Name: in vitro methods for comparing target binding and cdc induction between therapeutic antibodies: applications in biosimilarity analysis
Uploaded: 2017-05-04T13:00:00
Description: Watch this Scientific Journal Video about In Vitro Methods for Comparing Target Binding and CDC Induction Between Therapeutic Antibodies: Applications in Biosimilarity Analysis at JoVE.com

The authors have no acknowledgements.

1. Evaluation of Target Binding by Flow Cytometry
<ol>
	<li>Preparation of biological materials and reagents
	<ol>
		<li>Make 500 mL of RPMI culture medium supplemented with 10% heat-inactivated fetal bovine serum (H-IFBS).</li>
		<li>Culture Daudi Burkitt&#39;s Lymphoma (Daudi) cells and Daudi GFP+ cells using RPMI and 75-cm2 culture flasks. Maintain the cultures at 37 &#176;C in a 5% CO2 humidified atmosphere until they reach 6 - 9 x 105 cells/mL.</li>
		<l...

<ol>
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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=The+Biological+Activity+of+Human+CD20+Monoclonal+Antibodies+Is+Linked+to+Unique+Epitopes+on+CD20.">The Biological Activity of Human CD20 Monoclonal Antibodies Is Linked to Unique Epitopes on CD20.</a> J Immunol. 177 (1), 362-371 (2006).</li><li>Miranda-Hernandez, M. 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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=Engineered+antibody+Fc+variants+with+enhanced+effector+function.">Engineered antibody Fc variants with enhanced effector function.</a> Proc Natl Acad Sci U S A. 103 (11), 4005-4010 (2006).</li><li>Winiarska, 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=Statins+impair+antitumor+effects+of+rituximab+by+inducing+conformational+changes+of+CD20.">Statins impair antitumor effects of rituximab by inducing conformational changes of CD20.</a> PLoS medicine. 5 (3), e64 (2008).</li><li>Zhou, X., Hu, W., Qin, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+role+of+complement+in+the+mechanism+of+action+of+rituximab+for+B-cell+lymphoma:+implications+for+therapy.">The role of complement in the mechanism of action of rituximab for B-cell lymphoma: implications for therapy.</a> Oncologist. 13 (9), 954-966 (2008).</li><li>Hayashi, 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=Gemcitabine+enhances+rituximab-mediated+complement-dependent+cytotoxicity+to+B+cell+lymphoma+by+CD20+upregulation.">Gemcitabine enhances rituximab-mediated complement-dependent cytotoxicity to B cell lymphoma by CD20 upregulation.</a> Cancer Sci. 107 (5), 682-689 (2016).</li><li>Mossner, E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Increasing+the+efficacy+of+CD20+antibody+therapy+through+the+engineering+of+a+new+type+II+anti-CD20+antibody+with+enhanced+direct+and+immune+effector+cell-mediated+B-cell+cytotoxicity.">Increasing the efficacy of CD20 antibody therapy through the engineering of a new type II anti-CD20 antibody with enhanced direct and immune effector cell-mediated B-cell cytotoxicity.</a> Blood. 115 (22), 4393-4402 (2010).</li><li>Lapalombella, 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=A+novel+Raji-Burkitt's+lymphoma+model+for+preclinical+and+mechanistic+evaluation+of+CD52-targeted+immunotherapeutic+agents.">A novel Raji-Burkitt's lymphoma model for preclinical and mechanistic evaluation of CD52-targeted immunotherapeutic agents.</a> Clin Cancer Res. 14 (2), 569-578 (2008).