Research contract Miguel Servet (ISCIII CD14/00032) to (G.N.-G.). Fellowship from the Netherlands Organization for Scientific Research &#8220;Graduate School of Translational Neuroscience Program&#8221; (022005019) to (C.H.).
Grants from the Prinses Beatrix Fonds (Project WAR08-12) and the Association Fran&#231;aise contre les Myopathies to (P.M.-M.); as well as by a Veni Fellowship of the Netherlands Organization for Scientific Research (916.10.148) a fellowship of the Brain Foundation of the Netherlands (FS2008(1)-28) and the Prinses Beatrix Fonds (Project WAR08-12) (to M.L.).
We thank Jozien Jaspers for her help in the B-cell sorting by flow cytometry.

Informed consent was obtained from the participants of the study. The study was approved by the institutional ethics committee.
1. Isolation of Peripheral Blood Mononuclear Cells (PBMCs)
<ol>
	<li>Centrifuge 25 ml&#160;of the participants&#8217; heparinized blood at 900 x g for 15 min, as soon as possible after the blood extraction. If there is less blood, scale down the reagents accordingly. Perform all the next steps in a hood.</li>
	<li>Transfer the serum to a clean tube. It can be used i...

<ol>
	<li>Vrolix, 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=Clonal+heterogeneity+of+thymic+B+cells+from+early-onset+myasthenia+gravis+patients+with+antibodies+against+the+acetylcholine+receptor.">Clonal heterogeneity of thymic B cells from early-onset myasthenia gravis patients with antibodies against the acetylcholine receptor.</a> J Autoimmun. 52, 101-112 (2014).</li><li>Yamashita, M., Katakura, Y., Shirahata, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recent+advances+in+the+generation+of+human+monoclonal+antibody.">Recent advances in the generation of human monoclonal antibody.</a> Cytotechnology. 55 (2-3), 55-60 (2007).</li><li>Pereira, K. M., Dellavance, A., Andrade, L. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+challenge+of+identification+of+autoantibodies+specific+to+systemic+autoimmune+rheumatic+diseases+in+high+throughput+operation:+Proposal+of+reliable+and+feasible+strategies.">The challenge of identification of autoantibodies specific to systemic autoimmune rheumatic diseases in high throughput operation: Proposal of reliable and feasible strategies.</a> Clin Chim Acta. 437, 403-410 (2014).</li><li>Losen, 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=Treatment+of+myasthenia+gravis+by+preventing+acetylcholine+receptor+modulation.">Treatment of myasthenia gravis by preventing acetylcholine receptor modulation.</a> Ann N Y Acad Sci. 1132, 174-179 (2008).</li><li>Smith, 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=Rapid+generation+of+fully+human+monoclonal+antibodies+specific+to+a+vaccinating+antigen.">Rapid generation of fully human monoclonal antibodies specific to a vaccinating antigen.</a> Nat Protoc. 4 (3), 372-384 (2009).</li><li>Fraussen, 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+novel+method+for+making+human+monoclonal+antibodies.">A novel method for making human monoclonal antibodies.</a> J Autoimmun. 35 (2), 130-134 (2010).</li><li>Traggiai, 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=An+efficient+method+to+make+human+monoclonal+antibodies+from+memory+B+cells:+potent+neutralization+of+SARS+coronavirus.">An efficient method to make human monoclonal antibodies from memory B cells: potent neutralization of SARS coronavirus.</a> Nat Med. 10 (8), 871-875 (2004).</li><li>Fraussen, 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=Autoantigen+induced+clonal+expansion+in+immortalized+B+cells+from+the+peripheral+blood+of+multiple+sclerosis+patients.">Autoantigen induced clonal expansion in immortalized B cells from the peripheral blood of multiple sclerosis patients.</a> J Neuroimmunol. 261 (1-2), 98-107 (2013).</li><li>Yamashita, 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=Different+individual+immune+responses+elicited+by+in+vitro+immunization.">Different individual immune responses elicited by in vitro immunization.</a> Cytotechnology. 40 (1-3), 161-165 (2002).</li><li>Hui-Yuen, J., Koganti, S., Bhaduri-McIntosh, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+B+cell+immortalization+for+monoclonal+antibody+production.">Human B cell immortalization for monoclonal antibody production.</a> Methods Mol Biol. 1131, 183-189 (2014).</li><li>Tiller, 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=Efficient+generation+of+monoclonal+antibodies+from+single+human+B+cells+by+single+cell+RT-PCR+and+expression+vector+cloning.">Efficient generation of monoclonal antibodies from single human B cells by single cell RT-PCR and expression vector cloning.</a> J Immunol Methods. 329 (1-2), 112-124 (2008).</li><li>Lanzavecchia, A., Corti, D., Sallusto, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+monoclonal+antibodies+by+immortalization+of+memory+B+cells.">Human monoclonal antibodies by immortalization of memory B cells.</a> Curr Opin Biotechnol. 18 (6), 523-528 (2007).</li><li>Traggiai, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Immortalization+of+human+B+cells:+analysis+of+B+cell+repertoire+and+production+of+human+monoclonal+antibodies.">Immortalization of human B cells: analysis of B cell repertoire and production of human monoclonal antibodies.</a> Methods Mol Biol. 901, 161-170 (2012).</li><li>Strober, W., 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=Monitoring+cell+growth.+Curr+Protoc+Immunol+/+edited+by.">Monitoring cell growth. Curr Protoc Immunol / edited by.</a> John E. Coligan ... [et al.]. Appendix 3, Appendix 3A (2001).</li><li>Ibrahim, S. F., van den Engh, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Flow+cytometry+and+cell+sorting.">Flow cytometry and cell sorting.</a> Adv Biochem Eng Biotechnol. 106, 19-39 (2007).</li><li>Leith, J. T., Padfield, G., Faulkner, L. E., Quinn, P., Michelson, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+feeder+cells+on+the+X-ray+sensitivity+of+human+colon+cancer+cells.">Effects of feeder cells on the X-ray sensitivity of human colon cancer cells.</a> Radiother Oncol. 21 (1), 53-59 (1991).</li><li>Hui-Yuen, J., McAllister, S., Koganti, S., Hill, E., Bhaduri-McIntosh, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Establishment+of+Epstein-Barr+virus+growth-transformed+lymphoblastoid+cell+lines.">Establishment of Epstein-Barr virus growth-transformed lymphoblastoid cell lines.</a> J Vis Exp. (57), 3321 (2011).</li><li>Smith, L. 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=Fluorescence+detection+in+automated+DNA+sequence+analysis.">Fluorescence detection in automated DNA sequence analysis.</a> Nature. 321 (6071), 674-679 (1986).</li></ol>

