Name: chemical conjugation of a purified dec-205-directed antibody with full-length protein for targeting mouse dendritic cells in vitro and in vivo
Uploaded: 2021-02-05T14:00:00
Description: Watch this Scientific Journal Video about Chemical Conjugation of a Purified DEC-205-Directed Antibody with Full-Length Protein for Targeting Mouse Dendritic Cells In Vitro and In Vivo at JoVE.com

The authors thank S. Prettin for expert technical assistance. This work was supported by a grant of the Helmholtz Association of German Research Centers (HGF) that was provided as part of the Helmholtz Alliance &#39;&#39;Immunotherapy of Cancers&#34; (HCC_WP2b).

All of the described animal experiments were approved by the local government agency (Nieders&#228;chsisches Landesamt f&#252;r Verbraucherschutz und Lebensmittelsicherheit; file number 33.12-42502-04-10/0108) and were performed according to the national and institutional guidelines.
1. Production of &#945;DEC-205 from the hybridoma cell line NLDC-145
<ol>
	<li>For antibody production, thaw cryopreserved NLDC-145 cells producing &#945;DEC-205 at 37 &#176;C in a water bath. Expand the cells a...

<ol>
	<li>Amon, L., Hatscher, L., Heger, L., Dudziak, D., Lehmann, C. H. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Harnessing+the+complete+repertoire+of+conventional+dendritic+cell+functions+for+cancer+immunotherapy.">Harnessing the complete repertoire of conventional dendritic cell functions for cancer immunotherapy.</a> Pharmaceutics. 12 (7), 12070663 (2020).</li><li>Banchereau, 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=Immunobiology+of+dendritic+cells.">Immunobiology of dendritic cells.</a> Annual Review of Immunology. 18, 767-811 (2000).</li><li>Wculek, S. 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=Dendritic+cells+in+cancer+immunology+and+immunotherapy.">Dendritic cells in cancer immunology and immunotherapy.</a> Nature Reviews: Immunology. 20 (1), 7-24 (2020).</li><li>Kastenmuller, W., Kastenmuller, K., Kurts, C., Seder, R. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dendritic+cell-targeted+vaccines--hope+or+hype.">Dendritic cell-targeted vaccines--hope or hype.</a> Nature Reviews: Immunology. 14 (10), 705-711 (2014).</li><li>Bonifaz, L. 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=In+vivo+targeting+of+antigens+to+maturing+dendritic+cells+via+the+DEC-205+receptor+improves+T+cell+vaccination.">In vivo targeting of antigens to maturing dendritic cells via the DEC-205 receptor improves T cell vaccination.</a> Journal of Experimental Medicine. 199 (6), 815-824 (2004).</li><li>Boscardin, S. 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=Antigen+targeting+to+dendritic+cells+elicits+long-lived+T+cell+help+for+antibody+responses.">Antigen targeting to dendritic cells elicits long-lived T cell help for antibody responses.</a> Journal of Experimental Medicine. 203 (3), 599-606 (2006).</li><li>Hossain, M. K., Wall, K. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+Dendritic+Cell+Receptors+as+Targets+for+Enhancing+Anti-Cancer+Immune+Responses.">Use of Dendritic Cell Receptors as Targets for Enhancing Anti-Cancer Immune Responses.</a> Cancers. 11 (3), 11030418 (2019).</li><li>Johnson, T. 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=Inhibition+of+melanoma+growth+by+targeting+of+antigen+to+dendritic+cells+via+an+anti-DEC-205+single-chain+fragment+variable+molecule.">Inhibition of melanoma growth by targeting of antigen to dendritic cells via an anti-DEC-205 single-chain fragment variable molecule.</a> Clinical Cancer Research. 14 (24), 8169-8177 (2008).</li><li>Trumpfheller, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+microbial+mimic+poly+IC+induces+durable+and+protective+CD4++T+cell+immunity+together+with+a+dendritic+cell+targeted+vaccine.">The microbial mimic poly IC induces durable and protective CD4+ T cell immunity together with a dendritic cell targeted vaccine.</a> Proceedings of the National Academy of Sciences of the United States of America. 105 (7), 2574-2579 (2008).</li><li>Idoyaga, 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=Comparable+T+helper+1+(Th1)+and+CD8+T-cell+immunity+by+targeting+HIV+gag+p24+to+CD8+dendritic+cells+within+antibodies+to+Langerin,+DEC205,+and+Clec9A.">Comparable T helper 1 (Th1) and CD8 T-cell immunity by targeting HIV gag p24 to CD8 dendritic cells within antibodies to Langerin, DEC205, and Clec9A.</a> Proceedings of the National Academy of Sciences of the United States of America. 108 (6), 2384-2389 (2011).</li><li>Sancho, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tumor+therapy+in+mice+via+antigen+targeting+to+a+novel,+DC-restricted+C-type+lectin.">Tumor therapy in mice via antigen targeting to a novel, DC-restricted C-type lectin.</a> Journal of Clinical Investigation. 118 (6), 2098-2110 (2008).</li><li>Volckmar, 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=Targeted+antigen+delivery+to+dendritic+cells+elicits+robust+antiviral+T+cell-mediated+immunity+in+the+liver.">Targeted antigen delivery to dendritic cells elicits robust antiviral T cell-mediated immunity in the liver.</a> Scientific Reports. 7, 43985 (2017).</li><li>Kraal, G., Breel, M., Janse, M., Bruin, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Langerhans'+cells,+veiled+cells,+and+interdigitating+cells+in+the+mouse+recognized+by+a+monoclonal+antibody.">Langerhans' cells, veiled cells, and interdigitating cells in the mouse recognized by a monoclonal antibody.</a> Journal of Experimental Medicine. 163 (4), 981-997 (1986).</li><li>Volckmar, 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=The+STING+activator+c-di-AMP+exerts+superior+adjuvant+properties+than+the+formulation+poly(I:C)/CpG+after+subcutaneous+vaccination+with+soluble+protein+antigen+or+DEC-205-mediated+antigen+targeting+to+dendritic+cells.">The STING activator c-di-AMP exerts superior adjuvant properties than the formulation poly(I:C)/CpG after subcutaneous vaccination with soluble protein antigen or DEC-205-mediated antigen targeting to dendritic cells.</a> Vaccine. 37 (35), 4963-4974 (2019).</li></ol>