</li><li>Mitoma, 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=Mechanisms+for+cytotoxic+effects+of+anti-tumor+necrosis+factor+agents+on+transmembrane+tumor+necrosis+factor+alpha-expressing+cells:+comparison+among+infliximab,+etanercept,+and+adalimumab.">Mechanisms for cytotoxic effects of anti-tumor necrosis factor agents on transmembrane tumor necrosis factor alpha-expressing cells: comparison among infliximab, etanercept, and adalimumab.</a> Arthritis Rheum. 58 (5), 1248-1257 (2008).</li><li>Kaymakcalan, Z., 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=Comparisons+of+affinities,+avidities,+and+complement+activation+of+adalimumab,+infliximab,+and+etanercept+in+binding+to+soluble+and+membrane+tumor+necrosis+factor.">Comparisons of affinities, avidities, and complement activation of adalimumab, infliximab, and etanercept in binding to soluble and membrane tumor necrosis factor.</a> Clin Immunol. 131 (2), 308-316 (2009).</li><li>Zent, C. 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=Direct+and+complement+dependent+cytotoxicity+in+CLL+cells+from+patients+with+high-risk+early-intermediate+stage+chronic+lymphocytic+leukemia+(CLL)+treated+with+alemtuzumab+and+rituximab.">Direct and complement dependent cytotoxicity in CLL cells from patients with high-risk early-intermediate stage chronic lymphocytic leukemia (CLL) treated with alemtuzumab and rituximab.</a> Leuk Res. 32 (12), 1849-1856 (2008).</li><li>Goswami, M. T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regulation+of+complement-dependent+cytotoxicity+by+TGF-beta-induced+epithelial-mesenchymal+transition.">Regulation of complement-dependent cytotoxicity by TGF-beta-induced epithelial-mesenchymal transition.</a> Oncogene. 35 (15), 1888-1898 (2016).</li><li>Wang, 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=Induction+of+anti-EGFR+immune+response+with+mimotopes+identified+from+a+phage+display+peptide+library+by+panitumumab.">Induction of anti-EGFR immune response with mimotopes identified from a phage display peptide library by panitumumab.</a> Oncotarget. , (2016).</li><li>Ueda, N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+cytotoxic+effects+of+certolizumab+pegol+and+golimumab+mediated+by+transmembrane+tumor+necrosis+factor+alpha.">The cytotoxic effects of certolizumab pegol and golimumab mediated by transmembrane tumor necrosis factor alpha.</a> Inflamm Bowel Dis. 19 (6), 1224-1231 (2013).</li><li>Nesbitt, 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=Mechanism+of+action+of+certolizumab+pegol+(CDP870):+in+vitro+comparison+with+other+anti-tumor+necrosis+factor+alpha+agents.">Mechanism of action of certolizumab pegol (CDP870): in vitro comparison with other anti-tumor necrosis factor alpha agents.</a> Inflamm Bowel Dis. 13 (11), 1323-1332 (2007).</li><li>Teeling, J. 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The patent expiration of a therapeutic mAb is promoting the development of biosimilars. Thus, there is a need for simple methods that can identify differences in clinically relevant activities of these products. CD20+ cultured cells were employed for the evaluation of two key functional characteristics of rituximab: target binding and CDC induction. The former activity requires the recognition of CD20 by the Fab region of the mAb, while the latter depends mainly on the interaction of the Fc region with its com...

