This result indicated that the number of CD68-positive sublining macrophages which had been previously shown to be positive for MRP [39] was a sensitive biomarker to measure clinical responses to effective therapies in RA clinical trials, but not for the interventions which were ineffective (anti-MCP-1, SRM, 0.19; anti-C5aR, SRM, -0.071). Here, C5AR1 is linked to rheumatoid arthritis.