The authors thank all the participants involved. We acknowledge the Victorian Government's Operational Infrastructure Support Program. PVL is a NHMRC Career Development Fellowship recipient.

NOTE: All steps have to be performed in a BSL2 hood unless stated differently. Viral titration is required in advance of a PRN assay to determine the optimal RSV concentration used in the PRN assay. It is recommended to aliquot the virus stocks in a small volume that will be thawed once and used for each NAb assay. Using the same viral stock for all NAb assays performed for all samples from one study is also recommended. Make sure culture media and phosphate-buffered saline (PBS) is warmed at 37 &#176;C before adding to cell plates.
1. RSV Viral Titration
NOTE: Depending on the number of virus stocks and the number of duplicates, the assay plate can be set up according to Figure 1. Each virus stock should be titrated in triplicate down the assay plate, starting at the highest viral concentration (i.e., 1:10). Serial titrations can be typically 1:10. A549 cell culture and maintenance as well as RSV culture procedure are done using standard procedures and are not included in this protocol.
<ol>
	<li>Seeding plates (Day 1) 
	<ol>
		<li>Resuspend A549 cells in Dulbecco&#8217;s Modified Eagles medium (DMEM) + 10% fetal calf serum (FCS) + 1000 IU penicillin/streptomycin (pen/strep) at 4 x 105/mL. Seed 96-well flat-bottom sterile plates with 100 &#956;L/well containing 4 x 104 A459 cells.</li>
		<li>Incubate plates overnight at 37 &#176;C, 5% CO2 (cells will be in the log-phase growth). 
		NOTE: Use new A549 cell vial after 23 passages. It is recommended to not start the experiments when a new cell vial is still at the first three passages.</li>
	</ol>
	</li>
	<li>Virus infection (Day 2) 
	<ol>
		<li>Preparation of virus serial dilution
		<ol>
			<li>Rapidly thaw a single frozen vial of RSV in a 37 &#176;C water bath until almost completely thawed and place immediately on ice. Prepare 3 replicates for each RSV virus stock to be assayed, use an initial virus stock dilution of 1:10 with 100 &#956;L of diluted virus/well and reserve at least one column for negative control. 
			NOTE: Figure 1 shows negative control in triplicates.</li>
			<li>Add 100 &#956;L of each diluted virus at 1:10 in triplicate of row A of a 96-well U-bottom sterile plate. Add 90 &#956;L/well of DMEM + 1000 IU pen/strep without FCS to rows B to H.</li>
			<li>Perform serial 1:10 dilutions down the plate by transferring 10 &#956;L from row A to row B. Mix solution by pipetting content up and down 5 times and continue the ten-fold dilutions until row H. Discard the final 10 &#956;L so that the final volume in each well is 90 &#956;L. 
			NOTE: It is important to use new tips for each dilution.</li>
		</ol>
		</li>
		<li>Virus inoculation to A549 cells
		<ol>
			<li>Retrieve A549 cell plate(s) prepared on the previous day. Ensure that A549 cell monolayers in the 96-well plates are ~80% confluent. Discard media by gently inverting plate and lightly blotting on sterile absorbent paper towel.</li>
			<li>Wash all wells with 100 &#956;L of PBS twice, discard excess PBS by gently inverting plate and lightly blotting on sterile absorbent paper towel after each wash. Do not allow plates to dry.</li>
			<li>Transfer the virus dilutions from the viral titration plate (Figure 1) to corresponding wells on the A549 cell plate. Incubate the plate for 1 h at 37 &#176;C, 5% CO2. After 1 h incubation, decant supernatants using a pipette (to avoid cross contamination). Take out 90 &#956;L/well.</li>
			<li>Add 100 &#956;L of 1x medium 199 (M199, see Table of Materials) + 1.5% carboxymethylcellulose sodium salt (CMC) low viscosity + 2% FCS containing pen/strep to each well. 
			NOTE: 2x M199 + 4% FCS + 2% pen/strep and 3% CMC solutions need to be prepared in advance and stored at 4 &#176;C for future use. Make sure the solution is warmed at 37 &#176;C before adding to plates.
			<ol>
				<li>Prepare 2x M199 solution: 1 sachet/500 mL distilled water + 20 mL FCS + 10 mL pen/strep (to make up 2x MI99). Filter the solution using a 0.22 &#956;m filter unit.</li>
				<li>For preparation of 3% CMC, add 15 g of CMC slowly into 500 mL of distilled water. Dissolve the CMC in water by using metallic stirrer heater at 50 &#176;C, which takes about 1 h of preparation. Mix well to make 3% CMC and autoclave the solution. 
				NOTE: The CMC solid must be added to the water in order to be dissolved; adding water to the dry solid produces a &#8220;clump&#8221; of solid that is very difficult to dissolve.</li>
				<li>Prepare 1x M199 + 1.5% CMC low viscosity + 2% FCS containing pen/strep by mixing 1:1 the 2x M199 and 3% CMC prepared in step 1.2.2.4.2.</li>
			</ol>
			</li>
			<li>Incubate plate for 3 days at 37 &#176;C, 5% CO2.</li>
		</ol>
		</li>
	</ol>
	</li>
	<li>Developing assay plate and analysis (Day 5)
	<ol>
		<li>Fixation and developing assay plate
		<ol>
			<li>Discard M199 + CMC + 2% FCS containing pen/strep by gently inverting the plate. Add slowly (in order to avoid disturb the cell layer) 200 &#956;L of fixation buffer (80% acetone, 20% PBS, stored at -20 &#176;C) to fix cells. Incubate at -20 &#176;C for 20 min.</li>
			<li>Discard the fixation buffer and gently blot on absorbent paper towel. Leave plate face down to dry for 10 min. 
			NOTE: From this step onwards, assay can be performed outside the BSL2 hood.</li>
			<li>Prepare 5% milk diluent blocking solution in filtered PBS containing 0.05% polysorbate 20 (PBS-polysorbate, see Table of Materials). For one plate, calculate the volume needed for blocking based on 200 /well and 110 wells: 200/well x 110 wells = 22 mL (1.1 mL concentrated milk diluent in 20.9 mL filtered PBS-polysorbate). At this stage, also make up sufficient blocking solution for primary and secondary antibodies. For one plate, calculate the volume needed for each antibody solution based on 50 /well and 110 wells: 50 /well x 110 wells = 5.5 mL. Therefore, the total volume of milk diluent blocking solution required for a single plate assay is 33 mL.</li>
			<li>Add 200 /well of blocking solution. Incubate plate at room temperature (RT) for 30 min. Discard the solution by gently inverting the plate and blot on absorbent paper towel.</li>
			<li>Prepare 1:500 Goat X RSV antibody (mAb &#8211; primary antibody) diluted in blocking solution. Add 50 /well of the mAb solution and incubate at 37 &#176;C for 1 h. Wash plate 3 times with filtered PBS-polysorbate.</li>
			<li>Prepare 1:5,000 Alexa-Fluor donkey anti-goat IgG (secondary antibody) diluted in blocking solution. Add 50 /well of the secondary antibody solution and incubate at 37 &#176;C for 1 h. Wash plate 5 times with filtered PBS-polysorbate.</li>
			<li>Read plate on an automated spots reader using the fluorescein isothiocyanate (FITC) channel and count settings as shown in Figure 2. Wrap plate in foil and store at 4 &#176;C. Calibrate the instrument using an unused 96-well culture plate and inputting count settings before assay. 
