FOLR2+ICAM1+ macrophages are proportionally enriched in healthy synovial tissue compared to RA and are characterized by many pro-inflammatory cytokines and chemokines such as CCL4, TNF, and IL-1B, indicating that they may form the first line of innate defense against pathogens in the synovial joint. The gene discussed is CCL4; the disease is rheumatoid arthritis.