Quantitative reverse transcription polymerase chain reaction of the CENP-E gene segment followed by phosphor imaging densitometry evaluation. The polymerase chain reaction MIMIC® technique was used. (a) Significant upregulation in CENP-E in eight out of 12 rheumatoid arthritis synovial fibroblast cultures (white bars) as compared with all osteoarthritis fibroblast cultures (dotted bar; total n = 4); whereas four rheumatoid arthritis fibroblast populations did not show an upregulation in CENP-E upregulation (black bars). Values are shown as phosphor imager arbitrary units (PAU, mean ± standard error of the mean). Each MIMIC® was performed in quadruplicate. P < 0.05 was considered statistically significant. (b) Significant upregulation in six additional rheumatoid arthritis synovial fibroblast cultures (white bars) as compared with psoriatic arthritis fibroblasts (generous gift from E Märker-Herrmann, University of Mainz, Germany). Ratio of intensities are shown (when compared to standard 18S RNA).