			NOTE: Re-scanning within a few days is possible if required. The calibration and count setting can be saved and used for the future scanning if the assay uses the same type of plate used for the calibration.</li>
			<li>Check the images of wells for artefact plaques or disrupted cell monolayers (Figure 3). Exclude wells with disrupted cell monolayers. 
			NOTE: Depending on the size of the artefact plaques, manual counts may need to be performed for those wells or those wells may need to be discarded from data analysis. Criteria for a valid result include no disrupted cell monolayer or artefact plaques detected in more than one replicate well and no PFU detected in negative wells (wells without added virus).</li>
		</ol>
		</li>
		<li>Determine viral concentrations 
		<ol>
			<li>Choose the last two dilutions where spots can be counted clearly. Calculate the average number of spots from replicate wells at the same dilution. Calculate the viral titer (PFU per mL) of the stock sample using the formula below: 
			PFU/mL = Average number of plaques/(Dilution factor &#215; Volume of diluted virus added to the well) 
			NOTE: The virus concentration determined for each RSV stock can now be used in the PRN assay (step 2).</li>
		</ol>
		</li>
	</ol>
	</li>
</ol>
2. RSV Neutralization Assay
<ol>
	<li>Seeding plates (Day 1)
	<ol>
		<li>Resuspend A549 cells in DMEM + 10% FCS + 1000 IU pen/strep at 4 x 105/mL. Seed 96-well flat-bottom sterile plates with 100 &#956;L/well containing 4 x 104 A459 cells and incubate plates overnight at 37 &#176;C, 5% CO2 (cells will be in the log-phase growth). 
		NOTE: Use new A549 cell vial after 23 passages. It is not recommended to use A549 cells before passage number 3.</li>
	</ol>
	</li>
	<li>Virus and serum preparation (Day 2) 
	NOTE: Depending on the sample type, there are required steps for pre-processing samples before the NAb assay. It is recommended to use the RSV international standard sera that are now available upon request from the National Institute for Biological Standards and Controls (NIBSC).
	<ol>
		<li>Preparation of serum dilution
		<ol>
			<li>Thaw the human RSV reference antiserum (reference serum, REF) and serum test samples at RT. Heat-inactivate serum samples and reference antiserum in a water bath at 56 &#176;C for 30 min prior to use. Prepare dilutions as per the plate template (Figure 4).</li>
			<li>Prepare 1:100 dilution of the REF. Prepare a minimum of 110 &#956;L of REF diluted in DMEM + pen/strep without FCS per assay plate (e.g., 1.5 &#956;L of REF in a total volume of 150 &#956;L). Add 110 &#956;L of 1:100 diluted REF in well A12 of a 96-well U-bottom sterile plate.</li>
			<li>Add 55 &#956;L of DMEM + pen/strep without FCS to wells B12 to H12 in column 12. Perform serial 1:2 dilutions down the plate by transferring 55 &#956;L from row A to row B, mixing solution by pipetting content up and down 5 times and continuing until row H. Discard the final 55 &#956;L of media so that the final volume in each well is 55 &#956;L. Use new tips for each dilution.</li>
			<li>Prepare 1:100 dilution of serum test samples. As all serum samples are assayed in triplicate, prepare a minimum volume of 110 &#956;L/well x 3 = 330 &#956;L per serum test sample.</li>
			<li>Add 110 &#956;L of each diluted serum test sample (1:100; S1 = serum 1, S2 = serum 2, etc.) to corresponding wells A1 to A9 and also E1 to E9 of the 96-well sterile plate according to Figure 4.</li>
			<li>Add 55 &#956;L of DMEM + pen/strep without FCS to all wells labelled X. Perform serial 1:2 dilutions as per step 2.2.1.3 until row D (for samples 1, 2, and 3). Discard the final 55 &#956;L of media so that the final volume in each well is 55 &#956;L. Similarly, perform the serial 1:2 dilutions for samples 4, 5, and 6 for rows E to H. 
			NOTE: It is important to use new tips for each dilution.</li>
			<li>Add 55 &#956;L of DMEM + pen/strep without FCS to wells in columns 10 and 11.</li>
		</ol>
		</li>
		<li>Preparation of virus
		<ol>
			<li>Rapidly thaw a single frozen vial of RSV in a 37 &#176;C water bath until almost completely thawed and place immediately on ice.&#8232;</li>
			<li>Dilute virus in DMEM + pen/strep without FCS based on the concentration of the RSV aliquot determined in step 1.3.2. Apply a dilution that gives approximately 200 PFU/well. Prepare a total volume of 5.5 mL (for 100 wells).</li>
		</ol>
		</li>
		<li>Preparation of virus-serum mixture
		<ol>
			<li>Add 55 of the diluted virus to all wells of columns 1-9 and wells of rows E-H of columns 10 and 11 (positive control) according to the plate template (Figure 4).</li>
			<li>Add 55 of DMEM + pen/strep without FCS to all wells of rows A-D of columns 10 and 11 (negative control). Incubate the plate for 1 h at 37 &#176;C, 5% CO2.</li>
		</ol>
		</li>
		<li>Virus inoculation to A549 cells
		<ol>
			<li>Prior to the completion of incubation period, retrieve A549 cell plate(s) prepared in step 2.1.1. Ensure that A549 cell monolayers in the 96-well plates are ~80% confluent.</li>
			<li>Discard media by gently inverting plate and lightly blotting on sterile absorbent paper towel. Wash all wells with 100 &#956;L of PBS twice, discard excess PBS by gently inverting plate and lightly blotting on sterile absorbent paper towel after each wash. Do not allow plates to dry.</li>
			<li>Transfer 100 /well of the virus-serum mixture to the corresponding wells on the A549 cell plate following the plate template Incubate the plate for 1 h at 37 &#176;C, 5% CO2.</li>
			<li>After 1 h, using a pipette, take out 90 /well and add 100 of prewarmed 1x M199 + 1.5% CMC + 2% FCS + pen/strep. Incubate plate for 3 days at 37 &#176;C, 5% CO2. 
			NOTE: Make sure the solution is warmed at 37 &#176;C before adding to plates.</li>
		</ol>
		</li>
	</ol>
	</li>
	<li>Developing assay plate and analysis (Day 5) 
	<ol>
		<li>Develop fixation and assay plate following steps 1.3.1.1 to 1.3.1.8.</li>
		<li>Determine the 50% neutralization titer &#8232;
		<ol>
			<li>Determine the 50% neutralization titer by calculating the proportional distance between the reciprocal serum dilutions above and below 50% of the &#8216;no serum&#8217; control wells (positive virus control - column 10, rows E-H).</li>
			<li>Count the number of PFU (i.e., plaques) arising from individual viral infections in serum wells and no serum control wells. Calculate the mean number of PFU of the no serum control wells and determine the 50% value.</li>
			<li>Identify serum dilutions with counts which are immediately above and below the 50% value of the no serum control wells.Using a semi-log graph or spreadsheet template, plot the number of PFU on the x-axis (linear scale) and the reciprocal serum dilution on the y-axis (log10 scale). Draw a line between the two points and read the 50% neutralization titers of the test serum samples from this line. 
			NOTE: The RSV PRN assay worksheet (Supplementary Worksheet) is used to determine the 50% neutralization titer.</li>
		</ol>
		</li>
	</ol>
	</li>
</ol>

