Jan Schulte am Esch

Portal application of autologous CD133+ bone marrow cells to the liver : a novel concept to support hepatic regeneration

The liver has a large capacity for regeneration after resection. However, below a critical level of future liver remnant volume (FLRV), partial hepatectomy is accompanied by a significant increase of postoperative liver failure. There is accumulating evidence for the contribution of bone marrow stem cells (BMSCs) to participate in liver regeneration. Here we report on three patients subjected to intraportal administration of autologous CD133+ BMSCs subsequent to portal venous embolization of right liver segments, used to expand left lateral hepatic segments as FLRV. Computerized tomography scan volumetry revealed 2.5‐fold increased mean proliferation rates of left lateral segments compared with a group of three consecutive patients treated without application of BMSCs. This early experience with portovenous application of CD133+ BMSCs could suggest that this novel therapeutic approach bears the potential of enhancing and accelerating hepatic regeneration in a clinical setting.

Portal Vein Embolization vs. Portal Vein Ligation for Induction of Hypertrophy of the Future Liver Remnant

The objective of this study was to assess the efficacy of right portal vein embolization (PVE) vs. right portal vein ligation (PVL) for induction of hypertrophy of the left lateral liver lobe before extended right hepatectomy. Thirty-four patients with primary or secondary liver tumors and estimated remnant functional liver parenchyma of less than 0.5% of body weight underwent either right PVE (transcutaneous, n= 10; transileocolic, n =7) or right PVL (n=17). Liver volume was assessed by CT scan before occlusion of the right portal vein and prior to resection. There were no deaths. The morbidity rate in each group was 5.8% (PVE, 1 abscess; PVL, 1 bile leak). The increase in liver volume was significantly higher after PVE compared with PVL (188±81 ml vs. 123±58 ml) (P= 0.012). Postoperative hospital stay was significantly shorter after PVE in comparison to PVL (4±2.9 days vs. 8.1±5.1 days;P<0.01). Curative liver resection was performed in 10 of 17 patients after PVE and 11 of 17 patients after PVL. PVE and PVL were found to be feasible and safe methods of increasing the remnant functional liver volume and achieving resectability for extended liver tumors. PVE results in a significantly more efficient increase in liver volume and a shorter hospital stay.

Ep-CAM expression in squamous cell carcinoma of the esophagus: a potential therapeutic target and prognostic marker

BackgroundTo evaluate the expression and test the clinical significance of the epithelial cellular adhesion molecule (Ep-CAM) in esophageal squamous cell carcinoma (SCC) to check the suitability of esophageal SCC patients for Ep-CAM directed targeted therapies.MethodsThe Ep-CAM expression was immunohistochemically investigated in 70 primary esophageal SCCs using the monoclonal antibody Ber-EP4. For the interpretation of the staining results, we used a standardized scoring system ranging from 0 to 3+. The survival analysis was calculated from 53 patients without distant metastasis, with R0 resection and at least 2 months of clinical follow-up.ResultsEp-CAM neo-expression was observed in 79% of the tumors with three expression levels, 1+ (26%), 2+ (11%) and 3+ (41%). Heterogeneous expression was observed at all expression levels. Interestingly, tumors with 3+ Ep-CAM expression conferred a significantly decreased median relapse-free survival period (log rank, p = 0.0001) and median overall survival (log rank, p = 0.0003). Multivariate survival analysis disclosed Ep-CAM 3+ expression as independent prognostic factor.ConclusionOur results suggest Ep-CAM as an attractive molecule for targeted therapy in esophageal SCC. Considering the discontenting results of the current adjuvant concepts for esophageal SCC patients, Ep-CAM might provide a promising target for an adjuvant immunotherapeutic intervention.

Technical Refinements and Results in Full-Right Full-Left Splitting of the Deceased Donor Liver

