Report of the National Pituitary Agency Collaborative Study on the Radioimmunoassay of FSH and LH¹

THE NATIONAL Pituitary Agency (NPA) has conducted a collaborative study of the radioimmunoassay of human follicle stimulating hormone (HFSH) and human luteinizmg hormone (HLH) in order to characterize and make available the necessary reagents for use in clinical investigation. Before suitable reagents can be distributed for clinical investigation, three conditions must be defined: 1) specificity of the antisera, evaluated by comparison of the results obtained from the radioimmunoassay technique and those obtained from the bioassay technique, 2) the applicability of the radioimmunoassay technique to measurements in serum, 3) the designation, establishment and availability of suitable standards for the expression of the radioimmunoassay results. Several groups of investigators collaborated in an attempt to define these three conditions. Four human pituitary gland extracts differing widely in FSH/LH ratio and “immunochemical grade” HFSH and HLH were prepared by L. E. Reichert (LER series); a second “immunochemical grade” HLH was prepared by A. F. Parlow (AFP series).