Name: a miniaturized glycan microarray assay for assessing avidity and specificity of influenza a virus hemagglutinins
Uploaded: 2016-05-29T14:00:00
Description: Watch this Scientific Journal Video about A Miniaturized Glycan Microarray Assay for Assessing Avidity and Specificity of Influenza A Virus Hemagglutinins at JoVE.com

This work was supported in part by the Scripps Microarray Core Facility, and a contract from the Centers for Disease Control (J.C.P.). RPdV is a recipient of a Rubicon and VENI grant from the Netherlands Organization for Scientific Research (NWO). The Consortium for Functional Glycomics (http://www.functionalglycomics.org/) funded by NIGMS grant GM62116 (J.C.P.) provided several glycans used in this study. This is publication 29113 from The Scripps Research Institute.

NOTE: All steps are carried out at room temperature unless otherwise indicated.&#160;
1. Array Construction
<ol>
	<li>Glycan Preparation and Plate Setup
	<ol>
		<li>Prepare a stock of printing buffer. First make 500 ml of a 150 mM stock solution of dibasic sodium phosphate. Also make 50 ml of a 150 mM stock solution of monobasic sodium phosphate solution. In a flask, using a magnetic stir bar and pH meter, slowly titrate the dibasic sodium phosphate solution with the monobasic solution until a pH of 8.5 is reach...

