Figure 1

TLR4 promotes antibody-induced arthritis. (A) Toll-like receptor (TLR)4 transcript levels were measured in the ankle joint tissues of wild type (WT) mice 0, 3, 5, 7, 8, 9 and 10 days after K/BxN serum injection (100 μL, twice) by real-time PCR (n = 5). (B) Levels of transcription of endogenous TLR4 ligands were estimated in the ankle joint tissues of WT mice zero and seven days after K/BxN serum transfer (100 μL, twice) by real-time PCR (n = 4). (C) Ankle thickness and clinical scores were measured in WT and TLR4^-/- mice, some of which had been injected with LPS, after K/BxN serum transfer (100 μL, twice) (n = 6). (D) Gross and histological examination of ankle joints in WT and TLR4^-/- mice seven days after serum transfer (n = 3), which was scored. (E) Ankle thickness and clinical scores were measured in WT mice, some of which had been injected with LPS, after K/BxN serum transfer (150 μL of serum, twice) (n = 5). The results shown are representative of three repeated independent experiments. n.s., not significant; * P < 0.05, ** P < 0.01, *** P < 0.001.