Yoshiko Kadokawa

Fatty liver in non-alcoholic non-overweight Japanese adults: Incidence and clinical characteristics

Background and Aims: Fatty liver is not uncommon in many countries, including Japan, and is mainly caused by alcohol usage and obesity. The aim of this study was to determine the incidence and causative factors of fatty liver in Japanese adults.

Preliminary analysis of a newly proposed prognostic scoring system (SLiDe score) for hepatocellular carcinoma

Background:  The long‐term prognosis of hepatocellular carcinoma (HCC) remains poor and the prediction of survival is often difficult because of the limited liver function and frequent recurrence of HCC in most patients. Therefore, a prognostic classification of HCC should account for both tumor‐related variables and liver function.

Baseline Serum Cholesterol Is Associated with a Response to Pegylated Interferon Alfa-2b and Ribavirin Therapy for Chronic Hepatitis C Genotype 2

Background. HCV infection is associated with lipid disorders because this virus utilizes the host lipid metabolism to sustain its life cycle. Several studies have indicated that higher concentrations of serum cholesterol and LDL before treatment are important predictors of higher rates of sustained virological response (SVR). However, most of these studies involved patients infected with HCV genotype 1. Thus, we performed a multi-institutional clinical study to evaluate the impact of lipid profiles on SVR rates in patients with HCV genotype 2. Methods. A total of 100 chronic hepatitis C patients with HCV genotype 2 who received peg-IFN alfa-2b and ribavirin therapy were consecutively enrolled. The significance of age, sex, BMI, AST level, ALT level, WBC, hemoglobin, platelet count, gamma-glutamyltransferase, total cholesterol level (TC), LDL level, HCV RNA, and histological evaluation was examined for SVR using logistic regression analysis. Results. The 100 patients infected with HCV genotype 2 were divided into 2 groups, an SVR group and a non-SVR group. Characteristics of each group were subsequently compared. There was no significant difference in the level of HCV RNA, BMI, platelet, TG, or stage of fibrosis between the groups. However, there were significant differences in the levels of TC and LDL-C. In multivariate logistic regression analysis using baseline characteristics, high TC level was an independent and significant risk factor (relative risk 18.59, P = 0.015) for SVR. Conclusion. Baseline serum total cholesterol levels should be considered when assessing the likelihood of sustained treatment response following the course of peg-IFN and ribavirin therapy in patients with chronic HCV genotype 2 infection.

Correlation between histopathological findings of the liver and IgA class antibodies to 2-oxo-acid dehydrogenase complex in primary biliary cirrhosis

Although anti-mitochondrial antibody (AMA) is the characteristic serological feature of primary biliary cirrhosis (PBC), its pathogenetic role remains unclear. We tested sera from 72 Japanese patients with histologically confirmed PBC for AMA by indirect immunofluorescence, anti-pyruvate dehydrogenase complex (PDC) by enzyme inhibition assay, immunoglobulin (Ig) G class anti-PDC by ELISA, and IgG, IgM, and IgA class anti-2-oxo-acid dehydrogenase complex (2-OADC) by immunoblotting. Of the 72 sera, 60 (83%), 50 (69%), 42 (58%), and 71 (99%) were positive for AMA by immunofluorescence, enzyme inhibition assay, ELISA, and immunoblotting, respectively. There was no significant correlation between histological stages and AMA by immunofluorescence, PDC inhibitory antibodies by enzyme inhibition assay, IgG class anti-PDC antibodies by ELISA, or IgG and IgM class anti-2-OADC by immunoblotting. IgA class anti-2-OADC by immunoblotting was more frequent in stages 2–4 than in stage 1 (P = 0.0083). Of the IgA class anti-2-OADC, anti-PDC-E2 (74 kDa) and anti-E3BP (52 kDa) were more frequent in stages 2–4 than in stage 1 (P = 0.0253 and 0.0042, respectively). Further examination of histopathological findings in 53 of 72 liver biopsy specimens showed that IgA class anti-PDC-E2 and IgA class anti-E3BP were associated with bile duct loss, and IgA class anti-PDC-E2 was also associated with interface hepatitis and atypical ductular proliferation. IgA is known to be secreted into the bile through biliary epithelial cells, implying that IgA class anti-PDC-E2 and E3BP may have a specific pathogenetic role during their transport into the bile by binding to their target antigen(s) in biliary epithelial cells, and this may be followed by dysfunction and finally destruction of biliary epithelial cells. Our present results suggest that these autoantibodies against 2-OADC detected by immunoblotting may be associated with the pathogenesis and pathologic progression of PBC.

