Determinants of risk infection during therapy with anti TNF-alpha blocking agents in rheumatoid arthritis

The use of TNF-alpha antagonists (infliximab, etanercept, adalimumab) has changed the course of many rheumatic diseases including rheumatoid arthritis (RA). Since their approval, some questions regarding their safety including infections have been observed. The aim of the study was to evaluate the changes in cytokines levels and cells subsets in patients with RA during anti TNF blocking agents treatment and the possible effect on infections' development. We evaluated in 89 RA patients [39 treated with etanercept (ETN), 29 with adalimumab (ADA) and 21 with infliximab (IFN)] at baseline and after 6 months the following parameters: procalcitonin, ESR, CRP, cytokines as TNF, IL-6, IL-10, IL-8 and the TNF/IL-10 ratio, and peripheral mononuclear cells as CD3+, CD3+/CD4+, CD3+/CD8+, CD19+, CD3-/CD16+/56+, CD14+HLADR+, CD20+, CD19+/CD38+. Peripheral mononuclear cells were detected by flow cytometric system Cytomics FC500 and cytokines circulating levels by a quantitative sandwich enzyme immunoassay technique (Human IL-8 Instant ELISAe Bioscience, Human IL-6 Instant ELISA e Bioscience, Human IL-10 Instant ELISAe Bioscience and Human TNF-a Quantikine immunoassay RD system). A lower reduction of CD14+HLADR+ in ADA group 54.6±10.4% vs ETA 48.4±15.7% vs INF 40.7±16.5%, p<0.039 was found. No differences in all three groups on peripheral mononuclear cells CD3+, CD3+/CD4+, CD3+/CD8+, CD19+, CD 20+, CD19+/CD38+, CD3-/CD16+/56+, and cytokine circulating levels were found. The number of infections at 6 months was: 10.3% in ADA group, 12.8% in ETN group and 19.04% in IFN group. A correlation was found between the reduction in CD14+HLADR+ cells and IFN treatment. Our data showed that the level of CD14+HLADR+ cells was reduced during therapy with IFN. ADA and ETN don't reduce lymphocyte populations and their subsets such as CD14+HLADR+ cells that play an important role host defence.