Comparison of a receptor binding assay with a radioimmunoassay for measuring human epidermal growth factor-urogastrone in urine

A radioreceptor assay for human epidermal growth factor-urogastrone (EGF-URO) employing mouse EGF-URO as tracer and calibration standards and human placental receptor as binding protein is compared with a radioimmunoassay for human EGF-URO. Results employing the receptor assay indicated similar values for urinary concentrations (1-16 nmol/l) for healthy control subjects and for patients with psoriasis. Lower values were obtained for bed-ridden patients with burns or patients recovering from orthopaedic surgery. The results obtained by radioimmunoassay were somewhat higher and correlated poorly (r = 0.5) with those obtained with the radioreceptor assay. The reason for this discrepancy is discussed.