IL-6 mRNA synthesis by peripheral blood mononuclear cells (PBMC) in patients with chronic renal failure.

Abstract

We measured levels of IL-6 mRNA in PBMC obtained from patients with chronic renal failure, using polymerase chain reaction (PCR). PBMC were isolated from 45 patients on haemodialysis (HD) at the start of HD. PBMC were also isolated from 35 patients on HD at the end of HD, 23 patients on continuous ambulatory peritoneal dialysis (CAPD), 24 undialysed patients with chronic renal failure (CRF), and 19 healthy controls. Total RNA was extracted from PBMC with RNA zol and reverse transcribed into cDNA. To prepare samples containing identical amounts of beta-actin cDNA, we performed competitive PCR by co-amplifying serial dilutions of mutant templates containing a single point mutation which generated a unique Eco RI site. Next, to measure IL-6 cDNA semiquantitatively in the samples containing identical amounts of beta-actin (100 pg), we performed PCR amplification using 2 fg of the IL-6 mutant template containing a unique Eco RI site. Higher levels of IL-6 mRNA in the PBMC were observed in the HD patients than in the CAPD patients and healthy controls. The levels of IL-6 mRNA in the PBMC at the end of HD were not significantly higher than those at the start of HD. These results suggest that the dialysis session itself did not significantly affect IL-6 mRNA levels in the PBMC, but that chronic stimulation by maintenance HD may be associated with higher levels of IL-6 mRNA observed in HD patients.