Expression of IL-7 mRNA. Expression in normal and CTCL skin (A) and in normal keratinocytes and fibroblasts (B) was analyzed by quantitative PCR. The data are shown as a relative quantification of IL-7 mRNA expression levels divided by levels of β-actin mRNA. Expression of IL-7 mRNA was significantly higher in CTCL skin lesions than in samples of normal skin (A). ^*P < .001.