Antibody and T cell-epitope mapping

Overview

Epitope mapping is the process of identifying the specific peptide sequences on an antigen that elicit an immune response - either by binding to antibodies or MHC molecules. Epitope identification requires a systematic screening of the antigen, which can be difficult when the antigen has multiple conformations or binding domains. Since the development of therapeutics is dependent on having a detailed knowledge of these domains, peptide libraries are used to display multiple short, linear peptide fragments in parallel to deduce specific epitopes. The most common applications for epitope mapping are for T cells and antibodies.

T cell epitope mapping

T cell epitopes are components of proteins on antigen-presenting cells that elicit an immune response following T cell recognition and binding. Identification of these epitopes is critical for developing effective immune disease therapeutics. The peptide library is designed such that overlapping segments of the entire antigen are added to each well of a 96-well plate. T cell cultures or purified receptors are then added to the library and binding can be assessed by flow cytometry and other cellular assays. Epitope discovery by this method has been especially useful for developing vaccines for viral diseases and cancer.