Name: laboratory scale production and purification of a therapeutic antibody
Uploaded: 2017-01-24T13:00:00
Description: Watch this Scientific Journal Video about Laboratory Scale Production and Purification of a Therapeutic Antibody at JoVE.com

The research was supported by the University of Sydney. pVITRO1-Trastuzumab-IgG1/&#954; was a gift from Andrew Beavil (Addgene plasmid # 61883). We thank Tihomir S. Dodev for useful discussions regarding pVITRO1-Trastuzumab-IgG1/&#954;.

NOTE: A suitable mammalian expression vector must be used for this protocol. Here, a single construct containing two expression cassettes is used (i.e. heavy and light chain expression is driven by separate promoters). Trastuzumab heavy and light chains were previously cloned into the vector. This vector was a gift from Andrew Beavil, obtained through a not-for-profit plasmid repository 13.
1. Recovery and Scale-up of Vector DNA
NOTE: Vector DNA was received as a soft agar sta...

<ol>
	<li>Nelson, A. L., Reichert, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+trends+for+therapeutic+antibody+fragments.">Development trends for therapeutic antibody fragments.</a> Nat Biotechnol. 27 (4), 331-337 (2009).</li><li>Drake, P. M., Rabuka, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+emerging+playbook+for+antibody-drug+conjugates:+lessons+from+the+laboratory+and+clinic+suggest+a+strategy+for+improving+efficacy+and+safety.">An emerging playbook for antibody-drug conjugates: lessons from the laboratory and clinic suggest a strategy for improving efficacy and safety.</a> Curr Opin Chem Biol. 28, 174-180 (2015).</li><li>Kontermann, R. E., Brinkmann, U. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bispecific+antibodies.">Bispecific antibodies.</a> Drug Discov Today. 20 (7), 838-847 (2015).</li><li>Beck, A., Wurch, T., Bailly, C., Corvaia, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Strategies+and+challenges+for+the+next+generation+of+therapeutic+antibodies.">Strategies and challenges for the next generation of therapeutic antibodies.</a> Nat Rev Immunol. 10 (5), 345-352 (2010).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Food and Drug Administration. 22, (2015).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> European Medicines Agency. 13, (2014).</li><li>Lopez-Morales, C. 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=Physicochemical+and+biological+characterization+of+a+biosimilar+trastuzumab.">Physicochemical and biological characterization of a biosimilar trastuzumab.</a> Biomed Res Int. 2015, 427235 (2015).</li><li>Jung, 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=Physicochemical+characterization+of+Remsima.">Physicochemical characterization of Remsima.</a> MAbs. 6 (5), 1163-1177 (2014).</li><li>Visser, 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=Physicochemical+and+functional+comparability+between+the+proposed+biosimilar+rituximab+GP2013+and+originator+rituximab.">Physicochemical and functional comparability between the proposed biosimilar rituximab GP2013 and originator rituximab.</a> BioDrugs. 27 (5), 495-507 (2013).</li><li>Li, 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=A+comparative+study+of+different+vector+designs+for+the+mammalian+expression+of+recombinant+IgG+antibodies.">A comparative study of different vector designs for the mammalian expression of recombinant IgG antibodies.</a> J Immunol Methods. 318 (1-2), 113-124 (2007).</li><li>Fitzgerald, K. D., Semler, 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=Bridging+IRES+elements+in+mRNAs+to+the+eukaryotic+translation+apparatus.">Bridging IRES elements in mRNAs to the eukaryotic translation apparatus.</a> Biochim Biophys Acta. 1789 (9-10), 518-528 (2009).</li><li>Ho, S. 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=IRES-mediated+Tricistronic+vectors+for+enhancing+generation+of+high+monoclonal+antibody+expressing+CHO+cell+lines.">IRES-mediated Tricistronic vectors for enhancing generation of high monoclonal antibody expressing CHO cell lines.</a> J Biotechnol. 157 (1), 130-139 (2012).</li><li>Dodev, 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=A+tool+kit+for+rapid+cloning+and+expression+of+recombinant+antibodies.">A tool kit for rapid cloning and expression of recombinant antibodies.</a> Sci Rep. 4, 5885 (2014).