Shiro Fukumoto

Hepatitis B Virus with X Gene Mutation Is Associated with the Majority of Serologically "Silent" Non-B, Non-C Chronic Hepatitis

Hepatitis B virus (HBV) with X gene mutations has been a putative pathogen of chronic hepatitis without serological markers of known hepatitis viruses. The aim of this study was to reconfirm whether the HBV with the X gene mutation is associated with these serologically “silent” non‐B, non‐C (NBNC) chronic hepatitis, alcoholic liver disease (ALD) and autoimmune hepatitis (AIH). HBV DNA was amplified from serum and sequenced in 30 patients with NBNC chronic hepatitis in comparison with 20 patients with ALD and 5 patients with AIH. HBV DNA was identified in 21 patients (70%) in NBNC chronic hepatitis by nested polymerase chain reaction while only one patient (5%) in ALD and none in AIH showed HBV DNA. Eighteen (85.7%) of the 21 identified HBV DNAs had an identical 8‐nucleotide deletion mutation at the distal part of the X region. This mutation affected the core promoter and the enhancer II sequence of HBV DNA and created a translational stop codon which truncated the X protein by 20 amino acids from the C‐terminal end. All the HBV DNAs had a precore mutation at the 83rd nucleotide resulting in disruption of HBe antigen synthesis. These results indicate that HBV mutants are closely associated with the majority of serologically “silent” NBNC chronic hepatitis cases and the population of such mutant HBV DNAs is not uniform.

Effectiveness of interferon-alpha therapy in chronic hepatitis C is associated with the amount of interferon-alpha receptor mRNA in the liver

BACKGROUND/AIMS This study aimed to investigate the relationship between interferon-alpha receptor mRNA in the liver and the response to interferon therapy in chronic hepatitis C. METHODS Interferon-alpha receptor mRNA was quantified by reverse transcription polymerase chain reaction using liver biopsies from 40 patients, comprising 20 responders and 20 non-responders to subsequent interferon therapy. RESULTS The amount of interferon-alpha receptor mRNA was significantly larger in interferon-responders (0.72+/-0.12) than non-responders (0.26+/-0.08) (p<0.01). Regardless of the response to interferon, histological activity index scores and the amount of HCV-RNA showed significant inverse correlation to the amount of interferon-alpha receptor mRNA, whereas the HCV-RNA genotype was not associated with the amount of interferon-alpha receptor mRNA. Logistic analysis and multiple regression analysis showed that the amount of interferon-alpha receptor mRNA was significantly associated with the efficacy of interferon (p=0.0275), but not with fibrosis of the liver (p= 0.2726). CONCLUSIONS Our results suggest that the amount of interferon-alpha receptor mRNA is an important factor determining the response to interferon, and may be a new predictor of interferon response in chronic hepatitis C.

Expression rate of cytokine mRNA in the liver of chronic hepatitis C: comparison with chronic hepatitis B.

This study was carried out to test the hypothesis that, in chronic hepatitis (CH), inflammatory processes, including viral replication, host immune response, and hepatocyte destruction, are regulated by a cytokine network in the liver. Expression of the mRNA of the cytokines IL1-beta, IL2, IL4, IL5, IL6, TNF-alpha, and IFN-gamma, the lymphocyte markers CD4 and CD8, and the HLA class I molecule, beta 2-microglobulin (B2MG) in the liver tissue of 20 CH(C) cases and 9 CH(B) patients was investigated by the reverse transcription polymerase chain reaction (RT-PCR) method. TNF-alpha, CD4, and B2MG mRNA were detected in 100% of cases of in both CH(B) and CH(C). The expression rates of IL1-beta, IL2, IL4, IFN-gamma, and CD8 mRNA were 80%, 40%, 25%, 40%, and 80% in CH(C) and 88.9%, 44.5%, 30%, 55.6%, and 100% in CH(B). IL6 mRNA was detected only in CH(B), in 22.2% of cases, IL5 mRNA was not detected in either CH(B) or CH(C). IL2, IL4, and IFN-gamma mRNA were expressed significantly more frequently in patients who had high serum ALT and a high histological activity index (HAI) score. There was no difference in cytokine expression between CH(B) and CH(C), except in IL6, suggesting the existence of a common immunopathogenesis for CH(B) and CH(C). In chronic viral hepatitis, IL1-beta and TNF-alpha appear to play a major role in immune responses and IL2, IL4, and IFN-gamma seem to be associated with increased cytotoxic T cell response. Our results give partial support to the hypothesis that the cytokine network is important in the inflammatory process in chronic viral hepatitis in vivo.

