Figure 2
Differential expression of type I interferon (IFN)-response gene activity in relation to clinical responder status to RTX. The expression levels of eight IRGs (LY6E, HERC5, IFI44L, ISG15, MxA, MxB, EPSTI1 and RSAD2) were determined by quantitative (q)PCR analysis in peripheral blood cells of patients with RA before RTX treatment. Average expression in Log2 of the eight IRGs was calculated and used as IFN-score. Data are shown as box plots; each box shows the 25th to 75th percentiles. Student t test analysis revealed a significantly higher IFN-score in non-responders compared to responders based on ΔDAS28 (P = 0.0074) (A), and EULAR good/intermediate responders (1, 2) versus non-responders (0) (P = 0.0599) (B). PCR, polymerase chain reaction.