The percentages of granzyme B+ CD56bright NK cells were higher in SLE patients with active disease compared to those in controls (75.7 ± 5.9% vs. 53.1 ± 4.7%, p = 0.002) and to SLE patients with inactive disease (75.7 ± 5.9% vs. 59.3 ± 6.2%, p = 0.024), respectively. Here, GZMB is linked to systemic lupus erythematosus.