Epitope Fingerprinting with polyclonal Antibodies
A few hundred antibody molecules are sufficient for epitope mapping. A single selection experiment with 20-100 µl serum yields enough data to cover several hundred epitopes! This application has been successfully tested in several applications for epitope fingerprinting in research projects. Since the sensitivity of the approach is high and the number of antibody molecules required for a successful epitope fingerprinting is low, even very diluted polyclonal antibody solutions can be mapped. Once peptide data sets are generated, they can be searched repeatedly for antibody epitopes in any suspected antigen. This is the perfect way to save time and money.
It is important to remember that we use a completely naïve approach instead of using dedicated libraries. The epitope identification is solely based on the statistical analysis of NGS data comprising several hundred thousand of peptide sequences. This allows finding binding peptide motifs to hundreds of antibodies, including most allowed variations of the peptides and structures potentially binding the antibody, and to predict species and cross reactivity for individual antibodies. This has been recently published for food allergies.
Mapping of vaccine and infectious agent epitopes in vaccinated rabbit’s, infected patient’s and infected/vaccinated mini-pig sera. Sites for epitopes from selections on these sera are visible as enrichment of 4-mers comprising the antigen’s protein. Identified peptide epitopes have been validated in peptide arrays and the immune response of the different species is surprisingly similar.