Characterization of Circulating Antibodies Using Next Generation Sequencing and Mass Spectrometry
Deep sequencing of peripheral blood mononuclear cells (PBMCs) has recently provided the ability to characterize a snapshot 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. We employ 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. Furthermore, our proteogenomic platform enables us to perform antibody discovery and identify candidates directly from serum.