<ol>
	<li>Tumpey, T. 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=A+two-amino+acid+change+in+the+hemagglutinin+of+the+1918+influenza+virus+abolishes+transmission.">A two-amino acid change in the hemagglutinin of the 1918 influenza virus abolishes transmission.</a> Science. 315 (5812), 655-659 (2007).</li><li>Xu, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functional+balance+of+the+hemagglutinin+and+neuraminidase+activities+accompanies+the+emergence+of+the+2009+H1N1+influenza+pandemic.">Functional balance of the hemagglutinin and neuraminidase activities accompanies the emergence of the 2009 H1N1 influenza pandemic.</a> J Virol. 86 (17), 9221-9232 (2012).</li><li>Bouvier, N. M., Palese, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+biology+of+influenza+viruses.">The biology of influenza viruses.</a> Vaccine. 26, D49-D53 (2008).</li><li>Freidl, G. 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=Influenza+at+the+animal-human+interface:+a+review+of+the+literature+for+virological+evidence+of+human+infection+with+swine+or+avian+influenza+viruses+other+than+A(H5N1).">Influenza at the animal-human interface: a review of the literature for virological evidence of human infection with swine or avian influenza viruses other than A(H5N1).</a> Euro Surveill. 19 (18), (2014).</li><li>Xu, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preferential+recognition+of+avian-like+receptors+in+human+influenza+A+H7N9+viruses.">Preferential recognition of avian-like receptors in human influenza A H7N9 viruses.</a> Science. 342 (6163), 1230-1235 (2013).</li><li>Paulson, J. C., de Vries, R. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=H5N1+receptor+specificity+as+a+factor+in+pandemic+risk.">H5N1 receptor specificity as a factor in pandemic risk.</a> Virus Res. 178 (1), 99-113 (2013).</li><li>Tzarum, 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=Structure+and+receptor+binding+of+the+hemagglutinin+from+a+human+H6N1+influenza+virus.">Structure and receptor binding of the hemagglutinin from a human H6N1 influenza virus.</a> Cell Host Microbe. 17 (3), 369-376 (2015).</li><li>Zhang, H., 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+Human-Infecting+H10N8+Influenza+Virus+Retains+a+Strong+Preference+for+Avian-type+Receptors.">A Human-Infecting H10N8 Influenza Virus Retains a Strong Preference for Avian-type Receptors.</a> Cell Host Microbe. 17 (3), 377-384 (2015).</li><li>Carroll, S. M., Higa, H. H., Paulson, J. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Different+cell-surface+receptor+determinants+of+antigenically+similar+influenza+virus+hemagglutinins.">Different cell-surface receptor determinants of antigenically similar influenza virus hemagglutinins.</a> J Biol Chem. 256 (16), 8357-8363 (1981).</li><li>Gambaryan, A. S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Specification+of+receptor-binding+phenotypes+of+influenza+virus+isolates+from+different+hosts+using+synthetic+sialylglycopolymers:+non-egg-adapted+human+H1+and+H3+influenza+A+and+influenza+B+viruses+share+a+common+high+binding+affinity+for+6'-sialyl(N-acetyllactosamine).">Specification of receptor-binding phenotypes of influenza virus isolates from different hosts using synthetic sialylglycopolymers: non-egg-adapted human H1 and H3 influenza A and influenza B viruses share a common high binding affinity for 6'-sialyl(N-acetyllactosamine).</a> Virology. 232 (2), 345-350 (1997).</li><li>Rogers, G. N., D'Souza, B. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Receptor+binding+properties+of+human+and+animal+H1+influenza+virus+isolates.">Receptor binding properties of human and animal H1 influenza virus isolates.</a> Virology. 173 (1), 317-322 (1989).</li><li>Rogers, G. 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=Single+amino+acid+substitutions+in+influenza+haemagglutinin+change+receptor+binding+specificity.">Single amino acid substitutions in influenza haemagglutinin change receptor binding specificity.</a> Nature. 304 (5921), 76-78 (1983).</li><li>Paulson, J. C., Rogers, G. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Resialylated+erythrocytes+for+assessment+of+the+specificity+of+sialyloligosaccharide+binding+proteins.">Resialylated erythrocytes for assessment of the specificity of sialyloligosaccharide binding proteins.</a> Methods Enzymol. 138, 162-168 (1987).</li><li>Paulson, J. C., Sadler, J. E., Hill, R. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Restoration+of+specific+myxovirus+receptors+to+asialoerythrocytes+by+incorporation+of+sialic+acid+with+pure+sialyltransferases.">Restoration of specific myxovirus receptors to asialoerythrocytes by incorporation of sialic acid with pure sialyltransferases.</a> J Biol Chem. 254 (6), 2120-2124 (1979).</li><li>Chutinimitkul, 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=In+vitro+assessment+of+attachment+pattern+and+replication+efficiency+of+H5N1+influenza+A+viruses+with+altered+receptor+specificity.">In vitro assessment of attachment pattern and replication efficiency of H5N1 influenza A viruses with altered receptor specificity.</a> J Virol. 84 (13), 6825-6833 (2010).</li><li>Glaser, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+single+amino+acid+substitution+in+1918+influenza+virus+hemagglutinin+changes+receptor+binding+specificity.">A single amino acid substitution in 1918 influenza virus hemagglutinin changes receptor binding specificity.</a> J Virol. 79 (17), 11533-11536 (2005).</li><li>Herfst, 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=Airborne+transmission+of+influenza+A/H5N1+virus+between+ferrets.">Airborne transmission of influenza A/H5N1 virus between ferrets.</a> Science. 336 (6088), 1534-1541 (2012).