Monoclonal antibodies as physiologic probes

This report covers four independent studies exploring biomedical applications of monoclonal antibodies. The anti-digoxin hybridoma system illustrates: (1) a series of different monoclonal antibodies to a simple hapten can serve as a model system for studying the fine specificity of the antigen-antibody combining site; (2) high-affinity monoclonal antibody can serve as a reliable reagent in a clinical assay for the determination of drug levels such as digoxin in patients' sera; and (3) Fab prepared from monoclonal anti-digoxin antibody may serve as a therapeutic drug for the reversal of digoxin intoxication. Monoclonal anti-mullerian inhibiting substance (anti-MIS) antibody will facilitate the purification of MIS by affinity chromatography. Monoclonal anti-MIS antibodies will aid in the detection of both the site of cellular production of MIS and the receptors for MIS; will allow the development of a clinically useful RIA for the detection of MIS in tissue extracts, serum, and urine; and will serve as physiologic probes in the study of the potential role of MIS as a chemotherapeutic reagent. The high degree of specificity by the monoclonal anti-thyroid stimulating hormone antibody (hTSH) should allow for studies on structure/function relationships, detection, and analysis of hTSH or hTSH-beta in the presence of other human glycoprotein hormones. The reduced affinity of anti-hTSH-beta 1/1 together with its specificity should permit the purification of hTSH or hTSH-beta by affinity chromatography. Another application is the use of the antibody as an immunofluorescent probe for hTSH-producing cells in the anterior pituitary