Objective:Splitting of the liver at the line of Cantlie of otherwise healthy people is accepted worldwide as a reasonable procedure for the donors in adult living donor liver transplantation. A similar operation is still considered as experimental if performed in the deceased donor liver. The aim of this study is to evaluate the technical evolution and the results of this variant splitting technique. Patients and Methods:From January 1999 to August 2004, a total of 35 transplants of hemilivers from deceased donors (segments V–VIII: n = 16 and segments (I)II–IV: n = 19) were performed in our center. Seven splits were performed in situ and 12 ex situ. Splitting of the vena cava was applied in 18 splits and splitting of the middle hepatic vein in 8. Seven adults and 12 adolescents received the left hemiliver with a mean age of 12 years (range, 3–64 years), of whom 21% were UNOS status 1. Recipients of right hemilivers were exclusively adults with a mean age of 48 years (range, 31–65 years), none of them were high urgent. The outcome of these 35 recipients of hemilivers was prospectively evaluated. Results:Mean deceased donor age was 27 years (range, 12–57 years), the donors body weight ranged between 55 kg and 100 kg. The mean weight of the right and left hemilivers was 1135 g (range, 745–1432 g) and 602 g (range, 289–1100 g), respectively. The mean graft recipient weight ratio in left and right hemiliver group was 1.46% (range, 0.88%–3.54%) and 1.58% (range, 1.15%–1.99%), respectively. Median follow-up was 27.4 months (range, 1–68.3 months). Four patients died (actual patient survival FR group: 87.5% versus FL group: 89.5%), 3 due to septic MOF and 1 due to graft versus host disease. In each of the 2 groups, 2 recipients had to undergo retransplantation, which resulted in an actual right and left hemiliver survival rate of 75% and 84%, respectively. The causes for retransplantation were primary nonfunction in 2 left hemilivers, chronic graft dysfunction in 1 right hemiliver, and recurrence of the primary disease in 1 recipient of a right hemiliver. Primary poor function was observed in 1 recipient of a right hemiliver. Early and late biliary complications occurred in both right and left hemiliver groups at the rate of 37.5% (n = 6) and 21% (n = 4), respectively. Arterial, portal, and venous complications were not observed in either group. Conclusion:The technical development of splitting along Cantlies line is almost complete with the last challenge being the reduction of biliary complications. The key to success is the choice of adequate deceased donors and recipients. Full-right full-left splitting is safely possible and should be considered as a reasonable instrument to alleviate mortality on the adult waiting list and to reduce the need for adult and adolescent living donation.

Infusion of CD133+ bone marrow-derived stem cells after selective portal vein embolization enhances functional hepatic reserves after extended right hepatectomy: a retrospective single-center study.

Objective:This study was designed to evaluate the clinical outcome of patients undergoing portal vein embolization (PVE) and autologous CD133+ bone marrow–derived stem cell (CD133+ BMSC) application before extended right hepatectomy. Background:We have previously shown that portal venous infusion of CD133+ BMSCs substantially increases hepatic proliferation, when compared with PVE alone. Methods:Among 40 consecutive patients with a median follow-up of 28 months (7.4–57.2) scheduled for extended right hepatectomy, we compared a preconditioned group with PVE and CD133+ BMSC cotreatment (PVE+SC group, n = 11) and a group pretreated only with PVE (PVE group, n = 11). Functional and overall outcomes after extended right hepatectomy were evaluated. Patients without presurgical treatment served as controls (n = 18). Results:In preconditioned patients, mean hepatic growth of segments II/III 14 days after PVE in the PVE+SC group was significantly higher (138.66 mL ± 66.29) when compared with that of PVE group patients (62.95 mL ± 40.03; P = 0.004). There were no significant differences among all 3 groups regarding general and oncological characteristics and functional parameters on postoperative day (POD) 7. Lack of hepatic preconditioning, extrahepatic extension of resection, and postoperative complications were of negative prognostic value, using univariate analysis (P < 0.05). In multivariate analysis, freedom from postoperative major complications (P = 0.012), coagulation status on POD 7 (international normalized ratio < 1.4; P = 0.027), and presurgical expansion of the future liver remnant volume (P = 0.048) were positively associated with overall survival. Post hoc analysis revealed a better survival for the PVE+SC group (P = 0.028) compared with the PVE group (P = 0.094) and compared with controls. conclusion:Promising data from this survival analysis suggest that PVE, together with CD133+ BMSC pretreatment, could positively impact overall outcomes after extended right hepatectomy.

Nonstructural 3/4A protease of hepatitis C virus activates epithelial growth factor–induced signal transduction by cleavage of the T‐cell protein tyrosine phosphatase

The hepatitis C virus (HCV) is a worldwide major cause of chronic liver disease with a high tendency to establish a persistent infection. To permit persistent replication of viral genomes through the cellular translation machinery without affecting host cell viability, viruses must have developed mechanisms to control cellular cascades required for sufficient viral replication, on the one hand, and to adapt viral replication to the cellular requirements on the other hand. The present study aimed to further elucidate mechanisms by which HCV targets growth factor signaling of the host cell and their implications for viral replication. The study describes a novel mechanism by which HCV influences the activation of the epithelial growth factor receptor/Akt pathway through a nonstructural (NS)3/4A‐dependent down‐regulation of the ubiquitously expressed tyrosine phosphatase T cell protein tyrosine phosphatase (TC‐PTP). NS3/4A is demonstrated to cleave TC‐PTP protease‐dependently in vitro at two cleavage sites. The in vivo relevance of this finding is supported by the fact that down‐regulation of TC‐PTP protein expression could also be demonstrated in HCV‐infected individuals and in transgenic mice with intrahepatic expression of NS3/4A. Conclusion: This down‐regulation of TC‐PTP results in an enhancement of epithelial growth factor (EGF)‐induced signal transduction and increases basal activity of Akt, which is demonstrated to be essential for the maintenance of sufficient viral replication. Hence, therapeutic targeting of NS3/4A may not only disturb viral replication by blocking the processing of the viral polyprotein but also exerts unforeseen indirect antiviral effects, further diminishing viral replication. (HEPATOLOGY 2009;49:1810–1820.)

