Name: Antibody Profiling by Luciferase Immunoprecipitation Systems (LIPS) (Video) | JoVE Journal
Uploaded: 2009-10-07T17:25:00.000+00:00
Duration: 12 min 19 s
Description: Learn Luciferase Immunoprecipitation Systems (LIPS) for antibody profiling using COS-1 cells and crude extracts. This method enables efficient quantification of antibody titers for disease diagnosis and research.

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This research was supported by the Intramural Research Program of the NIDCR.

1. Schematic Overview:
This video demonstrates the steps involved in performing the LIPS assay. Antigens are expressed in Cos1 cells as recombinant Renilla luciferase (Ruc)-antigen fusions, and crude extracts are obtained and used without purification. The LIPS assay is initiated by incubating crude Ruc-antigen extracts with patient sera in microtiter wells. The antibody-antigen mixture is then transferred to a 96-well filter plate containing protein A/G beads to capture IgG molecules. After washing the filter plate containing the protein A/G beads, antibody bound Ruc-antigen is measured by the addition of coelenterazine substrate and light units are measured with a luminometer.
PART 1: Transfection of Plasmids for production of Renilla-Antigen Fusion Proteins
Set-up: Cos1 cells are cultured in DMEM-10% FCS using standard tissue culture protocols. Plasmids for Renilla luciferase fusions have been described previously1. DNA for these plasmids is prepared using a Midiprep kit from Qiagen. The yield should be approximately 1 -3 mg. Measure the DNA concentration and store as a 1000 &mu;g/ml stock solution at -20&deg;C.
Procedure:
<ol>
<li>One day before transfection, split Cos-1 cells into new 100 x 20 mm dishes at approximately 2 X 106 per plate and incubate at 37 &deg;C.
</li>
<li>On the following day, the Cos-1 cells should be 80-95% confluent. Label 1.5 ml polypropylene microfuge tubes for each plasmid DNA to be transfected. Allow the FuGENE-6 transfection reagent, which is stored at 4&deg; C, to warm up to room temp.</li>
<li>Add 94 &mu;l of Opti-MEM media to each microfuge tube. Next add 6 &mu;l of FuGENE 6 to the Opti-MEM media without touching the side wall. </li>
<li>Incubate the mixture for 5 minutes at room temperature.</li>
<li>Add 1-2 &mu;g (from 1mg/ml DNA stock) of plasmid for Renilla luciferase antigen fusion construct. Mix and then incubate the mixture for 15 minutes at room temperature.</li>
<li>Transfer the DNA-FuGENE 6-Opti-MEM solution to the cells by dripping it evenly into the media of the Cos1 cells.</li>
</ol>
PART 2: Harvesting Renilla-antigen Fusions
<ol>
<li>Two days after transfection, the Cos-1 cells are harvested. This is initiated by removing the media and then rinsing the cells with 6 ml of PBS. After decanting the PBS, pipette away any residual PBS from the tissue culture dish.</li>
<li>Add 1.4 ml of cold lysis buffer composed of 50 mM Tris, pH 7.5, 100 mM NaCl, 5 mM MgCl2, 1% Triton X-100, 50% glycerol and protease inhibitors (2 tablets of complete miniprotease inhibitor cocktail per 50 ml of lysis buffer). Harvest cells with a cell scrapper and quickly transfer half of the lysate to each of two 1.5 ml microfuge tubes on ice.</li>
<li>A Branson Sonifier 150 is used to break the cells open. Place the microcentrifuge tube containing the cell lysate on ice and pulse for 5 sec, 5 sec and 5 sec with sonication settings of 2, 2 and 4, respectively.</li>
<li>Centrifuge the cell lysate at 12,500 RPM for two 4 minute spins at 4 &deg; C. After the first spin, gently invert the tubes to remove the loosely attached debris from the sidewall of the tube. After the second spin, carefully transfer the supernatant, without disrupting the pellet, from the two tubes to a new microfuge tube on ice. </li>
<li>Calculate the light units (LU) per &mu;l of lysate. To measure the LU, dilute 1 &mu;l of lysate with 8 &mu;l of PBS in a new microfuge tube. Directly add 100 &mu;l of 1X coelenterazine substrate to the diluted mixture and immediately measure luminescence in the tube using a tube luminometer (20/20n Turner Scientific) with a 5 second read.</li>
<li>Store the Ruc-antigen lysate at -20&deg; C for 1-2 days or store for longer period of times in aliquots at -80&deg; C.</li>
</ol>
PART 3: Preparing a Sera Master Plate
<ol>