The authors declare that they have no competing financial interests.

In this manuscript, all the steps for the generation of IgG antibodies from human PBMCs are presented in detail. This protocol includes some advantages over previously published techniques. One of the advantages is that the antibody produced keeps the heavy and light chains corresponding to the original pair in the B cell clone. The identification of IgG antibodies can be done in any type of human donor, and there is no need for exacerbation of the immune response due to vaccination5. The use of the fibroblast...

The goal of this article is to describe in detail a methodology to generate and characterize human IgG monoclonal antibodies obtained from human peripheral blood mononuclear cells (PBMCs).
The interest to study human antibodies has grown in many different fields of research. In particular, many research groups are interested in the pathology caused by auto-antibodies1-3. We have cloned and characterized pathogenic auto-antibodies1. The study of auto-antibodies can help to identify their targets and to develop therapeutic strategies, e.g., using competitor antibodies4. Moreover, the study of human antibodies can also be of interest in other fields of research, i.e., to evaluate the immune response after vaccination5, to characterize the antibody profile of individuals that were exposed and became resistant to specific pathogens6 or to study which antibodies are in the natural repertoire7,12.
Several techniques have been developed to generate recombinant human monoclonal antibodies8-12; most of these use phage display and B-cell immortalization. The use of phage display has been extensively applied for the discovery of new antibodies13. However it has a major disadvantage, namely that the heavy and light chain&#160;pairs of the human immunoglobulin become dissociated in the process. Production of hybridomas with human B cells or EBV transformation overcomes this drawback.
We use infection of thymic B cells with EBV in combination with polyclonal B cell stimulation via Toll-like receptor 9 (TLR-9)6,12.
In this paper, we describe in detail the technology that we use for the development of IgG human antibodies, with a complete overview of all the steps from PBMC isolation to the in vitro antibody generation. This protocol can be used for the analysis of any type of human IgG profile. In our laboratory, B cells producing IgG antibodies have been successfully separated from the rest of PBMCs after sorting. Fifty sorted B cells8 can then be plated in multi-well plates and immortalized by EBV and TLR-9 activation, for the clonal expansion of single B cells. As feeder cells, fibroblasts from human embryonic lung tissue have been used, cell line wi38, which facilitates the visualization of the immortalized B cells. From these B cells, the sequences of the heavy and light chains of the immunoglobulin can be obtained by PCR, and the antibodies&#39; genes cloned in immunoglobulin G expression vectors and produced in vitro. Using this technique, single antibodies with exactly the same antibody sequence found in the donor can be studied.

