Effect of bortezomib treatment on plasma IgG and anti-dsDNA IgG in control and SLE mice. A, Anti-dsDNA IgG measured at 34 weeks of age in control and SLE mice. Plasma levels of anti-dsDNA IgG were higher in SLE mice and were lowered by bortezomib treatment. *, P<0.001 vs. control-vehicle and control-bortezomib; #, P<0.01 vs. SLE-bortezomib. B, Plasma IgG concentrations measured at 34 weeks of age in control and SLE mice. IgG concentrations were higher in SLE mice as compared to control mice, but were significantly lower after bortezomib treatment. *, P<0.05 vs. control-vehicle; #, P<0.01 vs. control-bortezomib and SLE-bortezomib.