</li><li>Walsh, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Post-translational+modifications+of+protein+biopharmaceuticals.">Post-translational modifications of protein biopharmaceuticals.</a> Drug Discov Today. 15 (17-18), 773-780 (2010).</li><li>Backliwal, G., 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=Rational+vector+design+and+multi-pathway+modulation+of+HEK+293E+cells+yield+recombinant+antibody+titers+exceeding+1+g/l+by+transient+transfection+under+serum-free+conditions.">Rational vector design and multi-pathway modulation of HEK 293E cells yield recombinant antibody titers exceeding 1 g/l by transient transfection under serum-free conditions.</a> Nucleic Acids Res. 36 (15), 96 (2008).</li><li>Bebbington, C. 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=High-level+expression+of+a+recombinant+antibody+from+myeloma+cells+using+a+glutamine+synthetase+gene+as+an+amplifiable+selectable+marker.">High-level expression of a recombinant antibody from myeloma cells using a glutamine synthetase gene as an amplifiable selectable marker.</a> Biotechnology (N Y). 10 (2), 169-175 (1992).</li><li>Kaufman, R. 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=Coamplification+and+coexpression+of+human+tissue-type+plasminogen+activator+and+murine+dihydrofolate+reductase+sequences+in+Chinese+hamster+ovary+cells.">Coamplification and coexpression of human tissue-type plasminogen activator and murine dihydrofolate reductase sequences in Chinese hamster ovary cells.</a> Mol Cell Biol. 5 (7), 1750-1759 (1985).</li><li>Dalton, A. C., Barton, W. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Over-expression+of+secreted+proteins+from+mammalian+cell+lines.">Over-expression of secreted proteins from mammalian cell lines.</a> Protein Sci. 23 (5), 517-525 (2014).</li><li>Pham, P. 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=Transient+gene+expression+in+HEK293+cells:+peptone+addition+posttransfection+improves+recombinant+protein+synthesis.">Transient gene expression in HEK293 cells: peptone addition posttransfection improves recombinant protein synthesis.</a> Biotechnol Bioeng. 90 (3), 332-344 (2005).</li><li>Pham, P. 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=Large-scale+transient+transfection+of+serum-free+suspension-growing+HEK293+EBNA1+cells:+peptone+additives+improve+cell+growth+and+transfection+efficiency.">Large-scale transient transfection of serum-free suspension-growing HEK293 EBNA1 cells: peptone additives improve cell growth and transfection efficiency.</a> Biotechnol Bioeng. 84 (3), 332-342 (2003).</li><li>Yang, W. 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=Addition+of+valproic+acid+to+CHO+cell+fed-batch+cultures+improves+monoclonal+antibody+titers.">Addition of valproic acid to CHO cell fed-batch cultures improves monoclonal antibody titers.</a> Molecular Biotechnology. 56 (5), 421-428 (2014).</li><li>Backliwal, G., 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=Valproic+acid:+a+viable+alternative+to+sodium+butyrate+for+enhancing+protein+expression+in+mammalian+cell+cultures.">Valproic acid: a viable alternative to sodium butyrate for enhancing protein expression in mammalian cell cultures.</a> Biotechnol Bioeng. 101 (1), 182-189 (2008).</li><li>Jiang, Z., Sharfstein, S. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sodium+butyrate+stimulates+monoclonal+antibody+over-expression+in+CHO+cells+by+improving+gene+accessibility.">Sodium butyrate stimulates monoclonal antibody over-expression in CHO cells by improving gene accessibility.</a> Biotechnol Bioeng. 100 (1), 189-194 (2008).</li><li>Jordan, M., Wurm, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transfection+of+adherent+and+suspended+cells+by+calcium+phosphate.">Transfection of adherent and suspended cells by calcium phosphate.</a> Methods. 33 (2), 136-143 (2004).</li></ol>

This protocol details the transfection, stable expression and purification of a therapeutic antibody in HEK-293 cells. Stable expression of antibody genes is the first step in generating an antibody-producing cell line for the development and manufacture of a therapeutic antibody. While Chinese hamster ovary (CHO) cells remain the expression platform of choice for therapeutic proteins, the HEK-293 cell line is gaining prominence with the realization that proteins produced in these cells are a closer match to naturally oc...