<li>Make a sera master plate by first adding 450 &mu;l of buffer A (50 mM Tris, pH 7.5, 100 mM NaCl, 5 mM MgCl2, 1% Triton X-100) to each well of a 96-deep-well polypropylene microtiter plate. At this step, a dye, Phenol Red, can also be included in buffer A (final concentration is 0.2 &mu;g/ml in Buffer A) to act as a tracer for monitoring future sera sample addition and other steps of the LIPS assay.</li>
<li>Next add 50 &mu;l of sera from each sample to the different wells containing 450 &mu;l of buffer A. Note this is a 1:10 dilution of the sera in buffer A. Typically sera is not added to the last two wells of the master plate because this is reserved for the buffer blanks.</li>
<li>Before using the master plate, it is extensively shaken (1-2 hours) on a rotator platform. The serum in the master plate is stable for at least 1 month (or longer) at 4&deg; C, if stored correctly to prevent evaporation.</li>
<li>As described below, this master plate provides 10 &mu;l of diluted sera to be repeatedly removed for profiling of the sera against multiple antigens. Larger and smaller master plates can also be employed. Seal the plate well with Parafilm when it is not being used.</li>
</ol>
PART 4: LIPS assay
<ol>
<li>Polypropylene 96-shallow well microtiter plates are used to test sera. In the first step, add 40 &mu;l of buffer A to each well of the 96-well plate using an 8 channel micropipette.</li>
<li> Next take 10 &mu;l of diluted sera (1 &mu;l sera equivalent) from the master plate and add it directly to each well of the working plate using an 8 channel micropipette.</li>
<li> A master mix containing the Ruc-antigen extract is next formulated such that 1 X 107 light units (LU) is added in 50 &mu;l of buffer A to each well. Lower inputs (as little as 1 X 106) can also be used, but result in a lower dynamic range. Make this master mixture and pipette 50 &mu;l of Ruc-antigen mixture to each well.</li>
<li>Incubate the plate on a rotary shaker for 1 hour at room temperature. </li>
<li>During the incubation, add 5 &mu;l of a 30% suspension of Ultralink protein A/G beads (Pierce Biotechnology, Rockford, IL) in PBS to the bottom of each well of a new 96 well filter HTS plate (Millipore, Bedford, MA).</li>
<li>After the 1 hour incubation, transfer the 100 &mu;l Ruc-antigen antibody reaction mixture to 96 well filter HTS plates containing the protein A/G beads using an 8 channel micropipette.</li>
<li>Incubate the 96-well filter plate on a rotary shaker for 1 additional hour at room temperature. </li>
<li>Next wash the filter plate on a vacuum manifold. Each well is washed 8 times with 100 &mu;l of Buffer A, followed by two times with 100 &mu;l of PBS. This can be performed manually or with a robotic pipetting workstation. </li>
<li>Following the last wash, the vacuum is turned off. Remove the filter plate and blot it dry using a stack of paper towels or filter paper making sure to remove moisture on the top and bottom of the plate.</li>
</ol>
PART 5: Measuring Luminescence and data analysis
Set-up:
A Berthold LB 960 Centro microplate luminometer is used for determining luminescence in each well using a single injector. Once the machine is on, rinse the injector with distilled H2O using the injector wash cycle. Coelenterazine substrate is prepared using the Promega Renilla substrate kit as described by the manufacturer. Typically 6 ml of 1X coelenterazine substrate mix (i.e. 60 &mu;l coelenterazine stock plus 6 ml of 1X buffer) is prepared for priming the machine and running one full 96-well plate. Before analyzing the plate, the Berthold LB 960 Centro microplate luminometer is primed with 1X coelenterazine substrate. Open a program file containing the setting for injecting the substrate and reading the plate. For these measurements, 50 &mu;l of coelenterazine substrate is injected, the plate is shaken for 2 sec, followed by a 5 sec read of luminescence.
<ol>
<li>Although the plate luminometer has the capacity to read the entire plate, a partial read of the plate can also be selected (under the read menu). Start the program, which initiates reading of the plate.</li>
<li>After the run, remove the microtiter filter plate promptly to prevent spillage in the luminometer. Export the data generated with the MikroWin program into an Excel format for analysis.</li>
<li>We recommend evaluating the sera from two independent runs. Data is then averaged to generate the LU titer values for each sample. These values can further be adjusted to subtract the buffer blanks.</li>
<li>Additional data analysis such as determining the cutoff can be calculated by taking the mean plus 3 or 5 standard deviations of the control values.</li>
</ol>