<ol>
	<li>Shi, 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=Global,+regional,+and+national+disease+burden+estimates+of+acute+lower+respiratory+infections+due+to+respiratory+syncytial+virus+in+young+children+in+2015:+a+systematic+review+and+modelling+study.">Global, regional, and national disease burden estimates of acute lower respiratory infections due to respiratory syncytial virus in young children in 2015: a systematic review and modelling study.</a> Lancet. 390 (10098), 946-958 (2017).</li><li>Modjarrad, 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=WHO+consultation+on+Respiratory+Syncytial+Virus+Vaccine+Development+Report+from+a+World+Health+Organization+Meeting+held+on+23-24+March+2015.">WHO consultation on Respiratory Syncytial Virus Vaccine Development Report from a World Health Organization Meeting held on 23-24 March 2015.</a> Vaccine. 34 (2), 190-197 (2016).</li><li>Giersing, B. K., Karron, R. A., Vekemans, J., Kaslow, D. C., Moorthy, V. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Meeting+report:+WHO+consultation+on+Respiratory+Syncytial+Virus+(RSV)+vaccine+development,+Geneva,+25-26+April+2016.">Meeting report: WHO consultation on Respiratory Syncytial Virus (RSV) vaccine development, Geneva, 25-26 April 2016.</a> Vaccine. , (2017).</li><li>Mazur, N. 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=The+respiratory+syncytial+virus+vaccine+landscape:+lessons+from+the+graveyard+and+promising+candidates.">The respiratory syncytial virus vaccine landscape: lessons from the graveyard and promising candidates.</a> Lancet Infect Diseases. 18 (10), e295-e311 (2018).</li><li>Hosken, N., 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+multi-laboratory+study+of+diverse+RSV+neutralization+assays+indicates+feasibility+for+harmonization+with+an+international+standard.">A multi-laboratory study of diverse RSV neutralization assays indicates feasibility for harmonization with an international standard.</a> Vaccine. 35 (23), 3082-3088 (2017).</li><li>Zielinska, E., 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=Development+of+an+improved+microneutralization+assay+for+respiratory+syncytial+virus+by+automated+plaque+counting+using+imaging+analysis.">Development of an improved microneutralization assay for respiratory syncytial virus by automated plaque counting using imaging analysis.</a> Virology Journal. 2, 84 (2005).</li><li>van Remmerden, 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=An+improved+respiratory+syncytial+virus+neutralization+assay+based+on+the+detection+of+green+fluorescent+protein+expression+and+automated+plaque+counting.">An improved respiratory syncytial virus neutralization assay based on the detection of green fluorescent protein expression and automated plaque counting.</a> Virology Journal. 9, 253 (2012).</li><li>Varada, 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=A+neutralization+assay+for+respiratory+syncytial+virus+using+a+quantitative+PCR-based+endpoint+assessment.">A neutralization assay for respiratory syncytial virus using a quantitative PCR-based endpoint assessment.</a> Virology Journal. 10, 195 (2013).</li><li>Tripp, R. A., Jorquera, P. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Human respiratory syncytial virus: methods and protocols. , (2016).</li><li>Suara, R. O., 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=Prevalence+of+neutralizing+antibody+to+respiratory+syncytial+virus+in+sera+from+mothers+and+newborns+residing+in+the+Gambia+and+in+The+United+States.">Prevalence of neutralizing antibody to respiratory syncytial virus in sera from mothers and newborns residing in the Gambia and in The United States.</a> Clinical and Diagnostic Laboratory Immunology. 3 (4), 477-479 (1996).</li><li>Wang, J. W., 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=Measurement+of+neutralizing+serum+antibodies+of+patients+vaccinated+with+human+papillomavirus+L1+or+L2-based+immunogens+using+furin-cleaved+HPV+Pseudovirions.">Measurement of neutralizing serum antibodies of patients vaccinated with human papillomavirus L1 or L2-based immunogens using furin-cleaved HPV Pseudovirions.</a> PLoS One. 9 (7), e101576 (2014).</li><li>Magnus, C., Reh, L., Trkola, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=HIV-1+resistance+to+neutralizing+antibodies:+Determination+of+antibody+concentrations+leading+to+escape+mutant+evolution.">HIV-1 resistance to neutralizing antibodies: Determination of antibody concentrations leading to escape mutant evolution.</a> Virus Research. 218, 57-70 (2016).</li></ol>

