TLR2 and rheumatoid arthritis: In human RA synovial tissue, which contains Mɸ expressing elevated TLR2 and TLR4 [5], TLR2 and TLR4 signaling contributed to the increased expression of inflammatory mediators and dominant negative MyD88 expression was shown to reduce TNFα, IL-6 and VEGF expression, without effecting IL-1β expression [49].