CD56dim NK cells from active SLE patients expressed lower percentages of TNF-α compared to those from controls (46.9 ± 6.6% vs. 73.7 ± 2.5%, p = 0.001), while the percentages of TNF-α expressing CD56bright NK cells did not differ (73.7 ± 7.6% vs. 73.0 ± 2.7%, p = 0.812). The gene discussed is TNF; the disease is systemic lupus erythematosus.