Human Jagged 1 mutants cause liver defect in Alagille syndrome by overexpression of hepatocyte growth factor.

Alagille syndrome (AGS, MIM 118450) is an autosomal dominant inherited disease. Paucity of interlobular bile ducts is one of the major abnormalities. To explore the molecular mechanism by which mutation in the human Jagged 1 gene (JAG1, MIM 601920) causes liver defects, we investigated the gene regulation of JAG1 to hepatocyte growth factor gene (HGF).

Size-exclusion chromatography of biological samples which contain extremely alkaline proteins.

An improved size-exclusion chromatography (SEC) was developed to isolate extremely basic (alkaline) proteins, such as trypsin (pI=10.5), lysozyme (pI=11), and histone (pI=10.8).

Rum1, an inhibitor of cyclin-dependent kinase in fission yeast, is negatively regulated by mitogen-activated protein kinase-mediated phosphorylation at Ser and Thr residues.

The p25(rum1) is an inhibitor of Cdc2 kinase expressed in fission yeast and plays an important role in cell-cycle control. As its amino-acid sequence suggests that p25(rum1) has putative phosphorylation sites for mitogen-activated protein kinase (MAPK), we investigated the ability of MAPK to phosphorylate p25(rum1). Direct in vitro kinase assay using GST-fusion proteins of wild-type as well as various mutants of p25(rum1) demonstrated that MAPK phosphorylates the N-terminal portion of p25(rum1) and residues Thr13 and Ser19 are major phosphorylation sites for MAPK.

Differential graft-versus-leukaemia effect by CD28 and CD40 co-stimulatory blockade after graft-versus-host disease prophylaxis.

Co-stimulatory blockade may be a promising strategy for tolerance induction in transplantation. In allogeneic bone marrow transplantation (BMT) for leukaemia treatment, however, preservation of the graft-versus-leukaemia (GVL) effect is another critical requirement for clinical application. In this study, we have compared the effect on GVL of using CD28 and CD40 co-stimulatory blockades as graft-versus-host disease (GVHD) prophylaxis in a murine allogeneic BMT model with simultaneous transfer of BCL1 leukaemia.

[Retrograde transport of Shiga toxin 1 in human renal tubular epithelial cells].

To displays its cytotoxicity by initiating RNA cleavage, Stx1 is required to be transported from endosomes to the endoplasmic reticulum, where the translocation of the A-subunit to the cytosol occurs. In the case of established cell lines, it is reported that a large proportion of the internalized Stx is transported to lysosomes for degradation and only a fraction of the toxin molecules can reach to the cytosol. By using primary culture cells, however, we observed that Stx1 is effectively delivered to the cytosol in normal human renal tubular epithelial cells.

Analysis of the AAAS gene in a Japanese patient with triple A syndrome.

Triple A syndrome, also known as Allgrove syndrome, is a rare autosomal recessive disorder characterized by adrenal insufficiency, achalasia and alacrima. It has recently been reported that this syndrome is caused by mutations in the AAAS gene. In the present study, we analyzed the AAAS gene in a Japanese patient with triple A syndrome.

Differences in the subcellular localization of alpha1-adrenoceptor subtypes can affect the subtype selectivity of drugs in a study with the fluorescent ligand BODIPY FL-prazosin.

G protein-coupled receptor (GPCR) subtypes are differentially distributed in the cell; however, it remains unclear how this affects the subtype selectivity of particular drugs. In the present study, we used flow cytometry analysis with the fluorescent ligand, BODIPY FL-prazosin, to study the relationship between the subcellular distribution of subtype receptors and the subtype-selective character of ligands using alpha1a and alpha1b-adrenoceptors (ARs). Alpha1a-ARs predominantly localize inside the cell, while alpha1b-ARs on the cell surface.

Recent progress in alpha 1-adrenoceptor pharmacology.

The adrenoceptors (ARs) play a key role in the modulation of sympathetic nervous system activity and are a site of action for many clinically important therapeutic agents. The alpha1-adrenoceptor subtypes (alpha1A-, alpha1B-, and alpha1D-AR) play a prominent role in regulating vascular tone and hypertrophic growth of smooth muscle and cardiac cells. Their functional characteristics with respect to ligand binding and second messenger utilization have been well described.

Prolonged survival in rat liver transplantation with mouse monoclonal antibody against an inducible costimulator (ICOS).

Background: An inducible costimulator (ICOS), a recently identified costimulatory receptor with a close structural homology to CD28 and CTLA4, is expressed on activated T cells. Interaction with its ligand on antigen-presenting cells stimulates T-cell proliferation to produce a different spectrum of cytokine. The inhibition of ICOS-mediated signal transduction by an anti-ICOS antibody is considered to be capable of protecting against graft rejection in organ transplantation.

