Nous tenons à remercier le Fonds commun NIH - Protein Programme des réactifs de capture pour le financement du développement de la sélection d&#39;anticorps et la caractérisation pipeline anticorps recombinants Réseau et la Fondation canadienne pour l&#39;innovation pour l&#39;achat de financement de la plate-forme de sélection robotique.

<ol>
	<li>Winter, G., Milstein, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Man-made+antibodies.">Man-made antibodies.</a> Nature. 349, 293-299 (1991).</li><li>Miersch, S., Sidhu, S. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synthetic+antibodies:+concepts,+potential+and+practical+considerations.">Synthetic antibodies: concepts, potential and practical considerations.</a> Methods. 57, 486-498 (2012).</li><li>Schofield, D. J., 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=Application+of+phage+display+to+high+throughput+antibody+generation+and+characterization.">Application of phage display to high throughput antibody generation and characterization.</a> Genome Biol. 8, R254 (2007).</li><li>Hust, 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+human+scFv+antibody+generation+pipeline+for+proteome+research.">A human scFv antibody generation pipeline for proteome research.</a> J. Biotechnol. 152, 159-170 (2011).</li><li>Colwill, K., Graslund, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+roadmap+to+generate+renewable+protein+binders+to+the+human+proteome.">A roadmap to generate renewable protein binders to the human proteome.</a> Nat. Methods. 8, 551-558 (2011).</li><li>Mersmann, 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=Towards+proteome+scale+antibody+selections+using+phage+display.">Towards proteome scale antibody selections using phage display.</a> Nat. Biotechnol. 27, 118-128 (2010).</li><li>Pershad, 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=Generating+a+panel+of+highly+specific+antibodies+to+20+human+SH2+domains+by+phage+display.">Generating a panel of highly specific antibodies to 20 human SH2 domains by phage display.</a> Protein Eng. Des. Sel. 23, 279-288 (2010).</li><li>Turunen, L., Takkinen, K., Soderlund, H., Pulli, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Automated+panning+and+screening+procedure+on+microplates+for+antibody+generation+from+phage+display+libraries.">Automated panning and screening procedure on microplates for antibody generation from phage display libraries.</a> J Biomol. Screen. 14, 282-293 (2009).</li><li>Hughes, R. A., Miklos, A. E., Ellington, A. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gene+synthesis:+methods+and+applications.">Gene synthesis: methods and applications.</a> Methods Enzymol. 498, 277-309 (2011).</li><li>Boersma, Y. L., Pluckthun, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=DARPins+and+other+repeat+protein+scaffolds:+advances+in+engineering+and+applications.">DARPins and other repeat protein scaffolds: advances in engineering and applications.</a> 22, 849-857 (2011).</li><li>Terpe, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Overview+of+tag+protein+fusions:+from+molecular+and+biochemical+fundamentals+to+commercial+systems.">Overview of tag protein fusions: from molecular and biochemical fundamentals to commercial systems.</a> Appl. Microbiol. Biotechnol. 60, 523-533 (2003).</li><li>Lichty, J. J., Malecki, J. L., Agnew, H. D., Michelson-Horowitz, D. J., Tan, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+affinity+tags+for+protein+purification.">Comparison of affinity tags for protein purification.</a> Protein Expr. Purif. 41, 98-105 (2005).</li><li>Fellouse, F. 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=High-throughput+generation+of+synthetic+antibodies+from+highly+functional+minimalist+phage-displayed+libraries.">High-throughput generation of synthetic antibodies from highly functional minimalist phage-displayed libraries.</a> J. Mol. Biol. 373, 924-940 (2007).</li><li>Paduch, 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=Generating+conformation-specific+synthetic+antibodies+to+trap+proteins+in+selected+functional+states.">Generating conformation-specific synthetic antibodies to trap proteins in selected functional states.</a> Methods. 60, 3-14 (2013).</li><li>Studier, F. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Protein+production+by+auto-induction+in+high+density+shaking+cultures.">Protein production by auto-induction in high density shaking cultures.</a> Protein Expr. Purif. 41, 207-234 (2005).</li><li>Huang, H., Sidhu, S. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Studying+binding+specificities+of+peptide+recognition+modules+by+high-throughput+phage+display+selections.">Studying binding specificities of peptide recognition modules by high-throughput phage display selections.</a> Methods Mol. Biol. 781, 87-97 (2011).</li><li>McLaughlin, M. E., Sidhu, S. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Engineering+and+analysis+of+peptide-recognition+domain+specificities+by+phage+display+and+deep+Sequencing.">Engineering and analysis of peptide-recognition domain specificities by phage display and deep Sequencing.</a> Methods Enzymol. 523, 327-349 (2013).</li><li>Bradford, M. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+rapid+and+sensitive+method+for+the+quantitation+of+microgram+quantities+of+protein+utilizing+the+principle+of+protein-dye+binding.">A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding.</a> Anal. Biochem. 72, 248-254 (1976).</li><li>den Engelsman, J., 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=Strategies+for+the+assessment+of+protein+aggregates+in+pharmaceutical+biotech+product+development.">Strategies for the assessment of protein aggregates in pharmaceutical biotech product development.</a> Pharm. Res. 28, 920-933 (2011).</li><li>Lavinder, J. J., Hari, S. B., Sullivan, B. J., Magliery, T. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High-throughput+thermal+scanning:+a+general,+rapid+dye-binding+thermal+shift+screen+for+protein+engineering.">High-throughput thermal scanning: a general, rapid dye-binding thermal shift screen for protein engineering.</a> J. Am. Chem. Soc. 131, 3794-3795 (2009).</li><li>Fellouse, F. A., Sidhu, S. S., Howard, G. C., MR, K. a. s. e. r. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Making antibodies in bacteria. in Making and Using Antibodies: A Practical Handbook. , 151-172 (2013).</li><li>Acton, T. 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=Preparation+of+protein+samples+for+NMR+structure,+function,+and+small-molecule+screening+studies.">Preparation of protein samples for NMR structure, function, and small-molecule screening studies.</a> Methods in Enzymology. 483, 23-47 (2011).</li><li>Mahon, 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=Comprehensive+interrogation+of+a+minimalist+synthetic+CDR-H3+library+and+its+ability+to+generate+antibodies+with+therapeutic+potential.">Comprehensive interrogation of a minimalist synthetic CDR-H3 library and its ability to generate antibodies with therapeutic potential.</a> J. Mol. Biol. 425, 1712-1730 (2013).</li><li>Persson, 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=CDR-H3+diversity+is+not+required+for+antigen+recognition+by+synthetic+antibodies.">CDR-H3 diversity is not required for antigen recognition by synthetic antibodies.</a> J. Mol. Biol. 425, 803-811 (2013).</li><li>Bradbury, A. R., Sidhu, S., Dubel, S., McCafferty, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Beyond+natural+antibodies:+the+power+of+in+vitro+display+technologies.">Beyond natural antibodies: the power of in vitro display technologies.</a> Nat. Biotechnol. 29, 245-254 (2011).</li></ol>

