Evaluation of long-term transport ability of a bioartificial renal tubule device using LLC-PK1 cells

Background. Haemodialysis therapy does not provide renal tubule function, such as active fluid and solute transport, nor metabolic or endocrine action. Moreover, this treatment is usually associated with serious complications and high mortality. We constructed a bloartificial renal tubule device by using renal tubule epithelial cells in an artificial membrane, and evaluated transport properties of the device for 2 weeks. Methods. A renal epithelial cell line, LLC-PK1 (Lewis-lung cancer porcine kidney), was seeded on polysulfone hollow fibres in small and large modules. We studied perfusion and leakage of urea nitrogen (UN) and creatinine (Cr), as well as reabsorption of water, glucose and sodium for a period of 2 weeks. Results. Cell-lined hollow fibre membranes significantly reduced the leakage of UN and Cr throughout the 2 week period. Reabsorption of water, glucose and sodium were adequate from days 3 to 10 and gradually decreased thereafter. LLC-PK1 cells actively transported these substances. Scanning electron microscopy revealed that cells in the hollow fibres on day 8 became completely confluent. However, they became multilayered and almost obstructed the hollow fibres on day 13. Conclusions. This bioartificial renal tubule device functioned to reabsorb water, glucose and sodium for similar to10 days. This is the first report of successful long-term evaluation of a bloartificial renal tubule device. This device, in combination with continuous haemo-filtration, may provide treatment to prevent complications of dialysis and raise the quality of life in chronic renal failure patients.