Cytokine production by peripheral blood mononuclear cells from pediatric chronic peritoneal dialysis patients

Previous reports have documented impaired cytokine production by peritoneal macrophages in chronic peritoneal dialysis (CPD) patients. To determine if this observed defect was a reflection of systemic mononuclear cell dysfunction, the function of peripheral blood mononuclear cells obtained from pediatric patients on CPD was assessed after stimulation with lipopolysaccharide (LPS). Levels of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) mRNA and protein were measured before and after stimulation with LPS. There was no significant difference in the response of mononuclear cells from CPD patients and normal controls in terms of increase in TNF-α mRNA [median stimulation index (SI) = 6.6 vs. 3.7, P= 0.35] or IL-1β mRNA (median SI = 6.2 vs. 6.5, P= 1.0). There was also no significant difference between the median increase in TNF-α protein secretion (median 372 pg/ml vs. 373 pg/ml, P = 0.60). These results suggest that systemic mononuclear cell function may be intact in CPD patients, and therefore this does not account for the dysfunction of peritoneal macrophages that has been previously reported.