Les auteurs ne ont rien à divulguer.

Lors de la conduite dans les sélections d&#39;anticorps in vitro, les deux principaux déterminants de la réussite de sélection sont: 1) l&#39;isolement des cibles antigéniques bien pliés de sélection sur et 2) la disponibilité d&#39;une bibliothèque d&#39;anticorps de la diversité fonctionnelle élevée. Dans de nombreux cas, la disponibilité de quantités suffisantes de bien plié, protéine de pleine longueur peut être un facteur limitant. Une approche pour surmonter cette limitation est ...

Avec le début de l&#39;ère post-génomique, la disponibilité des réactifs de liaison de haute qualité pour caractériser et de moduler les protéines est essentiel pour ouvrir de nouvelles recherches et avenues thérapeutiques. Anticorps continuent d&#39;être critique à la fois aux chercheurs universitaires et industriels que la recherche fondamentale et outils de diagnostic et thérapeutiques potentiels. Sans surprise, il ya eu une croissance impressionnante des entreprises de développement d&#39;anticorps du contrat, dont la plupart se appuient sur des technologies classiques d&#39;hybridomes pour générer des anticorps personnalisés. Néanmoins, la sélection in vitro en utilisant des bibliothèques d&#39;anticorps phages devient une technologie alternative puissante qui peut offrir des avantages et des succès uniques où les technologies conventionnelles peuvent rencontrer des limitations 1, 2. À la lumière de la demande considérable pour les anticorps de haute qualité comme outils de recherche, deux principaux défis pour générer des anticorps renouvelables sont 1) le débit de sélection et 2) l&#39;antigène availability. Un certain nombre de groupes ont maintenant décrit dans les pipelines de sélection in vitro visant à augmenter le débit et le taux de l&#39;identification d&#39;anticorps. Ces descriptions en détail une variété d&#39;approches viables qui incluent le choix soit sur ​​toute la longueur cible 3,4, 5,6,7 ou des domaines structurellement liée, en utilisant soit 6,8 ou une plaque à base de 3,4 régimes antigène d&#39;immobilisation sur la base de perles. En outre, l&#39;adoption croissante des technologies de synthèse de gènes neuf a fait la production de l&#39;antigène systématique, en particulier des domaines isolés, raisonnablement rentable et peut potentiellement atténuer la difficulté d&#39;obtenir des quantités suffisantes de l&#39;antigène purifié, pleine longueur. En utilisant les deux technologies en tandem, un pipeline autonome et la production de l&#39;antigène évolutive et la sélection d&#39;anticorps a été conçu qui permettrait l&#39;isolement d&#39;anticorps parallèle pour les grands ensembles de domaines antigène exprimé et faciliter le développement de réactifs pour characterizing classes entières de protéines structurellement ou fonctionnellement liés. Vers cet objectif, un pipeline intégré que les couples dans l&#39;identification in silico de domaines d&#39;antigène exprimables, synthèse de gènes, expression bactérienne à haut débit des antigènes et des sélections d&#39;anticorps de phages évolutives a été développé. Ce pipeline ne nécessite que l&#39;infrastructure de base disponible pour la plupart des laboratoires de sciences de la vie (y compris les bibliothèques d&#39;anticorps qui sont de plus en plus disponible via une licence ou un accord de transfert de matériel), mais est également prête à l&#39;automatisation pour une utilisation à l&#39;échelle industrielle. En utilisant ce protocole, il est possible de générer des centaines de domaines d&#39;antigène étiqueté par affinité, et d&#39;isoler des fragments d&#39;anticorps habituellement hautement spécifiques à un grand nombre de ces antigènes. La technologie de présentation de phage a montré la compatibilité démontrée avec une grande variété de formats de réactifs d&#39;affinité recombinants, y compris les fragments Fab, scFv, Fv et des domaines autonomes et unnombre croissant de petites «cadres alternatifs» (protéines de répétition ankyrine conçus (DARPINS), fibronectine (Fn), domaines de LIPOCALINE et plus 10). Discussion est limité dans cet exemple à l&#39;isolement de fragments d&#39;anticorps Fab, même si on suppose ces procédés peuvent être adaptés à d&#39;autres types de bibliothèques. En utilisant cette technologie, Fab ayant un faible nanomolaire affinité à petit, tagged domaines de protéines y compris des domaines de facteurs de transcription, des domaines SH2, de l&#39;ARN des protéines de liaison et d&#39;autres ont été sélectionnés avec succès, dont plusieurs se lient protéine de pleine longueur et sont fonctionnels dans des analyses immunologiques telles que l&#39;immunofluorescence , immunoprécipitation et immunohistochimie. Fait important, les clones de liaison recombinantes sont entièrement renouvelables et peuvent être re-générés à partir de constructions d&#39;expression via bactérienne offre de production accrue cohérence, la reproductibilité et la rentabilité, justifiant ainsi la charge de la validation de clone rigoureuse. Dans cette protocol et vidéo qui l&#39;accompagne, les méthodes de base pour la sélection d&#39;anticorps à partir de banques de phages en utilisant les domaines d&#39;antigènes immobilisés sont démontrés. Cette méthode particulière emploie domaines protéiques étiquetée GST immobilisées par adsorption passive dans des plaques de microtitration, bien que d&#39;autres mots-clés 11,12,13 et les formats de sélection 13,14,2 ont également été utilisés avec succès. Considérations critiques pour la configuration et la conduite des sélections avec contrôle parallèle de paramètres de sélection visant à identifier et isoler anticorps monoclonaux spécifiquement enrichis pour la validation sont détaillées.

