Furthermore, we found that estradiol increases pro-inflammatory cytokines and chemokines (IL-8, IL-18, IL-23, CXCL1-7, MIP1α, and MIP1β), and level of estradiol positively-correlated with expression of pro-inflammatory cytokines and chemokines in SLE patients and with the levels of serum/plasma IL-6, IL-18, and IL-21/23 in SLE patients (Figures 2B, 3B, 4, 5, and 6). The gene discussed is IL21; the disease is systemic lupus erythematosus.