Chemical conjugation of an endocytosis receptor-specific antibody and a protein antigen provides an efficient and, importantly, also flexible approach for in vivo DC targeting in pre-clinical mouse models. With our protocol we provide an efficient approach for the successful conjugation of the model antigen OVA to a DEC-205-specific IgG antibody.
In our protocol, &#945;DEC-205 is purified from a hybridoma cellline and in the past, we have purified the antibody using protein G sepharos...

Dendritic cells (DC) are central players of the immune system. They are a diverse group of cells specialized in antigen-presentation and their major function is to bridge innate and adaptive immunity1,2. Importantly, DC not only play an important role in efficient and specific pathogen-directed responses but are also involved in many aspects of antitumor immunity1,3.
Due to their exclusive role in host immunity, DC came into focus as target cells for vaccination4. One approach is to target antigens to DC in vivo to induce antigen-specific immune responses and over the last years, a large number of studies have been dedicated to defining suitable receptors and targeting strategies1,4. One example is the C-type lectin receptor DEC-205, which can be targeted by DEC-205-specific antibodies to induce endocytosis. Importantly, DEC-205 targeting in the combination with suitable adjuvants has been shown to efficiently induce long-lived and protective CD4+ and CD8+ T cells, as well as antibody responses, also against tumor antigens3,5,6,7,8,9.
There are a number of studies showing conjugated antigens targeted to DC to be superior to free un-conjugated antigen3,5,10,11,12. This makes the conjugation of the antigen to the respective DC targeting moiety a central step in DC targeting approaches. In the case of DC targeting via antibodies or antibody fragments, antigens can be either chemically or genetically linked and either strategy provides its own (dis)advantages1. On the one hand, in genetically engineered antibody-antigen constructs there is a control over the antigen dose as well as the location providing superior comparability between lots1. At the same time however, chemical conjugation needs less preparation and provides more flexibility especially when attempting to test and compare different antigens and/or vaccination strategies in experimental and pre-clinical models.
Here, we present a protocol for the efficient and reliable chemical conjugation of ovalbumin (OVA) as a model protein antigen to a DEC-205-specific IgG2a antibody (&#945;DEC-205) suitable for in vivo DC targeting in mice. First, &#945;DEC-205 is purified from&#160;NLDC-145 hybridoma cells13. For chemical conjugation, the heterobifunctional crosslinker sulfosuccinimidyl 4-[N-maleimidomethyl] cyclohexane-1-carboxylate (sulfo-SMCC), which contains NHS (N-hydroxysuccinimide) ester and maleimide groups, is used, allowing covalent conjugation of amine- and sulfhydryl-containing molecules. Specifically, the primary amines of the antibody initially react with sulfo-SMCC