In TLR2-/- mice, synovial infiltrate was significantly decreased in comparison with TLR2+/+ mice (4.9 ± 0.33 in TLR2+/+ mice [n = 15] versus 3.1 ± 0.67 in TLR2-/- mice [n = 12] on day 25 after arthritis onset; P < 0.045). Here, TLR2 is linked to Arthritis.