The statistical difference between groups was determined using a two-tailed Mann-Whitney nonparametric test with 95% confidence interval. All results are expressed as the mean ± SEM. The Prism statistical package (GraphPad Software Inc, La Jolla,

CA) was used. P < 0.05 was considered statistically significant. To assess the efficacy of the B cell depletion, the frequency of CD19+ cells in peripheral blood was quantified by flow cytometry. The vast majority AG-014699 supplier of B cells were depleted 1 week after the beginning of antibody administration in mice treated with either anti-CD20 (Fig. 1A-C) or anti-CD79 (Fig. 1B-D), whereas control mice exhibited no detectable changes in B cell frequency. Indeed, the frequency of CD19+ cells in peripheral blood mononuclear cells from anti-CD79–treated mice was 9.60% versus 46.89%

in controls (P < 0.001) after 1 week of treatment, and 0.34% in anti-CD20–treated mice versus 32.63% in control mice (P < 0.001). Importantly, both treated groups consistently displayed marked depletion of B cells after 8 weeks of therapy. B cell depletion was also assessed in the livers and spleens of the anti-CD20–treated and anti-CD79–treated mice (Table 1). Again, these mice demonstrated a decrease in B cells compared with control mice. The effect of B cell depletion on serum reactivity against PDC-E2 was assessed at weeks 4 and 8 after the first immunization with 2OA. Whereas mice treated with control antibodies produced high titers of PDC-E2–specific antibodies, sera from mice depleted of B cells showed undetectable levels of PDC-E2 reactive antibodies (P < 0.0001) (Fig. 2). Liver sections www.selleckchem.com/products/Lapatinib-Ditosylate.html from mice treated with anti-CD20 (Fig. 3A) and anti-CD79 (Fig. 4A) demonstrated a marked increase of cellular infiltrates in the portal tract and around the interlobular bile ducts, as well as an overall marked increase in liver inflammation compared with their respective controls (data not shown). Increased infiltration of

lymphocytes or mononuclear cells surrounding damaged bile ducts was frequently observed in portal areas. The degrees of portal tract inflammation plotted individually are shown in Figs. 3B and 4B. Furthermore, bile duct damage was observed, and 上海皓元医药股份有限公司 epithelioid granulomas were scattered within some portal tracts and also in hepatic parenchyma. Bile duct damage was studied by immunostaining with anti-CK22 (Fig. 5). Histological findings characteristic of PBC-like disease, including interlobular bile duct damage and nonsuppurative destructive cholangitis, were readily noted in the liver tissues from B cell–depleted mice. To clarify whether T cell infiltration was affected by B cell depletion with anti-CD20 and anti-CD79, total T cell numbers in the liver and spleen were quantified by way of flow cytometric analysis (Table 1). The number of CD3+ T cells, as well as absolute number of liver CD4+ and CD8+ T cells, was significantly increased in livers of B cell–depleted mice compared with control groups.