Optimization of automated synthesis of affibodies and in vitro binding evaluation

Sammanfattning

Affibodies belong to a continuously developing field of biotechnological therapeutics. The affibody ZHER2:S1 binds to the receptor HER2, which is commonly over-expressed in some cancers. Varying this affibody using recombination has some limitations as there might be restrictions concerning peptides that does not occur naturally. This could possibly be solved using Solid Phase Peptide Synthesis. This is a process that uses chemical compounds to couple amino acids into peptides while strung to resin beads. That enables the production of tailor-made affibodies. This report examines the challenges and possibilities of designing a protocol to produce ZHER2:S1 using Solid Phase Peptide Synthesis. In the time available we were able to synthesize the first helix which is constant in all affibodies. This was only confirmed by MALDI-tof as there was not enough time to purify and analyze the peptide. We then used the similar pre-made affibody ZHER2:342 to examine its binding to the HER2 receptor. This was done using fluorescence microscopy on the cell lines SKOV3 and MCF-7.