O‐Linked glycosylation and functional incompatibility of porcine von Willebrand factor for human platelet GPIb receptors

Abstract:  Background:  Xenograft rejection is associated with vascular inflammation, thrombocytopenia and the accelerated consumption of coagulation factors. Primary biological incompatibilities of the xenograft in the regulation of clotting appear to amplify pathological processes associated with rejection. The functional incompatibility of porcine von Willebrand factor (vWF) expressed within the xenograft vasculature may heighten interactions with the primate platelet receptor GPIb, hence augmenting formation of platelet microthrombi and vascular injury. Here, we address the functional impact of O‐linked glycosylation of the vWF A1 domain on primate platelet activation.

Down-Regulation of CDH1 Is Associated with Expression of SNAI1 in Colorectal Adenomas

Introduction Down-regulation of E-cadherin (CDH1) and epithelial-mesenchymal transition (EMT) are considered critical events for invasion and metastasis of colorectal carcinoma. Here we tested whether the important regulators of E-cadherin expression SNAI1 and TWIST1 are already detectable in human colorectal adenomas. Methods RNA was extracted from a set of randomly selected formalin-fixed and paraffin-embedded (FFPE) colorectal adenomas (n = 41) and normal colon mucosa (n = 10). Subsequently mRNA expression of CDH1, CDH2, SNAI1 and TWIST1 was analysed by quantitative RT-PCR analysis. CDH1 as well as SNAI1 protein expression were assessed by immunohistochemistry (IHC). Results SNAI1 mRNA was expressed in 78% (n = 32/41), TWIST1 mRNA in 41% (n = 17/41) and CDH2 mRNA in 41% (n = 17/41) of the colorectal adenoma tissue, while normal colon mucosa was negative for these transcription factors. We found a significant correlation between reduced CDH1 and the presence of SNAI1 mRNA expression and for combined SNAI1 and TWIST1 mRNA expression, respectively. A correlation between CDH2 mRNA expression and reduced CDH1 expression was not observed. We confirmed the relationship between SNAI1 expression and reduced E-cadherin expression on the protein level via IHC. Conclusion Our data show that SNAI1 and Twist1 are already expressed in benign precursor lesions of colorectal cancer and that SNAI1 expression was significantly correlated with lower expression of CDH1. Whether these findings reflect true EMT and/or are a sign of a more aggressive biology need to be investigated in further studies.

Platelet activation and increased tissue factor expression on monocytes in reperfusion injury following orthotopic liver transplantation

Platelets have been implicated in the pathogenesis of liver damage after orthotopic liver transplantation (OLT). Early graft dysfunction is frequently caused by reperfusion injury subsequent to cold ischemia (IRI). Therefore, we investigated activation of the pivotal haemostatic cells, platelets and monocytes, from patients with elevated markers of IRI and from patients with uneventful course (control-group), respectively during the first week after OLT. Flow cytometry analysis of citrate anticoagulated blood samples revealed that platelets from IRI patients became significantly activated within 48 h after OLT in vivo, with increased surface presentation of P-selectin, CD40L, thrombospondin-1 and tissue-factor. Platelet activation in IRI patients on post-transplant day 2 was accompanied by significantly enhanced tissue-factor expression on peripheral blood monocytes, significant elevated levels of C-reactive protein and hepatocellular damage. Towards post-transplant day 4, levels of platelet-derived microparticles rose significantly in IRI patients if contrasted to control patients. Thus, activated cellular haemostasis is involved in the early inflammatory response of hepatocellular damage subsequent to reperfusion of the transplanted liver. Targeting distinct activation patterns of platelets and monocytes in an early phase of hepatic grafting may counteract the extent of IRI via inhibition of micro-thrombus formation and inflammation without exacerbating the existing bleeding risk.

Coagulation, platelet activation and thrombosis in xenotransplantation.

Purpose of reviewXenotransplantation may become clinically feasible once the mechanisms of graft loss and rejection are better understood. Inflammatory reactions to vasculature of grafted pig organs and pancreatic islets have been linked to procoagulant activation and consumption with resulting thrombosis that precludes long-term function. Although development of α-1,3-galactosyltransferase gene-knockout swine with removal of a dominant xenoantigen has been an important advance, major problems still persist. Recent findingsConsumptive coagulopathy and platelet sequestration are initiated by immune responses associated with xenograft rejection and are exacerbated by putative intrinsic functional incompatibilities. Thrombotic processes together with progressive xenograft microangiopathy and infarction are intertwined with humoral immune reactions that may be secondary, at least in part, to ‘natural’ or elicited nongalactosyl antibodies. These immune responses are further exacerbated by the documented intrinsic molecular incompatibilities in the vascular regulation of blood clotting and extracellular nucleotide homeostasis between discordant species. Hence, limited benefits have been achieved with currently available pharmacological antithrombotics and anticoagulants. SummaryProposed strategies to tackle this problem will include optimal immunosuppressive interventions, attempts to induce tolerance, judicious and more effective use of anti-thrombotics with development of mutant swine either transgenic for human anticoagulants and thromboregulatory factors or null for defined porcine procoagulants.