These phenotypic characterizations of RA patients implicate CD1c+ DC2 and CD163+ DC3 in the systemic autoimmune disease rheumatoid arthritis and suggest that increased HLA-DR+ phenotypes with shared granulocytic and dendritic cell features can contribute to RA, potentially by providing enhanced co-stimulatory presentation of self-antigen(s) to CD4+ T lymphocytes. This evidence concerns the gene CD1C and rheumatoid arthritis.