An in vitro biocompatibility evaluation of double-J stents.

OBJECTIVES

For several years, studies performed to estimate in vitro biocompatibility of urinary catheters have been carried out using permanent cell lines. However, for a rational design of the testing procedure, the cell culture model should depend on the material application. We assess the biocompatibility of 13 double-J stents using an in vitro model of normal human urothelial cells (HUC). This article aims to mimic in vitro, on HUC monolayers, the close contact existing in vivo between the urothelium and double-J stents and to evaluate the subsequent effect on these cells.

METHODS

Fragments of each stent were deposited into the wells containing confluent HUC, with close contact maintained between the material and the cells. The same procedure with either no material or fragments of latex catheter was undertaken to provide the negative and positive controls, respectively. The contact was maintained for 1, 3, and 8 days. At the end of the incubation period, fragments of stent were removed and cell activity tests were performed (neutral red assay, MTT assay, and cell proliferation).

RESULTS

One of the silicone stents is significantly deleterious on HUC as determined by three tests after 8 days of contact. For two copolymers, a tendency to increase cell proliferation was noted. Concerning polyurethanes, we observed significant decreases in HUC viability and cell metabolic activity for five stents after 8 days of contact. All seven polyurethane stents significantly inhibited cell proliferation.

CONCLUSIONS

The HUC culture model may be of relevance for the screening of materials intended for use as double-J stents.