<table border="0" cellpadding="0" cellspacing="0" width="470">
	<tbody>
		<tr height="22">
			<td colspan="4" height="22" style="height:22px;width:471px;">MATERIALS</td>
		</tr>
		<tr height="43">
			<td colspan="2" height="43" style="height:43px;width:249px;">Name</td>
			<td style="width:135px;">Company</td>
			<td style="width:87px;">Catalog Number</td>
		</tr>
		<tr height="40">
			<td colspan="2" height="40" style="height:40px;width:249px;">New Brunswick Innova44 stackable incubator shaker</td>
			<td style="width:135px;">Eppendorf</td>
			<td style="width:87px;">M1282-0004</td>
		</tr>
		<tr height="40">
			<td colspan="2" height="40" style="height:40px;width:249px;">Liquidator 96 channel manual benchtop pipetting system</td>
			<td style="width:135px;">Anachem Ltd</td>
			<td style="width:87px;">LIQ-96-200</td>
		</tr>
		<tr height="22">
			<td colspan="2" height="22" style="height:22px;width:249px;">Microplate shaker</td>
			<td style="width:135px;">VWR</td>
			<td style="width:87px;">12620-926</td>
		</tr>
		<tr height="40">
			<td colspan="2" height="40" style="height:40px;width:249px;">ThermoScientific Sorvall ST-40 benchtop centrifuge</td>
			<td style="width:135px;">Thermo Product</td>
			<td style="width:87px;">75004525</td>
		</tr>
		<tr height="40">
			<td colspan="2" height="40" style="height:40px;width:249px;">ELx405 Select Deep Well Microplate Washer</td>
			<td style="width:135px;">Biotek</td>
			<td>ELX405USD</td>
		</tr>
		<tr height="41">
			<td colspan="2" height="41" style="height:41px;width:249px;">Custom High Throughput Automated Phage Selection Robot</td>
			<td style="width:135px;">S&#38;P Robotics</td>
			<td style="width:87px;"></td>
		</tr>
		<tr height="21">
			<td colspan="2" height="21" style="height:21px;width:249px;">Plastic conical Falcon tube: 50 mL</td>
			<td style="width:135px;">VWR</td>
			<td style="width:87px;">21008-178</td>
		</tr>
		<tr height="21">
			<td colspan="2" height="21" style="height:21px;width:249px;">Plastic conical Falcon tube: 15 mL</td>
			<td style="width:135px;">VWR</td>
			<td style="width:87px;">89039-668</td>
		</tr>
		<tr height="21">
			<td colspan="2" height="21" style="height:21px;width:249px;">Axygen 1.7 mL microcentrifuge tubes</td>
			<td style="width:135px;">Corning</td>
			<td style="width:87px;">MCT-175-L-C</td>
		</tr>
		<tr height="21">
			<td colspan="2" height="21" style="height:21px;width:249px;">96-well/384-well Maxisorp plate</td>
			<td style="width:135px;">Sigma</td>
			<td style="width:87px;">M9410-1CS</td>
		</tr>
		<tr height="21">
			<td colspan="2" height="21" style="height:21px;width:249px;">Corning 96-well V-bottom deep-well block</td>
			<td style="width:135px;">Corning</td>
			<td style="width:87px;">3960</td>
		</tr>
		<tr height="21">
			<td colspan="2" height="21" style="height:21px;width:249px;">Axygen Mini-tube 96-well sterile microplate blue box</td>
			<td style="width:135px;">Corning</td>
			<td style="width:87px;">AXY-MTS-06-C-R-S</td>
		</tr>
		<tr height="21">
			<td colspan="2" height="21" style="height:21px;width:249px;">Breathable adhesive plate sealing film</td>
			<td style="width:135px;">VWR</td>
			<td style="width:87px;">60941-084</td>
		</tr>
		<tr height="22">
			<td colspan="4" height="22" style="height:22px;width:471px;">REAGENTS</td>
		</tr>
		<tr height="43">
			<td colspan="2" height="43" style="height:43px;width:249px;">Name</td>
			<td style="width:135px;">Company</td>
			<td style="width:87px;">Catalog Number</td>
		</tr>
		<tr height="22">
			<td colspan="2" height="22" style="height:22px;width:249px;">polyethylene glycol</td>
			<td style="width:135px;">Bioshop</td>
			<td style="width:87px;">PEG800.1</td>
		</tr>
		<tr height="18">
			<td colspan="2" height="18" style="height:18px;">yeast extract</td>
			<td>Bioshop</td>
			<td>YEX401.1</td>
		</tr>
		<tr height="22">
			<td colspan="2" height="22" style="height:22px;width:249px;">bio-tryptone</td>
			<td style="width:135px;">Bioshop</td>
			<td style="width:87px;">TRP402.1</td>
		</tr>
		<tr height="22">
			<td colspan="2" height="22" style="height:22px;width:249px;">N-Z amine</td>
			<td style="width:135px;">Sigma</td>
			<td style="width:87px;">C7290</td>
		</tr>
		<tr height="22">
			<td colspan="2" height="22" style="height:22px;width:249px;">glucose</td>
			<td style="width:135px;">Sigma</td>
			<td style="width:87px;">G8270-1KG</td>
		</tr>
		<tr height="22">
			<td colspan="2" height="22" style="height:22px;width:249px;">lactose</td>
			<td style="width:135px;">Bioshop</td>
			<td style="width:87px;">LAC234</td>
		</tr>
		<tr height="22">
			<td colspan="2" height="22" style="height:22px;width:249px;">glycerol</td>
			<td style="width:135px;">Bioshop</td>
			<td>GLY001.500</td>
		</tr>
		<tr height="22">
			<td colspan="2" height="22" style="height:22px;width:249px;">carbenicillin&#160;</td>
			<td style="width:135px;">Bioshop</td>
			<td style="width:87px;">CAR544.10</td>
		</tr>
		<tr height="22">
			<td colspan="2" height="22" style="height:22px;width:249px;">kanamycin</td>
			<td style="width:135px;">Bioshop</td>
			<td style="width:87px;">KAN201.25</td>
		</tr>
		<tr height="22">
			<td colspan="2" height="22" style="height:22px;width:249px;">tetracycline&#160;</td>
