Regulated expression and function of the GABA receptor in human pancreatic beta cell line and islets.

G protein-coupled receptors are seven transmembrane signaling molecules that are involved in a wide variety of physiological processes. They constitute a large protein family of receptors with almost 300 members detected in human pancreatic islet preparations. However, the functional role of these receptors in pancreatic islets is unknown in most cases.

New α- and SIN γ-retrovectors for safe transduction and specific transgene expression in pancreatic β cell lines.

Background: Viral vectors are invaluable tools to transfer genes and/or regulatory sequences into differentiated cells such as pancreatic cells. To date, several kinds of viral vectors have been used to transduce different pancreatic cell types, including insulin-producing β cells. However, few studies have used vectors derived from « simple » retroviruses, such as avian α- or mouse γ-retroviruses, despite their high experimental convenience.

Islet-reactive CD8 T cell frequencies in the pancreas, but not in blood, distinguish type 1 diabetic patients from healthy donors.

The human leukocyte antigen-A2 (HLA-A2)-restricted zinc transporter 8 (ZnT8) and other islet epitopes elicit interferon-γ secretion by CD8 T cells preferentially in type 1 diabetes (T1D) patients compared with controls. We show that clonal ZnT8-reactive CD8 T cells express private T cell receptors and display equivalent functional properties in T1D and healthy individuals. Ex vivo analyses further revealed that CD8 T cells reactive to ZnT8 and other islet epitopes circulate at similar frequencies and exhibit a predominantly naïve phenotype in age-matched T1D and healthy donors.

Human fucci pancreatic Beta cell lines: new tools to study Beta cell cycle and terminal differentiation.

Regulation of cell cycle in beta cells is poorly understood, especially in humans. We exploited here the recently described human pancreatic beta cell line EndoC-βH2 to set up experimental systems for cell cycle studies. We derived 2 populations from EndoC-βH2 cells that stably harbor the 2 genes encoding the Fucci fluorescent indicators of cell cycle, either from two vectors, or from a unique bicistronic vector.