TRIM21 and Splenomegaly: Compared with WT B6.lpr (Trim21+/+ B6.lpr) mice, Trim21−/− B6.lpr mice showed more severe splenomegaly (Fig. 4a, b), lymph node enlargement (Supplementary Fig. 3a) and renal inflammation as well as albuminuria (Fig. 4c–e).