IL-15 was superior to α-GalCer alone in increasing the percentages of CD161+ iNKT cells in controls (13.3±3.5% vs 5.2±1.0% p = 0.011) and SLE patients (5.0±1.0% vs 1.8±0.3%, p = 0.001). The gene discussed is KLRB1; the disease is systemic lupus erythematosus.