and the resulting maleimide-activated &#945;DEC-205 then reacts with the sulfhydryl-containing OVA protein reduced through TCEP-HCl (Tris(2-carboxyethyl) phosphine hydrochloride). The final product is chemically conjugated &#945;DEC-205/OVA (Figure 1). Beyond chemical conjugation itself, our protocol describes removal of excess OVA from the conjugate&#160;as well as the verification of successful conjugation through western blot analysis and a specific enzyme-linked immunosorbent assay. We have successfully employed this approach in the past to chemically conjugate OVA and other proteins or immunogenic peptides to &#945;DEC-205. We demonstrate efficient binding to CD11c+ cells in vitro as well as the efficient induction of cellular and humoral immunity in vivo.
Certainly, there are drawbacks to this method such as in lot-to-lot comparability and in the exact dosing of the antigen within the final conjugate. Nevertheless, chemical conjugation provides experimental flexibility in the choice of the antibody and the protein antigen as compared to genetically engineered constructs. Therefore, we believe this approach is especially valuable in evaluating different antigens for their efficiency in DC targeting in pre-clinical mouse models, importantly also in the context of specific antitumor immune responses.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>antibody buffer 2 %</td>
			<td></td>
			<td></td>
			<td>2 % (w/v) Slim-Fast Chocolate powder in TBS-T</td>
		</tr>
		<tr>
			<td>antibody buffer 5 %</td>
			<td></td>
			<td></td>
			<td>5 % milk powder (w/v) in TBS-T</td>
		</tr>
		<tr>
			<td>blocking buffer (ELISA)</td>
			<td></td>
			<td></td>
			<td>10 % FBS in PBS</td>
		</tr>
		<tr>
			<td>blocking buffer 4 %</td>
			<td></td>
			<td></td>
			<td>4 % (w/v) Slim-Fast Chocolate powder in TBS-T</td>
		</tr>
		<tr>
			<td>blocking buffer 10 %</td>
			<td></td>
			<td></td>
			<td>10 % milk powder (w/v) in TBS-T</td>
		</tr>
		<tr>
			<td>cell culture flask T25</td>
			<td>Greiner Bio-One</td>
			<td>690175</td>
			<td>we use standard CELLSTAR filter cap cell culture flasks; alternatively use suspension culture flask (690195 )</td>
		</tr>
		<tr>
			<td>cell culture flask T75</td>
			<td>Greiner Bio-One</td>
			<td>658175</td>
			<td>we use standard CELLSTAR&#160; filter cap cell culture flasks; alternatively use suspension culture flask (658195)&#160;</td>
		</tr>
		<tr>
			<td>cell culture flask T175</td>
			<td>Greiner Bio-One</td>
			<td>661175</td>
			<td>we use standard CELLSTAR filter cap cell culture flasks; alternatively use suspension culture flask (661195)</td>
		</tr>
		<tr>
			<td>centrifugal concentrator MWCO 10 kDa</td>
			<td>Sartorius</td>
			<td>VS2001</td>
			<td>Vivaspin 20 centrifugal concentrator</td>
		</tr>
		<tr>
			<td>centrifugal protein concentrator MWCO 100 kDa, 5 - 20 ml</td>
			<td>Thermo Fisher Scientific</td>
			<td>88532</td>
			<td>Pierce Protein Concentrator, PES 5 -20 ml; we use the Pierce Concentrator 150K MWCO 20mL (catalog number 89921), which is however no longer available&#160;</td>
