Possible involvement of T helper type 2 responses to Toll-like receptor ligands in IgG4-related sclerosing disease.

We report a case of immunoglobulin G4 (IgG4)-related sclerosing disease involving the pancreas, liver and salivary glands. Massive infiltration of IgG4-expressing plasma cells was seen in the liver and submandibular lymph nodes. Interestingly, accumulation of IgG4-expressing plasma cells was also seen in the colon and terminal ileum. Peripheral blood mononuclear cells (PBMCs) isolated from this patient exhibited enhanced production of IgG4 and interleukin-10 upon stimulation with Toll-like receptor (TLR) ligands as compared with those from a healthy control. In contrast, production of tumour necrosis factor alpha and interferon gamma by PBMCs from this patient was markedly reduced. Since colonic mucosa is always exposed to TLR ligands derived from commensal organisms, the results of immunological studies suggest that enhanced T helper type 2 responses to intestinal microflora may underlie the immunopathogenesis in this patient with IgG4-related sclerosing disease.

Multiple mesoderm subsets give rise to endothelial cells, whereas hematopoietic cells are differentiated only from a restricted subset in embryonic stem cell differentiation culture.

In the developing mouse, vascular endothelial cell (EC) and hematopoietic cell (HPC) lineages are two initial cell lineages that diverge from mesodermal cells, which have been roughly subdivided into three subtypes according to their geographical location: the organizer, embryonic mesoderm in the primitive streak, and extraembryonic mesoderm during gastrulation. Although the initial progenitors that become the two lineages appear in both vascular endothelial growth factor receptor 2(+) (VEGFR2(+)) lateral and extraembryonic mesoderm, little is known about the underlying molecular events that regulate the derivation of ECs and HPCs. Here, we describe an experimental system consisting of two types of embryonic stem cell lines capable of distinguishing between organizer and the middle section of the primitive streak region. Using this system, we were able to establish a defined culture condition that can separately induce distinct types of mesoderm. Although we were able to differentiate ECs from all mesoderm subsets, however, the potential of HPCs was restricted to the VEGFR2(+) cells derived from primitive streak-type mesodermal cells. We also show that the culture condition for the progenitors of primitive erythrocytes is separated from that for the progenitors of definitive erythrocytes. These results suggest the dominant role of extrinsic regulation during diversification of mesoderm.

Biliary complications in donors for living donor liver transplantation.

OBJECTIVES: With the increasing number of living donor liver transplantations, biliary complications in donors have emerged as a major postoperative problem. The aim of the present study was to characterize the features of the biliary complications that occur in donors. METHODS: The study subjects comprised 731 consecutive patients who donated liver grafts (434 right-lobe and 297 left-lobe grafts) for transplantation at Kyoto University Hospital from July 1999 to December 2006. Donors whose biliary complications could not be cured by conservative therapy were referred for endoscopic treatment. RESULTS: Postoperative biliary complications occurred in 55 (7.5%) donors. Initially, 48 of these 55 donors had biliary leakage and 7 had biliary stricture. Subsequently, 5 of 48 donors with leakage developed biliary stricture. The respective incidences of biliary leakage and overall biliary complications were significantly higher among donors of right-lobe grafts (9.9% and 11.1%) than among donors of left-lobe grafts (1.7% and 2.4%). Among 55 donors with biliary complications, 24 were cured by conservative therapy, and 1 was converted to surgical repair due to ileus. Endoscopic treatment was successful in 24 of 30 (80%) donors treated by endoscopic retrograde cholangiography, while the remaining 6 (20%) patients underwent surgery due to difficulties with cannulation (N = 2), excessive biliary leakage (N = 2), or complete biliary obstruction (N = 2). CONCLUSIONS: Donors of right-lobe grafts have a significantly higher incidence of biliary complications than donors of left-lobe grafts. When conservative therapy fails, endoscopic treatment is effective for these complications, and should be attempted as the first-line therapy before surgical repair.

Induction and monitoring of definitive and visceral endoderm differentiation of mouse ES cells.

Preparation of specific lineages at high purities from embryonic stem (ES) cells requires both selective culture conditions and markers to guide and monitor the differentiation. In this study, we distinguished definitive and visceral endoderm by using a mouse ES cell line that bears the gfp and human IL2R alpha (also known as CD25) marker genes in the goosecoid (Gsc) and Sox17 loci, respectively. This cell line allowed us to monitor the generation of Gsc+ Sox17+ definitive endoderm and Gsc- Sox17+ visceral endoderm and to define culture conditions that differentially induce definitive and visceral endoderm. By comparing the gene expression profiles of definitive and visceral endoderm, we identified seven surface molecules that are expressed differentially in the two populations. One of the seven markers, Cxcr4, to which a monoclonal antibody is available allowed us to monitor and purify the Gsc+ population from genetically unmanipulated ES cells under the condition that selects definitive endoderm.

