IDO1 and systemic lupus erythematosus: Subsequently, these results were validated by RT‐qPCR, confirming the up‐regulation of EPHA4 and LEFTY1 and the down‐regulation of CHCHD2, IDO1 and S100A10 in hiPSCs‐SLE compared to healthy hiPSCs; the expression of IGFBP5 and CCL26 remained unchanged (Figure 2C).