Recent developments in deep sequencing of peripheral blood mononuclear cells now provides a molecular-level view of the complex immunoglobulin repertoire. This sequenced antibody repertoire provides a wealth of information, but is a poor proxy for circulating antibodies. Direct interrogation of serum antibodies using mass spectrometry provides a complementary view of the immune response.
Here, Dr. Castellana shares how she and her team employed a proteogenomic approach integrating sequenced antibody transcripts from multiple tissue types with purified serum antibodies from a rabbit immunization experiment. "We compare repertoires across time points and tissue origins... our proteogenomic platform enables us to perform antibody discovery and identify candidates directly from serum."