Herein, leukocyte uPAR expression and plasma suPAR levels were explored in unstimulated and cytokine-treated (tumor necrosis factor; TNF or interferon-α; IFN-α) blood from patients with SLE (n = 37) and healthy blood donors (HBD; n = 27). The gene discussed is PLAUR; the disease is systemic lupus erythematosus.