		</tr>
		<tr>
			<td>centrifuge bottles</td>
			<td>Nalgene</td>
			<td>525-2314</td>
			<td>PPCO (polypropylene copolymer) with PP (polypropylene) screw closure, 500 ml; obtained from VWR, Germany</td>
		</tr>
		<tr>
			<td>coating buffer (ELISA)</td>
			<td></td>
			<td></td>
			<td>0.1 M sodium bicarbonate (NaHCO3) in H2O (pH 9.6)</td>
		</tr>
		<tr>
			<td>desalting columns MWCO 7 kDa</td>
			<td>Thermo Fisher Scientific</td>
			<td>89891</td>
			<td>Thermo Scientific Zeba Spin Desalting Columns, 7K MWCO, 5 mL</td>
		</tr>
		<tr>
			<td>detection reagent ELISA (HRPO substrate)</td>
			<td>Sigma-Aldrich/Merck</td>
			<td>T8665-100ML</td>
			<td>3,3&#8242;,5,5&#8242;-Tetramethylbenzidine (TMB) liquid substrate system</td>
		</tr>
		<tr>
			<td>detection reagent western blot (HRPO substrate)</td>
			<td>Roche/Merck</td>
			<td>12 015 200 01</td>
			<td>Lumi-Light Western Blotting Substrate (Roche)</td>
		</tr>
		<tr>
			<td>dialysis tubing MWCO 12 - 14 kDa</td>
			<td>SERVA Electrophoresis</td>
			<td>44110</td>
			<td>Visking dialysis tubing, 16 mm diameter</td>
		</tr>
		<tr>
			<td>ELISA 96-well plate</td>
			<td>Thermo Fisher Scientific</td>
			<td>442404</td>
			<td>MaxiSorp Nunc-Immuno Plate</td>
		</tr>
		<tr>
			<td>fetal calf serum</td>
			<td>PAN-BIOtech</td>
			<td>P40-47500</td>
			<td>FBS Good forte</td>
		</tr>
		<tr>
			<td>ISF-1 medium</td>
			<td>Biochrom/bioswisstec</td>
			<td>F 9061-01</td>
			<td></td>
		</tr>
		<tr>
			<td>milk powder</td>
			<td>Carl Roth</td>
			<td>T145.2</td>
			<td>powdered milk, blotting grade, low in fat; alternatively we have also used conventional skimmed milk powder from the supermarket</td>
		</tr>
		<tr>
			<td>NLDC-145 hybridoma</td>
			<td>ATCC</td>
			<td>HB-290</td>
			<td>if not already at hand, the hybridoma cells can be acquired from ATCC</td>
		</tr>
		<tr>
			<td>non-reducing SDS sample buffer 4 x&#160;</td>
			<td></td>
			<td></td>
			<td>for 12 ml: 4 ml of 10 % SDS, 600 &#181;l 0.5 M Tris-HCl (ph 6.8), 3.3 ml sterile H2O, 4 ml glycerine, 100 &#181;l of 5 % Bromphenol Blue</td>
		</tr>
		<tr>
			<td>ovalbumin</td>
			<td>Hyglos (via BioVendor)</td>
			<td>321000</td>
			<td>EndoGrade OVA ultrapure with &#60;0.1 EU/mg</td>
		</tr>
		<tr>
			<td>Penicillin/Streptomycin</td>
			<td>Thermo Fisher Scientific</td>
			<td>15140122</td>
			<td>Gibco Penicillin/Streptomycin 10.000 U/ml; alternatively Gibco Penicillin/Streptomycin 5.000 U/ml (15070-063) can be used</td>
		</tr>
		<tr>
			<td>PETG polyethylene terephthalate glycol cell culture roller bottles</td>
			<td>Nunc In Vitro</td>
			<td>734-2394</td>
			<td>standard PDL-coated, vented (1.2X), 1050 cm&#178;, 100 - 500 ml volume; obtained from VWR, Germany&#160;&#160;</td>
		</tr>
		<tr>
			<td>pH indicator strips</td>
			<td>Merck</td>
			<td>109535</td>
			<td>pH indicator strips 0-14</td>
		</tr>
		<tr>
			<td>polyclonal goat &#945;rat-IgG(H+L)-HRPO (western blot)</td>
			<td>Jackson ImmunoResearch&#160;</td>
			<td>112-035-062</td>
			<td>obtained from Dianova, Germany; used at 1:5000 for western blot</td>
