PT  - JOURNAL ARTICLE
AU  - CONSUELO M. LÓPEZ De PADILLA
AU  - KELLY T. McNALLAN
AU  - CYNTHIA S. CROWSON
AU  - HATICE BILGIC
AU  - RICHARD J. BRAM
AU  - MOLLY S. HEIN
AU  - STEVEN R. YTTERBERG
AU  - SHREYASEE AMIN
AU  - ERIK J. PETERSON
AU  - EMILY C. BAECHLER
AU  - ANN M. REED
TI  - BAFF Expression Correlates with Idiopathic Inflammatory Myopathy Disease Activity Measures and Autoantibodies
AID  - 10.3899/jrheum.120555
DP  - 2013 Mar 01
TA  - The Journal of Rheumatology
PG  - 294--302
VI  - 40
IP  - 3
4099  - http://www.jrheum.org/content/40/3/294.short
4100  - http://www.jrheum.org/content/40/3/294.full
SO  - J Rheumatol2013 Mar 01; 40
AB  - Objective. To investigate B cell survival cytokine messenger RNA (mRNA) levels as biomarkers of idiopathic inflammatory myopathies (IIM). Methods. We measured and compared mRNA levels of B cell survival cytokines by quantitative real-time polymerase chain reaction in 98 patients with IIM, 38 patients with systemic lupus erythematosus, and 21 healthy controls. The cytokines were B cell-activating factor belonging to the tumor necrosis factor family (BAFF); ΔBAFF; and a proliferation-inducing ligand (APRIL); and their receptors BAFF-R, transmembrane activator and calcium modulator and cyclophilin ligand interactor, and B cell maturation antigen (BCMA). We also identified autoantibodies, including anti-Sm, anti-RNP, anti-SSA/Ro, anti-SSB/La, anti-topoisomerase 1, anti-hystidyl-tRNA synthetase, anti-ribosomal P, and anti-chromatin. Clinical disease activity was assessed by the International Myositis Assessment and Clinical Studies core set tool. We examined correlation of mRNA with disease activity, medication use, and autoantibodies. Results. We found a positive correlation of BAFF and ΔBAFF expression with 3 disease activity measures, with ΔBAFF having a stronger correlation. Similarly, anti-SSA/Ro-52 and/or anti-SSA/Ro-60 had a strong positive correlation with mRNA levels of BAFF and ΔBAFF, and with relative ratios of BAFF/APRIL and BCMA/BAFF-R. Conclusion. These findings highlight the potential importance of BAFF, ΔBAFF, and BAFF-R in the pathogenesis of IIM, and suggest an important role in the assessment of disease activity.