<ol><li>Burbelo, P. D., Goldman, R., Mattson, T. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((A+simplified+immunoprecipitation+method+for+quantitatively+measuring+antibody+responses+in+clinical+sera+samples+by+using+mammalian-produced+Renilla+luciferase-antigen+fusion+proteins%5BTitle%5D)+AND+%22BMC+Biotechnol%22%5BJournal%5D)">A simplified immunoprecipitation method for quantitatively measuring antibody responses in clinical sera samples by using mammalian-produced Renilla luciferase-antigen fusion proteins.</a> BMC Biotechnol. 5, 22-22 (2005).</li>
<li>Burbelo, P. D., Leahy, H. P., Iadarola, M. J., Nutman, T. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((A+Four-Antigen+Mixture+for+Rapid+Assessment+of+Onchocerca+volvulus+Infection%5BTitle%5D)+AND+%22PLoS+Negl+Trop+Dis%22%5BJournal%5D)">A Four-Antigen Mixture for Rapid Assessment of Onchocerca volvulus Infection.</a> PLoS Negl Trop Dis. 3, e438-e438 (2009).</li>
<li>Burbelo, P. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Sensitive+and+robust+luminescent+profiling+of+anti-La+and+other+autoantibodies+in+Sj+gren%E2%80%99s+syndrome%5BTitle%5D)+AND+%22Autoimmunity%22%5BJournal%5D)">Sensitive and robust luminescent profiling of anti-La and other autoantibodies in Sj gren’s syndrome.</a> Autoimmunity. 139, 241-245 (2009).</li>
<li>Burbelo, P. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Rapid+antibody+quantification+and+generation+of+whole+proteome+antibody+response+profiles+using+LIPS+%28luciferase+immunoprecipitation+systems%29%5BTitle%5D)+AND+%22Biochem+Biophys+Res+Commun%22%5BJournal%5D)">Rapid antibody quantification and generation of whole proteome antibody response profiles using LIPS (luciferase immunoprecipitation systems).</a> Biochem Biophys Res Commun. 352, 889-895 (2007).</li>
<li>Burbelo, P. D., Groot, S., Dalakas, M. C., Iadarola, M. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((High+definition+profiling+of+autoantibodies+to+glutamic+acid+decarboxylases+GAD65%2FGAD67+in+stiff-person+syndrome%5BTitle%5D)+AND+%22Biochem+Biophys+Res+Commun%22%5BJournal%5D)">High definition profiling of autoantibodies to glutamic acid decarboxylases GAD65/GAD67 in stiff-person syndrome.</a> Biochem Biophys Res Commun. 366, 1-7 (2008).</li>
<li>Burbelo, P. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((A+new+luminescence+assay+for+autoantibodies+to+mammalian+cell-prepared+insulinoma-associated+protein+2%5BTitle%5D)+AND+%22Diabetes+Care%22%5BJournal%5D)">A new luminescence assay for autoantibodies to mammalian cell-prepared insulinoma-associated protein 2.</a> Diabetes Care. 31, 1824-1826 (2008).</li>
<li>Burbelo, P. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Serological+diagnosis+of+human+herpes+simplex+virus+type+1+and+2+infections+by+luciferase+immunoprecipitation+system+assay%5BTitle%5D)+AND+%22Clin+Vaccine+Immunol%22%5BJournal%5D)">Serological diagnosis of human herpes simplex virus type 1 and 2 infections by luciferase immunoprecipitation system assay.</a> Clin Vaccine Immunol. 16, 366-371 (2009).</li>
<li>Burbelo, P. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Highly+quantitative+serological+detection+of+anti-cytomegalovirus+%28CMV%29+antibodies%5BTitle%5D)+AND+%22Virol+J%22%5BJournal%5D)">Highly quantitative serological detection of anti-cytomegalovirus (CMV) antibodies.</a> Virol J. 6, 45-45 (2009).</li>
<li>Burbelo, P. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Four-antigen+mixture+containing+v-cyclin+for+serological+screening+of+human+herpesvirus+8+infection%5BTitle%5D)+AND+%22Clin+Vaccine+Immunol%22%5BJournal%5D)">Four-antigen mixture containing v-cyclin for serological screening of human herpesvirus 8 infection.</a> Clin Vaccine Immunol. 16, 621-627 (2009).</li>
<li>Ramanathan, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((A+luciferase+immunoprecipitation+systems+assay+enhances+the+sensitivity+and+specificity+of+diagnosis+of+Strongyloides+stercoralis+infection%5BTitle%5D)+AND+%22J+Infect+Dis%22%5BJournal%5D)">A luciferase immunoprecipitation systems assay enhances the sensitivity and specificity of diagnosis of Strongyloides stercoralis infection.</a> J Infect Dis. 198, 444-451 (2008).</li>
</ol>