</li><li>Nobusawa, E., Ishihara, H., Morishita, T., Sato, K., Nakajima, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Change+in+receptor-binding+specificity+of+recent+human+influenza+A+viruses+(H3N2):+a+single+amino+acid+change+in+hemagglutinin+altered+its+recognition+of+sialyloligosaccharides.">Change in receptor-binding specificity of recent human influenza A viruses (H3N2): a single amino acid change in hemagglutinin altered its recognition of sialyloligosaccharides.</a> Virology. 278 (2), 587-596 (2000).</li><li>Gambaryan, A. S., Matrosovich, M. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+solid-phase+enzyme-linked+assay+for+influenza+virus+receptor-binding+activity.">A solid-phase enzyme-linked assay for influenza virus receptor-binding activity.</a> J Virol Methods. 39 (1-2), 111-123 (1992).</li><li>Totani, 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=Chemoenzymatic+synthesis+and+application+of+glycopolymers+containing+multivalent+sialyloligosaccharides+with+a+poly(L-glutamic+acid)+backbone+for+inhibition+of+infection+by+influenza+viruses.">Chemoenzymatic synthesis and application of glycopolymers containing multivalent sialyloligosaccharides with a poly(L-glutamic acid) backbone for inhibition of infection by influenza viruses.</a> Glycobiology. 13 (5), 315-326 (2003).</li><li>Gambaryan, A., 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=Receptor+specificity+of+influenza+viruses+from+birds+and+mammals:+new+data+on+involvement+of+the+inner+fragments+of+the+carbohydrate+chain.">Receptor specificity of influenza viruses from birds and mammals: new data on involvement of the inner fragments of the carbohydrate chain.</a> Virology. 334 (2), 276-283 (2005).</li><li>Ito, 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=Receptor+specificity+of+influenza+A+viruses+correlates+with+the+agglutination+of+erythrocytes+from+different+animal+species.">Receptor specificity of influenza A viruses correlates with the agglutination of erythrocytes from different animal species.</a> Virology. 227 (2), 493-499 (1997).</li><li>Watanabe, 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=Acquisition+of+human-type+receptor+binding+specificity+by+new+H5N1+influenza+virus+sublineages+during+their+emergence+in+birds+in+Egypt.">Acquisition of human-type receptor binding specificity by new H5N1 influenza virus sublineages during their emergence in birds in Egypt.</a> PLoS Pathog. 7 (5), e1002068 (2011).</li><li>Chandrasekaran, A., 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=Glycan+topology+determines+human+adaptation+of+avian+H5N1+virus+hemagglutinin.">Glycan topology determines human adaptation of avian H5N1 virus hemagglutinin.</a> Nat Biotechnol. 26 (1), 107-113 (2008).</li><li>Blixt, 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=Printed+covalent+glycan+array+for+ligand+profiling+of+diverse+glycan+binding+proteins.">Printed covalent glycan array for ligand profiling of diverse glycan binding proteins.</a> Proc Natl Acad Sci U S A. 101 (49), 17033-17038 (2004).</li><li>Childs, R. A., 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=Receptor-binding+specificity+of+pandemic+influenza+A+(H1N1)+2009+virus+determined+by+carbohydrate+microarray.">Receptor-binding specificity of pandemic influenza A (H1N1) 2009 virus determined by carbohydrate microarray.</a> Nat Biotechnol. 27 (9), 797-799 (2009).</li><li>Nycholat, C. 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=Recognition+of+Sialylated+Poly-N-acetyllactosamine+Chains+on+N-+and+O-Linked+Glycans+by+Human+and+Avian+Influenza+A+Virus+Hemagglutinins.">Recognition of Sialylated Poly-N-acetyllactosamine Chains on N- and O-Linked Glycans by Human and Avian Influenza A Virus Hemagglutinins.</a> Angew Chem Int Ed Engl. , (2012).</li><li>Rillahan, C. D., Paulson, J. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Glycan+microarrays+for+decoding+the+glycome.">Glycan microarrays for decoding the glycome.</a> Annu Rev Biochem. 80, 797-823 (2011).</li><li>Song, X., 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+sialylated+glycan+microarray+reveals+novel+interactions+of+modified+sialic+acids+with+proteins+and+viruses.">A sialylated glycan microarray reveals novel interactions of modified sialic acids with proteins and viruses.</a> J Biol Chem. 286 (36), 31610-31622 (2011).</li><li>Gulati, 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=Human+H3N2+Influenza+Viruses+Isolated+from+1968+To+2012+Show+Varying+Preference+for+Receptor+Substructures+with+No+Apparent+Consequences+for+Disease+or+Spread.">Human H3N2 Influenza Viruses Isolated from 1968 To 2012 Show Varying Preference for Receptor Substructures with No Apparent Consequences for Disease or Spread.</a> PLoS One. 8 (6), (2013).</li><li>Stevens, J., Blixt, O., Paulson, J. C., Wilson, I. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Glycan+microarray+technologies:+tools+to+survey+host+specificity+of+influenza+viruses.">Glycan microarray technologies: tools to survey host specificity of influenza viruses.</a> Nat Rev Microbiol. 4 (11), 857-864 (2006).</li><li>de Vries, R. P., 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=Evolution+of+the+hemagglutinin+protein+of+the+new+pandemic+H1N1+influenza+virus:+maintaining+optimal+receptor+binding+by+compensatory+substitutions.">Evolution of the hemagglutinin protein of the new pandemic H1N1 influenza virus: maintaining optimal receptor binding by compensatory substitutions.</a> J Virol. 87 (24), 13868-13877 (2013).</li><li>Yang, H., 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=Structure+and+receptor+binding+preferences+of+recombinant+human+A(H3N2)+virus+hemagglutinins.">Structure and receptor binding preferences of recombinant human A(H3N2) virus hemagglutinins.</a> Virology. 477, 18-31 (2015).</li><li>de Vries, R. P., 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+influenza+A+virus+hemagglutinin+glycosylation+state+affects+receptor-binding+specificity.">The influenza A virus hemagglutinin glycosylation state affects receptor-binding specificity.</a> Virology. 403 (1), 17-25 (2010).</li></ol>