The success of therapeutic antibodies continues to drive substantial investment into antibody development as a wave of next generation therapeutics begins. The antibody market is expected to be reshaped by antibody fragments 1, antibody-drug conjugates 2, bispecific antibodies 3 and engineered antibodies with favorable properties 4. Another class gaining pharmaceutical interest are biosimilars. Biosimilar antibodies are &#39;highly similar&#39; replicate products of a therapeutic antibody that has already received regulatory approval. A proposed biosimilar must be comparable with the originator antibody with respect to its structure, function, animal toxicity, clinical safety and effectiveness, human pharmacokinetics (PK), pharmacodynamics (PD) and immunogenicity 5,6.
The approval rates of biosimilar antibodies have been slow due to the strict constraints on the final quality of the product. The exact manufacturing processes such as specific cell lines and culturing conditions through to the final processing steps can remain proprietary. What is more, the manufacturing of antibodies inherently involves a degree of variability which can add to the challenge of producing a highly similar product. A comprehensive physiochemical and biophysical characterization and comparison is quite difficult, yet a number of studies demonstrating the characteristics of biosimilar antibodies are emerging in the literature 7,8,9.
Generating a therapeutic antibody begins with transfection of mammalian host cells with a vector carrying the genes for the respective antibody. Vector design, cell line and culture conditions are key considerations for setting up the expression system.
The DNA sequences of antibodies can be sourced from Drug Bank (www.drugbank.ca), IMGT (www.igmt.org) or research publications including patents. For example, the sequence of trastuzumab is available through Drug Bank (DB ID: DB00072). The amino acid sequence of the variable regions can undergo gene design and optimization for synthesis in the desired host species. It is important for a biosimilar antibody that no modification is made to the amino acid sequence. Once synthesized, antibody genes can be subcloned into the appropriate vector of choice.
Human IgG antibodies consist of two identical heavy chains and two identical light chains. Tightly regulated expression of both chains is essential for optimal production of heterologous IgG protein in mammalian cells 10. Intra- as well as inter-chain disulfide bonds have to be formed and a number of post-translational modifications have to be introduced during protein biosynthesis. A number of vectors are available that have been designed specifically to express antibody genes (refer to Table of Materials). These antibody-specific vectors usually express the constant regions for both heavy and light chains so only the variable regions of each chain require cloning.
Transfection of cells with two independent constructs (co-transfection) is the most common approach for delivering heavy and light chain-encoding genes. That is, each gene is driven by its own promoter and transcribed as separate antibody chains before being assembled in the endoplasmic reticulum. On the other hand, multi-cistronic vectors have internal ribosome entry site (IRES) elements incorporated that allow expression of multiple genes as a single mRNA transcript with translation permitted from internal regions of the mRNA 11. In this instance, the heavy and light chain-encoding genes are coupled in an arrangement to achieve co-expression of both antibody chains 10,12.
While transiently transfected cells yield sufficient protein to perform a limited number of experiments, stably transfected cell lines that have undergone selection for genome integration can deliver higher yields. Higher protein amounts allow for assay development relating to in vitro characterization and can provide an indication of antibody quality in consideration for downstream applications such as clonal cell line and lead candidate selection.
The goal of this article is to describe the stable expression and purification of a therapeutic antibody produced in a mammalian expression system. Indeed, this method can be applied to the expression of a biosimilar antibody. The method can be used for the initial characterization of antibodies before proceeding on to the critical, albeit time-consuming steps of identifying a desirable clone for larger scale manufacturing. Moreover, this method can be used to express other proteins and not just antibodies.
The following detailed protocol describes the expression of therapeutic antibody trastuzumab. This consists of preparation of vector DNA followed by stable transfection in HEK-293 cell line and purification of antibody protein by an automated chromatographic method.