LIPS requires minimal assay optimization and, due to its simplicity, high quality data can typically be generated using LIPS in under two weeks for any given antigen. The most time consuming steps are cloning and generating the appropriate plasmid expression vector containing the Ruc-antigen fusion. Once these plasmids are generated, single or multiple antigens can be rapidly tested with LIPS as described above. It should be noted that LIPS is quite versatile such that sera can also be tested in a tube format or alternatively on a microtiter filter plate with the aid of a BIOMEK robotic workstation2 or a plate washer with vacuum filtration. This highly scalable system allows for the parallel LIPS profiling of a panel of human autoantigens3 or the whole proteome of a virus4. It is likely that many different antibody profiles generated by LIPS will be useful for diagnostics3-9, antigen discovery9, following the course of a treatment10, vaccine monitoring and has broad implications for specific disease states and for public health in general.

<table><tbody><tr><td>HiSpeed Plasmid Midi KIt</td><td>Qiagen</td><td>12643</td><td></td></tr><tr><td>100 x 20 mm tissue culture dishes</td><td>Fisher Scientific</td><td>353003</td><td></td></tr><tr><td>Opti-MEM</td><td>Invitrogen</td><td>31985</td><td></td></tr><tr><td>FuGENE 6</td><td>Roche Group</td><td>1814443</td><td></td></tr><tr><td>Complete, Mini protease inhibitor cocktail</td><td>Roche Group</td><td>11836153001</td><td></td></tr><tr><td>Polypropylene 96 DeepWell 1 ml plate</td><td>Fisher Scientific</td><td>12-566-120</td><td>Deep well plate with lid and seal with Parafilm</td></tr><tr><td>Polypropylene microtiter plate</td><td>Fisher Scientific</td><td>12-566-120</td><td></td></tr><tr><td>HTS Filter plate</td><td>EMD Millipore</td><td>MSBVN1B50</td><td></td></tr><tr><td>Ultralink Immobilized Protein A/G</td><td>Pierce, Thermo Scientific</td><td>53133 (10ml)</td><td></td></tr><tr><td>Renilla Luciferase Assay System</td><td>Promega Corp.</td><td>E2820</td><td>For 2000 assays</td></tr><tr><td>Centro microplate luminometer</td><td>Berthold Technologies</td><td>LB 960</td><td></td></tr></tbody></table>

antibody profiling by luciferase immunoprecipitation systems (lips)

Antibody Profiling by Luciferase Immunoprecipitation Systems (LIPS)

Technologies for comprehensively understanding and quantifying antibody profiles to autoantigens and infectious agents may yield new insights into disease mechanisms and may elucidate new markers to substratify disease with different clinical features and better understand pathogenesis. We have developed a highly quantitative method called Luciferase Immunoprecipitation Systems (LIPS) for profiling patient sera antibody responses to autoantigens and pathogen antigens associated with infection. Unlike ELISAs, the highly sensitive LIPS is easily implemented to survey humoral serological response profiles to different antigens in a universal format and produces dynamic antibody titer ranges up to 6 log10 for some antigens. In these studies, quantitative profiling by LIPS of patient humoral responses against panels of antigens or even the entire proteome of some pathogens (i.e. HIV), is typically more informative than testing a single antigen by ELISA. In addition, LIPS also eliminates time and effort needed to produce highly purified antigens as well as the labor-intensive assay optimization steps needed for standard ELISAs. Here we provide a detailed protocol describing the technical aspects of performing LIPS assays for readily profiling antibody responses to single or multiple antigens.

