Anti-CD20-mediated depletion of B cells attenuates hepatic fibrosis and autoantibodies in Mdr2−/− mice. (A) Mdr2−/− mice were administered either anti-mouse CD20 (clone 18B12, IgG2a, Biogen) mAb or isotype control (2B8, IgG2a) as 250μg in sterile PBS i.p. every 7 days starting at 8 weeks continued until 25 weeks of age as demonstrated. (B) Blind quantification of liver fibrosis following antibody treatment is shown. (C) Histologic analysis of representative liver specimens for H&E and Sirius red staining (mag. 100×) are shown. (D) Frequencies of intrahepatic myeloid populations monocytes (CD11b+Ly6c++) and neutrophils (CD11b+Gr1+) are shown. (E-G) Serum specimens collected from animals were analyzed for IgG (E), ANA titers (F) and C1q titers (G) as described in Materials and Methods section. Statistical significance was determined by one-way analysis of variance (ANOVA) with Bonferroni’s multiple comparison test. **P<.001, ***P<.0001. Error bars reflect SEM.