RT Journal Article SR Electronic T1 BAFF (B cell activating factor) transcript level in peripheral blood of patients with SLE is associated with same-day disease activity as well as global activity over the next year JF Lupus Science & Medicine FD Lupus Foundation of America SP e000063 DO 10.1136/lupus-2014-000063 VO 2 IS 1 A1 Eric Zollars A1 Jadwiga Bienkowska A1 Julie Czerkowicz A1 Norm Allaire A1 Ann M Ranger A1 Laurence Magder A1 Michelle Petri YR 2015 UL http://lupus.bmj.com/content/2/1/e000063.abstract AB Objectives Quantitating gene expression is a potential method of developing biomarkers in systemic lupus erythematosus (SLE). Because of the known pathological role of B cell activating factor (BAFF) in SLE, we explored the association between BAFF gene expression and clinical activity in SLE.Methods A total of 275 patients with SLE completed this phase of a prospective observational study. At entry into the study, the BAFF gene expression levels were determined in peripheral blood RNA. Serum concentration of BAFF protein was also measured. We then determined clinical associations with SLE disease history, SLE activity on the same day and SLE activity over the course of the next year.Results Elevated BAFF gene expression was associated with a history of more leucopenia and serologically with more autoantibodies (anti-dsDNA, anti-Sm, anti-Ro, anti-La and anti-RNP) and low complement. Patients with higher amounts of BAFF transcript had higher measured levels of clinical disease activity. Initial high levels of BAFF gene expression also predicted increased disease activity over the course of the next year. In contrast, serum concentration of BAFF protein was not strongly associated with same-day global disease activity or with future disease activity.Conclusions BAFF gene expression level is associated with clinical and serological SLE activity on the same day and predictive of clinical activity over the next year. BAFF gene expression is a better measure and predictor of SLE disease activity than the serum BAFF protein level.