IL-6, IL-8 and TNF production by cytokine and lipopolysaccharide-stimulated human renal cortical epithelial cells in vitro.

The capacity of renal epithelial cells to produce IL-6, IL-8 and TNF was investigated. Cultures of explanted human renal cortical epithelial cells (RCEC) were established, and cytokine-release and mRNA expression by these cells were measured. IL-6, IL-8 and TNF release were measured after stimulation with IL-1 beta TNF-alpha, LPS and the phorbol esther PMA. All these agents were found to induce increased release of the three cytokines. Whilst no spontaneous TNF-release occurred, IL-6 and IL-8 were continuously released by non-stimulated RCEC cultures. IL-1 beta was the most potent trigger, enhancing both RCEC cytokine release and expression of IL-6, IL-8 and TNF mRNA. Indomethacin, budesonide, cyclosporin and FK 506 were tested for their influence on RCEC cytokine release. Only the steroid budesonide appeared to reduce both spontaneous and IL-1 beta induced cytokine release. Our data demonstrate stimulus specific release of IL-6, IL-8 and TNF by RCEC, and suggest that cytokine cell-to-cell communication may be important in regulating inflammatory processes in the kidney.