The technical aspects of performing LIPS (Luciferase Immunoprecipitation Systems) are described. The overall approach involves expressing chimeric genes encoding antigens fused to Renilla luciferase (Ruc) in mammalian cells. Crude Ruc-antigen extracts are then prepared and, without purification, employed in immunoprecipitation assays to quantify antibodies.

Technologies for comprehensively understanding and quantifying antibody profiles to autoantigens and infectious agents may yield new insights into disease ...

This video demonstrates the steps involved in performing the lips. Assay antigens are expressed in CO one cells as recombinant ran vanilla luciferase or rook antigen fusions. Crude extracts are obtained and used without purification.The lips assay is initiated by incubating crude rook antigen extracts with patient SRA. In Microtiter wells the antibody antigen mixture is then transferred to a 96 Well filter plate containing protein A G beads to capture IgG molecules after washing the filter plate containing the protein AG beads. Antibody bound rook antigen is measured by the addition of linine substrate and light units are measured with a luminometer.Hi, I'm Dr.Catherine Chang from the Laboratory of Sensory Biology at the National Institute of Dental and C Craniofacial Research. Today we'll show you the procedure for lips luciferase immunoprecipitation systems. We use lips in our laboratory to measure antibody titers in order to diagnose disease and or infection.Subst stratify disease states monitor vaccination and other applications involved in generating antibody profiles. So let's get started. Prior to beginning transfection plasmids for vanilla luciferase fusions are prepared in advance as described in the BMC biotechnology paper.BYO etal 2005 plasma DNA is prepared using a MIDI prep kit with a yield of one to three milligrams and stored as a one milligram per milliliter stock solution at minus 20 degrees Celsius. Cost one cells used in transfection are cultured in DMEM 10%FCS using standard tissue culture protocols. One day before transfection split costs one cells into new 100 by 20 millimeter dishes to approximately two times 10 of the six cells per plate and incubate at 37 degrees Celsius on the following day.The cost one cells should be 80 to 95%Confluent allow the FU gene six transfection reagent which is stored at four degrees Celsius to warm up to room temperature while waiting for the FU gene to warm label 1.5 milliliter polypropylene micro fuge tubes for each plasma DNA to be transfected being careful not to touch the sidewall of the tubes. Add six microliters of fusion gene six to the tubes, which should already contain 94 microliters of optimum media incubate for five minutes. At room temperature, add one to two micrograms of plasmid for ran Lucifer antigen fusion construct mixed by inverting the tube several times, centrifuge briefly and incubate at room temperature for 15 minutes.Transfer the entire DNA fusion six optimum solution to the cells by dripping it evenly into the media of the cos. One cells incubate transfected cos one cells for two days then harvest. To begin harvesting fusion protein, remove media and wash the cells with six milliliters of PBS.Pipe it away any residual PBS from the tissue culture dish add 1.4 milliliters of cold lysis, buffer and harvest cells with a cell scraper and quickly transfer half of the lysate to each of two 1.5 milliliter micro fuge tubes on ice. A Branson SOLIDIFIER one 50 is used to break the cells open. Place the micro centrifuge tube containing the cell lysate on ice and pulse for five seconds.Five seconds and five seconds. With sonication settings of two, two and four respectively. Centrifuge the cell lysate at 12, 500 RPM for two four minutes.Spins at four degrees Celsius. Gently inverting the tubes between spins to remove the loosely attached debris from the sidewall of the tube. Then carefully transfer the supernatant without disrupting the pellet from the two tubes to a new micro fuge tube on ice.To measure the light units or lu of the lysate dilute one microliter of lysate with eight microliters of PBS in a new micro fuge tube directly add 100 microliters of one celent ine substrate to the diluted mixture and immediately measure luminescence in the tube using a tube luminometer with a five second read from this step forward. Remember to use safety precautions when working with human and animal S samples to make a serum master plate the source of patient antibodies for antigen profiling. First add 450 microliters of buffer A to each well of a 96 deep well polypropylene microtiter plate.At this step, a dye phenol red can also be included in buffer A to act as a tracer from monitoring future SRA sample edition and other steps of the lips assay. Next, add 50 microliters of serum from each sample to each well containing 450 microliters of buffer. A note, this