Fig. 2

Intra articular injection of S100A8 leads to local induction of monocytes in the synovium. a-f mRNA expression of monocyte marker Ly6C (a), macrophage marker F4/80 (B), Ly6C^high chemokine CCL2 (c), and Ly6C^high chemokine receptor CCR2 (d) are increased in the synovium of mice 24 h after intra articular injection with S100A8, compared to BSA-injected controls, whereas Ly6C^low chemokine CX3CL1 (e), and Ly6C^low chemokine receptor CX3CR1 (f) are not affected after S100A8 administration, as analyzed using RT-qPCR. Data represent mean ± SD of six individual mice. *Significantly different from treated control (*p < 0.05). g, h HE staining on histological sections of the joint 24 h after intra-articular (i.a.) injection with S100A8 demonstrated strong presence of inflammatory cells with monocyte-like morphology in the synovial lining layer of the knee joints (g), whereas BSA injection as control resulted in less pronounced presence of inflammatory cells (h). Ct cycle threshold