TRAF3 transgenic mice develop systemic inflammation. (A) Histologic analysis. H&E staining shows lymphoid neogenesis (tertiary lymphoid organ [TLO] formation) in omentum and pancreatic parenchyma partly replaced by inflamed adipose tissue in TRAF3 mouse. (B) B cells in TLO were stained with B220 mAb. (C) T cells in TLO were stained with anti-CD3 monoclonal antibody (mAb). (D) H&E staining of an inflammatory cuff surrounding renal artery with thickened tunica media. (E) H&E staining of a joint from a representative TRAF3 mouse with arthritis. Note the distended joint spaces, pannus formation, proliferation of synoviocytes, the irregular proliferation of cartilage at the junction of cartilage bone, and synovium or cartilage erosion. Bars in panels A through E represent 100 μm. (F) Analysis of proinflammatory proteins in serum. Sera from TRAF3 transgenic mice and wild-type littermates (10-15 months old) were analyzed to determine the concentrations of inflammatory cytokines and CRP. Statistical significance was determined by unpaired Student t test. P values are indicated in figure. Hash marks indicate means.