(A) Expression of bFGF-specific mRNA. PBMC from HDs (n = 4) and patients suffering from HCL (n = 4) were subjected to RNA isolation immediately after separation by gradient centrifugation. After RT-PCR amplification using bFGF-specific primers and Southern blotting, positive reactions were visualized by hybridization with a DIG-labeled bFGF cDNA probe followed by autoradiography. Negative control: no cDNA added; K562 mRNA served as positive control. In parallel experiments, β-actin expression was analyzed by RT-PCR to ensure that identical amounts of cDNA are used (not shown). (B) Synthesis of bFGF protein. PBMC derived from HCL patients (n = 3) and HD (n = 3) were analyzed for intracellular bFGF. A total of 2 × 10⁶ cells were lysed and bFGF was determined by ELISA. Data are shown as mean values (HD, 7 pg/mL; HCL, 420 pg/mL). (C) Activation of bFGF-specific mRNA. PBMC from HDs (n = 2) and HCL patients (n = 2) were cultured for 48 hours in medium or stimulated with either PWM (10 μg/mL) or TPA (10 ng/mL) + Ca-Ip A23187 (10 ng/mL) (TPA+Ca-Ip). After RNA isolation, RT-PCR, Southern blotting, and hybridization with a DIG-labeled bFGF, cDNA-positive reactions were visualized by autoradiography (a). K562 mRNA served as positive control. (b) Shows results of β-actin–specific RT-PCR.