		</tr>
		<tr>
			<td>polyclonal goat &#945;rat-IgG+IgM-HRPO antibody&#160; (ELISA)</td>
			<td>Jackson ImmunoResearch&#160;</td>
			<td>112-035-068</td>
			<td>obtained from Dianova, Germany; used at 1:2000 for ELISA</td>
		</tr>
		<tr>
			<td>polyclonal goat &#945;rabbit-IgG-HRPO (western blot)</td>
			<td>Jackson ImmunoResearch&#160;</td>
			<td>111-035-045&#160;</td>
			<td>obtained from Dianova, Germany; used at 1:2000 for western blot</td>
		</tr>
		<tr>
			<td>polyclonal rabbit &#945;OVA (ELISA)</td>
			<td>Abcam</td>
			<td>ab181688</td>
			<td>used at 3 ng/&#181;l</td>
		</tr>
		<tr>
			<td>polyclonal rabbit &#945;OVA antibody (western blot)</td>
			<td>OriGene</td>
			<td>R1101</td>
			<td>used at 1:3,000 for western blot</td>
		</tr>
		<tr>
			<td>Protein G Sepharose column</td>
			<td>Merck/Millipore</td>
			<td>P3296</td>
			<td>5 ml Protein G Sepharose, Fast Flow are packed onto an empty column PD-10 (Merck, GE 17-0435-01)</td>
		</tr>
		<tr>
			<td>protein standard</td>
			<td>Thermo Fisher Scientific</td>
			<td>26616</td>
			<td>PageRuler Prestained Protein ladder 10 - 180 kDa</td>
		</tr>
		<tr>
			<td>PVDF (polyvinylidene difluoride) membrane</td>
			<td>Merck/Millipore</td>
			<td>IPVH00010</td>
			<td>immobilon-P PVDF (polyvinylidene difluoride) membrane</td>
		</tr>
		<tr>
			<td>rubber plug</td>
			<td>Omnilab</td>
			<td>5230217</td>
			<td>DEUTSCH &#38; NEUMANN rubber stoppers (lower &#934; 17 mm; upper &#934; 22 mm)</td>
		</tr>
		<tr>
			<td>silicone tube</td>
			<td>Omnilab</td>
			<td>5430925</td>
			<td>DEUTSCH &#38; NEUMANN (inside &#934; 1 mm; outer &#934; 3 mm)</td>
		</tr>
		<tr>
			<td>Slim-Fast</td>
			<td></td>
			<td></td>
			<td>we have used regular Slim-Fast Chocolate freely available at the pharmacy as in this western blot approach it yielded better results than milk powder</td>
		</tr>
		<tr>
			<td>stopping solution (ELISA)</td>
			<td></td>
			<td></td>
			<td>1M H2SO4</td>
		</tr>
		<tr>
			<td>sulfo-SMCC</td>
			<td>Thermo Fisher Scientific</td>
			<td>22322</td>
			<td>Pierce Sulfo-SMCC Cross-Linker; alternatively use catalog number A39268 (10 x 2 mg)</td>
		</tr>
		<tr>
			<td>syringe filter unit 0.22 &#181;m&#160;</td>
			<td>Merck/Millipore</td>
			<td>SLGV033RS</td>
			<td>Millex-GV Syringe Filter Unit, 0.22 &#181;m, PVDF, 33 mm, gamma sterilized&#160;</td>
		</tr>
		<tr>
			<td>syringe 10 ml</td>
			<td>Omnilab</td>
			<td></td>
			<td>Disposable syringes Injekt&#174; Solo B.Braun</td>
		</tr>
		<tr>
			<td>Sterican&#174; cannulas</td>
			<td>B. Braun</td>
			<td></td>
			<td>Sterican&#174; G 20 x 1 1/2&#34;&#34;; 0.90 x 40 mm; yellow</td>
		</tr>
		<tr>
			<td>TBS-T</td>
			<td></td>
			<td></td>
			<td>Tris-buffered saline containing 0.1 % (v/v) Tween 20</td>
		</tr>
		<tr>
			<td>TCEP-HCl</td>
			<td>Thermo Fisher Scientific</td>
			<td>A35349</td>
			<td></td>
		</tr>
		<tr>
			<td>tubing connector</td>
			<td>Omnilab</td>
			<td></td>
			<td>Kleinfeld miniature tubing connectors for silicone tube</td>
		</tr>
	</tbody>
</table>

