Infliximab reduces CD147, MMP-3, and MMP-9 expression in peripheral blood monocytes in patients with active rheumatoid arthritis

Recent studies have reported elevated expression levels in active rheumatoid arthritis patients of the cluster of differentiation (CD) 147 on CD14+ peripheral blood monocytes and as a result, CD147 may be a target for the development of a novel rheumatoid arthritis therapy. This report describes the inhibitory effects of infliximab on CD147 and metalloproteinases (MMP)-3 and MMP-9 overexpression in peripheral blood monocytes obtained from patients with active rheumatoid arthritis. Thirty patients with active rheumatoid arthritis that were refractory to methotrexate therapy were randomized at a 4:1 ratio into groups A and B, respectively. Group A received three to four infusions of infliximab (3 mg/kg) and group B participants received four infusions of placebo. Both groups were also treated with a stable background dose of methotrexate. The CD147 expression levels on CD14+ peripheral blood monocytes of rheumatoid arthritis patients was detected by flow cytometry. The expression of CD147, MMP-3, and, MMP-9 mRNA in peripheral blood mononuclear cells was assayed by real-time quantitative PCR, and the expression of MMP-3 and MMP-9 in serum was measured by a multiplexed microsphere-based flow assay. Results showed that the expression of CD147 and MMP-9 mRNA in group A decreased compared to group B. Expression of CD147 on CD14+ monocytes was reduced (P<0.05), and serum MMP-3 and -9 levels in group A were decreased by week 18. These data suggested that infliximab could inhibit CD147 expression on CD14+ monocytes as well as reduce the levels of MMP-3 and MMP-9 in peripheral blood monocytes.