell Sensitivity to Therapeutic Agents

Neutrophils are the most abundant (40% to 75%) type of white blood cells and among the first inflammatory cells to migrate towards the site of inflammation. They are key players in the innate immune system and play major roles in cancer biology. Neutrophils have been proposed as key mediators of malignant transformation, tumor progression, angiogenesis and in the modulation of the antitumor immunity; through their release of soluble factors or their interaction with tumor cells. To characterize the specific functions of neutrophils, a fast and reliable method is coveted for in vitro isolation of neutrophils from human blood. Here, a density gradient separation method is demonstrated to isolate neutrophils as well as mononuclear cells from the blood. The procedure consists of layering the density gradient solution such as Ficoll carefully above the diluted blood obtained from patients diagnosed with chronic lymphocytic leukemia (CLL), followed by centrifugation, isolation of mononuclear layer, separation of neutrophils from RBCsby dextran then lysis of residual erythrocytes. This method has been shown to isolate neutrophils &#8805; 90 % pure. To mimic the tumor microenvironment, 3-dimensional (3D) experiments were performed using basement membrane matrix such as Matrigel. Given the short half-life of neutrophils in vitro, 3D experiments with fresh human neutrophils cannot be performed. For this reason promyelocytic HL60 cells are differentiated along the granulocytic pathway using the differentiation inducers dimethyl sulfoxide (DMSO) and retinoic acid (RA). The aim of our experiments is to study the role of neutrophils on the sensitivity of lymphoma cells to anti-lymphoma agents. However these methods can be generalized to study the interactions of neutrophils or neutrophil-like cells with a large range of cell types in different situations.

Neutrophils are the most abundant type of white blood cells. The isolation of neutrophils from human blood by density gradient separation method and the differentiation of human promyelocytic (HL60) cells along the granulocytic pathway are described here; to test their role on sensitivity of lymphoma cells to anti-lymphoma agents.

Neutrophils are the most abundant (40% to 75%) type of white blood cells and among the first inflammatory cells to migrate towards the site of ...

Zika Virus (ZIKV) is an emerging pathogen that is linked to fetal developmental abnormalities such as microcephaly, eye defects, and impaired growth. ZIKV is an RNA virus of the Flaviviridae family. ZIKV is mainly transmitted by mosquitoes, but can also be spread by maternal to fetal vertical transmission as well as sexual contact. To date, there are no reliable treatment or vaccine options available to protect those infected by the virus. The development of a reproducible, effective Zika virus infectious cell culture system is critical for studying the molecular mechanisms of ZIKV replication as well as drug and vaccine development. In this regard, a protocol describing a mammalian cell-based in vitro Zika virus culture system for viral production and growth analysis is reported here. Details on the formation of plaques by Zika virus on a cell monolayer and plaque assay for measuring viral titer are presented. Viral genome replication kinetics and double-stranded RNA genome replicatory intermediates are determined. This culture platform was utilized to screen against a library of a small set of cytokines resulting in the identification of interferon-&#945; (IFN-&#945;), IFN-&#946; and IFN-&#947; as potent inhibitors of Zika viral growth. In summary, an in vitro infectious Zika viral culture system and various virological assays are demonstrated in this study, which has the potential to greatly benefit the research community in elucidating further the mechanisms of viral pathogenesis and the evolution of viral virulence. Antiviral IFN-alpha can further be evaluated as a prophylactic, post-exposure prophylactic, and treatment option for Zika virus infections in high-risk populations, including infected pregnant women.

Zika Virus (ZIKV), an emerging pathogen, is linked to fetal developmental abnormalities and microcephaly. The establishment of an effective infectious cell culture system is crucial for studies of ZIKV replication as well as vaccine and drug development. In this study, various virological assays pertaining to ZIKV are illustrated and discussed.

Zika Virus (ZIKV) is an emerging pathogen that is linked to fetal developmental abnormalities such as microcephaly, eye defects, and impaired growth. ZIKV ...

