Validation of gene array results by Real Time RT-PCR. Genes selected for validation by Real Time RT-PCR in CECs before (bar 1) and after (bar 2) iloprost infusion in SSc patients without (panel A) and with (panel B) digital ulcers. ICAM-1, Bcl2 and VEGF transcripts were increased several times after iloprost infusion in both groups of patients. The increase was statistically significant (P < 0.05) in all cases. The experiments were carried out in triplicates.