When B lymphocytes from RA patients were selected based on their memory (CD27+) or naïve (CD27–) phenotype, SF B cells expressed consistently lower levels of CXCR5, CXCR7 and CCR6 and higher CXCR4 levels compared to PB regardless of their prior contact with the antigen. This evidence concerns the gene CXCR4 and rheumatoid arthritis.