chemical conjugation of a purified dec-205-directed antibody with full-length protein for targeting mouse dendritic cells in vitro and in vivo

Targeted antigen delivery to cross-presenting dendritic cells (DC) in vivo efficiently induces T effector cell responses and displays a valuable approach in&#160;vaccine design. Antigen is delivered to DC via antibodies specific for endocytosis receptors such as DEC-205 that induce uptake, processing, and MHC class I- and II-presentation.
Efficient and reliable conjugation of the desired antigen to a suitable antibody is a critical step in DC targeting and among other factors depends on the format of the antigen. Chemical conjugation of&#160;full-length protein to purified antibodies is one possible strategy. In the past, we have successfully established cross-linking of the model antigen ovalbumin (OVA) and a DEC-205-specific IgG2a antibody (&#945;DEC-205)&#160;for in vivo DC targeting studies in mice. The first step of the protocol is the purification of the antibody from the supernatant of the NLDC (non-lymphoid dendritic cells)-145 hybridoma by affinity chromatography. The purified antibody is activated for chemical conjugation by sulfo-SMCC (sulfosuccinimidyl 4-[N-maleimidomethyl] cyclohexane-1-carboxylate) while at the same time the sulfhydryl-groups of the OVA protein are exposed through incubation with TCEP-HCl (tris (2-carboxyethyl) phosphine hydrochloride). Excess TCEP-HCl and sulfo-SMCC are removed and the antigen is mixed with the activated antibody for overnight coupling. The resulting &#945;DEC-205/OVA conjugate is concentrated and freed from unbound OVA. Successful conjugation of OVA to &#945;DEC-205 is verified by western blot analysis and enzyme-linked immunosorbent assay (ELISA).
We have successfully used chemically crosslinked &#945;DEC-205/OVA to induce cytotoxic T cell responses in the liver and to compare different adjuvants for their potential in inducing humoral and cellular immunity following in vivo targeting of DEC-205+ DC. Beyond that, such chemically coupled antibody/antigen conjugates offer valuable tools for the efficient induction of vaccine responses to tumor antigens and have been proven to be superior to classical immunization approaches regarding the prevention and therapy of various types of tumors.