The authors have nothing to disclose.

We have developed and optimized a simple and efficient RSV micro-neutralization assay that can be readily adapted in most laboratories. This assay is able to measure viral infection ability as well as measuring the inhibition of viral infection by NAb at the cellular level using computerized image scanning. The use of an imaging-based platform and specific antibody-based systems has increased the specificity and sensitivity of spot detection compared to traditional plaque detection methods6,<...

Respiratory syncytial virus (RSV) is the leading cause of lower respiratory tract infections in the pediatric population worldwide1. Despite its high burden, there is still no vaccine or treatment available. Since 2013, the World Health Organization (WHO) has declared RSV vaccine development as a major research priority, with annual WHO consultation meetings2,3. The WHO has agreed on using RSV neutralizing antibody (NAb) measurement to monitor vaccine immunogenicity, as this is recognized as the major serological marker of protection4. NAbs have been shown to protect against severe RSV infection in a number of studies as well as clinical trials of the anti-RSV monoclonal antibody palivizumab, currently the only prophylactic strategy available4.
There are multiple NAb assay formats used by laboratories worldwide, including cell-based and molecular-based assays, which have made standardization efforts challenging5,6,7,8. However, the conventional plaque-reduction neutralization (PRN) assay that measures the number of reduced plaque forming units (PFU) by the presence of an RSV-specific antibody still remains the gold standard9. Here, we report an improved, simplified, and high-throughput PRN protocol that can be used on numerous cell lines, for different RSV strains and with increased assay throughput. This protocol has been tested using clinical samples from different settings as well as on samples from animal model experiments.

