Comparative study on the level of B lymphocyte stimulator ( Bly S) and frequency of lymphocytes between sero-negative and sero-positive rheumatoid arthritis patients.

Aim To investigate the differences of B lymphocyte stimulator ( Bly S) level and frequency of lymphocytes between sero-negative and sero-positive rheumatoid arthritis ( RA) patients. Methods Sixty-nine RA patients were enrolled into this study and their clinical data were recorded. The Bly S levels in plasma, frequency of T and B lymphocytes, as well as T-helper ( Th) subgroups were compared between sero-negative and sero-positive RA patients. Furthermore, the correlations between clinical features and immunological features were analyzed. Results The plasma Bly S level in sero-negative RA was higher compared to the sero-positive RA patients (1.73 ± 1.71 vs. 0.99 ± 0.59 ng/mL, P < 0.05) and osteoarthritis ( OA) patients (1.73 ± 1.71 vs. 0.59 ± 0.12 ng/mL, P < 0.05). Plasma Bly S level was correlated with disease activity score ( DAS-28, erythrocyte sedimentation rate and C-reactive protein), but had no correlation with the titers of rheumatoid factor and anti-cyclic citrullinated peptide (anti- CCP) antibodies. The patients with more advanced changes in X-rays had high plasma Bly S levels. No significant differences in the frequency of T lymphocytes, Th subpopulations and B lymphocytes in peripheral blood were observed between sero-negative and sero-positive RA patients. Conclusions Plasma Bly S level was correlated with disease activity and radiological progress, which indicates that plasma Bly S level may become a useful biological marker to reflect DAS and to predict RA prognosis. [ABSTRACT FROM AUTHOR]