Therapeutic antibodies are recombinant monoclonal antibodies (mAbs) developed for the treatment of different pathologies, including cancers, autoimmune and chronic diseases, neurologic disorders, and others1. Currently, the FDA has granted approval to more than 40 therapeutic mAbs, and more are expected to reach the market in the following years.
Rituximab is a high-affinity chimeric monoclonal IgG1 antibody approved for the treatment of CD20+ B-cell non-Hodgkin&#39;s lymphoma (NHL), CD20+ follicular NHL, chronic lymphocytic leukemia, and rheumatoid arthritis2,3. The recognition of CD20, which is overexpressed in B cells, by rituximab induces apoptosis; complement activation; and antibody-dependent cell mediated cytotoxicity (ADCC)3. The patents of this drug expired in Europe and in the U.S. in 2013 and 2016, respectively. Thus, pharmaceutical companies worldwide are developing rituximab biosimilars. As in any other drug for human consumption, biosimilars require approval from regulatory agencies. International guidelines indicate that for mAbs, biosimilarity should be demonstrated by comparing the physicochemical characteristics, pharmacokinetics, efficacy, and safety of the new and reference products4.
Accordingly, the methodologies used in such comparisons must assess the structural and functional characteristics of the mAbs, especially those with clinical relevance. To that end, in vitro assays show several advantages over in vivo experiments (reviewed in Chapman et al.)5: i) in vitro studies are more sensitive to differences between the proposed biosimilar and the reference product; ii) in vivo studies must be performed in relevant species, which for many mAbs are non-human primates; and iii) since the mechanism of action, the preclinical toxicology, and the clinical effects of the reference product are well known, in vivo studies with biosimilars may not provide additional useful information. Accordingly, the European Union&#39;s Guidance for biosimilars allows candidates to enter clinical trials based on robust in vitro data alone6.
Here, we present two fast, economic, and simple assays that evaluate the biological activity of rituximab using CD20+ cultured cells. These assays can be included as part of the comparability exercise for rituximab biosimilar candidates.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>RPMI-1640 medium</td>
			<td>ATCC</td>
			<td>30-2001</td>
			<td>Modify the culture depending on the cell line</td>
		</tr>
		<tr>
			<td>Trypan Blue solution</td>
			<td>Sigma</td>
			<td>T8154</td>
			<td>0.4%, liquid, sterile-filtered, suitable for cell culture</td>
		</tr>
		<tr>
			<td>Daudi Burkitt&#39;s Lymphoma Cells</td>
			<td>ATCC</td>
			<td>CCL-213</td>
			<td>You can modify the cell line depending on the antibody of interest</td>
		</tr>
		<tr>
			<td>Fetal bovine serum(FBS)</td>
			<td>GIBCO</td>
			<td>16000-044</td>
			<td>You can modify the source of serum depending of requirements of the cell line</td>
		</tr>
		<tr>
			<td>Normal Human Serum Complement</td>
			<td>Quidel</td>
			<td>A113</td>
			<td>It is therefore appropriate for use in biocompatibility experiments including drug development, biomaterials testing and other applications</td>
		</tr>
		<tr>
			<td>7AA-D</td>
			<td>BDPharmigen</td>
			<td>559925</td>
			<td>You can use broad range of color options, compatible with most instrument configurations for to analyze viability.</td>
		</tr>
		<tr>
			<td>PECy5 Mouse Anti-human IgG</td>
			<td>BDPharmigen</td>
			<td>551497</td>
			<td>Change fluorochrome depending on the filter and laser of your flow cytometer.</td>
		</tr>
		<tr>
			<td>Human IgG Isotype Control</td>
			<td>ThermoFisher Scientific</td>
			<td>07-7102</td>
			<td>Change depending to mAb</td>
		</tr>
		<tr>
			<td>BDCytofix</td>
			<td>BDPharmigen</td>
			<td>554655</td>
			<td>Flow Cytometry Fixation Buffer (1-4% formaldehyde or paraformaldehyde )</td>
		</tr>
		<tr>
			<td>PBS pH 7.4 10X (Phosphate buffer saline)</td>
			<td>GIBCO</td>
			<td>70011-044</td>
			<td>Phosphatebuffer without Ca2+/Mg2+ [137 mM NaCl, 2.7 mM KCl, 8 mM Na2HPO4, 1.46 mM KH2PO4] and endotoxin free.</td>
		</tr>
		<tr>
			<td>Cell culture plates 96 well, V-bottom</td>
			<td>Corning</td>
			<td>29442-068</td>
			<td>12 x 75 mm round bottom test tubes or 96-well V- or U- bottom microtiter plates</td>
		</tr>
		<tr>
			<td>MabThera (Rituximab)</td>
			<td>Roche</td>
			<td>&#8212;</td>
			<td>Reference product</td>
		</tr>
		<tr>
			<td>Rituximab</td>
			<td>Indian</td>
			<td>&#8212;</td>
			<td>Biosimilar product</td>
		</tr>
		<tr>
			<td>15- or 50-mL conical centrifuge tubes</td>
			<td>Corning</td>
			<td>430290 or 430052</td>
			<td>&#8212;</td>
		</tr>
		<tr>
			<td>Pipette Tips</td>
			<td>Eppendorf</td>
			<td>&#8212;</td>
			<td>Multiple volume configurations are necessary</td>
		</tr>
		<tr>
			<td>Pipettes</td>
			<td>Eppendorf</td>
			<td>&#8212;</td>
			<td>Adjustable-volume pipettes are necessary</td>
		</tr>
		<tr>
			<td>Centrifuge 5430/ 5430R model</td>
			<td>Eppendorf</td>
			<td>&#8212;</td>
			<td>Refrigerated variable-speed centrifuge (4 to 25 &#176; C) with speeds ranging from 10 to 30,130 &#215; g</td>
		</tr>
		<tr>
			<td>Flow cytometer</td>
			<td>BD Dickinson</td>
			<td>&#8212;</td>
			<td>BD FACSAria III or other flow cytometer</td>
		</tr>
		<tr>
			<td>Olympus optical and light microscope</td>
			<td>Olympus</td>
			<td>&#8212;</td>
			<td>To quantify and evaluate cell growth</td>
		</tr>
		<tr>
			<td>Incubator</td>
			<td>SANYO</td>
			<td>&#8212;</td>
			<td>Incubatorfor temperature andCO2 control to culture cells</td>
		</tr>
		<tr>
			<td>Biological Safety Cabinet</td>
			<td>CHC BIOLUS</td>
			<td>&#8212;</td>
			<td>Biological safety cabinet that is used to protect the researcher, product and environment.</td>
		</tr>
	</tbody>
</table>

