Serum levels of APRIL, BAFF, and IL-10 in systemic lupus erythematosus have limited utility as biomarkers for disease activity or flare prediction

In our study, higher BAFF levels were associated with longer disease duration, while elevated IL-10 levels correlated with the SLEDAI score. Such correlations were not observed considering APRIL. However, all cytokines were also linked to higher anti-dsDNA antibody titers. Nevertheless, no significant differences in serum levels of APRIL, BAFF, and IL-10 were observed between active and inactive SLE patients, but also controls, limiting their potential as biomarkers of disease activity, but also their ability to predict disease flares. Key Points • Serum APRIL, BAFF, and IL-10 levels were similar between active and inactive SLE patients or compared with healthy controls. • BAFF correlated positively with disease duration, and IL-10 with the SLEDAI score. • None of the cytokines predicted future disease flares during a median follow-up period of 5.5 years.