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Background: The development of liver graft disease is partially determined by individual genetic background. Interleukin 28B (IL28B) is strongly suspected to be involved in susceptibility for hepatitis C virus (HCV) infection, inflammation, and antiviral treatment response before and after liver transplantation (LT). Currently, the role of IL28B polymorphism (rs12979860) in the development of hepatocellular carcinoma (HCC) is unclear, and only limited data are available on the course of HCV recurrence., Methods: One hundred sixty-seven HCV-positive patients after LT were genotyped for IL28B (C→T; rs12979860). Sixty-one patients with histologically confirmed HCC in the explanted liver were compared with 106 patients without HCC regarding IL28B genotypes. Among patients with HCC, IL28B genotypes were correlated with tumor histology and pretransplant α-fetoprotein (AFP) levels. Furthermore, the role of IL28B polymorphism was evaluated regarding interferon-based treatment success and fibrosis progression after LT., Results: The prevalence of HCC in explanted livers was significantly higher among patients with TT genotype, suggesting a protective role of the C allele in HCC development (P=0.041). Median AFP level was closely to significance higher in the presence of T allele (P=0.052). Significant differences in IL28B genotype distribution were detected between AFP-negative and AFP-positive HCCs (<15 μg/L vs. >15 μg/L; P=0.008). Although no impact could be observed regarding acute cellular rejection (P=0.940), T allele was significantly associated with antiviral therapy failure (P=0.028) and faster development of advanced fibrosis (P=0.017) after LT., Conclusion: IL28B polymorphism seems to be involved in the development of HCV-induced HCC and in the course of HCV recurrence after LT. T allele may be regarded as a genetic risk factor for HCV-related carcinogenesis, posttransplant fibrosis progression, and antiviral therapy failure.

Background: Recurrent hepatitis C virus (HCV) after liver transplantation (OLT) is a major cause of graft loss in HCV-positive patients. In this study, we evaluated the efficacy and safety of pegylated interferon alfa-2b (peginterferon) and ribavirin treatment for recurrent HCV after OLT and analyzed the influence of antiviral treatment on the histological course of recurrent hepatitis., Methods: Twenty-five patients with recurrent HCV (genotype 1 n=20 and 2-4 n=5) received peginterferon (1 mg/kg/weekly) and ribavirin (600 mg) for 48 weeks. Viral load prior to treatment was below 1,000,000 (IU/ml) in 11 of 25 patients. Sustained antiviral response was defined as undetectable HCV-RNA in serum 6 months after stopping of therapy. All patients underwent liver biopsy prior to treatment and after 72 weeks., Results: Seventeen of 25 patients became HCV-RNA-negative after treatment (68%). Sustained virologic response (SVR) was achieved in 9/25 (36%) patients. Liver specimen showed increase of fibrosis from 1.7 to 2.0 within 72 weeks. Side effects like neutropenia (60%) and anemia (36%) were treated with G-CSF, erythropoietin, and dose reduction of peginterferon and ribavirin., Conclusions: The use of peginterferon is safe and effective in patients with recurrent HCV. Treatment of side effects, especially neutropenia or anemia, helped to maintain antiviral therapy. Despite a viral response of 68% during treatment, the patients showed further progress of recurrent hepatitis in liver specimen.

Mesenchymal stem cells (MSCs) are capable of down-regulating alloimmune responses and promoting the engraftment of hematopoietic stem cells. MSCs may therefore be suitable for improving donor-specific tolerance induction in solid-organ transplantation. Cells from cadaveric vertebral bone marrow (V-BM), aspirated iliac crest-BM, and peripheral blood progenitor cells were compared. Cells were characterized by flow cytometry and colony assays. MSCs generated from V-BM were assayed for differentiation capacity and immunomodulatory function. A median 5.7 x 10(8) nucleated cells (NCs) were recovered per vertebral body. The mesenchymal progenitor, colony-forming unit-fibroblast, frequency in V-BM (11.6/10(5) NC, range: 6.0-20.0) was considerably higher than in iliac crest-BM (1.4/10(5) NC, range: 0.4-2.6) and peripheral blood progenitor cells (not detectable). MSC generated from V-BM had the typical MSC phenotype (CD105(pos)CD73(pos)CD45(neg)CD34(neg)), displayed multilineage differentiation potential, and suppressed alloreactivity in mixed lymphocyte reactions. V-BM may be an excellent source for MSC cotransplantation approaches.

Background: Although antibody mechanisms play a pathogenetic role in liver allograft rejection, no data exist on B lymphocytes, plasma cells, complement, and chemokines in rejected liver tissue., Methods: Liver biopsy specimens from 25 patients with acute allograft rejection (AR) (rejection activity index, RAI score: 1-9) were analyzed by immunohistochemistry (IH) and reverse transcriptase-polymerase chain reaction (RT-PCR) and compared with biopsy specimens taken prior to implantation (PI). The number of CD20 and CD138 cells was evaluated, and the presence and abundance of the chemokines macrophage inflammatory protein (MIP)-3alpha, CXCL9, CXCL10, CXCL11, CXCL12, and their receptors CCR-6, CXCR3, and CXCR4 were examined. Complement depositions were visualized by C4d IH., Results: The numbers of B lymphocytes (P=0.002) and plasma cells (P=0.022) were significantly higher in AR biopsy specimens compared with PI biopsy specimens. MIP-3alpha and CCR-6 cells were detected in the portal fields of all AR biopsy specimens. IH double staining revealed a colocalization of MIP-3alpha/CD20 cells; C4d deposits could be demonstrated along the portal capillaries. All examined chemokines and receptors could be detected in normal liver tissue and in AR biopsy specimens by RT-PCR and semiquantitative RT-PCR, demonstrating an overexpression of CXCL10 and -11., Conclusions: The significant increase of B lymphocytes and plasma cells during acute rejection, together with the lack of a significant increase of proliferating cells, indicates that the migration of B lymphocytes and plasma cells-promoted by the expression of B-cell activating chemokines/receptors-plays a key role in acute liver rejection. The C4d deposits along the portal capillaries indicate a humorally mediated alloresponse caused by the accumulated B and plasma cells.

Background: Tacrolimus in combination with prednisolone has been proven to be a safe and effective immunosuppressive induction therapy in solid organ transplantation. However, it remains unclear whether a tacrolimus-based quadruple induction regimen with azathioprine and an antilymphocytic preparation could further improve the results after orthotopic liver transplantation. Therefore, we designed a prospective, randomized study to compare the immunosuppressive efficacy of dual (tacrolimus and prednisolone) and quadruple (tacrolimus, azathioprine, ALG Merieux and prednisolone) induction after liver transplantation., Methods: After randomization, 120 consecutive patients of primary liver transplants were divided into the dual group (n=59) and the quadruple group (n=61) and followed for a minimum of 3 years., Results: Patient survival at 3 years was 88.2% in the dual versus 94.9% in the quadruple group. Overall 25 patients in each group (41 and 42%, respectively) developed acute rejection. There was no difference in the number and severity of rejections. In each group only four patients required OKT3-therapy, however, although three of four patients in the quadruple group responded to OKT3 and cleared rejection, none of the four patients in the dual group were treated successfully with OKT3 (P<0.02). Rejection in these patients resolved only after additional treatment with mycophenolate mofetil. Adverse events and infections were equally distributed in both groups. Asymptomatic Cytomegalovirus infections were more common in the quadruple group (P<0.02). As of today, only one patient developed posttransplant lymphoproliferative disease (dual group)., Conclusions: The data from our single-center study indicate that both tacrolimus-based dual and quadruple immunosuppressive induction regimens yield similar safety and effectiveness after liver transplantation.