FIGURE 2.
CTLA-4 transcription is rapidly increased after stimulation. RNA analysis of CTLA-4 expression in freshly isolated human PBMCs. PBMCs were isolated and stimulated with PMA/A23187 for the indicated times. Total RNA was isolated as described in Materials and Methods. a, CTLA-4 levels as determined by RT-PCR and PCR products visualized on ethidium bromide-stained agarose gel. Results are representative of three independent experiments. b, CTLA-4 expression measured by quantitative PCR. Real-time PCR was performed as described in Materials and Methods and the results represent average induction in PBMCs from 15 normal volunteers.