Circulating concentrations of soluble interleukin 6 receptors gp80 and gp130 in chronic renal failure and effects of renal replacement therapy

Background: Circulating receptors modulate the biological effects of cytoki nes. Renal insufficiency is known to influence the concentrations of the so luble tumor necrosis factor (TNF) receptors p55 and p75. No data are availa ble on the concentrations of the circulating interleukin 6 (IL-6) receptors gp80 and gp130 during chronic renal insufficiency. Methods: We compared th e serum concentrations of the IL-6 receptors gp80 and gp130 to those of the TNF receptors p55 and p75 in end-stage chronic renal failure, continuous a mbulatory peritoneal dialysis, and hemodialysis (HD). Results: In healthy c ontrols the concentrations of gp80, gp130, p55, and p75 in serum were 82.1 +/- 24.3, 87.9 +/- 20.2, 1.1 +/- 0.2, and 1.7 +/- 0.3 ng/ml, respectively. These concentrations were increased to, respectively, 112.2 +/- 18.0, 186.0 +/- 37.7, 10.5 +/- 4.3, and 15.0 +/- 7.5 ng/ml in chronic renal failure, t o 138.8 +/- 18.0, 181.3 +/- 46.1, 25.5 +/- 5.2, and 19.1 +/- 3.4 ng/ml in c ontinuous ambulatory peritoneal dialysis, and to 107.9 +/- 29.4, 146.6 +/- 30.5, 22.9 +/- 6.3, and 16.8 +/- 6.0 ng/mi in HD (before dialysis session). The concentrations after HD were higher for p75 only. Conclusions: The dat a show that the concentrations of the IL-6 receptors (gp80 and gp130) are e levated in chronic renal insufficiency. The increase is relatively low as c ompared with the elevation of the TNF receptors in this situation. HD does not result in a consistent change in serum concentrations of the various re ceptors. Copyright (C) 1999 S. Karger AG, Basel.