Background BLyS is a novel TNF family ligand, mainly secreted by myeloid cellsandsynovial fibroblasts that exerts profound effects on B cells leading to their maturation and increased survival. Local expression of BLyS in inflamed joints from Rheumatoid Arthritis (RA) patients may contribute to the development and progression of disease.
Objectives We evaluated local gene expression of BLyS in RA patients with disease activity.
Methods Synovial fluids and Peripherical Blood (PB) were obtained from RA patients and were classified in two groups, Group I: RA evaluated by DAS 28 score as high disease activity (n=10, 7F/3M, age: 56,3 ± 20,9, range: 17-84) and Group II: Osteoarthritis (OA, n=18, 13F/5M, age: 70,5 ± 6,6, range: 58-86). Levels of BLyS expression were evaluated using Quantitative Real Time PCR (QPCR). All amplifications were carried out in duplicate and threshold cycle (Ct) scores were averaged for calculations of relative expression values. The Ct scores were normalized against Ct scores by subtracting the corresponding β2Microglobuline (β2M) control, or ΔCt=Ct,gene- Ct,B2M. To test for differential gene expression between groups, a two sample t-test was performed to compare the ΔCt in the two groups.
Results BLyS gene expression is shown in Table 1.
Conclusions Increased BLyS expression in active RA SF can be linked to B cell activation and proliferation in RA synovium.
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Disclosure of Interest None Declared