To evaluate whether the differential expression of ERβ in SLE T cells from patients with SLEDAI-2K scores ≥6 and those with SLEDAI-2K scores <6 could affect T cell response to the ERβ-selective agonist DPN, purified T cells from SLE patients were treated with this compound and analyzed for the expression of activation markers, i.e., CD25, HLA-DR, and CD95 molecules, and the production of a panel of cytokines, i.e., IFN-γ, IL-4, and IL-17. The gene discussed is FAS; the disease is systemic lupus erythematosus.