Martin Wolff

Monokines inhibiting erythropoietin production in human hepatoma cultures and in isolated perfused rat kidneys

The blood level of erythropoietin (Epo) is often anomalously low in anemic patients with inflammatory or malignant diseases. Therefore, we studied effects of pure recombinant immunomodulatory peptides on Epo formation in cultures of the human hepatoma cell line, HepG2. Interleukin (IL)-1 beta, IL-1 alpha, and tumor necrosis factor alpha lowered Epo production with half-maximal inhibition at 2, 5, and 20 U/ml, respectively. IL-6, transforming growth factor beta 2 and interferon gamma did not inhibit. Furthermore, IL-1 beta (10 U/ml) proved to block Epo formation in isolated serum-free perfused rat kidneys. Proposedly, monokines play a role in the pathogenesis of Epo deficiency in various diseases.

Carcinoma of the ampulla of Vater: Comparative histologic/immunohistochemical classification and follow-up

A broad histomorphologic spectrum of ampullary carcinomas of Vater make a reproducible histologic classification difficult. Using cytokeratin immunohistochemistry, we present a new classification of ampullary carcinomas and analyze their clinical significance. Fifty-five invasive carcinomas of Vater’s ampulla were histologically classified into pancreaticobiliary, intestinal, and other types. Serial sections of all carcinoma specimens were additionally stained with antibodies to cytokeratins (CK7, CK20), apomucins (MUC1, MUC2, MUC5AC), CEA, CA19-9, Ki67, and p53. Follow-up of patients from 4 months to 22 years after surgery (mean interval, 51.6 months) was evaluated. Most carcinomas of the ampulla of Vater were of immunohistochemically pancreaticobiliary type (iPT, CK7+, CK20−; 54.5%) or intestinal type (immunohistochemically intestinal type [iIT], CK7−, CK20+; 23.6%). Some carcinomas of immunohistochemically “other” type (iOT both CK7+ and CK20+ or CK7− and CK20−; 21.8%) had precursor lesions of iIT or iPT. Carcinomas positive for MUC2 or CEA were associated with iIT (MUC2, P < 0.001; CEA, P = 0.003), whereas MUC5AC-positive carcinomas were related to iPT (P = 0.005). Our classification based on cytokeratin-immunohistochemistry correlated well with the histologic classification according to published criteria (κ-coefficient = 0.398; P < 0.001). Furthermore, histologically unusual types could be histogenetically related to pancreaticobiliary duct mucosa or intestinal mucosa. Therefore, all 4 signet-ring cell carcinomas were iIT carcinomas. Thus, cytokeratin immunohistochemistry allows a reproducible, histogenetically based categorization of ampullary carcinomas. However, neither histopathologic nor immunohistochemical subgroups significantly correlated with clinical outcome in our German collective. The overall survival was significantly shorter in males (P = 0.032) and patients with positive nodal stage (N1 < N0; P = 0.0025).

Early up-regulation of chemokine expression in fulminant hepatic failure

CC‐chemokines recruit and activate macrophages and T lymphocytes, the major components of inflammatory infiltrates in fulminant hepatic failure (FHF). To analyse the role of CC‐chemokines in the pathogenesis of FHF, this study examined serum levels and intrahepatic expression of MCP‐1, MIP‐1α, MIP‐1β, and RANTES in the livers and sera of patients with FHF and controls by ELISA, immunohistochemistry, and competitive RT‐PCR. Serum levels and intrahepatic expression of all chemokines studied in FHF exceeded the levels in chronic liver diseases and normal controls. Distinct patterns of expression of each chemokine were noted on Kupffer cells, sinusoidal endothelial cells, hepatocytes, lymphocytes, and bile ducts. Intrahepatic chemokine expression correlated closely with the extent of infiltration by macrophages and T lymphocytes (r = 0.65–0.95, p < 0.001). The functional relationship between intrahepatic chemokine release and infiltration was confirmed in chemotaxis assays by inhibiting chemotaxis induced by homogenates of liver tissue obtained from FHF patients with neutralizing MCP‐1, MIP‐1α, MIP‐1β, and RANTES antibodies. The time course of CC‐chemokine release was studied in the concanavalin A and the galactosamine/LPS mouse models of FHF. In both models, intrahepatic chemokine up‐regulation occurred as an early event prior to hepatic infiltration and liver damage. The data indicate that an abundant intrahepatic release of CC‐chemokines is an early and pivotal step in the pathogenesis of FHF. Copyright

Management of Drug-to-Drug Interactions Between Cyclosporine A and the Protease-Inhibitor Lopinavir/ Ritonavir in Liver-Transplanted HIV-Infected Patients

