Expression of BAFF receptors in muscle tissue of myositis patients with anti-Jo-1 or anti-Ro52/anti-Ro60 autoantibodies
Abstract
Anti-Jo-1 and anti-Ro52 autoantibodies are common in patients with myositis. Survival of autoantibody-producing cells is dependent on B-cell-activating factor of the tumour necrosis factor family (BAFF).
BAFF levels are elevated in serum of anti-Jo-1-positive myositis patients and are influenced by type-I interferon (IFN). IFN-producing cells and BAFF mRNA expression are present in myositis muscle.
We have investigated expression of the receptors for BAFF in muscle tissue and found their association to serum autoantibodies and muscle expression of type-I IFN markers. The expression pattern of receptors for BAFF on B and plasma cells in muscle suggests a possible local role for BAFF in autoantibody production in muscle tissues of patients with myositis who have anti-Jo-1 or anti-Ro52/anti-Ro60 autoantibodies.