Conclusion
Serum BAFF levels can be used as a surrogate marker of disease activity in sarcoidosis patients. Increased BAFF may be related to the pathogenesis of sarcoidosis.
Objective
The purpose of this study was to determine serum levels of B-cell-activating factor (BAFF) and its clinical association in patients with sarcoidosis.
Results
Serum BAFF levels were significantly elevated in sarcoidosis patients when compared with healthy controls. The frequency of skin and eye involvement was significantly higher in patients with elevated serum BAFF than in patients with normal levels. Serum BAFF levels were correlated with serum levels of ACE, lysozyme and IFN-γ. Immunostaining of anti-BAFF in the skin revealed BAFF expression by epithelioid cells of granuloma. In vitro, IFN-γ induced membrane-bound BAFF expression on monocytes and secretion of soluble BAFF by isolated monocytes. In the peripheral blood, sarcoidosis patients showed increased naïve B cells with a reciprocal decrease in memory B cells and plasmablasts. Seventeen of 26 (65%) sarcoidosis patients exhibited ANA positivity.