BINDING STUDIES OF EPIDERMAL GROWTH FACTOR RECEPTOR TARGETED COMPOUNDS USING SURFACE PLASMON RESONANCE

• Main Author: Kankanala, Spandana
• Format: Others
• Published: VCU Scholars Compass 2009
• Subjects: Chemical Engineering; Engineering
• Online Access: http://scholarscompass.vcu.edu/etd/1737; http://scholarscompass.vcu.edu/cgi/viewcontent.cgi?article=2736&context=etd

The study of binding kinetics of proteins plays an important role in understanding molecular mechanisms that drive biological processes. The binding rate constants reflect the dynamics of the system and associated biological activity measurements of the association and dissociation rate constants make it possible to compare different interactions in a standardized manner and help elucidate a mechanistic understanding of binding events. In our study, we used Surface Plasmon Resonance (SPR) technology (Biacore) to study the binding kinetics of the antibodies EGF, Cetuximab and a candidate drug P-13 with the receptor EGFR. The candidate drug P-13 was synthesized and tested on Biacore for binding kinetics. This peptide is anticipated to bind to domain III of EGFR-ED. The study also compared the interaction kinetics of EGF/EGFR and Cetuximab/EGFR with the previous literature and a summary of results is produced. Our Biacore experiments on EGF/sEGFR suggest a two-state affinity binding with 90% high affinity binding sites, which compares with the previous studies in cells. The dissociation rate constant for Cetuximab/sEGFR interaction was reported for the first time using SPR while the other kinetic constants were comparable to literature. Although the peptide P-13 demonstrated a relatively weak (micro molar) binding capacity to the receptor, as compared with EGF and Cetuximab, the dissociation rate constant was comparable to a nano molar binder. Hence, we argue that the region of binding of P-13 is sterically inhibited as per the receptor orientation, which is consistent with the computer design data supplied with this candidate drug.