Assessing IAV receptor specificity is an important step in analyzing pandemic potential of avian viruses. Sialic acid recognition by the virus is linked to several biological properties such as binding to and release from the cell. Knowledge of which amino-acid mutations are necessary for avian viruses to achieve &#945;2-6 binding and cross the species barrier enables pandemic preparedness. Several assays are used to determine receptor specificity; however, all have their drawbacks, including only measuring avidity and n...

Wild waterfowl are the natural reservoir for IAV, but IAV is able to cross the species barrier to poultry and mammals, including, humans. Avian IAVs recognize &#945;2-3 linked sialic acids (avian-type receptors), whereas human viruses bind &#945;2-6 linked sialic acids (human-type receptors). To be able to efficiently replicate and transmit between humans an avian IAV needs to bind to human-type receptors 1.
IAVs are divided based on serology that characterizes the antigenicity of their hemagglutinin (HA) and neuraminidase (NA) envelope glycoproteins. HA binds to sialic acids, whereas NA is the receptor-destroying enzyme at the other end of the viral lifecycle and cleaves sialic acid 2. All human infecting viruses, including H1N1, H2N2 and H3N2, have an avian origin 3. Over the last two of decades several avian to human crossovers have occurred, with H5N1, H7N7, and H7N9 being the most well-known; however, other subtypes have infected humans more sporadically (H6N1, H7N1, H7N2, H9N2, H10N7, H10N8) 4. Fortunately, it seems that none of these viruses have been able to fully adapt to human-type &#945;2-6-linked sialic acid receptors 5-8. Adaptation of avian or other zoonotic viruses to accommodate replication and transmission in human hosts could have a devastating effect on human health. Therefore, prior knowledge of how these viruses are evolving to bind human-type receptors will help world-wide surveillance of emerging influenza viruses.
Determination of receptor preference was first elucidated using erythrocytes of different species and remains a favored assay among flu researchers 9-12. The demonstration that avian viruses recognize &#945;2-3 sialic acid and human viruses &#945;2-6 linked sialic acid was originally based on an assay using hemagglutination of erythrocytes enzymatically engineered to contain each of the linkages 13,14. Although the readout is hemagglutination, a standard assay for virologists, the underlying glycan structures are not defined, only the terminal linkage. Additionally, the limited availability of the sialyltransferases, used to re-sialylate the cells, have limited the use of this assay 15-18. Subsequently, other methods of determining receptor-binding preferences were introduced using sialylated glycan structures linked to poly-acrylamide (PAA) or poly-glutamate (PGA) structures in plate-based assays 19,20. Several variations are possible in coating either the glycans or viruses to microtiter plates, each of which results in a robust, reliable and very sensitive ELISA-type assay 21-23. Alternatively, biotin-linked glycans can replace PAA/PGA and can be conjugated to streptavidin-coated plates 2,24. Although some specific sera may be required, ELISAs are standard and several glycans linked to PAA are readily commercially and non-commercially available (Consortium for Functional Glycomics (http://www.functionalglycomics.org)).
Glycan microarray technologies have emerged as an invaluable tool to determine receptor specificity, as multiple different glycans are spotted, and binding to a wide array of different structures can be assessed within a single assay 25-29. The binding of IAV to these structures provides a better understanding of the glycan structures that IAV preferentially recognizes 30-33. Glycan microarrays require small amounts of sample volume to perform a binding assay and only uses minute amounts of glycan per spot (2 nl). However, these arrays are typically used only to evaluate specificity of glycans receptors. Analysis of multiple viruses, or hemagglutinin proteins, at multiple concentration ranges can be prohibitive due to the number of slides required. Furthermore, to date, no relative avidity assay has been developed using glycan array techniques.
To combine the low sample requirement afforded by glycan microarray techniques and the sensitivity of PAA-linked glycans in ELISA-based assays, we sought to develop a multi-well glycan array that would allow for high-throughput analysis with similar or better resolution as compared to the traditional ELISA-based assay. Simultaneously, we wanted to minimize the amount of biologicals and reporter chemicals consumed. The ultimate result is a miniaturized avidity assay, specifically developed for monitoring IAV specificity and is equally applicable to assess other glycan binding proteins. Using a glass slide separated into 48 micro-wells by a Teflon mask, 6 different glycans are spotted in 6 replicates per well. The microarray platform affords the same trends in receptor binding seen in the macro ELISA format with several advantages. These include (I) printing of compound in 6 replicates, using minimal sample, versus the coating of several rows in a plate, using 100 &#181;l per well; (II) multiple different compounds analyzed simultaneously in a single well, including controls; (III) a massive decrease in incubation volume and; (IV) a larger dynamic range using a fluorescent readout. A single slide can be calculated to be equivalent to 18x 96-well plates.
With the following protocol, any lab capable of fabricating and analyzing spotted microarrays should be able to manufacture this miniaturized ELISA format.