Growth factor mRNA expression in normal colorectal mucosa and in uninvolved mucosa from ulcerative colitis patients

This study was carried out to investigate the expression of various growth factors (GFs) involved in mucosal healing and thereby to clarify whether there are potential differences in the expression of GFs between normal colonic mucosa and the uninvolved mucosa of ulcerative colitis (UC). GF mRNA was investigated by reverse transcription polymerase chain reaction in colorectal biopsies from 20 normal controls and 15 UC patients. The positive rates (%) for mRNA expression for normal/UC were: epidermal growth factor (EGF) 65/53, transforming growth factor (TGF)-α 100/87, TGF-β1 60/33, insulin like growth factor-I 45/33, platelet-derived growth factor-A 55/67, basic fibroblast growth factor 0/0, hepatocyte growth factor (HGF) 50/53, EGF receptor 20/27, erb-B2 75/73, and HGF receptor (c-MET) 55/67. Semiquantitation of mRNA showed significantly lower expression of TGF-β1 (P<0.05) in UC. Differences in expression and mRNA levels were not statistically significant for any other GFs. Our results indicate that mucosa in chronic persistent UC has a low basal expression of TGF-β1 mRNA, and, since TGF-β1 is a multifunctional GF that plays important roles in regulating repair and regeneration following tissue injury, this low expression may be partially responsible for the intractability of the disease.

Relationship between the intrahepatic expression of interferon-α receptor mRNA and the histological progress of hepatitis C virus-associated chronic liver diseases

Histological progress is one of the predictors of an unfavourable response to interferon (IFN) therapy in hepatitis C virus (HCV)‐associated chronic liver diseases (CLD). The aim of the present study was to investigate whether histological progress has an association with the expression of IFN receptor (IFN‐Rc) in the liver. Expression of mRNA of the IFN‐Rc for IFN‐α was investigated by reverse transcription polymerase chain reaction using liver biopsy specimens from 37 HCV‐associated CLD comprising 11 liver cirrhosis (LC) and 26 chronic hepatitis (CH) cases. IFN‐α and IFN‐β mRNA were detected in over 90% of subjects. In contrast, the detection rate of IFN‐Rc mRNA in chronic persistant hepatitis, chronic hepatitis 2A, chronic hepatitis 2B and liver cirrhosis (LC) was 100, 71.4, 22.2 and 0%, respectively. The absence of IFN‐Rc mRNA was significantly associated with the severity of fibrosis of the liver. These results indicated that IFN‐Rc expression decreases with the histological progress of the disease, suggesting that lower expression of IFN‐Rc mRNA may be partially responsible for the poor IFN response in LC.

Expression of interferon-alpha receptor mRNA in the liver in chronic liver diseases associated with hepatitis C virus: Relation to effectiveness of interferon therapy

To investigate whether interferon-alpha receptor (IFN-αRc) expression was related to the effectiveness of interferon therapy in hepatitis C virus (HCV)-associated chronic liver disease (CLD), IFN-αRc mRNA was investigated by reverse transcription polymerase chain reaction (RT-PCR) in liver biopsies and peripheral blood mononuclear cells (PBMCs) from 40 patients with HCV-associated CLD who subsequently received IFN-α therapy. IFN-αRc mRNA in the liver was detected in 18 of 20 (90%) responders to IFN and in 5 of 20 (25%) non-responders (P<0.01). In PBMCs, IFN-αRc mRNA was detected in all patients regardless of response to IFN. Increased histological hepatitis activity and liver fibrosis were significantly related to the absence of IFN-αRc mRNA. The HCV-RNA genotype showed no significant relationship to IFN-αRc mRNA expression. Our results suggest that IFN-αRc mRNA expression in the liver, but not in PBMCs, is closely associated with the effectiveness of IFN-α therapy in HCV-associated CLD.