<table border="0" cellpadding="0" cellspacing="0" width="1730">
	<colgroup>
		<col />
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:348px;">pFUSE vector series</td>
			<td style="width:189px;">N/A</td>
			<td style="width:191px;">InvivoGen</td>
			<td style="width:1003px;">Heavy and light antibody genes expressed in separate vectors that require co-transfection.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">mAbXpress vector series</td>
			<td>N/A</td>
			<td>ACYTE Biotech Pty Ltd.</td>
			<td>Heavy and light antibody genes expressed in separate vectors that require co-transfection. Refer to: Jones, M. L. et al. A method for rapid, ligation-independent reformatting of recombinant monoclonal antibodies. J Immunol Methods. 354 (1-2), 85-90, doi:10.1016/j.jim.2010.02.001, (2010).</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">pVITRO1 vector</td>
			<td>N/A</td>
			<td>N/A</td>
			<td>Heavy and light antibody genes are each driven by a separate promoter in a single vector.&#160; Refer to: Dodev, T. S. et al. A tool kit for rapid cloning and expression of recombinant antibodies. Sci Rep. 4 5885, doi:10.1038/srep05885, (2014).</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">GS vector series</td>
			<td>N/A</td>
			<td>Lonza</td>
			<td>Multi-cistronic vector with heavy and light antibody genes co-expressed and translated as single transcript.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Multi-cistronic vector series 1</td>
			<td>N/A</td>
			<td>N/A</td>
			<td>Multi-cistronic vector with heavy and light antibody genes co-expressed and translated as single transcript. Refer to: Li, J. et al. A comparative study of different vector designs for the mammalian expression of recombinant IgG antibodies. J Immunol Methods. 318 (1-2), 113-124, doi:10.1016/j.jim.2006.10.010, (2007).</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Multi-cistronic vector series 2</td>
			<td>N/A</td>
			<td>N/A</td>
			<td>Multi-cistronic vector with heavy and light antibody genes co-expressed and translated as single transcript. Refer to: Ho, S. C. et al. IRES-mediated Tricistronic vectors for enhancing generation of high monoclonal antibody expressing CHO cell lines. J Biotechnol. 157 (1), 130-139, doi:10.1016/j.jbiotec.2011.09.023, (2012).</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">pVITRO1-Trastuzumab-IgG1/&#954;</td>
			<td>61883</td>
			<td>Addgene</td>
			<td>Mammalian expression vector containing trastuzumab antibody genes with hygromycin resistance gene; pVITRO1-Trastuzumab-IgG1/&#954; was a gift from Andrew Beavil.</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Fast-Media Hygro Agar</td>
			<td>fas-hg-s</td>
			<td>Jomar Life Research</td>
			<td>Used to prepare low salt LB agar containing 75 &#181;g/ml hygromycin.</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Fast-Media Hygro TB</td>
			<td>fas-hg-l</td>
			<td>Jomar Life Research</td>
			<td>Used to prepare low salt TB broth containing 75 &#181;g/ml hygromycin.&#160;</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Glycerol, BioXtra, &#8805;99%</td>
			<td>G6279</td>
			<td>Sigma-Aldrich</td>
			<td>Prepare to 80% with water and autoclave. Store at room temperature.</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Jestar 2.0/LFU Plasmid Maxi Kit</td>
			<td>G221020</td>
			<td>Astral Scientific</td>
			<td>Plasmid Maxi Prep Kit; elute or resuspend DNA in water (pH 7.0-8.5).</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">FreeStyle 293-F Cells</td>
			<td>R790-07</td>
			<td>Life Technologies</td>
			<td>HEK-293 cell line adapted to suspension culture in serum-free media.</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">FreeStyle 293 Expression Medium</td>
			<td>12338-018</td>
			<td>Life Technologies</td>
			<td>Serum-free media specially formulated for maintaing 293-F cell line and high protein expression.</td>
		</tr>
		<tr height="24">