in vitro methods for comparing target binding and cdc induction between therapeutic antibodies: applications in biosimilarity analysis

Therapeutic monoclonal antibodies (mAbs) are relevant to the treatment of different pathologies, including cancers. The development of biosimilar mAbs by pharmaceutical companies is a market opportunity, but it is also a strategy to increase drug accessibility and reduce therapy-associated costs. The protocols detailed here describe the evaluation of target binding and CDC induction by rituximab in Daudi cells. These two functions require different structural regions of the antibody and are relevant to the clinical effect induced by rituximab. The protocols allow the side-to-side comparison of a reference rituximab and a marketed rituximab biosimilar. The evaluated products showed differences both in target binding and CDC induction, suggesting that there are underlying physicochemical differences and highlighting the need to analyze the impact of those differences in the clinical setting. The methods reported here constitute simple and inexpensive in vitro models for the evaluation of the activity of rituximab biosimilars. Thus, they can be useful during biosimilar development, as well as for quality control in biosimilar production. Furthermore, the presented methods can be extrapolated to other therapeutic mAbs.

Using the protocols described above, target binding and the CDC induction of reference rituximab were compared in parallel with those of a biosimilar rituximab produced and commercially available in Asia.
In Daudi cells, both mAbs bound CD20 in a concentration-dependent manner (Figure 1D). Non-linear regressions of binding data displayed an r2 of 0.978 and 0.848 for reference and biosimilar rituximab,...

Watch this Scientific Journal Video about In Vitro Methods for Comparing Target Binding and CDC Induction Between Therapeutic Antibodies: Applications in Biosimilarity Analysis at JoVE.com

In Vitro Methods for Comparing Target Binding and CDC Induction Between Therapeutic Antibodies: Applications in Biosimilarity Analysis

This protocol describes the in vitro comparison of two key functional characteristics of rituximab: target binding and complement-dependent cytotoxicity (CDC) induction. The methods were employed for a side-to-side comparison between reference rituximab and a rituximab biosimilar. These assays can be employed during biosimilar development or as a quality control in their production.

In Vitro Methods for Comparing Target Binding and CDC Induction Between Therapeutic Antibodies: Applications in Biosimilarity Analysis

Therapeutic monoclonal antibodies (mAbs) are relevant to the treatment of different pathologies, including cancers. The development of biosimilar mAbs by ...

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