Affinity screening for weak monoclonal antibodies.

When selecting for monoclonal antibodies of a desired affinity, affinity chromatography can be a feasible alternative. This is of particular interest when low affinity monoclonal antibodies (dissociation constant (Kd) > 10(-4) M) are screened, as they are not easily recognised by traditional immunoassay procedures. In this study we have evaluated this approach by monitoring low affinity monoclonal antibodies on high performance liquid affinity chromatography columns with oligosaccharides, dinitrophenol and digoxin as immobilised antigen. Crude monoclonal antibodies in ascites or cell culture supematants, directed against these antigens, were retarded or adsorbed according to affinity or avidity on the antigen columns. Based on antibody retention, we were able to select hybridomas with the desired low affinity characteristics.