Résumé
Oligonucleotide aptamers obtained using the SELEX procedure can recognize different molecules with high affinity. However, for proteins, this recognition is limited to native conformations and the specificity has not been clearly demonstrated by methods such as Western blotting, immunohistochemistry or immunoprecipitations. Using a library of oligonucleotides and a selection strategy based on high specificity instead of high affinity, we have reported previously the preparation of polyclonal oligobodies, reagents that recognize the protein PP2A in a very specific way. Here we report a method to obtain monoclonal oligobodies. The oligobody developed specifically recognized both native and denatured states of the protein CPD1 used as a model system. We further demonstrate the specificity of the monoclonal oligobody using Western blots, immunohistochemistry, and immunoprecipitation, procedures previously limited only to antibody-based detection. In addition, a confocal microscopy is shown that was obtained using an oligobody made by chemical synthesis using an oligonucleotide synthesizer, being this the first [quot ]synthetic antibody[quot ] reported.