Highly active antiretroviral therapy (HAART) has improved the life expectancy of HIV‐infected patients, allowing orthotopic liver transplantation as a reasonable treatment option for selected patients with terminal liver disease. Both non‐nucleoside reverse transcriptase inhibitors and protease inhibitors, key elements of HAART, give rise to substantial drug‐to‐drug interactions with immunosuppressive drugs such as tacrolimus and cyclosporine A. After studying 12‐hour pharmacokinetic profiles in 3 HIV‐positive patients after liver transplantation, we describe how dosing of cyclosporine A can be adjusted to maintain effective immunosuppressive drug levels on a daily dosing schedule when ritonavir‐boosted indinavir or lopinavir‐based antiretroviral therapy is given. To avoid toxic drug levels, we used an orally available cyclosporine A formulation prepared from the commercial available intravenous solution, which enabled dose adjustments in 1‐mg increments. Under ritonavir‐boosted HAART, cyclosporine A levels showed markedly altered absorption/elimination characteristics with more or less constant blood‐levels throughout the dosing interval and prolonged elimination half‐lives up to 38 hours. To obtain equivalent areas under the curve of cyclosporine A, daily doses were reduced to 5–20% of the individual standard doses given before initiation of ritonavir‐boosted HAART. Because of the flat absorption/elimination profiles under ritonavir‐boosted HAART cyclosporine A, dosing could be reliably monitored long term by measuring cyclosporine A trough‐levels. (Liver Transpl 2004;10:939–944.)

Modulation of the Production of Erythropoietin by Cytokines: In vitro Studies and Their Clinical Implications1

The etiology of the anemia of chronic disorders is complex. Factors which clearly contribute to the suppression of erythropoiesis are (a) reduced iron availability and (b) stimulation of the synthesis of immunomodulatory peptides such as IL-1, TNF-alpha and IFN-gamma, which inhibit the proliferation of erythrocytic progenitors in the bone marrow. The question as to whether lack of EPO is of general importance in the pathogenesis of the anemia of chronic inflammatory and malignant diseases is still a subject of controversy. The present in vitro studies show that IL-1 and TNF-alpha, but not IFN-gamma significantly lower the pO2-dependent formation of EPO in HepG2 cultures. In addition, clinical examples are given of anomalously low or high EPO levels in association with diseases involving the immune system. It is proposed that monokines and related immunomodulatory peptides could play a role in the control of the production of EPO.

Current state of portosystemic shunt surgery

BackgroundA switch to decompressive shunt procedures is mandatory if endoscopic therapy fails to control recurrent variceal hemorrhage. Surgical shunt procedures continue to be safe, highly effective, and durable procedures to treat variceal bleeding in patients with low operative risk and good liver function.DiscussionIn cirrhotics, elective operations using portal flow preserving techniques such as a selective distal splenorenal shunt (Warren) and a partial portocaval small diameter interposition shunt (Sarfeh) should be preferred. Rarely, end-to-side portocaval shunt may serve as a salvage procedure if emergency endoscopic treatment or transjugular intrahepatic portosystemic shunt insertion fails to stop bleeding. Until definitive results from randomized trials are available patients with good prognosis (Child-Pugh A and B) should be regarded as candidates for surgical shunts. For patients with noncirrhotic portal hypertension, in particular with extrahepatic portal vein thrombosis, portosystemic shunt surgery represents the only effective therapy which leads to freedom of recurrent bleeding and repeated endoscopies for many years, and improves hypersplenism without deteriorating liver function or encephalopathy. Gastroesophageal devascularization and other direct variceal ablative procedures should be restricted to treat endoscopic therapy failures without shuntable portal tributaries.

Orthotopic liver transplantation in human immunodeficiency virus (HIV)‐positive patients: Outcome of 7 patients from the Bonn cohort

The outcome and clinical features of 7 HIV‐positive patients who were liver transplanted at Bonn University in the era of highly active antiretroviral therapy (HAART) between 1997 and 2004, analyzed by retrospective chart review, are reported. Reasons for orthotopic liver transplantation (OLT) were end‐stage liver disease due to chronic hepatitis C (n = 4) or hepatitis B (n = 1) or acute liver failure due to fulminant hepatitis B (n = 2). Immunosuppression was based on cyclosporine A and prednisone. HAART was reinitiated 1 month after transplantation, and immunosuppression was carefully adapted to account for drug‐drug interactions between cyclosporine A and protease inihibitors. Prednisone was withdrawn 5 months (median) after OLT when immunosuppression had been reliably established in the presence of HAART. One patient died 95 days after OLT due intrathoracic hemorrhage, whereas 6 patients were alive at a median of 24 months. A single episode of acute rejection was observed. The spectrum of postoperative complications was no different from HIV‐negative patients apart from Kaposis sarcoma and multicentric Castlemans disease in a single patient. Recurrent hepatitis B infection was efficiently prevented, whereas hepatitis C reinfection occurred in all 4 patients who had preexisting hepatitis C. Earlier reports on fatal courses of recurrent hepatitis C infection, high rates of organ rejection, and HAART‐related liver toxicity were not observed in our patients. In conclusion, even though preliminary, our data suggest that outcomes after liver transplantation of HIV‐infected patients can be improved. (Liver Transpl 2005;11:1515–1521.)

