Increase in murine monoclonal-antibody-defined urinary antigens in patients with bladder cancer and benign urogenital disease.

Monoclonal antibodies (MAbs) were obtained from hybridoma clones established by cell fusion between P3X63Ag8.653 mouse myeloma cells and spleen cells of mice or rats hyperimmunized against human bladder cancer tissue or BC47 rat bladder cancer cells. RBS-31 and RBS-85 mouse MAbs and RBA-1 rat MAb were raised against BC47 cells and HBP-1 MAb was raised against human bladder cancer tissues. Urinary antigens detected by these MAbs were quantitatively assayed by means of ELISA using 50 microliters of 1:2 diluted urine samples. The cut-off value of the assay was set up as the mean + 4 X SD of the mean using data from the healthy individual urine samples. The reactivity of all healthy control urine samples were under the cut-off value (negative). By contrast, urine from bladder cancer patients reacted positively with the RBS-31 MAb at 72%, with the RBS-85 MAb at 63%, with the RBA-1 MAb at 51% and with the HBP-1 MAb at 35%. The urine samples from some patients with renal calculi, acute cystitis or complicated urinary tract infections showed only a weak reactivity with our MAbs. As for extra-bladder cancers, some patients with renal, renal pelvis, prostate or ureter cancer, but no patients with esophageal, gastric, colon or liver cancer or leukemia, had reactive urinary antigens.