MIP-BINDERS FOR SEQUENCE SPECIFIC PHOSPHOPEPTIDE CAPTURE AND MULTIPLEX STUDIES OF PHOSPHOSIGNALING

Immunoaffinity enrichment based on antipeptide antibodies coupled to mass spectrometry based identification and quantification is considered a promising approach to translate proteomics to clinical assays with a diagnostic value. Several diseases, notably cancer, are associated with well documented deficiencies in the protein phosphorylation signaling networks. Consequently, several drug targets comprise the enzymes involved in this PTM processing i.e. kinases and phosphatases. Unfortunately, there is currently a lack of adequate tools for studying phospho-signaling networks, which hampers the development of effective diagnostics and treatment. This includes phosphopeptide specific antibodies which are either scarce or lack adequate performance. We here present a proof of concept demonstration showing that MIPs can capture phosphopeptides in a sequence specific manner in highly complex biomedia. This can in principle be translated into robust, low cost multiplex assays with a potential impact on clinical phosphoproteomics.