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>Histopaque-1077&#160;</td>
			<td>Sigma-Aldrich</td>
			<td>10771</td>
			<td>solution containing polysucrose and sodium diatrizoate</td>
		</tr>
		<tr>
			<td>FACSAria II cell sorter&#160;</td>
			<td>BD Biosciences&#160;</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>96 U-bottom micro well plates&#160;</td>
			<td>Costar</td>
			<td>3799</td>
			<td></td>
		</tr>
		<tr>
			<td>Advanced Roswell Park Memorial Institute (RPMI) 1640 medium&#160;</td>
			<td>Gibco, Life Technologies</td>
			<td>12633-020</td>
			<td></td>
		</tr>
		<tr>
			<td>30% v/v EBV-containing supernatant of the B95-8 cell line&#160;&#160;</td>
			<td>ATCC</td>
			<td>CRL-1612</td>
			<td>3.4 x 108 copies/ml</td>
		</tr>
		<tr>
			<td>CpG2006&#160;</td>
			<td>Invivogen</td>
			<td>ODN 7909</td>
			<td></td>
		</tr>
		<tr>
			<td>Wi38 cells&#160;</td>
			<td>Sigma-Aldrich</td>
			<td>90020107</td>
			<td></td>
		</tr>
		<tr>
			<td>Interleukin-2</td>
			<td>Roche&#160;</td>
			<td>10799068001</td>
			<td></td>
		</tr>
		<tr>
			<td>ELISA plates</td>
			<td>Greiner Bio-One, Microlon</td>
			<td>655092</td>
			<td></td>
		</tr>
		<tr>
			<td>AffiniPure F(ab&#39;)2 Fragment Goat Anti-Human IgG, Fc&#947; Fragment Specific (unconjugated)</td>
			<td>Jackson ImmunoResearch</td>
			<td>109-006-008</td>
			<td></td>
		</tr>
		<tr>
			<td>4% non-fat dry milk (Blotting Grade Blocker)&#160;</td>
			<td>Biorad</td>
			<td>170-6404</td>
			<td></td>
		</tr>
		<tr>
			<td>Human IgG&#160;</td>
			<td>Sigma</td>
			<td>I 2511</td>
			<td>HUMAN IgG purified Immunoglobulin, 5.6 mg/ml</td>
		</tr>
		<tr>
			<td>Goat F(ab)2 antihuman IgG Fc&#947; (conjugated with peroxidase (PO))</td>
			<td>Jackson ImmunoResearch</td>
			<td>109-036-008</td>
			<td></td>
		</tr>
		<tr>
			<td>ELISA reader (Perkin Elmer 2030)&#160;</td>
			<td>Perkin Elmer&#160;</td>
			<td>2030-0050</td>
			<td></td>
		</tr>
		<tr>
			<td>Peroxidase-conjugated AffiniPure Rabbit Anti-Human IgM, Fc5&#181;&#160;</td>
			<td>Jackson ImmunoResearch</td>
			<td>309-035-095</td>
			<td></td>
		</tr>
		<tr>
			<td>SuperScript III Cells Direct cDNA Synthesis System&#160;</td>
			<td>Invitrogen&#160;</td>
			<td>18080-200</td>
			<td></td>
		</tr>
		<tr>
			<td>Applied Biosystems (ABI) GeneAm PCR System 2700</td>
			<td>Applied Biosystems</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>High Pure RNA Isolation Kit&#160;</td>
			<td>Roche</td>
			<td>11828665001</td>
			<td></td>
		</tr>
		<tr>
			<td>Reverse transcription system kit&#160;</td>
			<td>Promega</td>
			<td>A3500</td>
			<td></td>
		</tr>
		<tr>
			<td>Recombinant Taq DNA Polymerase</td>
			<td>TAKARA</td>
			<td>R001A</td>
			<td></td>
		</tr>
		<tr>
			<td>Primers (2&#956;l)</td>
			<td>Sigma</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Ultrapure Agarose&#160;</td>
			<td>Invitrogen</td>
			<td>16500-500</td>
			<td></td>
		</tr>
		<tr>
			<td>100 bp ladder</td>
			<td>Invitrogen</td>
			<td>15628-019</td>
			<td></td>
		</tr>
		<tr>
			<td>Quantity One 4.5.2 (Gel Doc 2000)</td>
			<td>Biorad</td>
			<td>170-8100</td>
			<td></td>
		</tr>
		<tr>
			<td>QIAquick PCR purification kit</td>
			<td>QIAGEN</td>
			<td>28106</td>
			<td></td>
		</tr>
		<tr>
			<td>BigDye Terminator v3.1 cycle sequencing kit&#160;</td>
			<td>Applied Biosystems</td>
			<td>4337455</td>
			<td></td>
		</tr>