A multi-institution phase II study of gemcitabine/S-1 combination chemotherapy for patients with advanced biliary tract cancer.

PURPOSE: We aimed to evaluate the efficacy and safety of gemcitabine/S-1 combination chemotherapy for the treatment of patients with advanced biliary tract cancer. METHODS: Patients with histologically or cytologically confirmed unresectable or recurrent biliary tract cancer were eligible for inclusion. The primary endpoint was overall survival. Gemcitabine was administered intravenously at a dose of 1,000 mg/m(2) over 30 min on days 1 and 8, and oral S-1 was administered daily at a dose of 60 mg/m(2) on days 1-14. This schedule was repeated every 3 weeks until disease progression or patient refusal. RESULTS: Twenty-five patients were enrolled between October 2007 and January 2009. Eleven patients (44%) had extrahepatic bile duct cancer, 5 (20%) had intrahepatic bile duct cancer, 8 had gallbladder cancer (32%), and 1 (4%) had ampulla of Vater cancer. The median overall survival time was 12.7 months (95% CI, 8.4-23.5 months), and the 1-year survival rate was 52.0% (95% CI, 31.2-69.2%). Of the 23 patients with evaluable target regions, seven patients experienced a partial response, and an overall response rate was 30.4%. The following grade 3-4 hematological toxicities occurred: neutropenia (56%), leukopenia (24%), anemia (8%) and thrombocytopenia (4%). In spite of the high incidence of grade 3-4 neutropenia, no patients developed febrile neutropenia in the present study. The major grade 3-4 non-hematological toxicities were fatigue (8%), anorexia (8%) and diarrhea (4%). CONCLUSIONS: Gemcitabine/S-1 combination chemotherapy offered a promising survival benefit with acceptable toxicity in patients with advanced biliary tract cancer.

Perfusion CT is superior to angiography in predicting pancreatic necrosis in patients with severe acute pancreatitis.

BACKGROUND: We performed perfusion computed tomography (P-CT) and angiography of the pancreas in patients with severe acute pancreatitis (SAP) and compared the usefulness of these two methods in predicting the development of pancreatic necrosis. METHODS: We compared P-CT and angiography results taken within 3 days after symptom onset in 21 SAP patients. We divided the pancreas into three areas, the head, body, and tail, and examined each area for perfusion defects (via P-CT) and arterial vasospasms (by angiography). Three weeks later, all patients underwent contrast-enhanced CT to determine whether pancreatic necrosis had developed. RESULTS: Of the 21 SAP patients, 16 exhibited perfusion defects, while 17 proved positive for vasospasms in at least one area. Fourteen patients developed pancreatic necrosis. Of the 63 pancreatic areas from the 21 SAP patients, perfusion defects appeared in 25 areas (39.7%), 24 of which showed vasospasms (96.0%). Angiography showed 33 areas with vasospasms (52.4%), of which 24 showed perfusion defects (72.7%). Of the 25 areas with perfusion defects, 21 developed pancreatic necrosis (84.0%). Of the 33 areas with vasospasms, 21 developed necrosis (63.6%). Pancreatic necrosis developed only in the areas positive both for perfusion defects and for vasospasms. No areas without perfusion defect or vasospasms developed pancreatic necrosis. P-CT predicted the development of pancreatic necrosis with significantly higher accuracy than angiography. CONCLUSION: While both P-CT and angiography are useful in predicting the development of pancreatic necrosis in patients with SAP, P-CT appears to be more accurate for this purpose.

IgG4-related autoimmune pancreatitis involving the colonic mucosa.

We report a case of autoimmune pancreatitis involving the colonic mucosa. Although serum level of IgG4 was normal, computed tomography and endoscopic retrograde cholangiopancreatography showed diffuse enlargement of the pancreas and irregular narrowing of the pancreatic ducts, respectively. Colonoscopy revealed a polypoidal lesion in the ascending colon. A lymphoplasmacytic infiltration was seen both in the pancreas and in the polypoidal lesion of the colon. Furthermore, immunohistochemical analysis showed abundant IgG4-positive plasma cells in these lesions. This is the first case report of a simultaneous occurrence of autoimmune pancreatitis and a colonic polypoidal lesion, both of which are characterized with increased IgG4 responses.

