TLR2- and MyD88-dependent and NLRP3 independent local cytokine production in synovium. (A) IL-1β mRNA expression and protein levels, IL-6 mRNA expression and protein (B), or keratinocyte-derived chemokine (KC) mRNA expression and protein (C), in biopsies isolated from synovial tissues from either wild-type (WT), TLR2-, MyD88-, NOD1-, NOD2-, RICK-, NLRP3-, ASC-, and caspase-1 gene-deficient mice. Four hours after intra-articular (i.a.) injection with 1 × 10^7 live B. burgdorferi. At least five animals per group, bars represent mean ± SEM; *P <0.05; **P <0.01; ***P <0.0001, Mann-Whitney U test, two-sided. (A-C Right panels) Four hours after i.a. injection of 1 × 10^7 live B. burgdorferi in 10 mL of PBS, patellae from five WT C57BL/6 mice or knockout mice were cultured for 1 h and IL-1β (A), IL-6 (B), and KC (C) levels were measured using Luminex. Data are represented as mean ± SEM; five animals in each group; **P <0.01, ***P <0.001; Mann-Whitney U test, two-tailed. ASC, apoptosis-associated speck-like protein containing a caspase recruitment domain (CARD); MyD88, myeloid differentiation factor 88; NLRP3, NOD-like receptor P3; NOD, nucleotide-binding oligomerization domain; RICK, serine-threonine protein kinase with a caspase activation and recruitment domain; TLR, Toll-like receptor.
Oosting et al. Arthritis Research & Therapy 2012 14:R247 doi:10.1186/ar4090