Chemical conjugation of &#945;DEC-205 to OVA protein using this protocol will typically allow efficient generation of &#945;DEC-205/OVA for in vivo DC targeting approaches. There are different strategies to verify the technique itself and to test the functionality of the yielded conjugate. Western blot analysis and ELISA are used to verify successful conjugation and at the same time detect potentially left free OVA (Figure 2). In vitro bindi...

Watch this Scientific Journal Video about Chemical Conjugation of a Purified DEC-205-Directed Antibody with Full-Length Protein for Targeting Mouse Dendritic Cells In Vitro and In Vivo at JoVE.com

Chemical Conjugation of a Purified DEC-205-Directed Antibody with Full-Length Protein for Targeting Mouse Dendritic Cells In Vitro and In Vivo

We describe a protocol for the chemical conjugation of the model antigen ovalbumin to an endocytosis receptor-specific antibody for in vivo dendritic cell targeting. The protocol includes purification of the antibody, chemical conjugation of the antigen, as well as purification of the conjugate and the verification of efficient conjugation.

Chemical Conjugation of a Purified DEC-205-Directed Antibody with Full-Length Protein for Targeting Mouse Dendritic Cells In Vitro and In Vivo

Targeted antigen delivery to cross-presenting dendritic cells (DC) in vivo efficiently induces T effector cell responses and displays a valuable approach ...

Research

JoVE Journal

Cancer Research

In Vitro Imaging and Quantification of the Drug Targeting Efficiency of Fluorescently Labeled GnRH Analogues

In Vitro Imaging and Quantification of the Drug Targeting Efficiency of Fluorescently Labeled GnRH Analogues

GnRH analogues are effective targeting moieties and able to deliver anticancer agents selectively into malignant tumor cells which highly express GnRH ...

Establishing Dual Resistance to EGFR-TKI and MET-TKI in Lung Adenocarcinoma Cells In Vitro with a 2-step Dose-escalation Procedure

Establishing Dual Resistance to EGFR-TKI and MET-TKI in Lung Adenocarcinoma Cells In Vitro with a 2-step Dose-escalation Procedure

Drug resistance is a major challenge in cancer therapy. The generation of resistant sublines in vitro is necessary for discovering novel mechanisms to ...

Counting Proteins in Single Cells with Addressable Droplet Microarrays

Often cellular behavior and cellular responses are analyzed at the population level where the responses of many cells are pooled together as an average ...

Moving Upwards: A Simple and Flexible In Vitro Three-dimensional Invasion Assay Protocol

Moving Upwards: A Simple and Flexible In Vitro Three-dimensional Invasion Assay Protocol

Although 3D invasion assays have been developed, the challenge remains to study cells without affecting the integrity of their microenvironment. ...

In Vivo EPR Assessment of pH, pO2, Redox Status, and Concentrations of Phosphate and Glutathione in the Tumor Microenvironment

In Vivo EPR Assessment of pH, pO2, Redox Status, and Concentrations of Phosphate and Glutathione in the Tumor Microenvironment

This protocol demonstrates the capability of low-field electron paramagnetic resonance (EPR)-based techniques in combination with functional paramagnetic ...

Isolation Protocol of Mouse Monocyte-derived Dendritic Cells and Their Subsequent In Vitro Activation with Tumor Immune Complexes

Isolation Protocol of Mouse Monocyte-derived Dendritic Cells and Their Subsequent In Vitro Activation with Tumor Immune Complexes

Dendritic cells (DC) are heterogeneous cell populations that differ in their cell membrane markers, migration patterns and distribution, and in their ...

A GPC3-targeting Bispecific Antibody, GPC3-S-Fab, with Potent Cytotoxicity

This protocol describes the construction and functional studies of a bispecific antibody (bsAb), GPC3-S-Fab. bsAbs can recognize two different epitopes ...

Phosphopeptide Enrichment Coupled with Label-free Quantitative Mass Spectrometry to Investigate the Phosphoproteome in Prostate Cancer

Phosphoproteomics involves the large-scale study of phosphorylated proteins. Protein phosphorylation is a critical step in many signal transduction ...

In Vivo Immunofluorescence Localization for Assessment of Therapeutic and Diagnostic Antibody Biodistribution in Cancer Research

Monoclonal antibodies (mAbs) are important tools in cancer detection, diagnosis, and treatment. They are used to unravel the role of proteins in ...

In Vivo Targeting of Xenografted Human Cancer Cells with Functionalized Fluorescent Silica Nanoparticles in Zebrafish

Developing nanoparticles capable of detecting, targeting, and destroying cancer cells is of great interest in the field of nanomedicine. In vivo animal ...