Monitoring of the serum biomarkers during the therapy period of the patients with rheumatoid arthritis. Pilot Study
Abstract
Aims: To evaluate the possibility of monitoring the effect of anti TNFa therapy in patients with active rheumatoid arthritis by multiplex assessment of serum levels of different biomarkers which reflects underlying pathogenic mechanisms and activity of this disease. Methods: A group of 23 patients with active rheumatoid arthritis, 20 female, 3 male, average age 48.6 years +- 10.3, average weight 68,5 +- 13 kg was evaluated prior therapy and after 14-16 weeks of therapy with TNFa blocking agent adalimumab 40 mg subcutaneously every two weeks (No = 21) and etanercept 25 mg subcutaneously twice weekly (No = 2).
Of 23 patients, 16 (70 %) of subject were treated concomitantly with glucocorticoids (GC), and 19 subject (84 %) with methotrexate. The blood was collected by venipunc- ture using Vacuette collection tubes (Greiner Bio-One, Austria).
The blood samples were centrifuged at 640 g for 10 min, serum was aliquoted and stored until analysed in freezer at -75 oC. Serum levels of six parameters: IL 1β, IL10, IL6, VEGF, MMP9 and adiponectin were assessed by multiplex immunoanalysis using xMAP technology with commercially available multiplex kits Human Cardiovascular 1 panel and Human Cytokines-Chemokines panel, both from Linco Research (USA) according to manufacturer's instructions for use.
The analysis was performed on Luminex 100 instrument and data analysis on Luminex 100 IS software version 2.3. These parameters were correlated with blood levels of CRP, PCT, TK (assessed by traditional immunoassays), patient weight and DAS-2828.
For all parameters there was counted average, median, standard deviation, minimal and maximal values from results prior and after therapy. Furthermore, data were analysed by Wilcoxon pair test and Rank-order correlation.