			<td height="24" style="height:24px;">Kolliphor P188</td>
			<td>K4894</td>
			<td>Sigma-Aldrich</td>
			<td>Non-ionic surfactant; pluronic F-68; prepare to 10% in water and filter-sterilize using 0.22 &#956;m filter. Store at 4oC.</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">DMEM, high glucose&#160;</td>
			<td>11995-065</td>
			<td>Life Technologies</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Heat-Inactivated Foetal Bovine Serum</td>
			<td>10082-147</td>
			<td>Life Technologies</td>
			<td></td>
		</tr>
		<tr height="24">
			<td height="24" style="height:24px;width:348px;">Polyethylenimine, Linear, MW 25,000&#160;</td>
			<td>23966</td>
			<td>Polysciences, Inc.</td>
			<td>Prepare to 1 mg/ml in water. Adjust to pH 7.0 with 1 M HCl (solution becomes clear) and filter-sterilize using 0.22 &#956;m filter. Store at -80oC until use.</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">OptiPro SFM</td>
			<td>12309-050</td>
			<td>Life Technologies</td>
			<td>Transfection formulated serum-free media</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Hygromycin B Solution</td>
			<td>ant-hg-1</td>
			<td>Jomar Life Research</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Dimethylsulphoxide (DMSO)</td>
			<td>AJA2225</td>
			<td>Thermo Fisher Scientific</td>
			<td></td>
		</tr>
		<tr height="24">
			<td height="24" style="height:24px;">Tryptone (casein peptone)</td>
			<td>LP0042B</td>
			<td>Thermo Fisher Scientific</td>
			<td>Prepare to 20% in PBS and filter-sterilize using 0.22 &#956;m filter. Store at 4oC.&#160;</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Phosphate Buffered Saline (PBS) Tablets, pH 7.4, 100 ml</td>
			<td>09-2051-100</td>
			<td>Astral Scientific</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">HiTrap Protein A High Performance, 1 x 5 ml column</td>
			<td>GE17-0403-01</td>
			<td>Sigma-Aldrich</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">AKTApurifier 100</td>
			<td>28406266</td>
			<td>GE Healthcare</td>
			<td>Automated FPLC system, which can include a P-960 sample pump and Frac-920 fraction collector.</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Glycine-HCl</td>
			<td>G2879</td>
			<td>Sigma-Aldrich</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Citric Acid, monohydrate</td>
			<td>BIOC2123</td>
			<td>Astral Scientific</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Sodium Citrate, trisodium salt dihydrate&#160;</td>
			<td>BIOCB0035</td>
			<td>Astral Scientific</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">1 M Tris-HCl solution pH 9.0</td>
			<td>BIOSD8146</td>
			<td>Astral Scientific</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Amicon Ultra Centrifugal Filters (30 MWCO)</td>
			<td>UFC803008/UFC903008</td>
			<td>Merck Millipore</td>
			<td>Used to buffer exchange and concentrate purified protein.</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Pierce Bicinchoninic Acid (BCA) Assay Kit</td>
			<td>23227</td>
			<td>Thermo Fisher Scientific</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">BLItz System</td>
			<td>45-5000</td>
			<td>fort&#233;BIO</td>
			<td>Instrument used for bio-layer interferometry (BLI) measurements.</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Protein A biosensors</td>
			<td>18-5010</td>
			<td>fort&#233;BIO</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Acrylamide/Bisacrylamide (37.5:1), 40% solution</td>
			<td>786-502</td>
			<td>Astral Scientific</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Ammonium Persulfate (APS)</td>
			<td>AM0486</td>
			<td>Astral Scientific</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">TEMED</td>
			<td>AM0761</td>
			<td>Astral Scientific</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Coomassie Brilliant Blue R-250</td>
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laboratory scale production and purification of a therapeutic antibody