<table>
	<tbody>
		<tr>
			<td>NEXTERION&#174; Slide H MPX-48&#160;</td>
			<td>Schott</td>
			<td>1091525</td>
			<td>Microwell slides</td>
		</tr>
		<tr>
			<td>ProScanArray Plus&#160;</td>
			<td>PerkinElmer</td>
			<td>discontinued</td>
			<td>confocal microarray scanner</td>
		</tr>
		<tr>
			<td>Innoscan 1100AL Scanner/Mapix Software</td>
			<td>Innopsys</td>
			<td>-</td>
			<td>confocal microarray scanner</td>
		</tr>
		<tr>
			<td>MicroGrid II&#160;</td>
			<td>Digilab</td>
			<td>-</td>
			<td>microaray printer</td>
		</tr>
		<tr>
			<td>SNA</td>
			<td>Vector Labs</td>
			<td>B-1305&#160;</td>
			<td>Plant Lectin</td>
		</tr>
		<tr>
			<td>ECA</td>
			<td>Vector Labs</td>
			<td>B-1145&#160;</td>
			<td>Plant Lectin</td>
		</tr>
		<tr>
			<td>Anti-Strep Antibody</td>
			<td>IBA</td>
			<td>2-1509-001&#160;</td>
			<td>Anitbody for HA binding</td>
		</tr>
		<tr>
			<td>Anti-Mouse Alexa-647</td>
			<td>Life</td>
			<td>A-21235</td>
			<td>Anitbody for HA binding</td>
		</tr>
		<tr>
			<td>Tween-20</td>
			<td>Sigma</td>
			<td>P2287&#160;</td>
			<td>detergent</td>
		</tr>
		<tr>
			<td>di-basic Sodium Phosphate</td>
			<td>Sigma</td>
			<td>255793</td>
			<td>printing buffer component</td>
		</tr>
		<tr>
			<td>mono-basic Sodium phosphate</td>
			<td>Sigma</td>
			<td>229903&#160;</td>
			<td>printing buffer component</td>
		</tr>
		<tr>
			<td>poly-l-lysine solution</td>
			<td>Sigma</td>
			<td>P8920&#160;</td>
			<td>pre-spotting slide component</td>
		</tr>
		<tr>
			<td>sodium hydroxide</td>
			<td>Sigma</td>
			<td>221465</td>
			<td>pre-spotting slide component</td>
		</tr>
		<tr>
			<td>ethanol</td>
			<td>Sigma</td>
			<td>493546</td>
			<td>pre-spotting slide component</td>
		</tr>
		<tr>
			<td>phosphate buffered saline</td>
			<td>Corning</td>
			<td>46-013-CM</td>
			<td>incubation/washing buffer</td>
		</tr>
		<tr>
			<td>SMP4B pins</td>
			<td>Telechem</td>
			<td>SMP4B</td>
			<td>printing pin</td>
		</tr>
		<tr>
			<td>Compressed Nitrogen (Grade5)</td>
			<td>Praxair</td>
			<td>UN1066</td>
			<td>general dusting/drying tool</td>
		</tr>
		<tr>
			<td>Boric Acid</td>
			<td>Sigma</td>
			<td>B6768-500G</td>
			<td>Slide blocking reagent</td>
		</tr>
		<tr>
			<td>ethanolamine</td>
			<td>Sigma</td>
			<td>E9508-500ML</td>
			<td>Slide blocking reagent</td>
		</tr>
		<tr>
			<td>Atto 488</td>
			<td>AttoTec</td>
			<td>AD 488-91</td>
			<td>Gridmarker on array</td>
		</tr>
		<tr>
			<td>PAA-LNLN</td>
			<td>Consortium for Functional Glycomics</td>
			<td>PA368</td>
			<td>Spotted glycans</td>
		</tr>
		<tr>
			<td>PAA-3SLNLN</td>
			<td>Consortium for Functional Glycomics</td>
			<td>PA362</td>
			<td>Spotted glycans</td>
		</tr>
		<tr>
			<td>PAA-6SLNLN</td>
			<td>Consortium for Functional Glycomics</td>
			<td>PA343</td>
			<td>Spotted glycans</td>
		</tr>
		<tr>
			<td>LNLN</td>
			<td>Consortium for Functional Glycomics</td>
			<td>Te98</td>
			<td>Spotted glycans</td>
		</tr>
		<tr>
			<td>3SLNLN</td>
			<td>Consortium for Functional Glycomics</td>
			<td>Te175</td>
			<td>Spotted glycans</td>
		</tr>
		<tr>
			<td>6SLNLN</td>
			<td>Consortium for Functional Glycomics</td>
			<td>Te176</td>
			<td>Spotted glycans</td>
		</tr>
		<tr>
			<td>384-well microtiter plate</td>
			<td>Matrix TechCorp</td>
			<td>4361</td>
			<td>Printing plate</td>
		</tr>
		<tr>
			<td>VWR lab marker</td>
			<td>VWR</td>
			<td>52877-150</td>
			<td>Slide Numbering</td>
		</tr>
		<tr>
			<td>Wheaton slide staining dish</td>
			<td>Sigma</td>
			<td>Z103969-1EA</td>
			<td>Blocking and Drying</td>
		</tr>
	</tbody>
</table>

