A T cell gene expression panel for the diagnosis and monitoring of disease activity in patients with systemic lupus erythematosus

•A 40 T cell gene expression panel accurately differentiates SLE samples from control.•This panel's accuracy improved when the top 3 genes were used (OAS2, CD70 and IL10).•Combined expression levels of these genes correlate with markers of disease activity.•The three gene panel may also be applied to peripheral blood mononuclear cell populations.

Systemic Lupus Erythematosus (SLE) remains a challenging disease to diagnose and follow, as no reliable biomarkers are known to date. We designed a gene expression panel with 40 genes known to play a role in SLE pathogenesis. We found that the combined expression of these genes in SLE T cells can accurately differentiate SLE from healthy individuals and patients with other autoimmune diseases. The accuracy of the test increased further (83%) when only three out of the initial genes (OAS2, CD70 and IL10) were used. A T cell score, calculated from the combined expression levels of these genes, correlated positively with various SLE activity markers in a cross-sectional cohort and in a few patients that were followed prospectively. These data showcase the usefulness of measuring mRNA levels of key molecules in diagnosing and following patients with SLE.