Ensuring the successful production of a therapeutic antibody begins early on in the development process. The first stage is vector expression of the antibody genes followed by stable transfection into a suitable cell line. The stable clones are subjected to screening in order to select those clones with desired production and growth characteristics. This is a critical albeit time-consuming step in the process. This protocol considers vector selection and sourcing of antibody sequences for the expression of a therapeutic antibody. The methods describe preparation of vector DNA for stable transfection of a suspension variant of human embryonic kidney 293 (HEK-293) cell line, using polyethylenimine (PEI). The cells are transfected as adherent cells in serum-containing media to maximize transfection efficiency, and afterwards adapted to serum-free conditions. Large scale production, setup as batch overgrow cultures is used to yield antibody protein that is purified by affinity chromatography using an automated fast protein liquid chromatography (FPLC) instrument. The antibody yields produced by this method can provide sufficient protein to begin initial characterization of the antibody. This may include in vitro assay development or physicochemical characterization to aid in the time-consuming task of clonal screening for lead candidates. This method can be transferable to the development of an expression system for the production of biosimilar antibodies.

Stable production of trastuzumab by transfected HEK-293 cells was confirmed using bio-layer interferometry (BLI) as presented in Figure 1. An IgG standard curve was generated by measuring the binding rate between an IgG antibody standard and Protein A biosensor (Figure 1A). The crude supernatant sample was similarly measured, then its concentration interpolated from the standard curve (Figure 1B). The supernatant concentration was measure...

Watch this Scientific Journal Video about Laboratory Scale Production and Purification of a Therapeutic Antibody at JoVE.com

Laboratory Scale Production and Purification of a Therapeutic Antibody

This protocol describes the production of a therapeutic antibody in a mammalian expression system. The methods described include preparation of vector DNA, stable transfection and serum-free adaptation of a human embryonic kidney 293 cell line, set up of large scale cultures and purification using affinity chromatography.

Ensuring the successful production of a therapeutic antibody begins early on in the development process. The first stage is vector expression of the ...

