Given the variety of techniques for making antibodies—both monoclonal and polyclonal ones—companies must ensure that scientists receive molecules that function as advertised. The steps required to produce an effective antibody vary as widely as the antibodies themselves.
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Scientists at New England Peptide (Gardner, Mass.) start making their polyclonal antibodies by injecting the target protein into rabbits, although they can use other species. After that, says Scott Lewis, director of the company’s antibody division, “We have set protocols that we follow.” He adds, “That’s important to have a good base for what you’re doing.”
He also notes that a company must pay careful attention to what the customer wants and how it will be used. “The design process is very important, because you need to vet all of the activity requirements, such as concerns about cross-reactivity,” says Lewis. “Usually, you’re just looking at one protein in a family, so you need to be sure that the antibody only detects that protein and not others.”
As Lewis points out, “A customer looks for a custom antibody when nothing is available in a catalog to meet their needs.” And that happens often even with today’s bulging catalogs of antibodies.
At Novus Biologicals (Littleton, Colo.), for example, customers can order a range of primary antibodies made in-house or manufactured by other vendors. For primary antibodies made in-house, Novus offers about 55,000. It also carries more than 130,000 primary antibodies and related products made by other companies. “If a customer needs a large quantity of a very specific antibody, we will also make that for them,” says Stephanie Peacock, director of marketing.
For in-house primary antibodies, the quality control includes a Western blot to verify the size of the antibody and immunocytochemistry and immunohistochemistry to verify the correct subcellular localization.
If a customer experiences any difficulty using a primary antibody purchased from Novus Biologicals, the company stands behind the product. The company policy states: “If you cannot get a product to work in an application or species stated on our datasheet, our technical service team will troubleshoot with you to get it to work.” If that doesn’t solve the problem, says Peacock, “We offer a 100% guarantee. So the primary antibody can be replaced free of charge or we provide a full refund.” This applies to both antibodies made in-house and by other vendors.
Focusing on FlowAt BD Biosciences (San Jose, Calif.), scientists develop monoclonal antibodies designed for use in flow-cytometry applications. “The majority of our antibodies target proteins important in the field of immunology,” says Bob Balderas, vice president – biological sciences, BD Biosciences. “Within that, we provide antibodies that see receptors on the surface, proteins inside the cells, or proteins secreted by cells.”
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To get the best antibodies, the BD Biosciences team turns to experts in academic labs or at biotech or pharma. “These are the experts on the receptors,” says Balderas. “They build the model system to test these antibodies.” Then, the BD Biosciences team follows what Balderas calls a “very regimented process.” He adds, “All of the BD antibodies undergo a rigorous development and QC process, which includes both analytical and functional readouts.”
It takes such collections of control to make sure that the resulting antibodies perform as promised. Likewise, designing an antibody for a particular target to be studied with a specific platform also enhances the performance of a product.
About the author
Mike May is a publishing consultant for science and technology based in Austin, Texas.