Inhibition of shiga toxin cytotoxicity in human renal cortical epithelial cells by nitrobenzylthioinosine.

Nitrobenzylthioinosine (NBTI), a nucleoside-transport inhibitor, has been found to possess the ability to prevent the cytotoxic action of Shiga toxin (Stx) 1 in human renal cortical epithelial cells (HRCECs), thereby protecting HRCECs from cell death. Further examination revealed that NBTI does not affect either the binding or the endocytosis of Stx1 but alters the intracellular transport of Stx1. Generally, endocytosed Stx1 is thought to be transported from endosomes to the endoplasmic reticulum.

A novel and de novo splice-donor site mutation in intron 3 of the GH-1 gene in a patient with isolated growth hormone deficiency.

Heterozygous mutations at the splice-donor site of inron 3 of the GH-1 gene are known to affect growth hormone (GH) mRNA splicing and cause isolated GH deficiency (IGHD), which is inherited in an autosomal dominant trait. We report here a novel and de novo heterozygous IVS3 + 6T --> G mutation of the GH-1 gene in a Japanese patient with IGHD. RT-PCR analyses of the GH-1 minigene transcripts demonstrated that the IVS3 + 6T --> G mutation causes complete skipping of exon 3.

Genomic analysis of a mouse model of immunoglobulin A nephropathy reveals an enhanced PDGF-EDG5 cascade.

The molecular mechanism of immunoglobulin A nephropathy (IgAN), the most common primary renal glomerular disease worldwide, is unknown. HIGA (high serum IgA) mouse is a valid model of IgAN showing almost all of the pathological features, including mesangial cell proliferation. Here we elucidate a pattern of gene expression associated with IgAN by analyzing the diseased kidneys on cDNA microarrays.

[Shiga toxin producing Escherichia coli infection].

Shiga toxin producing Escherichia coli(STEC) has been recognized as an emerging food-borne pathogen that causes bloody diarrhea, hemorrhagic colitis and hemolytic uremic syndrome(HUS), especially in developed countries. As the specific therapy for STEC infection has not been developed, currently available medical therapy is inadequate to prevent life-threatening complications. Here are described the possibilities and problems of using and developing therapies such as antibiotics, Synsorb-Pk and humanized anti-Stx monoclonal antibody therapy.

Genome medicine promised by microarray technology.

The human genome project has now been completed, which markedly changes the way to analyze gene functions. Recently developed DNA microarray technologies enable us to explore genome-wide gene expression in the diseased tissues. In this review, we introduce the principles and applications of microarray technologies (such as DNA, tissue and cell microarrays) to molecular diagnostics, drug target discovery and validation of drug effects.

The alpha(1D)-adrenergic receptor directly regulates arterial blood pressure via vasoconstriction.

To investigate the physiological role of the alpha(1D)-adrenergic receptor (alpha(1D)-AR) subtype, we created mice lacking the alpha(1D)-AR (alpha(1D)(-/-)) by gene targeting and characterized their cardiovascular function. In alpha(1D)-/- mice, the RT-PCR did not detect any transcript of the alpha(1D)-AR in any tissue examined, and there was no apparent upregulation of other alpha(1)-AR subtypes. Radioligand binding studies showed that alpha(1)-AR binding capacity in the aorta was lost, while that in the heart was unaltered in alpha(1D)-/- mice.

Prolongation of transgene expression by coexpression of cytokine response modifier a in rodent liver after adenoviral gene transfer.

The short duration of expression of the transgenes is a major barrier to the clinical application of adenovirus-mediated gene therapy for hepatic enzyme deficiencies. Previous reports show that Fas-mediated apoptosis has a pivotal role in the rapid elimination of adenovirus-infected hepatocytes. After considering this result and our recent observation that murine hepatocytes can be protected from Fas-mediated apoptosis by expressing cytokine response modifier A (CrmA) in vivo, we hypothesized that CrmA coexpression could also prevent adenovirus-infected hepatocytes from rapid elimination and that this would make prolonged transgene expression achievable in vivo.

Distinct pathways of apoptosis triggered by FTY720, etoposide, and anti-Fas antibody in human T-lymphoma cell line (Jurkat cells).

2-amino-2-[2-(4-octylphenyl)ethyl] propane-1,3-diol hydrochloride (FTY720), a synthetic product derived from a metabolite of Isaria sinclairii, has been demonstrated to have a potent immunosuppressive activity that induces apoptotic cell death in T cells and several other cell lines. In this study, using the human T-lymphoma cell line, Jurkat cells, we investigated the apoptotic signal transduction mediated by FTY720, in particular comparing its role on the cleavage of caspases, with that mediated by etoposide or anti-Fas antibody. All of these agents cleaved caspases, inducing their active form in the affected cells.