			<td style="width:135px;">Bioshop</td>
			<td style="width:87px;">TET701.25</td>
		</tr>
		<tr height="43">
			<td colspan="2" height="43" style="height:43px;width:249px;">Tween 20</td>
			<td style="width:135px;">Bioshop</td>
			<td style="width:87px;">TWN510.500</td>
		</tr>
		<tr height="21">
			<td colspan="2" height="21" style="height:21px;width:249px;">monobasic potassium phophate</td>
			<td style="width:135px;">Bioshop</td>
			<td style="width:87px;">PPM302.1</td>
		</tr>
		<tr height="21">
			<td colspan="2" height="21" style="height:21px;width:249px;">dibasic sodium phosphate</td>
			<td style="width:135px;">Anachemia</td>
			<td style="width:87px;">84486-440</td>
		</tr>
		<tr height="21">
			<td colspan="2" height="21" style="height:21px;width:249px;">sodium chloride</td>
			<td style="width:135px;">Bioshop</td>
			<td style="width:87px;">SOD001.10</td>
		</tr>
		<tr height="21">
			<td colspan="2" height="21" style="height:21px;width:249px;">potassium chloride</td>
			<td style="width:135px;">Bioshop</td>
			<td style="width:87px;">POC308.1</td>
		</tr>
		<tr height="20">
			<td colspan="2" height="20" style="height:20px;width:249px;">calcium chloride</td>
			<td style="width:135px;">Bioshop</td>
			<td style="width:87px;">CCL302.500</td>
		</tr>
		<tr height="21">
			<td colspan="2" height="21" style="height:21px;width:249px;">magnesium sulphate</td>
			<td style="width:135px;">EMD</td>
			<td style="width:87px;">MX0070-1</td>
		</tr>
		<tr height="21">
			<td colspan="2" height="21" style="height:21px;width:249px;">magnesium chloride</td>
			<td style="width:135px;">Bioshop</td>
			<td style="width:87px;">MAG510.500</td>
		</tr>
		<tr height="21">
			<td colspan="2" height="21" style="height:21px;width:249px;">NH4Cl</td>
			<td style="width:135px;">Amresco</td>
			<td style="width:87px;">0621-1KG</td>
		</tr>
		<tr height="21">
			<td colspan="2" height="21" style="height:21px;width:249px;">Na2SO4</td>
			<td style="width:135px;">Bioshop</td>
			<td style="width:87px;">SOS513.500</td>
		</tr>
		<tr height="21">
			<td colspan="2" height="21" style="height:21px;width:249px;">agar</td>
			<td style="width:135px;">Bioshop</td>
			<td style="width:87px;">AGR001.500</td>
		</tr>
		<tr height="21">
			<td colspan="2" height="21" style="height:21px;width:249px;">SybrSafe DNA gel stain</td>
			<td style="width:135px;">Invitrogen</td>
			<td style="width:87px;">S33102</td>
		</tr>
		<tr height="21">
			<td colspan="2" height="21" style="height:21px;width:249px;">phosphoric acid</td>
			<td style="width:135px;">Acros Organics</td>
			<td style="width:87px;">201140010</td>
		</tr>
		<tr height="21">
			<td colspan="2" height="21" style="height:21px;width:249px;">lysozyme</td>
			<td style="width:135px;">Bioshop</td>
			<td style="width:87px;">LYS702.25</td>
		</tr>
		<tr height="21">
			<td colspan="2" height="21" style="height:21px;width:249px;">benzonase</td>
			<td style="width:135px;">Novagen</td>
			<td style="width:87px;">71205</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:139px;">Triton X-100</td>
			<td style="width:111px;"></td>
			<td style="width:135px;">Bioshop</td>
			<td style="width:87px;">TRX506.500</td>
		</tr>
		<tr height="21">
			<td colspan="2" height="21" style="height:21px;width:249px;">protease inhibitor cocktail tablets</td>
			<td style="width:135px;">Roche</td>
			<td style="width:87px;">11 836 170 001</td>
		</tr>
		<tr height="22">
			<td colspan="2" height="22" style="height:22px;width:249px;">Ni-NTA resin&#160;</td>
			<td style="width:135px;">Qiagen</td>
			<td style="width:87px;">1018240</td>
		</tr>
		<tr height="42">
			<td colspan="2" height="42" style="height:43px;width:249px;">1000x helper phage (M13K07) stock (1013 phage per mL)</td>
			<td style="width:135px;">NEB</td>
			<td style="width:87px;">N0315S</td>
		</tr>
		<tr height="21">
			<td colspan="2" height="39" rowspan="2" style="height:40px;width:249px;">HRP conjugated M13-specific antibody (anti-M13-HRP).</td>
			<td rowspan="2" style="width:135px;">GE Healthcare</td>
			<td rowspan="2" style="width:87px;">27-9241-01</td>
		</tr>
		<tr height="18">
		</tr>
		<tr height="44">
			<td colspan="2" height="44" style="height:44px;width:249px;">TMB substrate: mix equal volumes of TMB and H2O2 peroxidase substrate&#160;</td>
			<td style="width:135px;">KPL</td>
			<td style="width:87px;">50-76-00</td>
		</tr>
		<tr height="22">
			<td colspan="2" height="22" style="height:22px;width:249px;">dNTPs</td>
			<td style="width:135px;">Biobasic</td>
			<td style="width:87px;">DD0056</td>
		</tr>
		<tr height="22">
			<td colspan="2" height="22" style="height:22px;width:249px;">Taq polymerase</td>
			<td style="width:135px;">Genscript</td>
			<td style="width:87px;">E00007</td>
		</tr>
		<tr height="22">
			<td colspan="2" height="22" style="height:22px;width:249px;">Exonuclease</td>
			<td style="width:135px;">GE Healthcare&#160;</td>
			<td style="width:87px;">EZ0073X-EZ</td>
		</tr>
		<tr height="22">
			<td colspan="2" height="22" style="height:22px;width:249px;">Shrimp alkaline phosphatase</td>
			<td style="width:135px;">GE Healthcare</td>
			<td style="width:87px;">E70092Z-EZ</td>
		</tr>
	</tbody>
</table>

