RNPC3 and lupus nephritis: General disease features of lupus nephritis in FcγRIIB-/-yaa mice were evaluated by renal microscopy (Fig 1, Fig 2A), presence of serum anti-dsDNA and anti-RNP antibodies (Fig 2B and 2C), proteinuria (Fig 2D) and renal expression levels of pro-inflammatory cytokines (Fig 2E).