Estimation of Glomerular Filtration Rates After Orthotopic Liver Transplantation: Evaluation of Cystatin C-Based Equations

Early detection of renal dysfunction in patients after orthotopic liver transplantation is important. Creatinine‐based equations to estimate glomerular filtration rate (GFR) were found to be less accurate in liver transplant recipients than in their original populations. Since cystatin C (CysC) is independent from muscle mass and hepatic biosynthesis, we evaluated the diagnostic accuracy of 3 CysC‐based equations (Larson, Hoek, and Filler formulae) that are based on the same CysC method as that of our center in comparison to the abbreviated creatinine‐based modification of diet in renal disease (MDRD) formula in 59 liver transplant recipients. “True GFR” was measured by 99mTc‐diethylene triamine pentaacetic acid (99mTc‐DTPA) clearance. Neither correlation with the GFR (correlation coefficients: 0.594–0.640) nor precision (root mean square error: 15.7–18.17 mL/min/1.73 m2) differed significantly between the tested formulae. The biases of the Hoek and Larsson formulae were significantly smaller than those of the MDRD and Filler equations (−0.1 and −2.3 vs. 10.1 and 7.9 mL/min/1.73 m2, respectively; P ≤ 0.0023). Mean estimates of MDRD (61.9 ± 21.4 mL/min/1.73 m2) and Filler (61.2 ± 22.1 mL/min/1.73 m2) differed significantly from the measured GFR (52.3 ± 17.5 mL/min/1.73 m2; P < 0.005), whereas Larsson and Hoek did not (49.5 ± 20.2 and 51.4 ± 17.9 mL/min/1.73 m2, respectively). Accuracy within 30% and 50% of the true GFR was best for the Hoek (76.3% and 93.2%) formula, albeit not significantly different from MDRD (64.4% and 83.1%). Taken together, these data show the best overall performance for GFR estimates derived from the Hoek equation with respect to bias, precision, and accuracy. Liver Transpl, 2006.

Metabolic alterations to the mucosal microbiota in inflammatory bowel disease.

Background:Inflammation during inflammatory bowel disease may alter nutrient availability to adherent mucosal bacteria and impact their metabolic function. Microbial metabolites may regulate intestinal CD4+ T-cell homeostasis. We investigated the relationship between inflammation and microbial function by inferred metagenomics of the mucosal microbiota from colonic pinch biopsies of patients with inflammatory bowel disease. Methods:Paired pinch biopsy samples of known inflammation states were analyzed from ulcerative colitis (UC) (23), Crohns disease (CD) (21), and control (24) subjects by 16S ribosomal sequencing, histopathologic assessment, and flow cytometry. PICRUSt was used to generate metagenomic data and derive relative Kyoto Encyclopedia of Genes and Genomes Pathway abundance information. Leukocytes were isolated from paired biopsy samples and analyzed by multicolor flow cytometry. Active inflammation was defined by neutrophil infiltration into the epithelium. Results:Carriage of metabolic pathways in the mucosal microbiota was relatively stable among patients with inflammatory bowel disease, despite large variations in individual bacterial community structures. However, microbial function was significantly altered in inflamed tissue of UC patients, with a reduction in carbohydrate and nucleotide metabolism in favor of increased lipid and amino acid metabolism. These differences were not observed in samples from CD patients. In CD, microbial lipid, carbohydrate, and amino acid metabolism tightly correlated with the frequency of CD4+Foxp3+ Tregs, whereas in UC, these pathways correlated with the frequency of CD4+IL-22+ (TH22) cells. Conclusions:Metabolic pathways of the mucosal microbiota in CD do not vary as much as UC with inflammation state, indicating a more systemic perturbation of host–bacteria interactions in CD compared with more localized dysfunction in UC.

Liver transplantation for unresectable hepatocellular carcinoma in normal livers

BACKGROUND & AIMS The role of liver transplantation in the treatment of hepatocellular carcinoma in livers without fibrosis/cirrhosis (NC-HCC) is unclear. We aimed to determine selection criteria for liver transplantation in patients with NC-HCC. METHODS Using the European Liver Transplant Registry, we identified 105 patients who underwent liver transplantation for unresectable NC-HCC. Detailed information about patient, tumor characteristics, and survival was obtained from the transplant centers. Variables associated with survival were identified using univariate and multivariate statistical analyses. RESULTS Liver transplantation was primary treatment in 62 patients and rescue therapy for intrahepatic recurrences after liver resection in 43. Median number of tumors was 3 (range 1-7) and median tumor size 8 cm (range 0.5-30). One- and 5-year overall and tumor-free survival rates were 84% and 49% and 76% and 43%, respectively. Macrovascular invasion (HR 2.55, 95% CI 1.34 to 4.86), lymph node involvement (HR 2.60, 95% CI 1.28 to 5.28), and time interval between liver resection and transplantation < 12 months (HR 2.12, 95% CI 0.96 to 4.67) were independently associated with survival. Five-year survival in patients without macrovascular invasion or lymph node involvement was 59% (95% CI 47-70%). Tumor size was not associated with survival. CONCLUSIONS This is the largest reported series of patients transplanted for NC-HCC. Selection of patients without macrovascular invasion or lymph node involvement, or patients ≥ 12months after previous liver resection, can result in 5-year survival rates of 59%. In contrast to HCC in cirrhosis, tumor size is not a predictor of post-transplant survival in NC-HCC.