Proximity (ProxiMol) and Step-Back Selections

Abstract

Other chapters in this volume describe the selection of antibodies specific to cell surface molecules in a non-guided manner. Cell surfaces are antigenically complex and this results in difficulties in specifically selecting antibodies which bind to a given cell surface molecule without selecting for a host of unwanted specificities in parallel. The desired antigen specificity can in many cases be obtained, but only after an intensive screening programme has been undertaken. One of the rationales for the development of ProxiMol selection (previously known as Pathfinder selection) was to provide an efficient method for the generation of a population of antibodies enriched for binders which bind in close proximity to a particular desired cell surface antigen alleviating the necessity for labour intensive screening programmes. This selection regime greatly narrows the scope of the selection and increases the probability of selecting antibodies of interest.