scalable high throughput selection from  phage-displayed synthetic antibody libraries

La demande pour les anticorps qui répondent aux besoins des deux applications de la recherche fondamentale et clinique est élevé et va augmenter considérablement dans l&#39;avenir. Cependant, il est évident que les techniques traditionnelles monoclonaux ne sont pas seuls à cette entrée. Cela a conduit au développement de méthodes alternatives pour satisfaire la demande de haute qualité et de réactifs d&#39;affinité renouvelables accessibles à tous les éléments du protéome. À cette fin, méthodes à haut débit pour la conduite des sélections de bibliothèques d&#39;anticorps synthétiques phages ont été conçus pour des applications impliquant divers antigènes et optimisé pour un débit rapide et le succès. Ici, un protocole est décrit en détail qui illustre avec la sélection vidéo manifestation parallèle clones de Fab-phage à partir de bibliothèques de grande diversité contre des centaines de cibles à l&#39;aide soit d&#39;un gestionnaire de liquide 96 manuel de canal automatique ou système robotique. En utilisant ce protocole, un seul utilisateur peut générer des centaines d&#39;antigènes,sélectionner des anticorps à eux en parallèle et valider contraignant dans les six à huit semaines anticorps. Surbrillance sont: i) un format de l&#39;antigène viable, ii) l&#39;antigène pré-sélection caractérisation, iii) les étapes critiques qui influencent la sélection de clones spécifiques et de haute affinité, et iv) les moyens de l&#39;efficacité de la sélection de la surveillance et stade précoce anticorps clone caractérisation. Avec cette approche, nous avons obtenu des fragments d&#39;anticorps synthétiques (FABS) à de nombreuses catégories de cibles, y compris les récepteurs à passage unique membranaires, hormones protéiques sécrétées et les protéines intracellulaires multi-domaines. Ces fragments sont facilement convertis à des anticorps pleine longueur et ont été validés à présenter une grande affinité et spécificité. En outre, il a été démontré pour être fonctionnels dans une variété de dosages immunologiques standard, y compris Western blot, ELISA, l&#39;immunofluorescence cellulaire, des dosages d&#39;immunoprécipitation et connexes. Cette méthodologie permettra d&#39;accélérer la découverte d&#39;anticorps et, finalement, de nous rapprocher de la réalisation de l&#39;objectif of générer renouvelables, des anticorps de haute qualité à la protéome.

Le protocole décrit ci-après a été utilisé pour isoler des fragments d&#39;anticorps à une variété de deux domaines antigéniques structurellement et fonctionnellement liées à partir de banques combinatoires de phages de Fab en parallèle. Les problèmes liés à la disponibilité de l&#39;antigène peuvent être contournés, dans de nombreux cas, par l&#39;identification in silico des domaines antigéniques exprimables qui sont appropriés pour la sélection 23 d&#39;anticorps. En couplant l&#39;ex...

Watch this Scientific Journal Video about Scalable High Throughput Selection From  Phage-displayed Synthetic Antibody Libraries at JoVE.com

Scalable High Throughput Selection From  Phage-displayed Synthetic Antibody Libraries

Une méthode est décrite avec accompagnement visuel pour mener évolutives, des sélections à haut débit à partir de banques d&#39;anticorps combinatoires synthétiques de phages contre des centaines d&#39;antigènes simultanément. En utilisant cette approche parallèle, nous avons isolé des fragments d&#39;anticorps qui présentent une affinité et une spécificité pour divers antigènes qui sont fonctionnelles dans des dosages immunologiques standard.

Scalable High Throughput sélection à partir de bibliothèques d&#39;anticorps synthétiques phage

The demand for antibodies that fulfill the needs of both basic and clinical research applications is high and will dramatically increase in the future. ...

scalable-high-throughput-selection-from-phage-displayed-synthetic

Research

JoVE Journal

Immunology and Infection

18.4K vues.  The Recombinant Antibody Network.  Une méthode est décrite avec accompagnement visuel pour mener évolutives, des sélections à haut débit à partir de banques d'anticorps combinatoires synthétiques de phages contre des centaines d'antigènes simultanément. En utilisant cette approche parallèle, nous avons isolé des fragments d'anticorps qui présentent une affinité et une spécificité pour divers antigènes qui sont fonctionnelles dans des dosages immunologiques standard. 

Vidéo: Scalable High Throughput Selection From  Phage-displayed Synthetic Antibody Libraries

Separation of Single-stranded DNA, Double-stranded DNA and RNA from an Environmental Viral Community Using Hydroxyapatite Chromatography

Viruses, particularly bacteriophages (phages), are the most numerous biological entities on Earth1,2. Viruses modulate host cell abundance and diversity, contribute to the cycling of nutrients, alter host cell phenotype, and influence the evolution of both host cell and viral communities through the lateral transfer of genes 3. Numerous studies have highlighted the staggering genetic diversity of viruses and their functional potential in a variety of natural environments. 
Metagenomic techniques have been used to study the taxonomic diversity and functional potential of complex viral assemblages whose members contain single-stranded DNA (ssDNA), double-stranded DNA (dsDNA) and RNA genotypes 4-9. Current library construction protocols used to study environmental DNA-containing or RNA-containing viruses require an initial nuclease treatment in order to remove nontargeted templates 10. However, a comprehensive understanding of the collective gene complement of the virus community and virus diversity requires knowledge of all members regardless of genome composition. Fractionation of purified nucleic acid subtypes provides an effective mechanism by which to study viral assemblages without sacrificing a subset of the community&#x2019;s genetic signature. 
Hydroxyapatite, a crystalline form of calcium phosphate, has been employed in the separation of nucleic acids, as well as proteins and microbes, since the 1960s11. By exploiting the charge interaction between the positively-charged Ca2+ ions of the hydroxyapatite and the negatively charged phosphate backbone of the nucleic acid subtypes, it is possible to preferentially elute each nucleic acid subtype independent of the others. We recently employed this strategy to independently fractionate the genomes of ssDNA, dsDNA and RNA-containing viruses in preparation of DNA sequencing 12. Here, we present a method for the fractionation and recovery of ssDNA, dsDNA and RNA viral nucleic acids from mixed viral assemblages using hydroxyapatite chromotography.

