TLR4 and rheumatoid arthritis: With respect to mononuclear phagocytes from patients with RA, MDM differentiated with RMP-IC increased CD14, CCR2, and TLR4 expressions as well as IL-1β, IL-6, and TNF-α levels in supernatants but decreased HLA-DR and CD86 expressions compared with those differentiated with MDM-Unstim cells (Figures 1B–D, 2A,B).