Publications by authors named "Ikuko Haruta"

Objectives: Autoimmune pancreatitis (AIP) is a chronic fibro-inflammatory disease of the pancreas constituting, in part, a recently defined nosological entity of IgG4-related systemic sclerosing diseases. The pathogenetic factors of AIP have not been fully elucidated. We previously established a mouse model of AIP using chronic exposure to a commensal bacteria, Escherichia coli.

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Aim: The aim of this study was to elucidate the clinical and histological features, response to corticosteroid therapy and long-term outcome of primary biliary cirrhosis (PBC) with features of autoimmune hepatitis (AIH).

Methods: Among 280 PBC patients under ursodeoxycholic acid administration, we identified 28 patients with AIH features fulfilling the following criteria: sustained high levels of serum aminotransferases and high immunoglobulin G levels with positivity for antinuclear antibodies or anti-smooth muscle antibodies (ASMA) and/or histological features of moderate to severe interface hepatitis or moderate to severe lobular hepatitis. We analyzed PBC patients with AIH features, focusing mainly on therapeutic responses to corticosteroids.

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Outer membrane protein A (OmpA) is a major outer membrane protein of Escherichia coli and other Enterobacteriaeae. Although the structural features of OmpA have been well studied, its roles in the pathogenesis of various bacterial infections have not been fully elucidated. Here, we report the generation of mouse monoclonal antibody (MAb) 49.

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Background: We previously reported a mouse model of primary biliary cirrhosis (PBC)-like chronic nonsuppurative destructive cholangitis (CNSDC), in which frequent injections of Streptococcus intermedius induced CNSDC and autoantibody production. The present study was performed to verify the model by examining 1) the reappearance of the PBC-like CNSDC after lymphocyte transfer from model to naïve mice, 2) the involvement of autophagy, and 3) the influence of the strain difference.

Methods: Mice were inoculated with S.

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The etiopathogenesis of many autoimmune disorders has not been identified. The aim of this paper is to focus on the involvement of bacterial exposure, as an environmental factor, in the pathogenesis of autoimmune pancreatitis (AIP), which is broadly categorized as autoimmune disorders involving pancreatic lesions. Avirulent and/or commensal bacteria, which may have an important role(s) as initiating/progressing factors in the pathogenesis of autoimmune disorder AIP, will be emphasized.

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The etiopathogenesis of many autoimmune disorders has not been identified. The aim of this paper is to focus on the involvement of bacterial exposure in the pathogenesis of primary biliary cirrhosis (PBC) and autoimmune pancreatitis (AIP), both of which are broadly categorized as autoimmune disorders involving hepatobiliary-pancreatic lesions. Avirulent and/or commensal bacteria, which may have important role(s) as initiating factors in the pathogenesis of autoimmune disorders such as PBC and AIP, will be emphasized.

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To elucidate whether leukocyte cell-derived chemotaxin 2 (LECT2) controls the progression of staphylococcal enterotoxin A (SEA)-induced toxicity, we examined the role of LECT2 in a mouse model. Almost all the C57BL/6J (B6) mice survived for 72 h after the injection of 0.1 μg of SEA and 20 mg of d-galactosamine (d-GalN).

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The pathogenesis of autoimmune pancreatitis (AIP) remains unknown. Here, we investigated the possible involvement of chronic, persistent exposure to avirulent bacteria in the pathogenesis of AIP. C57BL/6 mice were inoculated with heat-killed Escherichia coli weekly for 8 weeks.

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Objectives: We previously reported the finding that pancreatic stellate cells (PSCs) have a phagocytic function. The aim of the present study was to investigate whether engulfment of gram-positive bacteria by PSCs plays any role in the pathogenesis of pancreatic fibrosis.

Methods: Rat PSCs were cultured with lipoteichoic acid (LTA) or bacteria and analyzed for α-smooth muscle actin expression and collagen secretion.

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Bacterial infection has become a focus of attention in the pathogenesis of primary biliary cirrhosis (PBC). We earlier reported that the bacterial lipoteichoic acid was detected at the sites of inflammation around damaged bile ducts in the livers of PBC, and PBC patients' sera showed high titers against streptococcal histone-like protein. Here, we investigated whether chronic bacterial exposure could trigger PBC-like epithelial cell damage in normal mouse.

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Aim: To clarify the usefulness of colestimide in patients with nonalcoholic steatohepatitis (NASH) with hyperlipidemia.

Methods: In an open-label randomized controlled trial, 17 NASH patients with hyperlipidemia received colestimide (3 g/day) for 24 weeks. There were 21 control patients.

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Bacterial infection has become a focus of attention in the pathogenesis of primary biliary cirrhosis (PBC). It was reported that anti-histone autoantibody was detected in PBC, suggesting that bacterial histone-like DNA-binding protein (HLP) may be involved in the pathogenesis of PBC. To identify bacterial species in PBC to confirm this possibility, serum reactivity to bacterial cells was studied by ELISA.

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Autoimmune disorder and associated multifocal organ inflammations such as dry gland syndrome are occasionally observed; however, their etiologies are not clearly understood. We previously reported that chronic colitis-harboring TCR alpha(-/-) x AIM(-/-) mice show primary biliary cirrhosis (PBC)-like bile duct damage in the liver. Gram-positive bacterial infection is one of the candidates for the pathogenesis of PBC.

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Background: Crohn's disease and ulcerative colitis (UC) are the two main entities involved in human inflammatory bowel disease (IBD). However, their precise etiologies remain unclear. To study the development of mucosal inflammation, and chronic inflammation-based dysplasia and carcinoma formation, we examined possible roles of the apoptosis inhibitor expressed by macrophages (AIM) in an experimental IBD model.

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Background: Chronic colitis-harboring TCRalpha(- / - ) x AIM(- / - ) mice showed PBC-like bile duct damage in the liver. Bacterial infection is one of the candidates for the pathogenesis of PBC. We demonstrated that the bacterial cell wall component lipotheicoic acid (LTA) was detected at sites of inflammation around damaged bile ducts in PBC patients.

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Spur cell anemia is an acquired hemolytic anemia, which may occur in patients with severe liver dysfunction, especially in those with alcoholic cirrhosis. Recently, non-alcoholic steatohepatitis (NASH) has been highlighted as one of the causes of chronic liver diseases, which could progress to cirrhosis. Histological features of NASH are indistinguishable from those of alcoholic hepatitis.

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Aim: Intrahepatic bile ducts are the targets for inflammation in primary biliary cirrhosis (PBC), but their pathogenesis is not known. Gram-positive bacterial DNA was detected recently in gallbladder bile of PBC patients. In the present study, we assessed the possible pathological role of lipoteichoic acid (LTA), the gram-positive bacterial cell wall component, in PBC.

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Background: Intrahepatic bile ducts are the target for inflammation in both primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC). The mechanisms of biliary epithelial cell damage in both diseases are not clearly understood. Ulcerative colitis (UC) is one of the known complications in PSC.

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Integrin binding to physiologic ligands requires divalent cations and an inside-out-driven switch of the integrin to a high-affinity state. Divalent cations at the metal ion-dependent adhesion site (MIDAS) face of the alpha subunit-derived A domain provide a direct bridge between ligands and the integrin, and it has been proposed that activation dependency is caused by reorientation of the surrounding residues relative to the metal ion, forming an optimal binding interface. To gain more insight into the functional significance of the protein movements on the MIDAS face, we raised and characterized a murine mAb 107 directed against the MIDAS face of the A domain from integrin CD11b.

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