The proportions of CD226+ B cells and CD226+ CD8+ T cells were significantly higher in SLE patients than in HCs (Figure 1A and Supplementary Figure 1A), whereas those of CD226+ CD4+ T cells and CD226+ NK cells were almost the same between the two groups (Supplementary Figures 1B, C). This evidence concerns the gene CD226 and systemic lupus erythematosus.