Scanning electron microscopic observations of three-dimensional structure of the rat pancreatic duct.

To understand the fine, three-dimensional structure of the pancreatic duct, we made corrosion casts of rat pancreatic ducts and obtained biological specimens of rat pancreatic tissues for scanning electron microscopic observation. We observed the corrosion casts and the inner surfaces of the pancreatic duct specimens, using scanning electron microscopy. A comparative study between casts and specimens demonstrated the exactitude of our corrosion casts. These findings revealed the following facts: 1) The pancreatic ductal system had an almost tree-like shape, but parts of the intercalated ducts anastomosed with each other; 2) Intralobular ducts branched almost at a right angle from the interlobular ducts. Intercalated ducts, which branched off from the intralobular ducts, wound and forked into two branches, without any decrease in thickness. The intercellular secretory canaliculi extended from the central lumina, running straight through the center of the acini, close to the cell bases; 3) In pancreatic ducts, every lumen was covered with microvilli. The diameters of these microvilli were uniform (about 0.1 μm), but the heights were variable, even within a given pancreatic duct.

Cytokine gene expression in the gastric mucosa: its role in chronic gastritis.

There have been few studies of cytokine expression in the gastric mucosa of patients with chronic gastritis. In the present study, to elucidate the expression of cytokines in the gastric mucosa and the immunopathological roles played by these cytokines in chronic gastritis, we investigated cytokine gene expression, by reverse transcription polymerase chain reaction, in gastric biopsy specimens obtained from 29 endoscopically normal patients with chronic gastritis. The cytokines examined and the mRNA positivity were: interleukin (IL)-1β (21%), IL-2 (0%), IL-3 (7%), Il-4 (41%), IL-5 (17%), IL-6 (53%), IL-8, (98%), interferon gamma (IFN-γ) (69%), and tumor necrosis factor alpha (TNF-α) (24%). Although the histological severity of the gastritis was closely associated withHelicobacter pylori infection, the positivities of these cytokine mRNAs did not show a relationship with eitherH. pylori infection or with histological inflammation. Our findings suggest that the gastric mucosa responds to all exogenous antigens, includingH. pylori, in the same fashion immunologically, and that these cytokines do not contribute to the induction of inflammation associated withH. pylori infection.

Significance of mass survey for gastric cancer from the standpoint of surgery

From the standpoint of surgery, results for gastric cancers detected by mass survey were better than for cases found on outpatient examinations, partly because the proportion of early cancers was greater in the former group. The results for advanced cancers were also better in the mass survey group.

Fine structure of the cilia in the pancreatic duct of WBN/Kob rat

SummaryWe observed the cilia in pancreatic ducts (intraductal cilia) with scanning and transmission electron microscopy (SEM and TEM), using male WBN/Kob rats (W/K), which are the spontaneously developed chronic pancreatitis models with stasis of pancreatic juice, and male Wistar rats as control. By SEM observations, the lengths of cilia in interlobular ducts of 18-mo-old W/K were demonstrated to elongate markedly. By TEM observations in the controls, cross-sections of the intraductal cilia were demonstrated to present various numbers of microtubules (those with seven, eight, or nine microtubules accounted for 83.3% of all). There was no significant difference between W/K and controls in the number of microtubules in the cross-sections of intraductal cilia: the intraductal cilium core was provided with nine microtubules, which were different from the number of microtubules encountered within the cilium core of other ciliated cell (i.e., bronchial epithelium, and so forth), and their number in the cross-section of intraductal cilium decreased at a distal portion. Though some of their cross-sections revealed deformities of ciliary membranes and disarrangements of microtubular complex, there was no significant difference in their incidence between both rats. These findings suggest that the intraductal cilia have different functions from the ciliated cells’ cilia, and W/K has the elongated intraductal cilia without internal structural change.