We describe an efficient method to separate single-stranded DNA, double-stranded DNA and RNA molecules from environmental viral communities. Nucleic acids are fractionated using hydroxyapatite chromatography with increasing concentrations of phosphate-containing buffers. This method permits the isolation of all viral nucleic acid types from environmental samples.

Séparation de l&#39;ADN simple brin, double brin de l&#39;ADN et l&#39;ARN à partir d&#39;un environnement communautaire viral en utilisant chromatographie d&#39;hydroxyapatite

Viruses, particularly bacteriophages (phages), are the most numerous biological entities on Earth1,2.  Viruses modulate host cell abundance and diversity, ...

Recherche

Immunologie et infection

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, precise diagnosis of the infecting strain and rapid high-throughput screening of vast numbers of clinical samples is paramount to control the spread of pandemic infections. Current clinical diagnoses of influenza infections are based on serologic testing, polymerase chain reaction, direct specimen immunofluorescence and cell culture 1,2.
Here, we report the development of a novel diagnostic technique used to detect live influenza viruses. We used the mouse-adapted human A/PR/8/34 (PR8, H1N1) virus 3 to test the efficacy of this technique using MDCK cells 4. MDCK cells (104 or 5 x 103 per well) were cultured in 96- or 384-well plates, infected with PR8 and viral proteins were detected using anti-M2 followed by an IR dye-conjugated secondary antibody. M2 5 and hemagglutinin 1 are two major marker proteins used in many different diagnostic assays. Employing IR-dye-conjugated secondary antibodies minimized the autofluorescence associated with other fluorescent dyes. The use of anti-M2 antibody allowed us to use the antigen-specific fluorescence intensity as a direct metric of viral quantity. To enumerate the fluorescence intensity, we used the LI-COR Odyssey-based IR scanner. This system uses two channel laser-based IR detections to identify fluorophores and differentiate them from background noise. The first channel excites at 680 nm and emits at 700 nm to help quantify the background. The second channel detects fluorophores that excite at 780 nm and emit at 800 nm. Scanning of PR8-infected MDCK cells in the IR scanner indicated a viral titer-dependent bright fluorescence. A positive correlation of fluorescence intensity to virus titer starting from 102-105 PFU could be consistently observed. Minimal but detectable positivity consistently seen with 102-103 PFU PR8 viral titers demonstrated the high sensitivity of the near-IR dyes. The signal-to-noise ratio was determined by comparing the mock-infected or isotype antibody-treated MDCK cells.
Using the fluorescence intensities from 96- or 384-well plate formats, we constructed standard titration curves. In these calculations, the first variable is the viral titer while the second variable is the fluorescence intensity. Therefore, we used the exponential distribution to generate a curve-fit to determine the polynomial relationship between the viral titers and fluorescence intensities. Collectively, we conclude that IR dye-based protein detection system can help diagnose infecting viral strains and precisely enumerate the titer of the infecting pathogens.

This method describes the use of Infrared dye based imaging system for detection of H1N1 in bronchioalveolar lavage (BAL) fluid of infected mice at a high sensitivity. This methodology can be performed in a 96- or 384-well plate, requires &lt;10 &mu;l volume of test material and has the potential for concurrent screening of multiple pathogens.

Méthode de détection à haut débit pour les virus de la grippe

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

Quantitative High-throughput Single-cell Cytotoxicity Assay For T Cells

Cancer immunotherapy can harness the specificity of immune response to target and eliminate tumors. Adoptive cell therapy (ACT) based on the adoptive transfer of T cells genetically modified to express a chimeric antigen receptor (CAR) has shown considerable promise in clinical trials1-4. There are several advantages to using CAR+ T cells for the treatment of cancers including the ability to target non-MHC restricted antigens and to functionalize the T cells for optimal survival, homing and persistence within the host; and finally to induce apoptosis of CAR+ T cells in the event of host toxicity5.
Delineating the optimal functions of CAR+ T cells associated with clinical benefit is essential for designing the next generation of clinical trials. Recent advances in live animal imaging like multiphoton microscopy have revolutionized the study of immune cell function in vivo6,7. While these studies have advanced our understanding of T-cell functions in vivo, T-cell based ACT in clinical trials requires the need to link molecular and functional features of T-cell preparations pre-infusion with clinical efficacy post-infusion, by utilizing in vitro assays monitoring T-cell functions like, cytotoxicity and cytokine secretion. Standard flow-cytometry based assays have been developed that determine the overall functioning of populations of T cells at the single-cell level but these are not suitable for monitoring conjugate formation and lifetimes or the ability of the same cell to kill multiple targets8.
Microfabricated arrays designed in biocompatible polymers like polydimethylsiloxane (PDMS) are a particularly attractive method to spatially confine effectors and targets in small volumes9. In combination with automated time-lapse fluorescence microscopy, thousands of effector-target interactions can be monitored simultaneously by imaging individual wells of a nanowell array. We present here a high-throughput methodology for monitoring T-cell mediated cytotoxicity at the single-cell level that can be broadly applied to studying the cytolytic functionality of T cells.

We describe a single-cell high-throughput assay to measure cytotoxicity of T cells when incubated with tumor target cells. This method employs a dense, elastomeric array of sub-nanoliter wells (~100,000 wells/array) to spatially confine the T cells and target cells at defined ratios and is coupled to fluorescence microscopy to monitor effector-target conjugation and subsequent apoptosis.

Quantitative à haut débit Test de cytotoxicité cellulaire unique pour les cellules T

Cancer immunotherapy can harness the specificity of  immune response to target and eliminate tumors. Adoptive cell therapy (ACT)  based on the adoptive ...