Restoration of RUNX3 enhances transforming growth factor-beta-dependent p21 expression in a biliary tract cancer cell line.

RUNX3 is a candidate tumor suppressor gene localized in 1p36, a region commonly inactivated by deletion and methylation in various human tumors. To elucidate the role of RUNX3 in transforming growth factor (TGF)-beta signaling in biliary tract cancer, we transfected Mz-ChA-2 cells, which do not express RUNX3 but have intact TGF-beta type II receptor and SMAD4 genes, with the RUNX3 expression plasmid pcDNA3.1/RUNX3 or with the vector pcDNA3.1 as a control. Four Mz-ChA-2/RUNX3 clones and one control clone were obtained. Although TGF-beta1 only slightly inhibited growth of the control cells, growth inhibition and TGF-beta-dependent G(1) arrest were significantly enhanced in the RUNX3-transfected clones. None of the clones, however, exhibited apoptosis. The slightly increased TGF-beta1-induced p21 expression in the control clone was strongly enhanced in the RUNX3-transfected clones, and was accompanied by augmented decreases in the expression of cyclins D1 and E. When RUNX3 small interfering RNA was added, TGF-beta-dependent induction of p21 was reduced in the RUNX3-transfected clones. Xenografts of the clones in nude mice demonstrated that tumorigenicity was significantly decreased in the RUNX3-transfected clones in inverse proportion to the expression levels of RUNX3. Based on these results, RUNX3 is involved in TGF-beta-induced expression of p21 and the resulting induction of TGF-beta-dependent G(1) arrest.

Endoscopic treatment of biliary complications after right-lobe living-donor liver transplantation with duct-to-duct biliary anastomosis.

BACKGROUND/PURPOSE: The aims of this study were to characterize the features of the biliary complications that occur after right-lobe living-donor liver transplantation (RL-LDLT) with duct-to-duct biliary anastomosis, and to evaluate the efficacy of treating biliary complications endoscopically. METHODS: The records of 273 consecutive patients who underwent RL-LDLT with duct-to-duct biliary anastomosis from July 1999 through July 2005 at Kyoto University Hospital were reviewed to determine the overall incidence of postoperative biliary complications and the outcome of endoscopic repair of those complications. RESULTS: Biliary complications occurred in 93 (34.1%) of the patients. These complications were: 80 biliary strictures (75 anastomotic and 5 nonanastomotic) and 16 biliary leakages (5 patients with biliary leakage also had a biliary stricture); most (72%) of the anastomotic strictures were complex (i.e., fork-shaped or trident-shaped). The strictures and leakages were repaired by the endoscopic placement of multiple inside stents above the sphincter of Oddi, and by nasobiliary drainage, respectively. The procedure was successful in repairing 51 (68.0%) of the anastomotic strictures and 8 (50.0%) of the biliary leakages. CONCLUSIONS: Endoscopic stenting of the bile ducts is efficacious in treating biliary complications related to RL-LDLT with duct-to-duct biliary anastomosis and the stenting should be attempted before surgical revision of strictures and leakages.

Characterization of mesendoderm: a diverging point of the definitive endoderm and mesoderm in embryonic stem cell differentiation culture.

Bipotent mesendoderm that can give rise to both endoderm and mesoderm is an established entity from C. elegans to zebrafish. Although previous studies in mouse embryo indicated the presence of bi-potent mesendoderm cells in the organizer region, characterization of mesendoderm and its differentiation processes are still unclear. As bi-potent mesendoderm is implicated as the major precursor of definitive endoderm, its identification is also essential for exploring the differentiation of definitive endoderm. In this study, we have established embryonic stem (ES) cell lines that carry GFP gene in the goosecoid (Gsc) gene locus and have investigated the differentiation course of mesendodermal cells using Gsc expression as a marker. Our results show that mesendoderm is represented as a Gsc-GFP+ E-cadherin(ECD)+ PDGFRalpha(alphaR)+ population and is selectively induced from ES cells under defined conditions containing either activin or nodal. Subsequently, it diverges to Gsc+ ECD+ alphaR- and Gsc+ ECD- alphaR+ intermediates that eventually differentiate into definitive endoderm and mesodermal lineages, respectively. The presence of mesendodermal cells in nascent Gsc+ ECD+ alphaR+ population was also confirmed by single cell analysis. Finally, we show that the defined culture condition and surface markers developed in this study are applicable for obtaining pure mesendodermal cells and their immediate progenies from genetically unmanipulated ES cells.