SDC1 and systemic lupus erythematosus: Iberdomide added to SLE B cells on day 4 did not impact the percentage of CD27+IgD- B cells, CD27+CD38+ plasmablasts, CD20lowCD27+CD38+CD138+ plasma cells and naïve B cells (figure 3B, C) nor the expression of CD27 on B cells (figure 3D).