TNFSF13B and systemic lupus erythematosus: TACI-Ig has previously been investigated in the autoimmune literature for treatment of systemic lupus erythematosus (SLE) rheumatoid arthritis.[12, 36] In an SLE trial, APRIL BLyS blockade via atacicept (TACI-Ig) demonstrated a significant reduction in serum IgG levels which supports the idea that APRIL/BLyS blockade via TACI-Ig is able to successfully target plasma cells.[37] Gross et al. utilized TACI-Ig in a murine model of collagen-induced arthritis with treatment given three times weekly for three weeks either before or during the onset of disease.