Fig. 6

Quantitative PCR analysis shows dose-dependent IGJ down-regulation by daratumumab ex vivo. a Positive correlation between IGJ mRNA and plasma cell count at baseline of isotype control. b Positive correlation between IGJ mRNA and plasma cell count at different daratumumab concentrations ex vivo. c-e IGJ expression at different daratumumab concentration at 72 h post-treatment in healthy controls (c, n = 7) and patients with systemic lupus erythematosus (SLE) (d, n = 4) and rheumatoid arthritis (RA) (e, n = 4). Relative expression of IGJ in the isotype control was normalized to 1 (shown as dashed line). f Positive correlation between normalized IGJ mRNA fold change and plasma cell count fold change compared to isotype control at various daratumumab concentrations. g Correlation between the number of plasma cells at baseline and the maximal IGJ mRNA down-regulation. Data shown in a, b, f and g represent two donors with SLE and sixhealthy control donors