Regulation of interleukin-2 and interferon-γ gene expression in renal failure

Regulated expression of interleukin-2 (IL-2) and interferon-γ (IFN-γ) genes, induced in cultured peripheral blood mononuclear cells from patients with end-stage renal disease on hemodialysis (HD; N = 13) or peritoneal dialysis (PD; N = 13), was compared to that of 32 normal donors. Culture conditions were chosen that measure the transient, phytohemagglutinin-induced expression of IL-2 and IFN-γ messenger RNA (mRNA), as well the intactness of post-transcriptional and suppressor T cell-dependent mechanisms that control this expression. The latter was achieved by analyzing the superinduction of IL-2 and IFN-γ mRNA occurring upon culture with cycloheximide or after low-dose γ-irradiation, respectively. HD subjects showed a complete loss of inducibility of the IL-2 gene, concomitant with decreased inducibility of IFN-γ mRNA. In PD subjects, by contrast, expression of IL-2 mRNA was as vigorous as in normal donors, while IFN-γ mRNA was even more strongly inducible. This difference in gene inducibility is caused by a lack of T cell function in HD subjects. The defect in IL-2 gene expression in HD subjects, occurring most likely at transcription, may underly their impaired immune function.