The overall goal of this method is to develop a high-yielding serum free expression system for the lab scale production of a therapeutic antibody. This method can address key considerations in the design of an antibody expression system such as producing a stable cell line, the addition of supplements, and optimizing purification strategies. The main advantage of this technique is that producing a stable cell line adapted to serum media will yield robust and reproducible quantities of therapeutic antibody.To begin, culture HEK-293 cells according to standard protocols in serum-free medium supplemented with 0.1%nonionic surfactant, in Erlenmeyer flasks. Incubate the cells at 37 degrees Celsius and 5%carbon dioxide at 120 rotations per minute. Maintain the culture at two times 10 to the fifth cells per milliliter and subculture every fourth day.On the day prior to transpection, seed HEK-293 cells at three times 10 to the fifth cells per milliliter in the wells of a 12 vial plate in two milliliters of DMEM with 10%heat inactivated FBS. On the day of transpection, check that the cells have reached 80 to 90%confluency. Dilute 1.25 micrograms of vector DNA per well, in 300 microliters of transpection medium.Then use 300 microliters of transpection medium to dilute 2.5 microliters of one milligram per milliliter of polyethylenimine, or PEI solution, per well. Incubate both solutions at room temperature for 5 minutes. Next, add the diluted DNA to the diluted PEI.Gently mix, and incubate the solution at room temperature for fifteen minutes. Then add 50 microliters of the DNA PEI mixture drop wise to each well of the plate. Gently rock the plate to distribute the transpection mixture then incubate the plate at 37 degrees Celsius and 5%carbon dioxide for 24 hours.The following day, add 50 micrograms per milliliter of hygromycin B per well and return the plate to the incubator for 10 days. Following transpection, successful stable transfectants will remain viable and adherent. To carry out serum-free adaptation, replace the medium in the wells with 1/4 the volume of serum-free medium and 3/4 the volume of DMEM with 10%FBS.Incubate the cultures for four days. Then replace the medium with half the volume of serum-free medium and half the volume of DMEM with 10%FBS. And incubate for an additional four days.Now, replace the medium with 3/4 the volume of serum-free medium and 1/4 the volume DMEM supplemented with 10%FBS. And incubate for an additional four days. Finally, replace the medium with serum-free medium supplemented with 0.1%of a nonionic surfactant and incubate for four more days.Following the successful adaptation of stable cells, use a pipette to gently mix the suspension cultures in a 12 well plate and pool the cells in a separate tube. With the hemocytometer, enumerate the pooled cells and seed the cells in 30 milliliters of serum-free medium in a flask at two times 10 to the fifth cells per milliliter. Culture the cells at 37 degrees Celsius and 5%carbon dioxide at 120 rotations per minute.Subculture the cells and expand every fourth day. To compare antibody yields from unsupplemented and nutrient-supplemented cultures, seed cells at two times 10 to fifth cells per milliliter in 100 milliliters of serum-free medium in two flasks. Incubate the cells at 37 degrees Celsius and 5%carbon dioxide at 120 rotations per minute for 24 hours.To the nutrient-supplemented culture, add tryptone to a final concentration of 0.5%then use serum-free medium to equalize the volume of the unsupplemented culture. Incubate the cells for an additional seven days. From the eighth day of culturing forward, count the cells daily using a hemocytometer to monitor cell viability.Once the cell viability reaches less than 80%harvest the culture by centrifugation at 3000 times G for 15 minutes. Then filter sterilized a supernatant through a 0.22 micrometer filter. Store the supernatants at four degrees Celsius in the short term or freeze at negative 20 degrees Celsius long term.After preparing buffers and initializing the FPLC system according to the text protocol, use the method editor to set up the run steps as follows. Equilibrate the system with five column volumes, or CV of binding buffer. Load the sample onto the column and collect the sample flow through.And then use five CV of binding buffer to wash the system. Use five CV of elution buffer to elute the column via isocratic fractionation. And collect the purified antibody samples as fractions using the fraction collector.Finally, equilibrate the system with five CV of binding buffer and collect the flow through into a waste container. Once the method set up is complete, specify the volume of conditioned medium to be a applied to the column and save the method. Next, submerge the sample pump tubing into the vessel containing the conditioned medium.Then prepare a separate container to collect sample flow through via the specified outlet tubing. Insert collection tubes in the fraction collector and add neutralization buffer to each collection tube. In the system control module of the software, open the method to be used.Then click start to initiate the run. When the purification is complete, in the evaluation module, check the resulting chromatogram. Combine all the protein containing fractions into a tube and then use PBS and a centrifugal filter device with a 30 kilodalton cut-off to concentrate the sample and carry out buffer exchange.Finally, use the BCA assay to measure the antibody concentration according to the manufacturer's instructions. Stable production of trastuzumab bar transfected HEK-293 cells was confirmed using biolayer interferometry as presented in this figure. An IGG standard curve was generated by measuring the binding rate between an IGG antibody standard and a protein A biosensor.The crude supernatant sample was similarly measured and its concentration interpolated at 25 micrograms per milliliter from the standard curve. As shown in this chromatogram, measurement of PH conductivity and system pressure are monitored during sample loading, column washing, and finally, elution of the bound protein. Three buffers were tested for optimal binding of trastuzumab to the column and washing to maximize elution yield.Scouting the optimal elution PH and buffer revealed that the antibody eluded more efficiently at a lower PH using 0.1 molar glycine HCL or citric acid. In addition, elution peaks with 0.1 molar glycine HCL appeared less broadened when compared with 0.1 molar citric acid at a similar PH.The purification chromatograms of batch overgrow cultures are shown here. The tryptone supplemented culture yielded 3.8 milligrams and the unsupplemented culture 1.7 milligrams of trastuzumab as measured following buffer exchange and concentration.Finally, this STS page shows that trastuzumab grown in unsupplemented and tryptone supplemented conditions results in similar antibody profiles under non-reducing and reducing conditions. Once optimized, this process of producing a stable cell line that is adapted to serum-free culture and harvesting practical quantities of antibody can be done in under six weeks if it is performed without mishap. While attempting this procedure, it's important to critically monitor the cells during the adaption process.The four day turnover is a recommendation and if cells are struggling at a particular adaption step, then subculture at the previous adaption step before proceeding. Following this procedure, other methods such as size exclusion HPLC, ELISA, and western blotting can be performed in order to further characterize and confirm the antibody product. After watching this video, you should have a good understanding of how to produce a stable cell line and adapt it to serum-free conditions in pursuit of developing a high-yielding expression system for the lab scale production of antibody protein.

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