a miniaturized glycan microarray assay for assessing avidity and specificity of influenza a virus hemagglutinins

Influenza A virus (IAV) hemagglutinins recognize sialic acids on the cell surface as functional receptors to gain entry into cells. Wild waterfowl are the natural reservoir for IAV, but IAV can cross the species barrier to poultry, swine, horses and humans. Avian viruses recognize sialic acid attached to a penultimate galactose by a &#945;2-3 linkage (avian-type receptors) whereas human viruses preferentially recognize sialic acid with a &#945;2-6 linkage (human-type receptors). To monitor if avian viruses are adapting to human type receptors, several methods can be used. Glycan microarrays with diverse libraries of synthetic sialosides are increasingly used to evaluate receptor specificity. However, this technique is not used for measuring avidities. Measurement of avidity is typically achieved by evaluating the binding of serially diluted hemagglutinin or virus to glycans adsorbed to conventional polypropylene 96-well plates. In this assay, glycans with &#945;2-3 or &#945;2-6 sialic acids are coupled to biotin and adsorbed to streptavidin plates, or are coupled to polyacrylamide (PAA) which directly adsorb to the plastic. We have significantly miniaturized this assay by directly printing PAA-linked sialosides and their non PAA-linked counterparts on micro-well glass slides. This set-up, with 48 arrays on a single slide, enables simultaneous assays of 6 glycan binding proteins at 8 dilutions, interrogating 6 different glycans, including two non-sialylated controls. This is equivalent to 18x 96-well plates in the traditional plate assay. The glycan array format decreases consumption of compounds and biologicals and thus greatly enhances efficiency.

