QUANTITATIVE-ANALYSIS OF CYTOKINE MESSENGER-RNA EXPRESSION IN PERIPHERAL-BLOOD MONONUCLEAR-CELLS FOLLOWING TREATMENT WITH INTERLEUKIN-2

After activation with interleukin-2 (IL-2), peripheral blood mononucle ar cells (PBMC) have been reported to induce the expression of mRNA co ding various cytokines, including interleukin(IL)-1 alpha, -1 beta and tumor necrosis factor alpha (TNF alpha). We examined the cytokine mRN A expression of PBMC following treatment with IL-2 in vitro and in viv o by a quantitative method using the reverse transcription/polymerase chain reaction (RT-PCR). After stimulating PBMC with IL-2 in vitro, pe ak levels of IL-1 alpha mRNA were reached between 3 h and 12 h, and th ereafter declined. The IL-1 beta expression increased, with levels pea king at 1-6 h and, had decreased by 96 h. The expression of TNF alpha was elevated both 1-3 h and 24-48 h after stimulation. The peak levels of IL-1 alpha and -1 beta mRNA and the early elevation of TNF alpha m RNA mainly accounted for the cytokine mRNA expression in adherent cell s; however, the late induction of TNF alpha mRNA was observed in nonad herent cells. In patients with advanced carcinoma, the IL-1 alpha and -1 beta mRNA expression were elevated after IL-2 treatment for 5 conse cutive days, while the expression of TNF alpha mRNA also increased. Th ese results indicate that the quantitative RT-PCR method appears to be useful for analyzing the cytokine mRNA expression of PBMC after treat ment with IL-2.