The proportions of three NK cell subsets in CD45+ lymphocytes from SLE patients were decreased (CD56dimCD57+ NK cell percentage: 9.01 ± 6.56% and 3.32 ± 3.73% for HCs and SLE respectively; CD56bright NK cell percentage: 0.49 ± 0.21% and 0.39 ± 0.39% for HCs and SLE respectively; CD56dimCD57− NK cell percentage: 7.60 ± 4.04% and 4.15 ± 3.38% for HCs and SLE respectively), and the two groups of CD56dim NK cells reached the statistically significant differences (P < 0.01) (Fig. 2C, right panel). Here, PTPRC is linked to systemic lupus erythematosus.