Characterization of self-assembled monolayers (SAM) of peptide mimotopes of CD20 antigen and their binding with rituximab (R) using Quartz Crystal Microbalance (QCM) Piezo-Immunosensors: A novel technique to study CD20 antigen interaction.

e14004Background: CD20 antigen is an established target for antibody therapy like R. Understanding interactions of CD20 antigens is important for developing better agents and overcoming resistance. We have developed a new innovative biosensor based quantitative technique to study real time interaction of CD20 antigens with R using QCM Piezo-immunosensor, which can be used to characterize cell surface antigen, study interactions and understand mechanisms of resistance. Methods: Binding of R with SAM of peptide mimotopes of CD20 antigen was systematically characterized. Four peptide mimotopes of CD 20 antigen were selected from literature and redesigned to allow their SAM immobilizations on gold electrodes through a peptide linker with cysteine. The bindings of these peptides with R and control antibodies (Trastuzumab, Bevacizumab) were characterized by Quartz Crystal Microbalance (QCM). Among the four peptide mimotopes initially selected, the peptide designated as CN-14 was the most selective and sensitive...