Rituximab induction to prevent the recurrence of PSC after liver transplantation—the lessons learned from ABO-incompatible living donor liver transplantation

Background. Multiple studies have failed to reveal an effective method for preventing the recurrence of primary sclerosing cholangitis (PSC) after liver transplantation (LTx). A national study conducted in Japan revealed several risk factors for the recurrence after living donor LTx (LDLTx); however, recipients of ABO-blood type incompatible (ABO-I) LTx were excluded from the previous analysis. In the present study, we investigated the efficacy of an immunosuppressive protocol in ABO-I LTx on the recurrence of PSC after LDLTx. Methods. We conducted a national survey and analyzed the outcome of recipients who underwent ABO-I LDLTx for PSC (n = 12) between 1994 and 2010 in 9 centers and compared the outcome with that of ABO-compatible LDLTx for PSC (n = 96). The key elements of the immunosuppressive regimen in ABO-I LTx are plasma exchange sessions to remove existing antibodies, and the use of immunosuppression to control humoral immunity. Rituximab was added to the immunosuppression regimen from 2006 onward; 5 patients received rituximab perioperatively. Results. All 7 recipients who underwent ABO-I LDLTx before 2006 (who did not receive rituximab) died of infection (n = 3), antibody-mediated rejection (n = 1), ABO-incompatibility associated cholangiopathy (n = 1) or recurrence of PSC (n = 2). In contrast, we found that all 5 recipients from 2006 (who were treated with rituximab) retained an excellent graft function for more than 7 years without any recurrence of PSC. Conclusions. The findings of this study shed light on the efficacy of a novel strategy to prevent the recurrence of PSC and the possible mechanisms provided by rituximab treatment are discussed.