Poster #RP226
Epitope mapping of monospecific antibodies using cell display
Johan Rockberg*, John Löfblom*, Mathias Uhlén*
*Royal Institute of Technology, Stockholm, Sweden
One delimiting factor in proteomic research is lack of specific ligands enabling in depth characterisation of proteins. The Swedish Human Proteome Resource (http://www.hpr.se) addresses this problem in an attempt to generate affinity purified monospecific antibodies (msAb) towards each individual human protein. These antibodies are further used for tissue localisation studies using Tissue Microarray of normal and cancer tissue samples (http://www.proteinatlas.org).
Here we describe a novel high through put method for mapping of antibody epitopes. The technique involves fragmentation of the antigen DNA and subsequent cloning into a gram-positive expression vector yielding library. The library is transformed into the gram positive strain Staphylococcus aureus for presentation of the epitope on the cell surface. Cells presenting epitopes recognised by the monospecific antibodies are sorted out using flowcytometry (FACS) in a 96 well format and sequenced using pyrosequencing. Data is processed using Bioperl and BLAST to map the epitope back to the antigen sequence. Our current results will be presented.