Prevention of Hepatocellular Carcinoma Development Associated with Chronic Hepatitis by Anti-Fas Ligand Antibody Therapy

A persistent immune response to hepatitis viruses is a well-recognized risk factor for hepatocellular carcinoma. However, the molecular and cellular basis for the procarcinogenic potential of the immune response is not well defined. Here, using a unique animal model of chronic hepatitis that induces hepatocellular carcinogenesis, we demonstrate that neutralization of the activity of Fas ligand prevented hepatocyte apoptosis, proliferation, liver inflammation, and the eventual development of hepatocellular carcinoma. The results indicate that Fas ligand is involved not only in direct hepatocyte killing but also in the process of inflammation and hepatocellular carcinogenesis in chronic hepatitis. This is the first demonstration that amelioration of chronic inflammation by some treatment actually caused reduction of cancer development

SOCS-1/SSI-1-Deficient NKT Cells Participate in Severe Hepatitis through Dysregulated Cross-Talk Inhibition of IFN-γ and IL-4 Signaling In Vivo

AbstractSuppressor of cytokine signaling-1 (SOCS-1), also known as STAT-induced STAT inhibitor-1 (SSI-1), is a negative feedback molecule for cytokine signaling, and its in vivo deletion induces fulminant hepatitis. However, elimination of the STAT1 or STAT6 gene or deletion of NKT cells substantially prevented severe hepatitis in SOCS-1-deficient mice, while administration of IFN-γ and IL-4 accelerated its development. SOCS-1 deficiency not only sustained IFN-γ/IL-4 signaling but also eliminated the cross-inhibitory action of IFN-γ on IL-4 signaling. These results suggest that SOCS-1 deficiency-induced persistent activation of STAT1 and STAT6, which would be inhibited by SOCS-1 under normal conditions, may induce abnormal activation of NKT cells, thus leading to lethal pathological changes in SOCS-1-deficient mice

Гомосексуальный субъект в пространстве публичного: нарративное измерение камин-аута

<div><p>Background</p><p>Although <i>Helicobacter pylori</i> (<i>H</i>. <i>pylori</i>) infection is closely associated with the development of peptic ulcer, its involvement in pathophysiology in the lower intestinal tract and gastrointestinal (GI) motility remains unclear. Glucagon-like peptide-1 (GLP-1) is a gut hormone produced in the lower intestinal tract and involved in GI motility. Here, we investigated the effect of <i>H</i>. <i>pylori</i> infection on the link between GLP-1 expression and motility of the GI tract.</p><p>Methods</p><p>C57BL/6 mice were inoculated with a <i>H</i>. <i>pylori</i> strain. Twelve weeks later, the <i>H</i>. <i>pylori</i>-infected mice underwent <i>H</i>. <i>pylori</i> eradication treatment. GI tissues were obtained from the mice at various time intervals, and evaluated for the severity of gastric inflammatory cell infiltration and immunohistochemical expression of GLP-1 and PAX6 in the colonic mucosa. Gastrointestinal transit time (GITT) was measured by administration of carmine-red solution.</p><p>Results</p><p>GLP-1 was expressed in the endocrine cells of the colonic mucosa, and PAX6 immunoreactivity was co-localized in such cells. The numbers of GLP-1- and PAX6-positive cells in the colon were significantly increased at 12 weeks after <i>H</i>. <i>pylori</i> infection and showed a positive correlation with each other. The GITT was significantly longer in <i>H</i>. <i>pylori</i>-infected mice than in non-infected controls and showed a positive correlation with GLP-1 expression. When <i>H</i>. <i>pylori</i>-infected mice underwent <i>H</i>. <i>pylori</i> eradication, GITT and PAX6/GLP-1 expression did not differ significantly from those in untreated <i>H</i>. <i>pylori</i>-infected mice.</p><p>Conclusions</p><p><i>H</i>. <i>pylori</i> infection may impair GI motility by enhancing the colonic GLP-1/PAX6 expression.</p></div

Double-Stranded RNA of Intestinal Commensal but Not Pathogenic Bacteria Triggers Production of Protective Interferon-β

SummaryThe small intestine harbors a substantial number of commensal bacteria and is sporadically invaded by pathogens, but the response to these microorganisms is fundamentally different. We identified a discriminatory sensor by using Toll-like receptor 3 (TLR3). Double-stranded RNA (dsRNA) of one major commensal species, lactic acid bacteria (LAB), triggered interferon-β (IFN-β) production, which protected mice from experimental colitis. The LAB-induced IFN-β response was diminished by dsRNA digestion and treatment with endosomal inhibitors. Pathogenic bacteria contained less dsRNA and induced much less IFN-β than LAB, and dsRNA was not involved in pathogen-induced IFN-β induction. These results identify TLR3 as a sensor to small intestinal commensal bacteria and suggest that dsRNA in commensal bacteria contributes to anti-inflammatory and protective immune responses