Although several reports have covered the effects of single or a combination of selected cytokines on SFB and their influence on RA pathogenesis (reviewed in [22]), SFB gene expression in response to 4 disease-relevant stimuli (IL-1 β, TNF- α, TGF- β, and PDGF-D) and the subsequent inference of GRNs have not been addressed to date. This evidence concerns the gene PDGFD and rheumatoid arthritis.