Monoclonal antibodies: Uses in studies on vasopressin

The hybridomas have been used to produce monoclonal antibodies for the study of widely different substances. This chapter discusses a number of unexpected problems, particularly in the use of radioimmunoassay (RIA) techniques with the antibodies. Many different peptides have been identified in various vertebrates, although any given species generally has only two, a pressor or vasopressin (VP)-like peptide and a neutral or oxytocin (OT)-like peptide. Standard labeling techniques have also been modified, as have the related purification techniques, and RIAs have had to be highly optimized to detect these hormones in circulation. Monoclonal antibodies to VP and OT have been used in immunocytochemistry, radioimmunoassay, and for passive immunization in vivo. In all these applications, they have distinct advantages over conventional polyclonal antibodies. However, the small size of the neurohypophyseal hormones and the monospecificity of the antibodies require careful attention to details.