A common reagent used by HuBMAP Consortium members to label proteins and other biomolecules is the monocolonal antibody that recognizes a biomolecule of interest. Being biological products, such antibodies need to be validated for their ability to bind the target molecule with sufficient strength and specificity of signal—particularly if they are acquired from a commercial source. As part of the new HuBMAP Antibody Working Group, the Northwestern Rapid Technology Implementation (RTI) project will establish appropriate validation steps for all commercial antibodies and provide their expertise in immunoprecipitation with mass spectrometry (IP-MS), a method that combines precipitation of the antibody-target complex from solution with MS analysis. The latter demonstrates that the antibody has bound the target with sufficient specificity by fragmenting the bound biomolecules and analyzing their components as they emerge from an MS separation column.

While multiple HuBMAP members have an interest in antibody validation by IP-MS, groups’ technical expertise with the method varies. To serve the needs of the consortium balanced against the capacity of the Northwestern RTI, the group will pursue two avenues for validating antibodies. The first, offered to groups with IP-MS expertise, will be a “Best Practices for IP-MS” protocol available on HuBMAP’s protocols.io site so that these groups can perform the method in-house. For groups less familiar with IP techniques or projects of high priority to the larger HuBMAP Consortium, the Northwestern RTI will perform the validation using antibody information and target tissue specimens supplied by other HuBMAP groups.