5B-G). A significant increase in TGF-β expression (at 36 weeks) was observed. There Cobimetinib clinical trial was a trend toward an increase in IL-10

expression but this did not reach statistical significance. In addition, there was a transient decrease in TNF-α at week 24. This profile approximately mirrors the depletion and recovery of the B-cell compartment after rituximab treatment. Finally, we analyzed the expression of the cytotoxic T-cell granule proteins granzyme A and perforin but found no significant differences (Fig. 5H,I). Although this study was not designed to determine clinical efficacy, we analyzed the effects of rituximab on liver biochemistries (Fig. 6). The mean serum alkaline phosphatase was significantly decreased at 2, 24, and 36 weeks (294.7 ± 51.1, 206.7 ± 21.9, and 211.8 ± 25.4, respectively) compared with baseline (328.8 ± 50.0) (IU/L ± SEM). No significant changes were observed in the serum AST, ALT, γ-GTP,

or total bilirubin. There were no significant differences in pretreatment and week 52 PBC-40 scores. In this study, we examined the safety and immunologic effects of selective B-cell depletion using the anti-CD20 monoclonal antibody rituximab, in patients with PBC and an incomplete response to UDCA. During a 52-week follow-up period, we assessed liver enzyme levels, antibody levels, and lymphocyte populations, with special emphasis on T-cell and B-cell subsets. Our results suggest that rituximab is safe, transiently reverses several of the immunologic abnormalities characterized in PBC, and may have potential therapeutic effect in this difficult to treat PBC population. Although PBC is a relatively homogeneous disease in terms of R788 mw demographics (middle-aged women) and autoantibodies (AMAs), disease severity and response to UDCA is markedly heterogeneous. Several studies have documented that subgroups of patients with PBC without a biochemical about response to UDCA are at greater risk of disease progression, demonstrating that there is a need for new therapies.11, 29, 30 B-cell depletion has the potential to ameliorate autoimmune disease

by decreasing autoantibody production as well as by decreasing antigen presentation by B cells. Several studies, on subjects such as antineutrophil cytoplasmic antibody (ANCA)–associated vasculitis (AAV),31 IgM antibody–associated polyneuropathies,32 RA,33 and SLE,34 have reported that B-cell depletion with rituximab resulted in reduced levels of autoantibodies and alleviation of these autoimmune diseases in patients. In the current study, we observed declines in autoantibodies, suggesting that autoreactive plasma cells can be eradicated if their B-cell progenitors are eliminated. In our study, the titer of AMAs decreased significantly, especially IgA and IgM AMA, but only transiently, suggesting that repeated treatment would be required and also suggesting the possibility that complete removal of the progenitor cells could result in eradication of the AMA-secreting plasma cells.