CD14 and rheumatoid arthritis: Although not examined in our study, expanded CD14+CD16+ monocytes in RA may result in an increased responsiveness to immune complex(IC)-stimulation (60). Given that IgG-containing immune complexes (IC) including those containing rheumatoid factors (RFs) and cyclic citrullinated peptide (CCP) autoantibodies are found abundantly in serum and synovial fluid of patients with RA, it could be one potential pathophysiological role of intermediate CD14+CD16+ monocytes in RA.