Printing, Scanning &#38; Data analyses
To ensure proper printing, it is vital to have the correct alignment of the spotted grid within the teflon mask, which delineates each array on the slide. During printing, due to the nature of the teflon coating, spots cannot be seen by the naked eye on the MPX slides. Attention is paid then to the appearance of the pre-spots on the poly-L-Lysine coated slides. Directly after printing, each...

Watch this Scientific Journal Video about A Miniaturized Glycan Microarray Assay for Assessing Avidity and Specificity of Influenza A Virus Hemagglutinins at JoVE.com

A Miniaturized Glycan Microarray Assay for Assessing Avidity and Specificity of Influenza A Virus Hemagglutinins

Using a printed glycan microarray strategy, a conventional 96-well plate assay was miniaturized for analysis of influenza A virus hemagglutinin avidity and specificity for sialic acid containing receptors.

Influenza A virus (IAV) hemagglutinins recognize sialic acids on the cell surface as functional receptors to gain entry into cells. Wild waterfowl are the ...

Research

JoVE Journal

Immunology and Infection

Using Bioluminescent Imaging to Investigate Synergism Between Streptococcus pneumoniae and Influenza A Virus in Infant Mice

Using Bioluminescent Imaging to Investigate Synergism Between Streptococcus pneumoniae and Influenza A Virus in Infant Mice

During the 1918 influenza virus pandemic, which killed approximately 50 million people worldwide, the majority of fatalities were not the result of ...

Using a Pan-Viral Microarray Assay (Virochip) to Screen Clinical Samples for Viral Pathogens

Using a Pan-Viral Microarray Assay Virochip to Screen Clinical Samples for Viral Pathogens

The diagnosis of viral causes of many infectious diseases is difficult due to the inherent sequence diversity of viruses as well as the ongoing emergence ...

ampliPHOX Colorimetric Detection on a DNA Microarray for Influenza

DNA microarrays have emerged as a powerful tool for pathogen detection.1-5  For instance, many examples of the ability to type and subtype influenza virus ...

Quantitative Analyses of all Influenza Type A Viral Hemagglutinins and Neuraminidases using Universal Antibodies in Simple Slot Blot Assays

Hemagglutinin (HA) and neuraminidase (NA) are two surface proteins of influenza viruses which are known to play important roles in the viral life cycle ...

High-throughput Detection Method for Influenza Virus

Influenza virus is a respiratory pathogen that causes a high degree of morbidity and mortality every year in multiple parts of the world. Therefore, ...

Co-immunoprecipitation of the Mouse Mx1 Protein with the Influenza A Virus Nucleoprotein

Studying the interaction between proteins is key in understanding their function(s). A very powerful method that is frequently used to study interactions ...

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 ...

In Vitro Disassembly of Influenza A Virus Capsids by Gradient Centrifugation

In Vitro Disassembly of Influenza A Virus Capsids by Gradient Centrifugation

Acid-triggered molecular processes closely control cell entry of many viruses that enter through the endocytic system. In the case of influenza A virus ...

Fluorescence-based Neuraminidase Inhibition Assay to Assess the Susceptibility of Influenza Viruses to The Neuraminidase Inhibitor Class of Antivirals

The neuraminidase (NA) inhibitors are the only class of antivirals approved for the treatment and prophylaxis of influenza that are effective against ...