Regeneration of peritoneal effluent by Madin–Darby canine kidney cells-lined hollow fibers

Regeneration of plasma ultrafiltrate is a significant step towards the development of wearable artificial kidneys (WAK). Monolayers of Madin–Darby canine kidney (MDCK) cells were grown on inner surface of cellulose diacetate hollow fibers contained in mini-filters. Eight such devices were tested as bioartificial tubules for regeneration of peritoneal dialysis effluent (PD drainage) from a patient. PD drainage was perfused at a rate of 25 μl min−1, under 50 mm Hg hydraulic pressure and ultrafiltrate was produced from apical to basal direction of the cells. Cell-uncovered membranes (n=8) were also similarly tested as controls. Hydraulic permeability of the cell-uncovered membranes was 0.49±0.06 μl min−1, whereas that of the cell-covered membranes (experimental) was 0.28±0.04 μl min−1 (P<0.0001). Concentrations of sodium, chloride and potassium in the filtrate through the cell-covered membranes were 21.3±11.6, 17.8±13.8 and 0.56±0.14 mEq l−1, respectively, in comparison, across cell-uncovered membranes (control), 137.9±3.3, 104.5±1.1 and 2.53±0.18 mEq l−1, respectively (P<0.0001, experimental vs. control). Urea nitrogen, creatinine, uric acid and glucose concentrations were 5.4±4.5, 0.81±0.66, 0.85±0.47 and 137.5±134.3 mg dl−1, respectively, in the filtrate across the cell-covered membranes, and 49.1±4.9, 7.06±0.60, 4.26±0.47 and 1098.1±147.4 mg dl−1, respectively, in the filtrate across the cell-uncovered membranes (P<0.0001). In conclusion, MDCK cell-covered membranes used in this study removed electrolytes, glucose and uremic metabolites significantly from the PD drainage from a patient. Thus, such a device has potential for use in the development of a WAK.