is a one to 10 dilution of the SRA in buffer.A typically SRA is not added to the last two wells of the master plate because this is reserved for the buffer blanks before storing the master plate for future use. It is extensively shaken for one to two hours on a rotator platform. At 650 RPM, the serum is stable for at least one month or longer at four degrees Celsius and the plate can be sealed with parfum to prevent evaporation if it will be stored prior to running the lips assay, organize a spreadsheet containing the sample identification numbers and their associated wells on the master plate polypropylene 96 shallow well microtiter plates are used as working plates to test sera.In the first step, add 40 microliters of buffer A to each well of the 96 well plate using an eight channel micro pipette. Next, take 10 microliters of diluted serum from the master plate and add it directly to each well of the working plate using an eight channel micro pipette. After use seal the master plate with paraform, replace the lid on the master plate, then cover with Saran wrap and store at four degrees Celsius.A master mix containing the rook antigen extract is next Formulated such that one times 10 to the seventh lu is added in 50 microliters of buffer A to each. Well make this master mix mixture and pipette 50 microliters of rook antigen mixture to each. Well cover the plate with a polystyrene plate cover and incubate on a rotary shaker at 100 RPM for one hour.At room temperature during the incubation retrieve a 1.5 milliliter aliquot of a 30%ultra link protein ag bead suspension in PBS from the fridge. Add five microliters to the bottom of each well of a new 96 well filter HTS plate After the one hour plate incubation transfer the 100 microliters of rook antigen antibody reaction mixture to 96. Well filter HTS plates containing the protein ag beads using an A channel micro pipette incubate the 96 well filter plate on a rotary shaker for one additional hour at 100 RPM at room temperature.Next, wash the filter plate using a Biome FX automation workstation With a vacuum manifold, each well is washed eight times with 100 microliters of buffer A followed by two times with 100 microliters of PBS following the last wash, the vacuum is turned off. Remove the filter plate and blotted dry using a stack of paper towels or filter paper, making sure to remove moisture on the top and bottom of the plate. A Burt hold LB nine 60 Centro Microplate luminometer is used for determining luminescence in each well of the plate.Turn the machine on and rinse the injector with distilled water. Using the injector wash cycle INE substrate is used for priming and running the machine and is prepared using the Promega ranil substrate kit following manufacturer's instructions, typically six milliliters of one excellent tine substrate mix is needed for one plate. Load the substrate mixture into the luminometer open a program file containing the setting for injecting the substrate and reading the plate.For these measurements. 50 microliters of soine substrate is injected. The plate is shaken for two seconds, followed by a five second read of luminescence.Start the program which initiates reading of the plate after the run, remove the microtiter filter plate promptly to prevent spillage in the luminometer. The data is automatically exported from the microwind program into an Excel format for further analysis. Averaging results for two different runs with the same sera.In order to generate lu titer values for each sample is recommended. The duplicate samples should show high concordance in titer values between the two runs. For data plotting, the lu titer values can further be adjusted to subtract the buffer blanks as shown here.The sensitivity and specificity of the assay can also be calculated by utilizing cutoffs derived from the mean plus three or five standard deviations of the control samples. We've just shown you how to measure antibody titers Using lips, LIPS requires minimal assay optimization and because of its simplicity can be used to generate high quality data in under two weeks for any given antigen. When working with human Sarah, it is important to remember to take appropriate safety precautions.And keep in mind, lifts is highly scalable and because of this can be used to measure a small number of samples using manual washing or a full plate using a robotic working station with such versatility, we think lips will be highly useful in sero antigenic analysis and have broad implications in disease analysis and the public health in general. Well, that's it. Thanks for watching and good luck with your antibody profiling experiments.

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Biology

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Antibody Profiling by Luciferase Immunoprecipitation Systems (LIPS)

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