Infectious cDNA clones allow for genetic manipulation of a virus, thus facilitating work on vaccines, pathogenesis, replication, transmission and viral evolution. Here we describe the construction of an infectious clone for Zika virus (ZIKV), which is currently causing an explosive outbreak in the Americas. To prevent toxicity to bacteria that is commonly observed with flavivirus-derived plasmids, we generated a two-plasmid system which separates the genome at the NS1 gene and is more stable than full-length constructs that could not be successfully recovered without mutations. After digestion and ligation to join the two fragments, full-length viral RNA can be generated by in vitro transcription with T7 RNA polymerase. Following electroporation of transcribed RNA into cells, virus was recovered that exhibited similar in vitro growth kinetics and in vivo virulence and infection phenotypes in mice and mosquitoes, respectively.

This protocol describes the recovery of infectious Zika virus from a two-plasmid infectious cDNA clone.

Infectious cDNA clones allow for genetic manipulation of a virus, thus facilitating work on vaccines, pathogenesis, replication, transmission and viral ...

High-density peptide microarrays allow screening of more than six thousand peptides on a single standard microscopy slide. This method can be applied for drug discovery, therapeutic target identification, and developing of diagnostics. Here, we present a protocol to discover specific Zika virus (ZIKV) diagnostic peptides using a high-density peptide microarray. A human serum sample validated for ZIKV infection was incubated with a high-density peptide microarray containing the entire ZIKV protein translated into 3,423 unique 15 linear amino acid (aa) residues with a 14-aa residue overlap printed in duplicate. Staining with different secondary antibodies within the same array, we detected peptides that bind to Immunoglobulin M (IgM) and Immunoglobulin G (IgG) antibodies present in serum. These peptides were selected for further validation experiments. In this protocol, we describe the strategy followed to design, process, and analyze a high-density peptide microarray.

In this protocol, we describe a technique to discover Zika virus specific diagnostic peptides using a high-density peptide microarray. This protocol can readly be adapted for other emerging infectious diseases.

High-density peptide microarrays allow screening of more than six thousand peptides on a single standard microscopy slide. This method can be applied for ...

Antibody dependent enhancement of infection has been shown to play a major role in Dengue viral pathogenesis. Traditional assays that measure the capacity of antibodies or serum to enhance infection in impermissible cell lines have relied on using viral output in the media followed by plaque assays to quantify infection. More recently, these assays have examined Dengue virus (DENV) infection in the cell lines using fluorescently labeled antibodies. Both these approaches have limitations that restrict the widespread use of these techniques. Here, we describe a simple in vitro assay using Dengue virus reporter viral particles (RVPs) that express green fluorescent protein and K562 cells to examine antibody dependent enhancement (ADE) of DENV infection using serum that was obtained from rhesus macaques 16 weeks after infection with Zika virus (ZIKV). This technique is reliable, involves minimal manipulation of cells, does not involve the use of live replication competent virus, and can be performed in a high throughput format to get a quantitative readout using flow cytometry. Additionally, this assay can be easily adapted to examine antibody dependent enhancement (ADE) of other flavivirus infections such as Yellow Fever virus (YFV), Japanese Equine Encephalitis virus (JEEV), West Nile virus (WNV) etc. where RVPs are available. The ease of setting up the assay, analyzing the data, and interpreting results makes it highly amenable to most laboratory settings.

We describe a simple and easy protocol for measuring antibody dependent enhancement of infection by Zika virus convalescent serum using Dengue virus Reporter Viral Particles.

Antibody dependent enhancement of infection has been shown to play a major role in Dengue viral pathogenesis. Traditional assays that measure the capacity ...

