This Small Business Innovation Research (SBIR) Phase I project aims to develop a rapid and reliable method for inducing, detecting and recovering isotypic switch variants in hybridoma cell lines using in-vitro switching media, gel microdrop (GMD) technology and fluorescence activated cell sorting (FACS). Antibodies are widely used in research and clinical applications. Antibodies of the IgM subclass are generally considered the least useful due to their pentameric structure and lack of affinity for protein A and protein G which makes purification and modification of IgM antibodies difficult, and enzymatic digestion for Fab fragment production almost impossible. Many of the hybridomas produced, however, are of the IgM subclass. IgM producing hybridomas do, however, spontaneously switch the subclass of antibody they produce to IgG, although at very low frequencies. Currently there is no simple method for controlling class switching and isolating class switch variants. Several protocols have been developed to effect class switching of IgM producing hybridomas and to isolate class switch variants, but these procedures are lengthy and very labor-intensive involving multiple screening cycles. By providing a rapid method for isolating IgG switch variants, the GMD method will significantly improve bioprocessing of monoclonal antibodies for research and therapeutic use.
The commercial application of this project will be in the development of monoclonal antibody products for research, therapeutic, diagnostic and imaging purposes.
