CD161- iNKT subsets, in contrast to CD161+ iNKT subsets, did not respond to α-GalCer stimulation alone in controls (6.0±1.6% vs 4.7±1.2%, p = 0.059) and SLE patients(2.7±0.5% vs 2.3±0.4%, p = 0.158) (Fig 3B) Similar to that observed with CD161+ iNKT subsets, addition of IL-15 to α-GalCer cultures resulted in greater expansion of CD161- iNKT subsets compared to α-GalCer alone in controls(11.4±1.5% vs 5.9±1.6%, p = 0.002) and SLE patients (5.7±1.0% vs 2.7±0.5%, p = 0.002). Here, IL15 is linked to systemic lupus erythematosus.