		<tr>
			<td>0.1 ml reaction plate (MicroAMP Optical 96-well)</td>
			<td>Applied Biosystems</td>
			<td>4346906</td>
			<td></td>
		</tr>
		<tr>
			<td>Genetic analyser ABI300&#160;</td>
			<td>Applied Biosystems</td>
			<td>4346906</td>
			<td></td>
		</tr>
		<tr>
			<td>DH5&#945; competent cells (E. coli)</td>
			<td>Invitrogen</td>
			<td>18263-012</td>
			<td></td>
		</tr>
		<tr>
			<td>pFUSEss-CHIg-hG1 (4493 bp)</td>
			<td>Invivogen</td>
			<td>pfusess-hchg1</td>
			<td></td>
		</tr>
		<tr>
			<td>pFUSEss-CHIg-hG4 (4484 bp)&#160;</td>
			<td>Invivogen</td>
			<td>pfusess-hchg4</td>
			<td></td>
		</tr>
		<tr>
			<td>pFUSE2ss-CLIg-hk (3875 bp)</td>
			<td>Invivogen</td>
			<td>pfuse2ss-hclk</td>
			<td></td>
		</tr>
		<tr>
			<td>pFUSE2ss-CLIg-hl2 (3883 bp)&#160;</td>
			<td>Invivogen</td>
			<td>pfuse2ss-hcll2</td>
			<td></td>
		</tr>
		<tr>
			<td>SOC medium</td>
			<td>Invitrogen</td>
			<td>15544-034</td>
			<td></td>
		</tr>
		<tr>
			<td>LB-based agar medium supplemented with Zeocin (Fast-Media Zeo Agar)</td>
			<td>Invivogen</td>
			<td>fas-zn-s</td>
			<td></td>
		</tr>
		<tr>
			<td>Terrific Broth (TB)-based liquid medium supplemented with Zeocin (Fast-Media Zeo TB)</td>
			<td>Invivogen</td>
			<td>fas-zn-l</td>
			<td></td>
		</tr>
		<tr>
			<td>DNA Miniprep kit&#160;</td>
			<td>Omega Bio Technology</td>
			<td>D6942-02</td>
			<td></td>
		</tr>
		<tr>
			<td>Nanodrop (ND1000 Spectrophotometer)</td>
			<td>Nanodrop</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>LB-based agar medium supplemented with Blasticidin (Fast-Media Blast Agar)</td>
			<td>Invivogen</td>
			<td>fas-bl-s</td>
			<td></td>
		</tr>
		<tr>
			<td>Terrific Broth (TB)-based liquid medium supplemented with Blasticidin (Fast-Media Blast TB)</td>
			<td>Invivogen</td>
			<td>fas-bl-l</td>
			<td></td>
		</tr>
		<tr>
			<td>EcoRI</td>
			<td>New England Biolabs</td>
			<td>R0101S</td>
			<td>20,000 U/ml, in 10x NEBuffer EcoRI</td>
		</tr>
		<tr>
			<td>NheI</td>
			<td>New England Biolabs</td>
			<td>R0131S</td>
			<td>10,000 U/ml, in 10x NEBuffer 2.1</td>
		</tr>
		<tr>
			<td>2-Log DNA ladder</td>
			<td>New England Biolabs</td>
			<td>N3200S</td>
			<td>0.1-10.0 kb, 1,000 &#956;g/ml</td>
		</tr>
		<tr>
			<td>XmaI</td>
			<td>New England Biolabs</td>
			<td>R0180S</td>
			<td>10,000 U/ml, in 10x CutSmart Buffer&#160;</td>
		</tr>
		<tr>
			<td>BsiWI</td>
			<td>New England Biolabs</td>
			<td>R0553S</td>
			<td>10,000 U/ml, in 10x NEBuffer 3.1</td>
		</tr>
		<tr>
			<td>AvrII</td>
			<td>New England Biolabs</td>
			<td>R0174S</td>
			<td>5,000 U/ml, in 10x CutSmart Buffer&#160;</td>
		</tr>
		<tr>
			<td>FastAP Thermosensitive Alkaline Phosphatase</td>
			<td>Thermo Scientific</td>
			<td>EF0651</td>
			<td>1 U/&#181;L, in 10x FastAP Buffer</td>
		</tr>
		<tr>
			<td>DH5&#945; competent cells&#160;</td>
			<td>Invitrogen</td>
			<td>18263-012</td>
			<td></td>
		</tr>
		<tr>
			<td>PE Mouse Anti-Human IgG</td>
			<td>BD Pharmingen</td>
			<td>555787</td>
			<td></td>
		</tr>
		<tr>
			<td>anti-CD22, PerCP-Cy5.5, Clone: HIB22</td>
			<td>Fisher scientific</td>
			<td>BDB563942</td>
			<td></td>
		</tr>
		<tr>
			<td>QIAprep Spin Miniprep Kit&#160;</td>
			<td>QIAGEN</td>
			<td>27106</td>
			<td></td>
		</tr>
		<tr>
			<td>BigDye Terminator v3.1</td>
			<td>Applied Biosystems</td>
			<td>4337455</td>
			<td></td>
		</tr>
	</tbody>
</table>