ScanLag: High-throughput Quantification of Colony Growth and Lag Time

Growth dynamics are fundamental characteristics of microorganisms. Quantifying growth precisely is an important goal in microbiology. Growth dynamics are affected both by the doubling time of the microorganism and by any delay in growth upon transfer from one condition to another, the lag. The ScanLag method enables the characterization of these two independent properties at the level of colonies originating each from a single cell, generating a two-dimensional distribution of the lag time and of the growth time. In ScanLag, measurement of the time it takes for colonies on conventional nutrient agar plates to be detected is automated on an array of commercial scanners controlled by an in house application. Petri dishes are placed on the scanners, and the application acquires images periodically. Automated analysis of colony growth is then done by an application that returns the appearance time and growth rate of each colony. Other parameters, such as the shape, texture and color of the colony, can be extracted for multidimensional mapping of sub-populations of cells. Finally, the method enables the retrieval of rare variants with specific growth phenotypes for further characterization. The technique could be applied in bacteriology for the identification of long lag that can cause persistence to antibiotics, as well as a general low cost technique for phenotypic screens.

ScanLag is a high-throughput method for measuring the delay in growth, namely lag time, as well as the growth rate of colonies for thousands of cells in parallel. Screening using ScanLag enables the discrimination between long lag-time and slow growth at the level of a single variant.

ScanLag: haut débit Quantification de Colony croissance et décalage

Growth dynamics are fundamental characteristics of microorganisms. Quantifying growth precisely is an important goal in microbiology. Growth dynamics are ...

High Yield Purification of Plasmodium falciparum Merozoites For Use in Opsonizing Antibody Assays

Plasmodium falciparum merozoite antigens are under development as potential malaria vaccines. One aspect of immunity against malaria is the removal of free merozoites from the blood by phagocytic cells. However assessing the functional efficacy of merozoite specific opsonizing antibodies is challenging due to the short half-life of merozoites and the variability of primary phagocytic cells. Described in detail herein is a method for generating viable merozoites using the E64 protease inhibitor, and an assay of merozoite opsonin-dependent phagocytosis using the pro-monocytic cell line THP-1. E64 prevents schizont rupture while allowing the development of merozoites which are released by filtration of treated schizonts. &#160;Ethidium bromide labelled merozoites are opsonized with human plasma samples and added to THP-1 cells. Phagocytosis is assessed by a standardized high throughput protocol. Viable merozoites are a valuable resource for assessing numerous aspects of P. falciparum biology, including assessment of immune function. Antibody levels measured by this assay are associated with clinical immunity to malaria in naturally exposed individuals. The assay may also be of use for assessing vaccine induced antibodies. &#160;

High Yield Purification of Plasmodium falciparum Merozoites For Use in Opsonizing Antibody Assays

Measuring antibody function is key to understanding immunity to Plasmodium falciparum malaria. This method describes the purification of viable merozoites, and measurement of opsonization-dependent phagocytosis by flow cytometry.

High Yield purification de<em&gt; Plasmodium falciparum</em&gt; Mérozoïtes Pour utilisation en opsonisants Anticorps dosages

Plasmodium falciparum merozoite antigens are under development as potential malaria vaccines. One aspect of immunity against malaria is the removal of ...

High-throughput Gene Tagging in Trypanosoma brucei

Improvements in mass spectrometry, sequencing and bioinformatics have generated large datasets of potentially interesting genes. Tagging these proteins can give insights into their function by determining their localization within the cell and enabling interaction partner identification. We recently published a fast and scalable method to generate Trypanosoma brucei cell lines that express a tagged protein from the endogenous locus. The method was based on a plasmid we generated that, when coupled with long primer PCR, can be used to modify a gene to encode a protein tagged at either terminus. This allows the tagging of dozens of trypanosome proteins in parallel, facilitating the large-scale validation of candidate genes of interest. This system can be used to tag proteins for localization (using a fluorescent protein, epitope tag or electron microscopy tag) or biochemistry (using tags for purification, such as the TAP (tandem affinity purification) tag). Here, we describe a protocol to perform the long primer PCR and the electroporation in 96-well plates, with the recovery and selection of transgenic trypanosomes occurring in 24-well plates. With this workflow, hundreds of proteins can be tagged in parallel; this is an order of magnitude improvement to our previous protocol and genome scale tagging is now possible.

High-throughput Gene Tagging in Trypanosoma brucei

Addition of a tag to a protein is a powerful way of gaining insight into its function. Here, we describe a protocol to endogenously tag hundreds of Trypanosoma brucei proteins in parallel such that genome scale tagging is achievable.

Haut-débit Gene Tagging dans<em&gt; Trypanosoma brucei</em

Improvements in mass spectrometry, sequencing and bioinformatics have generated large datasets of potentially interesting genes. Tagging these proteins ...

Construction of Synthetic Phage Displayed Fab Library with Tailored Diversity

Demand for monoclonal antibodies (mAbs) in basic research and medicine is increasing yearly. Hybridoma technology has been the dominant method for mAb development since its first report in 1975. As an alternative technology, phage display methods for mAb development are increasingly attractive since Humira, the first phage-derived antibody and one of the best-selling mAbs, was approved for clinical treatment of rheumatoid arthritis in 2002. As a non-animal based mAb development technology, phage display bypasses antigen immunogenicity, humanization, and animal maintenance that are required from traditional hybridoma technology based antibody development. In this protocol, we describe a method for construction of synthetic phage-displayed Fab libraries with diversities of 109-1010 obtainable with a single electroporation. This protocol consists of: 1) high-efficiency electro-competent cell preparation; 2) extraction of uracil-containing single-stranded DNA (dU-ssDNA); 3) Kunkel&#39;s method based oligonucleotide-directed mutagenesis; 4) electroporation and calculation of library size; 5) protein A/L-based enzyme-linked immunosorbent assay (ELISA) for folding and functional diversity evaluation; and 6) DNA sequence analysis of diversity.

This protocol describes a detailed procedure for the construction of a phage-displayed synthetic antibody library with tailored diversity. Synthetic antibodies have broad applications from basic research to disease diagnostics and therapeutics.

Construction du bactériophage synthétique affiche Fab bibliothèque avec diversité sur mesure

Demand for monoclonal antibodies (mAbs) in basic research and medicine is increasing yearly. Hybridoma technology has been the dominant method for mAb ...