<table>
	<tbody>
		<tr>
			<td>Cell line</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>A549</td>
			<td>ATCC</td>
			<td>CCL-185</td>
			<td>provided by Dr Keith Chappell, University of Queensland</td>
		</tr>
		<tr>
			<td>Viral strains</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>RSV A2</td>
			<td>ATCC</td>
			<td>VR-1540</td>
			<td>lot number 60430286</td>
		</tr>
		<tr>
			<td>Reagents</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Acetone</td>
			<td>Merck</td>
			<td>1000142511</td>
			<td></td>
		</tr>
		<tr>
			<td>Alexa-Fluor donkey anti-goat IgG (stored at 4 &#176;C)</td>
			<td>Life Technologies</td>
			<td>A11055</td>
			<td></td>
		</tr>
		<tr>
			<td>CMC sodium salt powder</td>
			<td>Sigma-Aldrich</td>
			<td>C5678-500G</td>
			<td></td>
		</tr>
		<tr>
			<td>DMEM (no serum, 3.7 g/L NaHC, P/S) (stored at 4 &#176;C)</td>
			<td>Scientific Services &#8211; Tissue Culture</td>
			<td></td>
			<td>MCRI in house supply</td>
		</tr>
		<tr>
			<td>Foetal calf Serum (stored in 50ml aliquots at -20 &#176;C)</td>
			<td>Interpath</td>
			<td>SFBS-F</td>
			<td></td>
		</tr>
		<tr>
			<td>Goat X RSV antibody</td>
			<td>Merck</td>
			<td>AB1128</td>
			<td></td>
		</tr>
		<tr>
			<td>human polyclonal antiserum to respiratory syncytial virus (RSV) (stored in 45 &#181;L aliquots at -20 &#176;C)</td>
			<td>BEI Resources</td>
			<td>NR-4022</td>
			<td>Free order through BEI Resources upon registration. This serum belong to a panel of human antiserum and immune globulin to RSV (NR-32832)</td>
		</tr>
		<tr>
			<td>M199 powder</td>
			<td>Life Technologies</td>
			<td>31100035</td>
			<td></td>
		</tr>
		<tr>
			<td>Milk diluent blocking solution (stored at 4 &#176;C)</td>
			<td>Australian Biosearch</td>
			<td>50-82-01</td>
			<td></td>
		</tr>
		<tr>
			<td>Penicillin/Streptomycin (stored in 6mL aliquots at -20 &#176;C)</td>
			<td>Life Technologies</td>
			<td>15140122</td>
			<td></td>
		</tr>
		<tr>
			<td>s.d.H2O from Milli-Q dispenser</td>
			<td>Merck</td>
			<td></td>
			<td>In-house dispensation</td>
		</tr>
		<tr>
			<td>Sterile 1X PBS for culture (stored at 4&#176;C)</td>
			<td>Scientific Services &#8211; Tissue Culture</td>
			<td></td>
			<td>MCRI in house supply</td>
		</tr>
		<tr>
			<td>Tween 20 polysorbate</td>
			<td>Sigma-Aldrich</td>
			<td>9005-64-5</td>
			<td></td>
		</tr>
		<tr>
			<td>General Consumables</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Conical Falcon tubes (50 mL)</td>
			<td>Invitro Technologies</td>
			<td>FAL352070</td>
			<td></td>
		</tr>
		<tr>
			<td>Filter unit 0.22um (500 mL)</td>
			<td>Thermo Fisher</td>
			<td>NAL5660020</td>
			<td></td>
		</tr>
		<tr>
			<td>Sterile Eppendorf tubes (1.5 mL)</td>
			<td>Australia PL</td>
			<td>AM12400</td>
			<td></td>
		</tr>
		<tr>
			<td>Sterile flat-bottom plates (96-well with lid)</td>
			<td>Interpath</td>
			<td>655180</td>
			<td></td>
		</tr>
		<tr>
			<td>Sterile U-bottom plates (96-well with lid)</td>
			<td>Interpath</td>
			<td>650180</td>
			<td></td>
		</tr>
		<tr>
			<td>5ml serological pipette</td>
			<td>Sigma-Aldrich</td>
			<td>CLS4487-200EA</td>
			<td></td>
		</tr>
		<tr>
			<td>10 mL serological pipette</td>
			<td>Interpath</td>
			<td>607180</td>
			<td></td>
		</tr>
		<tr>
			<td>25 mL serological pipette</td>
			<td>Sigma-Aldrich</td>
			<td>CLS4251-200EA</td>
			<td></td>
		</tr>
		<tr>
			<td>Tip Pipette 1-200 &#181;L Clear Maxymum Recovery Racked Pre-sterilized 10RACKS x 96TIPS PKG960</td>
			<td>Fisher Biotec</td>
			<td>TF-200-L-R-S</td>
			<td></td>
		</tr>
		<tr>
			<td>Tip Pipette 5-20 &#181;L Clear Maxymum Recovery Racked Pre-sterilized 10RACKS x 96TIPS PKG960</td>
			<td>Fisher Biotec</td>
			<td>TF-20-L-R-S</td>
			<td></td>
		</tr>
		<tr>
			<td>Tip Pipette 100-1000 &#181;LClear Maxymum Recovery Racked Pre-sterilized 10RACKS x 100TIPS PKG1000</td>
			<td>Fisher Biotec</td>
			<td>TF-1000-L-R-S</td>
			<td></td>
		</tr>
		<tr>
			<td>Tip Pipette 1-10 &#181;L Clear Maxymum Recovery Racked Pre-sterilized 10RACKS x 100TIPS PKG1001</td>
			<td>Fisher Biotec</td>
			<td>TXLF-10-L-R-S</td>
			<td></td>
		</tr>
		<tr>
			<td>Equipments and softwares</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>ELISpot reader system</td>
			<td>AID iSpot, Autoimmun Diagnostika GmbH, Strasburg, Germany</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>AID ELISpot software version 5.0</td>
			<td>AID iSpot, Autoimmun Diagnostika GmbH, Strasburg, Germany</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Microsoft Excel 2007</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
	</tbody>
</table>

an improved and high throughput respiratory syncytial virus (rsv) micro-neutralization assay

Respiratory syncytial virus-specific neutralizing antibodies (RSV NAbs) are an important marker of protection against RSV. A number of different assay formats are currently in use worldwide so there is a need for an accurate and high-throughput method for measuring RSV NAbs. We describe here an imaging-based micro-neutralization assay that has been tested on RSV subgroup A and can also be adapted for RSV subgroup B and different sample types. This method is highly reproducible, with inter-assay variations for the reference antiserum being less than 10%. We believe this assay can be readily established in many laboratories worldwide at relatively low cost. Development of an improved, high-throughput assay that measures RSV NAbs represents a significant step forward for the standardization of this method internationally as well as being critical for the evaluation of novel RSV vaccine candidates in the future.

The titration of a virus stock was performed from 1:10 to 1:108 dilution to determine the virus stock concentration prior to the PRN assay (representative results shown in Figure 5). From Figure 5, PFU can be counted reliably at dilutions of 1:104 and 1:105. The average number of PFU from triplicate wells at the same dilution was calculated. Since the average number of spots at 1:105 di...

Watch this Scientific Journal Video about An Improved and High Throughput Respiratory Syncytial Virus RSV Micro-neutralization Assay at JoVE.com

An Improved and High Throughput Respiratory Syncytial Virus RSV Micro-neutralization Assay

This study describes a high throughput, imaging-based micro-neutralization assay to determine the titer of neutralizing antibodies specific for respiratory syncytial virus (RSV). This assay format has been tested on different sample types.

An Improved and High Throughput Respiratory Syncytial Virus (RSV) Micro-neutralization Assay

Respiratory syncytial virus-specific neutralizing antibodies (RSV NAbs) are an important marker of protection against RSV. A number of different assay ...