generation of recombinant human igg monoclonal antibodies from immortalized sorted b cells

Finding new methods for generating human monoclonal antibodies is an active research field that is important for both basic and applied sciences, including the development of immunotherapeutics. However, the techniques to identify and produce such antibodies tend to be arduous and sometimes the heavy and light chain pair of the antibodies are dissociated. Here, we describe a relatively simple, straightforward protocol to produce human recombinant monoclonal antibodies from human peripheral blood mononuclear cells using immortalization with Epstein-Barr Virus (EBV) and Toll-like receptor 9 activation. With an adequate staining, B cells producing antibodies can be isolated for subsequent immortalization and clonal expansion. The antibody transcripts produced by the immortalized B cell clones can be amplified by PCR, sequenced as corresponding heavy and light chain pairs and cloned into immunoglobulin expression vectors. The antibodies obtained with this technique can be powerful tools to study relevant human immune responses, including autoimmunity, and create the basis for new therapeutics.

The sorting gating after staining CD22 and IgG positive cells is shown in Figure 1. In this image the area of the double positive cells &#8211; B cells producing IgG antibodies &#8211; is selected to sort all these cells in a separate tube. In the analysis, approximately 1% of the total PBMCs correspond to this double positive population. The number of sorted cells obtained will depend on the number of cells obtained in section 1.
The different outcomes after 5 weeks of EBV im...

Watch this Scientific Journal Video about Generation of Recombinant Human IgG Monoclonal Antibodies from Immortalized Sorted B Cells at JoVE.com

Generation of Recombinant Human IgG Monoclonal Antibodies from Immortalized Sorted B Cells

Synthesis of human monoclonal antibodies is the first step in studies aimed at unraveling the pathophysiological mechanisms of auto-antibody-mediated immune responses. We have developed a protocol to generate recombinant human immunoglobulin G (IgG) monoclonal antibodies from blood sorted B cells, including B-cell isolation, antibody cloning and in vitro synthesis.

Finding new methods for generating human monoclonal antibodies is an active research field that is important for both basic and applied sciences, ...

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Immunology and Infection

18.2K Views.  Maastricht University. Synthesis of human monoclonal antibodies is the first step in studies aimed at unraveling the pathophysiological mechanisms of auto-antibody-mediated immune responses. We have developed a protocol to generate recombinant human immunoglobulin G (IgG) monoclonal antibodies from blood sorted B cells, including B-cell isolation, antibody cloning and in vitro synthesis.