CXCL13 and rheumatoid arthritis: RA patients were then classified into four groups (high CXCL10/high CXCL13, high CXCL10/low CXCL13, low CXCL10/highCXCL13, low CXCL10/low CXCL13) based on baseline CXCL10 and CXCL13 cutoffs defined by their median values (260 pg/ml and 50 pg/ml respectively), and their response to TNF inhibitor therapy was compared.