Decreases in both b-cell function and number can contribute to insulin deficiency in type 2 diabetes. Here, we quantified the b-cell mass in pancreas obtained at autopsy of 57 type 2 diabetic (T2D) and 52 non-diabetic subjects of European origin. Sections from the body and tail were immunostained for insulin. The b-cell mass was calculated from the volume density of b-cells (measured by point-counting methods) and the weight of the pancreas. The pancreatic insulin concentration was measured in some of the subjects. b-cell mass increased only slightly with body mass index (BMI). After matching for BMI, the b-cell mass was 41% (BMI < 25) and 38% (BMI 26-40) lower in T2D compared with non-diabetic subjects, and neither gender nor type of treatment influenced these differences. b-cell mass did not correlate with age at diagnosis but decreased with duration of clinical diabetes (24 and 54% lower than controls in subjects with <5 and >15 years of overt diabetes respectively). Pancreatic insulin concentration was 30% lower in patients. In conclusion, the average b-cell mass is about 39% lower in T2D subjects compared with matched controls. Its decrease with duration of the disease could be a consequence of diabetes that, with further impairment of insulin secretion, contributes to the progressive deterioration of glucose homeostasis. We do not believe that the small difference in b-cell mass observed within 5 years of onset could cause diabetes in the absence of b-cell dysfunction.

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Tryptophan catabolism by indoleamine 2,3-dioxygenase 1 (IDO1) plays a key role in tumoral resistance to immune rejection. In humans, constitutive expression of IDO1 has been observed in several tumor types. However, a comprehensive analysis of its expression in normal and tumor tissues is still required to anticipate the risks and potential benefits of IDO1 inhibitors. Using a newly validated monoclonal antibody to human IDO1, we performed an extensive immunohistochemical analysis of IDO1 expression in normal and tumor tissues. In normal tissues, IDO1 was expressed by endothelial cells in the placenta and lung and by epithelial cells in the female genital tract. In lymphoid tissues, IDO1 was expressed in mature dendritic cells with a phenotype (CD83 þ ,

Large A(z) values for elasticity (>0.990 for scores > or = F2, > or = F3, and F4) show that MR elastography was accurate in liver fibrosis staging and superior to biochemical testing with APRIs.

Among neonates with hyperinsulinism, about half may have focal islet-cell hyperplasia that can be treated with partial pancreatectomy. These neonates can be identified through pancreatic catheterization and intraoperative histologic studies.

†Université catholique de Louvain, Radiodiagnostic, Cliniques universitaires St-Luc, B-1200, Brussels, Belgium ‡Université catholique de Louvain, Anatomo-pathology, Cliniques universitaires St-Luc, B-1200 Brussels, BelgiumIt is currently accepted that adult tissues may develop and maintain their own stem cell pools. Because of their higher safety profile, adult stem cells may represent an ideal candidate cell source to be used for liver cell therapies. We therefore evaluated the differentiation potential of mesenchymal-like cells isolated from adult human livers. Mesenchymal-like cells were isolated from enzymatically digested adult human liver and expanded in vitro. Cell characterization was performed using flow cytometry, RT-PCR, and immunofluorescence, whereas the differentiation potential was evaluated both in vitro after incubation with specific media and in vivo after intrasplenic transplantation of uPA +/+ -SCID and SCID mice. Adult-derived human liver mesenchymal-like cells expressed both hepatic and mesenchymal markers among which albumin, CYP3A4, vimentin, and α-smooth muscle actin. In vitro differentiation studies demonstrated that these mesenchymal-like cells are preferentially determined to differentiate into hepatocyte-like cells. Ten weeks following intrasplenic transplantation into uPA +/+ -SCID mice, recipient livers showed the presence of human hepatocytic cell nodules positive for human albumin, prealbumin, and α-fetoprotein. In SCID transplanted liver mice, human hepatocyte-like cells were mostly found near vascular structures 56 days posttransplantation. In conclusion, the ability of isolated adult-derived liver mesenchymal stem-like cells to proliferate and differentiate into hepatocyte-like cells both in vitro and in vivo leads to propose them as an attractive expandable cell source for stem cell therapy in human liver diseases.Key words: Stem cells; Transplantation; SCID mice; Differentiation; Cell therapy INTRODUCTIONattention because of their proliferative potential, their ability to (trans)differentiate into mature functional hepatocytes, and their potentially lower immunogenicity. Liver cell transplantation (LCT) has emerged as a promising alternative to whole liver transplantation (17).Beside fetal liver, evidence has been accumulated to point out the presence of stem cells into the mammalian We and others have demonstrated that LCT can be beneficial in patients with inborn errors of liver metabolism adult liver. Data obtained from injured animal models have led to identify different cell types, some of them (6,8,16,30,32,34). Recently, we demonstrated in an arginino-succinate lyase deficiency patient a correlation candidate progenitor cells for liver regeneration. Studies regarding adult liver stem cells have mostly focused on between metabolic improvement, recovery of the deficient enzyme activity, and engraftment of donor hepatooval cells as well as hematopoietic and mesenchymal cells from bone marrow origin. Oval cells are localized cytes in the recipient's liver (33). However, t...

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