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10.6K Views.  Murdoch Children's Research Institute. This study describes a high throughput, imaging-based micro-neutralization assay to determine the titer of neutralizing antibodies specific for respiratory syncytial virus (RSV). This assay format has been tested on different sample types.

Video: An Improved and High Throughput Respiratory Syncytial Virus RSV Micro-neutralization Assay

Mouse Eye Enucleation for Remote High-throughput Phenotyping

The mouse eye is an important genetic model for the translational study of human ophthalmic disease. Blinding diseases in humans, such as macular degeneration, photoreceptor degeneration, cataract, glaucoma, retinoblastoma, and diabetic retinopathy have been recapitulated in transgenic mice.1-5 Most transgenic and knockout mice have been generated by laboratories to study non-ophthalmic diseases, but genetic conservation between organ systems suggests that many of the same genes may also play a role in ocular development and disease. Hence, these mice represent an important resource for discovering new genotype-phenotype correlations in the eye. Because these mice are scattered across the globe, it is difficult to acquire, maintain, and phenotype them in an efficient, cost-effective manner. Thus, most high-throughput ophthalmic phenotyping screens are restricted to a few locations that require on-site, ophthalmic expertise to examine eyes in live mice. 6-9 An alternative approach developed by our laboratory is a method for remote tissue-acquisition that can be used in large or small-scale surveys of transgenic mouse eyes. Standardized procedures for video-based surgical skill transfer, tissue fixation, and shipping allow any lab to collect whole eyes from mutant animals and send them for molecular and morphological phenotyping. In this video article, we present techniques to enucleate and transfer both unfixed and perfusion fixed mouse eyes for remote phenotyping analyses.

The dissection technique illustrates enucleation of the mouse eye for tissue fixation to perform phenotyping in high-throughput screens.

The mouse eye is an important genetic model for the translational study of human ophthalmic disease. Blinding diseases in humans, such as macular ...

High Throughput Sequential ELISA for Validation of Biomarkers of Acute Graft-Versus-Host Disease

Unbiased discovery proteomics strategies have the potential to identify large numbers of novel biomarkers that can improve diagnostic and prognostic testing in a clinical setting and may help guide therapeutic interventions. When large numbers of candidate proteins are identified, it may be difficult to validate candidate biomarkers in a timely and efficient fashion from patient plasma samples that are event-driven, of finite volume and irreplaceable, such as at the onset of acute graft-versus-host disease (GVHD), a potentially life-threatening complication of allogeneic hematopoietic stem cell transplantation (HSCT).
Here we describe the process of performing commercially available ELISAs for six validated GVHD proteins: IL-2R&alpha;5, TNFR16, HGF7, IL-88, elafin2, and REG3&alpha;3 (also known as PAP1) in a sequential fashion to minimize freeze-thaw cycles, thawed plasma time and plasma usage. For this procedure we perform the ELISAs in sequential order as determined by sample dilution factor as established in our laboratory using manufacturer ELISA kits and protocols with minor adjustments to facilitate optimal sequential ELISA performance. The resulting plasma biomarker concentrations can then be compiled and analyzed for significant findings within a patient cohort. While these biomarkers are currently for research purposes only, their incorporation into clinical care is currently being investigated in clinical trials.
This technique can be applied to perform ELISAs for multiple proteins/cytokines of interest on the same sample(s) provided the samples do not need to be mixed with other reagents. If ELISA kits do not come with pre-coated plates, 96-well half-well plates or 384-well plates can be used to further minimize use of samples/reagents.

High throughput validation of multiple candidate biomarkers can be performed by sequential ELISA in order to minimize freeze/thaw cycles and use of precious plasma samples. Here, we demonstrate how to sequentially perform ELISAs for six different validated plasma biomarkers1-3 of graft-versus-host disease (GVHD)4 on the same plasma sample.

Unbiased discovery proteomics strategies have  the potential to identify large numbers of novel biomarkers that can improve  diagnostic and prognostic ...

An Organotypic High Throughput System for Characterization of Drug Sensitivity of Primary Multiple Myeloma Cells

In this work we describe a novel approach that combines ex vivo drug sensitivity assays and digital image analysis to estimate chemosensitivity and heterogeneity of patient-derived multiple myeloma (MM) cells. This approach consists in seeding primary MM cells freshly extracted from bone marrow aspirates into microfluidic chambers implemented in multi-well plates, each consisting of a reconstruction of the bone marrow microenvironment, including extracellular matrix (collagen or basement membrane matrix) and stroma (patient-derived mesenchymal stem cells) or human-derived endothelial cells (HUVECs). The chambers are drugged with different agents and concentrations, and are imaged sequentially for 96 hr through bright field microscopy, in a motorized microscope equipped with a digital camera. Digital image analysis software detects live and dead cells from presence or absence of membrane motion, and generates curves of change in viability as a function of drug concentration and exposure time. We use a computational model to determine the parameters of chemosensitivity of the tumor population to each drug, as well as the number of sub-populations present as a measure of tumor heterogeneity. These patient-tailored models can then be used to simulate therapeutic regimens and estimate clinical response.

We describe a high-throughput drug sensitivity assay for primary multiple myeloma cells. It consists of a reconstruction of the bone marrow microenvironment (including extracellular matrix and stroma) in multi-well plates, and a non-invasive method for longitudinal quantification of cell viability.

In this work we describe a novel approach that combines ex vivo drug sensitivity assays and digital image analysis to estimate chemosensitivity and ...

