Measurement of mRNA for the α chain of IL-2, IL-4, IL-7, IL-9, or IL-15 receptors in Th1 and Th2 clones. Columns represent mean values (+ SD) of mRNA levels detected by real-time quantitative RT-PCR on 8 Th1 and 9 Th2 clones, which were assessed before their testing in the suppressive assays. ^*P < .05.