The influence of methods of production, purification and storage of monoclonal antibodies upon their observed specificities.

A panel of 38 monoclonal antibodies was exposed to a variety of physical conditions commonly used in their purification and storage. Reactivity with the homologous (immunising) antigen was reduced in a significant proportion (42%) of antibodies following these physical treatments. Sensitivity to particular physical treatments correlated with antibody subclass. In 3 cases the relative specificity of the antibody (as measured by cross-reactivity with 16 closely related antigens) was also altered. Following passage of the cloned hybridomas as ascites, 3 antibodies exhibited marked differences in specificity, which suggested the selection of different genotypes. The importance of documenting the methods of production, purification and storage of particular monoclonal antibodies used in comparative assay is stressed.