Ranking and Epitope Mapping of Anti-Human IL-9 Supernatants Using SPR

Bio-Rad Laboratories, Inc., a multinational manufacturer and distributor of life science research products and clinical diagnostics, today announced the availability of Bio-Rad’s technical note (bulletin 5540), which describes the screening, ranking, and epitope mapping of anti-human IL-9 supernatants.

The study described in the technical note demonstrates the rapid, precise screening, and ranking of 20 hybridoma supernatants using Bio-Rad’s SPR biosensor, the ProteOn™ XPR36 protein interaction array system. Five high-affinity antibodies are identified, and four of these were selected for further purification and epitope mapping. Two of the antibodies recognize different epitopes on the IL-9 antigen. Both epitope mapping and hybridoma ranking were accomplished efficiently using Bio-Rad’s One-shot kinetics approach and the parallel processing capability of the ProteOn XPR36 system. This work can be easily enhanced to include kinetic constant determination of hundreds of supernatants within only a few hours.

In the workflow used in this study, five supernatants were screened at a time against five antigen concentrations, and one channel was reserved for referencing. Using this configuration, both the anti-mouse IgG and antibody-containing supernatants were injected into the same set of channels (ligand channels), followed by IL-9 injection into the orthogonal analyte channels. Bio-rad’s One-shot kinetics approach can be expanded to include all six available analyte channels and interspot referencing to conduct supernatant screening, yielding equally reliable results with greater throughput. This is accomplished by using the ligand channel for immobilization of anti-mouse IgG, the analyte channel for capture of the supernatant clones, and the ligand channels for IL-9 flow.

Availability
Bio-Rad’s technical note (bulletin 5540) is available either from a local Bio-Rad sales office or can be downloaded via the article webpage.