IL-15 enhanced CD1d expression of α-GalCer treated iNKT cells from SLE patients (78.0±2.5% vs. 72.6±2.8%, p = 0.014) but not controls (68.3±5.2% vs. 65.5±6.0%, p = 0.374) (Fig 5B). Here, CD1D is linked to systemic lupus erythematosus.