November 6, Thu 2014
4:00 pm, MRB 200
Dr. Brandon DeKosky
Dept. of Chemical Engineering, University of Texas at Austin
Decoding Antibody Repertoires: Next-Generation Analyses of Vaccination and Disease
Antibodies constitute the fastest-growing class of biotherapeutics and are invaluable as diagnostic agents. More importantly, antibodies comprise the effector arm of humoral immunity in humans and animals and play a central role in protection against disease. Recent advances in high-throughput (NextGen) DNA sequencing permit analysis of millions of B cells from a single individual but are hampered by two major limitations: i) antibodies consist of two different polypeptide chains and conventional NextGen sequencing fails to identify their native pairing, and ii) while it is straightforward to determine an aggregate (polyclonal) serum antibody response, available techniques provide no information on the number, relative concentrations, nor functional characteristics of individual antibodies that comprise adaptive immune responses.
To address these issues we developed two complementary technologies: i) a single-cell sequencing platform for determination of native antibody heavy and light chain pairs from millions of B cells in a one-day experiment, and ii) the use of proteomic mass spectrometry to determine the concentration of individual serum antibodies. We are applying these technologies for detailed molecular analysis of the human immune response to several vaccines and for discovering new broadly neutralizing antibody pathways against HIV-1 and influenza. We are also analyzing developmental B-cell subsets via sequencing and in silico structural modeling to measure the global repertoire changes (in terms of gene usage, charge, hydrophobicity, etc.) that result from B-cell activation and positive selection during immune responses.