Figure 4

Stimulatory activity of AREG on cytokine production by RA-FLS. (A) Effects of AREG on cytokine expression in RA-FLS. Four RA-FLS lines were cultured with the indicated concentrations of recombinant human AREG and/or genistein. After 4 h of stimulation, total RNAs were extracted and the mRNA levels of PDGF, bFGF, VEGF, IL-1β, IL-6, IL-8, TNF-α and GM-CSF were measured by real-time PCR. The results for VEGF, IL-8, GM-CSF and IL-6 are shown. The results for the other molecules were omitted from the figure, since AREG had no effect on their expressions. (B) Effects of AREG on cytokine production by RA-FLS. Four RA-FLS lines were cultured with the indicated concentrations of AREG for 24 h. The GM-CSF, IL-6, IL-8 and VEGF concentrations in the supernatants were measured by ELISA, and are shown as means ± SD. (C) Effects of AREG on the expression of sheddases. The same cDNA samples used in panel A were subjected to real-time PCR analysis for ADAM10 and ADAM17. The results for ADAM10 were omitted from the figure, since they were similar to those for ADAM17. Each panel shows a representative result of three independent experiments. Significant differences from unstimulated cells are shown by asterisks (*P < 0.05; **P < 0.01).