Among patients who received non-biological ST alone, patients who developed severe flares showed an increase while patients who did not develop severe flares showed a decrease from baseline through week 24 in CD19+CD20+CD27+ memory B cells (+14.3% versus -7.7%; P=0.023), CD19+CD20-CD138+ long-lived plasma cells (+6.7% versus -27.2%; P=0.002) and CD19+CD27brightCD38bright SLE-associated plasma cells (+41.2% versus -6.1%; P=0.038), resulting in a significant difference in all cases. Here, SDC1 is linked to systemic lupus erythematosus.