ProSci, Inc. produces custom polyclonal and monoclonal antibodies at prices similar to other companies. What sets their services apart is the responsive customer service, easy ordering process, customized antibody packages, immune response guarantee, and accelerated protocols for polyclonal antibody production. They also provide 200ml of serum, which is twice what other companies provide for the same price. The prices for add-on services are listed right on the order form and are also more reasonable than other companies. Add-on services include shipping, peptide phosphorylation, project extension, exsanguination and Western blot services. The exception is affinity purification of the sera which is expensive considering the ease of this process. I recommend performing this in your own lab for less than half the price.
ProSci offers four different polyclonal packages depending on the services needed. The most popular service (protocol II) includes peptide synthesis/conjugation, an immunization protocol for two animals, and an ELISA report on the first bleed. This service is priced slightly below comparable services from other companies, but includes extras like design of the peptide and 10mg of peptide shipped with the first bleed. The immune response guarantee means that if you choose the peptide they recommend after consultation, they will redo the project (including synthesis of a new peptide if necessary) until they produce antisera that gives an immune response by ELISA. Note that this does not guarantee your antibody will work for applications like Western blotting, immunoprecipitation or immunofluorescence.
Our lab has contracted with ProSci for three polyclonal antisera over 1.5 years. During that time they have remained the most cost effective service we have found for quality antibody production. I have personally worked with the same Customer Service Manager for all three contracts and she always gets back to us promptly and courteously with a peptide analysis and a recommended sequence. For the first project, I independently performed an analysis of peptide antigenicity and hydrophilicity for comparison with ProSci’s analysis and it matched up perfectly. We independently chose the same peptide for the project and it produced a robust immune response in both animals.
Upon selection of a peptide, I faxed in the downloadable order form and quickly received a schedule of the protocol. All three projects were on schedule and we received periodic updates when each bleed was ready to ship. ProSci shipped the synthesized peptide and pre-immune sera with the first bleed. This allowed us to make a peptide affinity column, purify the 1st bleed and test the product before the second bleed arrived 2 weeks later. ProSci was also careful to check with us as the end of the protocol approached so that we could make a decision about termination or continuation of the project.
For all three projects the antibodies were made against peptides and then used for immunofluorescence and Western blotting. Without purification, the antibodies worked very well for both applications on over-expressed proteins. However, our endogenous protein was expressed at very low levels and not detectable with unpurified sera. This is not uncommon with peptide targeted serum. In order to detect the endogenous protein we had to purify the sera over affinity columns of recombinant full length protein. By purifying over the protein column, we were able to easily detect endogenous protein by Western blot. We are currently collaborating with ProSci to make a monoclonal antibody against native full length recombinant protein which is expected to work for immunofluorescence applications.
Our experiences with ProSci have been exceptional. As previously mentioned, we are currently planning a fourth project with them to make a custom monoclonal antibody and plan to work with them in the future for our custom antibody needs.
Rebecca A. MacCorkle, Ph.D.
Baylor College of Medicine
Department of Molecular & Cellular Biology