The Zika virus (ZIKV) can induce inflammation in immunoprivileged organs (e.g., the brain and testis), leading to the Guillain-Barr&#233; syndrome and damaging the testes. During an infection with the ZIKV, immune cells have been shown to infiltrate into the tissues. However, the cellular mechanisms that define the protection and/or immunopathogenesis of these immune cells during a ZIKV infection are still largely unknown. Herein, we describe methods to evaluate the virus-specific T-cell functionality in these immunoprivileged organs of ZIKV-infected mice. These methods include a) a ZIKV infection and vaccine inoculation in Ifnar1-/- mice; b) histopathology, immunofluorescence, and immunohistochemistry assays to detect the virus infection and inflammation in the brain, testes, and spleen; c) the preparation of a tetramer of ZIKV-derived T-cell epitopes; d) the detection of ZIKV-specific T cells in the monocytes isolated from the brain, testes, and spleen. Using these approaches, it is possible to detect the antigen-specific T cells that have infiltrated into the immunoprivileged organs and to evaluate the functions of these T cells during the infection: potential immune protection via virus clearance and/or immunopathogenesis to exacerbate the inflammation. These findings may also help to clarify the contribution of T cells induced by the immunization against ZIKV.

A protocol to evaluate antigen-specific T-cell responses in the immunoprivileged organs of the Ifnar1-/- murine model for the Zika virus (ZIKV) infection is described. This method is pivotal for investigating the cellular mechanisms of the protection and immunopathogenesis of ZIKV vaccines and is also valuable for their efficacy evaluation.

The Zika virus (ZIKV) can induce inflammation in immunoprivileged organs (e.g., the brain and testis), leading to the Guillain-Barr&#233; syndrome and ...

The recent emergence of the flavivirus Zika and neurological complications, such as Guillain-Barr&#233; syndrome and microcephaly in infants, has brought serious public safety concerns. Among the risk factors, antibody-dependent enhancement (ADE) poses the most significant threat, as the recent re-emergence of the Zika virus (ZIKV) is primarily in areas where the population has been exposed and is in a state of pre-immunity to other closely related flaviviruses, especially dengue virus (DENV). Here, we describe a protocol for quantifying the effect of human serum antibodies against DENV on ZIKV infection in primary human cells or cell lines.

We describe a method to evaluate the effect of pre-existing immunity against dengue virus on the Zika virus infection by using human serum, primary human cells, and infection quantification by quantitative real-time polymerase chain reaction.

The recent emergence of the flavivirus Zika and neurological complications, such as Guillain-Barr&#233; syndrome and microcephaly in infants, has brought ...

The association of Zika virus (ZIKV) infection with neurological complications during the recent worldwide outbreak and the lack of approved vaccines and/or antivirals have underscored the urgent need to develop ZIKV reverse genetic systems to facilitate the study of ZIKV biology and the development of therapeutic and/or prophylactic approaches. However, like with other flaviviruses, the generation of ZIKV full-length infectious cDNA clones has been hampered due to the toxicity of viral sequences during its amplification in bacteria. To overcome this problem, we have developed a nontraditional approach based on the use of bacterial artificial chromosomes (BACs). Using this approach, the full-length cDNA copy of the ZIKV strain Rio Grande do Norte Natal (ZIKV-RGN) is generated from four synthetic DNA fragments and assembled into the single-copy pBeloBAC11 plasmid under the control of the human cytomegalovirus (CMV) immediate-early promoter. The assembled BAC cDNA clone is stable during propagation in bacteria, and infectious recombinant (r)ZIKV is recovered in Vero cells after transfection of the BAC cDNA clone. The protocol described here provides a powerful technique for the generation of infectious clones of flaviviruses, including ZIKV, and other positive-strand RNA viruses, particularly those with large genomes that have stability problems during bacterial&#160;propagation.

The recent epidemic of Zika virus highlights the importance of establishing reverse genetic approaches to develop vaccines and/or therapeutic strategies. Here, we describe the protocol to rescue an infectious recombinant Zika virus from a full-length cDNA clone assembled in a bacterial artificial chromosome under the control of the human cytomegalovirus immediate-early promoter.

The association of Zika virus (ZIKV) infection with neurological complications during the recent worldwide outbreak and the lack of approved vaccines ...