An Improved Method for Rapid Intubation of the Trachea in Mice

Despite some anatomical and physiological differences, mouse models continue to be an essential tool for studying human lung disease. Bleomycin toxicity is a commonly used model to study both acute lung injury and fibrosis, and multiple methods have been developed for administering bleomycin (and other toxic agents) into the lungs. However, many of these approaches, such as transtracheal instillation, have inherent drawbacks, including the need for strong anesthetics and survival surgery. This paper reports a quick, reproducible method of intratracheal intubation that involves mild inhaled anesthesia, visualization of the trachea, and the use of a surrogate spirometer to confirm exposure. As a proof of concept, 8-12 week old C57BL/6 mice were administered either 2.0 U/kg of bleomycin or an equivalent volume of PBS, and both damage and fibrotic endpoints were measured post-exposure. This procedure allows researchers to treat a large cohort of mice in a relatively short period with little expense and minimal post-procedure care.

This article presents a rapid and simple method for administering bleomycin directly into the mouse trachea via intubation. Key advantages of this method are that it is highly reproducible, easy to master, and does not require specialized equipment or lengthy recovery times.

Despite some anatomical and physiological differences, mouse models continue to be an essential tool for studying human lung disease. Bleomycin toxicity ...

A High Throughput, Multiplexed and Targeted Proteomic CSF Assay to Quantify Neurodegenerative Biomarkers and Apolipoprotein E Isoforms Status

Many neurodegenerative diseases are&#160;still lacking effective treatments. Reliable biomarkers for identifying and classifying these diseases will be important in the development of future novel therapies. Often&#160;potential new biomarkers do not make it&#160;into the clinic&#160;due to limitations&#160;in their development and&#160;high costs.&#160;However,&#160;targeted proteomics using Multiple Reaction Monitoring Liquid Chromatography-tandem/Mass Spectrometry (MRM LC-MS/MS), specifically using triple quadrupole mass spectrometers, is one method that can be used to rapidly evaluate and validate biomarkers&#160;for clinical translation into diagnostic laboratories. Traditionally, this platform has been used extensively for measurement of small molecules&#160;in clinical laboratories, but it is the potential to analyze proteins, that makes it an attractive alternative to ELISA (Enzyme-Linked Immunosorbent Assay)-based methods. We describe here how targeted proteomics can be used to measure multiplexed markers of dementia, including the detection and quantitation of the known risk factor apolipoprotein E isoform 4 (ApoE4).
In order to make the assay suitable for translation, it is designed to be rapid, simple, highly specific and cost effective. To achieve this, every step in the development of the assay must be optimized for the individual proteins and tissues they are analyzed in. This method describes a typical workflow including various tips and tricks to developing a targeted proteomics MRM LC-MS/MS for translation.
The method development is optimized using custom synthesized versions of tryptic quantotypic peptides, which calibrate&#160;the MS for detection and then spiked into CSF to determine correct identification of the endogenous peptide in the chromatographic separation prior to analysis in the MS. To achieve absolute quantitation, stable isotope-labeled internal standard versions of the peptides with short amino acid sequence tags and containing a trypsin cleavage site, are included in the assay.

We describe a high-throughput, multiplex, and targeted proteomic cerebrospinal fluid (CSF) assay developed with potential for clinical translation. The test can quantitate potential markers and risk factors for neurodegeneration, such as the apolipoprotein E variants (E2, E3 and E4), and measure their allelic expression.

Many neurodegenerative diseases are&#160;still lacking effective treatments. Reliable biomarkers for identifying and classifying these diseases will be ...

Murine Left Anterior Descending (LAD) Coronary Artery Ligation: An Improved and Simplified Model for Myocardial Infarction

Ischemic heart disease (IHD), or acute coronary syndrome (ACS), is one of the leading causes of death in the United States. IHD is characterized by reduced blood supply to the heart, resulting in the loss of oxygen to and the ensuing necrosis of the heart muscle. The MI model has gained popularity for its use as a short-term ischemia-reperfusion model and a long-term permanent ligation model. Below, we describe a reliable method for the permanent ligation of the LAD. With mouse genetic engineering technology becoming more advanced, and with an increasing availability of quality murine surgical instruments, the mouse has become a popular model for MI surgeries. Our surgical model incorporates the use of an easily reversible anesthetic for the rapid recovery of the mouse; a minimally invasive endotracheal intubation without involving a tracheotomy; and a thoracentesis through the original thoracotomy site without creating an additional incision in the chest, as is done in some other methods, to effectively remove excess blood and air from the chest cavity. This method is comparatively less invasive than other methods, which dramatically reduces surgical and post-surgical complications and mortality and improves reproducibility.

Murine Left Anterior Descending LAD Coronary Artery Ligation: An Improved and Simplified Model for Myocardial Infarction

We provide a reliable method for left anterior descending artery (LAD) ligation in a mouse model. This method is comparatively less invasive than other methods, involving endotracheal intubation, a left-sided thoracotomy approach, and thoracentesis. This method can be used as a model for both acute and chronic myocardial infarction (MI).

Ischemic heart disease (IHD), or acute coronary syndrome (ACS), is one of the leading causes of death in the United States. IHD is characterized by ...

A Component-resolved Diagnostic Approach for a Study on Grass Pollen Allergens in Chinese Southerners with Allergic Rhinitis and/or Asthma

Sensitization to grass pollen imposes a global risk for allergic airway diseases. Although prevention relies on local investigation of the pollen allergens, data on this topic are limited in southern China. Any available data were obtained by self-report questionnaires, skin prick tests, and total or specific IgE tests using crude extracts. For many reasons, these methods are unreliable. Serum sIgE reactivity to Bermuda grass, Timothy grass, and Humulus scandens allergens in a cohort of patients from Greater Guangzhou (southern China&#39;s largest city and its outskirts) with allergic rhinitis and/or asthma were examined using a fully-automated immunoassay analyzer as a component-resolved diagnostics (CRD) tool.
For the first time, a considerably high prevalence of Bermuda grass sIgE positivity was demonstrated in Chinese southerners with allergic rhinitis and/or asthma. In these patients, a subtle prevalence of sensitization to Timothy grass and Humulus scandens was also noted, which may arise from cross-reactivity, as the latter two are not common in the region. This was also supported by the detection of allergen components.
Fully-automated immunoassay analyzers may offer satisfactory consistency between regions, laboratories, and institutions and over time. The automaticity of the instrument may enable a standardized detection that would not have been readily revealed before the advent of CRD.
This is a study that uses a CRD approach to investigate sensitization to grass pollen allergens in southern China. It adds to current evidence in the literature. Future studies are needed to validate these findings. However, although CRD is a useful tool, the findings made with the fully-automated immunoassay analyzer should not substitute for other laboratory investigations, clinical evaluations, and physician expertise.

