CD45w/w/Pep−/− double mutant mice develop lymphoproliferation and autoimmunity. Abbreviations apply to all subsequent figures : WEDGE = CD45w/w; PEP = Pep−/−; DNASE1 = Dnase1−/−; DOUBLE = CD45w/w/Pep−/− (A) ELISA for IgG autoantibodies reactive to double stranded DNA were performed on sera from CD45w/w/Pep−/− double mutant mice at the indicated time points. Values represent individual mice and were normalized to average MRL/lpr serum = 1000 arbitrary elisa units. Inset represents anti-nuclear antibody staining pattern for 1:100 dilution of representative CD45w/w/Pep−/− double mutant serum. (B) ELISA for IgG dsDNA autoantibodies of sera from various genotypes sampled at 9–10 months of age, normalized as in panel A. (C) Representative spleens and lymph nodes from genotypes at 5 months of age. (D) Lymph node absolute cell counts at 6 months of age. Values are the mean of three biological replicates +/− SEM. Similar results obtained at multiple time points ranging from 6 weeks to 12 months of age in at least 5 independent experiments each including 3 animals/genotype. (E) – (H) Hematoxylin and eosin staining of formalin fixed kidney sections from wild type and CD45w/w/Pep−/− double mutant animals at 12 months of age. Representative specimens at 10X (E, F) and 20X (G, H) magnification are depicted.