The in vitro cytotoxicity of urine from patients with interstitial cystitis.

Urine from patients with interstitial cystitis has been reported to be more cytotoxic than urine from healthy subjects when tested in vitro against cells from a normal urothelial cell line. The purpose of the present study was to develop a method to measure urinary cytotoxicity and so make it possible to estimate the toxicity of urine from interstitial cystitis patients. The study included 10 women with interstitial cystitis and 10 healthy controls. Urine specimens were obtained from both groups and urine cytotoxicity was measured by a modified 51Cr-release assay: A range of urine dilutions was added to suspensions of target cells with intracellular bound 51Cr, and cellular death was recorded by measuring the 51Cr-release from the target cells. The transitional cell bladder cell lines T24 and Hu609 and the erythroleukemia K562 cell line were used as target cells. There was no difference in urine cytotoxicity between interstitial cystitis patients and healthy controls. Urine cytotoxicity was increased by dilution in both groups.