A High-throughput, High-content, Liquid-based C. elegans Pathosystem

The number of new drugs identified by traditional, in vitro screens has waned, reducing the success of this approach in the search for new weapons to combat multiple drug resistance. This has led to the conclusion that researchers do not only need to find new drugs, but also need to develop new ways of finding them. Amongst the most promising candidate methods are whole-organism, in vivo assays that use high-throughput, phenotypic readouts and hosts that range from Caenorhabditis elegans to Danio rerio. These hosts have several powerful advantages, including dramatic reductions in false positive hits, as compounds that are toxic to the host and/or biounavailable are typically dropped in the initial screen, prior to costly follow up.
Here we show how our assay has been used to interrogate host variation in the well-documented C. elegans&#8212;Pseudomonas aeruginosa liquid killing pathosystem. We also demonstrate several extensions of this well-worked out technique. For example, we are able to carry out high-throughput genetic screens using RNAi in 24- or 96-well plate formats to query host factors in this host-pathogen interaction. Using this assay, whole genome screens can be completed in only a few months, which can dramatically simplify the task of identifying drug targets, potentially without the need for laborious biochemical purification approaches.
We also report here a variation of our method that substitutes the gram-positive bacterium Enterococcus faecalis for the gram-negative pathogen P. aeruginosa. Much as is the case for P. aeruginosa, killing by E. faecalis is time-dependent. Unlike previous C. elegans&#8212;E. faecalis assays, our assay for E. faecalis does not require preinfection, improving its safety profile and reducing the chances of contaminating liquid-handling equipment. The assay is highly robust, showing ~95% death rates 96 h post infection.

A High-throughput, High-content, Liquid-based C. elegans Pathosystem

Here we describe a protocol that is an adaptable, whole host, high-content screening tool that can be utilized to study host-pathogen interactions and be used for drug discovery.

Un haut débit et haute teneur, liquide à base de c. elegans pathosystème

The number of new drugs identified by traditional, in vitro screens has waned, reducing the success of this approach in the search for new weapons to ...

A High-throughput Shigella-specific Bactericidal Assay

Serum bactericidal assays (SBAs) measure the functional activity of antibodies and have been used for many decades. SBAs directly measure antibody killing activity by assessing the ability of antibodies in serum to bind to bacteria and activate complement. This complement activation results in the lysis and killing of the target bacteria. These assays are valuable because they go beyond quantifying antibody production to elucidate the biological functions that these antibodies have, allowing researchers to study the role that antibodies may play in preventing infection. SBAs have been used to study immune responses for many human pathogens, but there is no widely accepted methodology for Shigella at present. Historically, SBAs have been very labor-intensive, requiring many time-consuming steps to accurately quantify surviving bacteria. This protocol describes a simple, robust, and high-throughput assay that measures functional antibodies specific for Shigella in serum in vitro. The method described here offers many advantages over traditional SBAs, including the use of frozen bacterial stocks, 96 well assay plates, a micro-culture system, and automated colony-counting. All of these modifications make this assay less labor-intensive and more high-throughput. This protocol is simpler and faster to perform than traditional SBAs while still using simple technologies and readily available reagents. The protocol has been successfully applied in multiple independent laboratories and the assay is robust and reproducible. The assay can be used to assess immune responses in pre-clinical as well as clinical studies. Quantifying shigellacidal antibody titers both before and after antigen exposure (either by immunization or infection) allows for a broader understanding of how functional antibody responses are generated and their contribution to protective immunity. The development of this standardized, well-characterized assay may greatly facilitate Shigella vaccine design.

A High-throughput Shigella-specific Bactericidal Assay

Here we present a protocol to measure Shigellacidal activity of antibodies in serum. Serum is mixed with bacteria and exogenous complement, incubated, and the reaction mixture is plated on agar plates. Viable bacteria form colonies which are counted, using an automated colony enumerator, and used to determine the bactericidal titer.

Un haut débit de Shigella-test bactéricide spécifique

Serum bactericidal assays (SBAs) measure the functional activity of antibodies and have been used for many decades. SBAs directly measure antibody killing ...

Targeted Antibody Blocking by a Dual-Functional Conjugate of Antigenic Peptide and Fc-III Mimetics (DCAF)

Elimination of harmful antibodies from organisms is a valuable approach for the intervention of antibody-associated diseases, such as Dengue hemorrhagic fever and autoimmune diseases. Since thousands of antibodies with different epitopes are circulating in blood, no universal method, except for the dual-functional conjugate of antigenic peptide and Fc-III mimetics (DCAF), was reported to target specific harmful antibodies. The development of DCAF molecules makes significant contribution to the progress of targeted therapy, which were demonstrated to eliminate the antibody dependent enhancement (ADE) effect in a Dengue virus (DENV) infection model and to boost the acetylcholine receptor activity in a myasthenia gravis model. Here, we describe a protocol for the synthesis of a DCAF molecule (DCAF1), which can selectively block 4G2 antibody to attenuate ADE effect during Dengue virus infection, and illustrate the binding of DCAF1 to 4G2 antibody by an ELISA assay. In our method, DCAF1 is synthesized by the conjugation of a hydrazine derivative of a Fc-III peptide and a recombinant expressed long &#945;-helix with antigenic sequence through native chemical ligation (NCL). This protocol has been successfully applied to DCAF1 as well as other DCAF molecules for targeting their cognate antibodies.

Targeted Antibody Blocking by a Dual-Functional Conjugate of Antigenic Peptide and Fc-III Mimetics DCAF

Development of a dual-functional conjugate of antigenic peptide and Fc-III mimetics (DCAF) is novel for the elimination of harmful antibodies. Here, we describe a detailed protocol for the synthesis of DCAF1 molecule, which can selectively block 4G2 antibody to eliminate antibody dependent enhancement effect during Dengue virus infection.

Blocage ciblé d'anticorps par un conjugaison bifonctionnel de peptide antigénique et de mimétrie fc-III (DCAF)

Elimination of harmful antibodies from organisms is a valuable approach for the intervention of antibody-associated diseases, such as Dengue hemorrhagic ...