This work describes a protocol that uses a component-resolved approach to study sensitization to grass pollen allergens in a cohort of patients from southern China with allergic rhinitis and/or asthma.

Sensitization to grass pollen imposes a global risk for allergic airway diseases. Although prevention relies on local investigation of the pollen ...

High-throughput Nitrobenzoxadiazole-labeled Cholesterol Efflux Assay

Atherosclerosis leads to cardiovascular disease (CVD). It is still unclear whether cholesterol-HDL (cHDL) concentration plays a causal role in atherosclerosis development. However, an important factor in early stages of atheroma plaque formation is cholesterol efflux capacity to HDL (the ability of HDL particles to accept cholesterol from macrophages) in order to avoid foam cell formation. This is a key step in avoiding the accumulation of cholesterol in the endothelium and a part of reverse cholesterol transport (RCT) to eliminate cholesterol through the liver. Cholesterol efflux capacity to serum or plasma in macrophage cell models is a promising tool that can be used as biomarker for atherosclerosis. Traditionally, [3H]-cholesterol has been used in cholesterol efflux assays. In this study, we aim to develop a safer and faster strategy using fluorescent labelled-cholesterol (NBD-cholesterol) in a cellular assay to trace the cholesterol uptake and efflux process in THP-1-derived macrophages. Finally, we optimize and standardize the NBD-cholesterol efflux method and develop a high-throughput analysis using 96-well plates.

Measurement of in vitro cholesterol efflux capacity to serum or plasma in macrophage cell models is a promising tool as a biomarker for atherosclerosis. In the present study, we optimize and standardize a fluorescent NBD-cholesterol efflux method and develop a high-throughput analysis using 96-well plates.

Atherosclerosis leads to cardiovascular disease (CVD). It is still unclear whether cholesterol-HDL (cHDL) concentration plays a causal role in ...

Remote Laboratory Management: Respiratory Virus Diagnostics

An uptick in recent pandemics (Ebola, Zika, MERS, influenza, etc.) underlines the need for a more 'nimble,' coordinated response that addresses a multitude of issues ranging from transportation, access, facilities, equipment, and communication to provider training. To address this need, we have developed an innovative, scalable, logistics-enhanced, mobile, laboratory facility for emergencies and epidemics in resource-constrained global settings. Utilizing a background in clinical operations as an academic medical center, we designed a rapidly-deployable, modular BSL-2 and BSL-3 facility with user-friendly software for tracking and management of drugs and supplies in remote regions during epidemics and outbreaks. Here, we present our intermodal, mobile, expandable shipping-container laboratory units. The design of the laboratory facilitates off-grid usage by minimizing power consumption and allowing alternate water sources. The unit's information communication technology (ICT) platform provides (i) user-friendly tablet-based documentation, (ii) enhanced tracking of patients and supplies, and (iii) integrated communication onsite with built-in telehealth capabilities. To ensure quality in remote environments, we have developed a checklist for a basic laboratory workflow and a protocol for respiratory viral diagnosis using reverse-transcription polymerase chain reaction (RT-PCR). As described, this innovative and comprehensive approach allows for the provision of laboratory capability in resource-limited global environments.

A rapidly-deployable, off-grid laboratory has been designed and built for remote, resource-constrained global settings. The features and critical aspects of the logistically-enhanced, expandable, multifunctional laboratory modules are explored. A checklist for a basic laboratory workflow and a protocol for a respiratory viral diagnostic test are developed and presented.

An uptick in recent pandemics (Ebola, Zika, MERS, influenza, etc.) underlines the need for a more 'nimble,' coordinated response that addresses a ...

High-Throughput Analysis of Optical Mapping Data Using ElectroMap

Optical mapping is an established technique for high spatio-temporal resolution study of cardiac electrophysiology in multi-cellular preparations. Here we present, in a step-by-step guide, the use of ElectroMap for analysis, quantification, and mapping of high-resolution voltage and calcium datasets acquired by optical mapping. ElectroMap analysis options cover a wide variety of key electrophysiological parameters, and the graphical user interface allows straightforward modification of pre-processing and parameter definitions, making ElectroMap applicable to a wide range of experimental models. We show how built-in pacing frequency detection and signal segmentation allows high-throughput analysis of entire experimental recordings, acute responses, and single beat-to-beat variability. Additionally, ElectroMap incorporates automated multi-beat averaging to improve signal quality of noisy datasets, and here we demonstrate how this feature can help elucidate electrophysiological changes that might otherwise go undetected when using single beat analysis. Custom modules are included within the software for detailed investigation of conduction, single file analysis, and alternans, as demonstrated here. This software platform can be used to enable and accelerate the processing, analysis, and mapping of complex cardiac electrophysiology.

This protocol describes the setup and use of ElectroMap, a MATLAB-based open-source software platform for analysis of cardiac optical mapping data. ElectroMap provides a versatile high-throughput tool for analysis of optical mapping voltage and calcium datasets across a wide range of cardiac experimental models.

Optical mapping is an established technique for high spatio-temporal resolution study of cardiac electrophysiology in multi-cellular preparations. Here we ...