Based on the above reported data showing a significant negative correlation between ERβ expression and SLEDAI-2K score on the one hand and a significant positive correlation between anti-ERα Ab serum levels and SLEDAI-2K score on the other hand, we compared in T cells from SLE patients with SLEDAI-2K scores <6 and ≥6 the impact of these antibodies and/or E2 on ER-dependent signaling pathways. This evidence concerns the gene ESR1 and systemic lupus erythematosus.