Evaluation of newly developed ELISA using "MESACUP-2 test mitochondrial M2" kit for the diagnosis of primary biliary cirrhosis.

OBJECTIVES An enzyme-linked immunosorbent assay (ELISA) using MESACUP-2 Test Mitochondria M2 kit (new-M2 ELISA) has recently become commercially available. The aim of this study was to evaluate the clinical utility of this newly developed ELISA for the diagnosis of primary biliary cirrhosis (PBC). DESIGN AND METHODS We tested the immunoreactivity of sera from 82 Japanese PBC patients to the 2-oxo-acid dehydrogenase complex (2-OADC) enzymes by indirect immunofluorescence, enzyme inhibition assay using commercially available TRACE Enzymatic Mitochondrial Antibody (M2) Assay (EMA) kit, commercial ELISAs using MESACUP Mitochondria M2 kit (old-M2 ELISA) and new-M2 ELISA, and immunoblotting on bovine heart mitochondria. RESULTS Each test gave the following positive results; antimitochondrial antibodies (AMA) by immunofluorescence in 71 (87%) out of the 82 sera, enzymatic inhibitory antibody to pyruvate dehydrogenase complex (PDC) by EMA in 61 (74%), immunoglobulin (Ig) G class anti-PDC antibody by old-M2 ELISA in 55 (67%), IgG/M/A class anti-E2 subunit of PDC (PDC-E2)/anti-E2 subunit of branched chain oxo-acid dehydrogenase complex (BCOADC-E2)/anti-E2 subunit of 2-oxoglutarate dehydrogenase complex (OGDC-E2) antibodies by new-M2 ELISA in 73 (89%), and IgG, IgM, or IgA class antibodies against at least one of the 2-OADC enzymes by immunoblotting in 82 (100%). Fifty-three of the 82 sera (65%) were all positive by these five assays. Of the 18 sera that were positive by new-M2 ELISA but negative by old-M2 ELISA, 12 were theoretically interpretable. Of the 11 sera that were negative for AMA by immunofluorescence but positive for at least one of anti-2-OADC enzymes by immunoblotting, four (36%) were positive by new-M2 ELISA, whereas only two and one sera were positive by EMA and old-M2 ELISA, respectively. CONCLUSIONS Our results indicated that the sensitivity of the newly developed new-M2 ELISA was higher than that of EMA and old-M2 ELISA, and comparable with that of immunofluorescence. However, it is still unclear whether the new-M2 ELISA could replace the conventional immunofluorescence testing for routine assay requests because six (7%) sera showed discrepant results between these two assays.

Immune thrombocytopenic purpura in patients with ulcerative colitis.

Extraintestinal manifestations of ulcerative colitis (UC) are well known, but immunologically mediated hematological diseases are relatively rare. We describe two cases of immune thrombocytopenic purpura (ITP) associated with preexisting UC. Our patients had typical symptoms of UC, and endoscopy showed pancolitis. During treatment with 5-aminosalicylic acid and steroids, severe thrombocytopenia was noted. ITP was diagnosed based on a normal to high number of megakaryocytes in the bone marrow, positive autoantibody to platelet membrane antigen, and absence of splenomegaly. Medical treatment, including increased dosage of steroids, failed to control UC and ITP in both patients. In the first patient, the platelet count recovered after colectomy, while the second patient died of a cerebral hemorrhage. We stress that a diagnosis of ITP should be considered for thrombocytopenia in patients with UC, especially those showing extensive and significant colonic inflammation, and that colectomy of UC might resolve resistant ITP.

The sperm mitochondria-specific translocator has a key role in maternal mitochondrial inheritance

The mechanism of maternal mitochondrial inheritance in animals involves the selective elimination of sperm mitochondria by the elimination factor of the egg and the sperm mitochondria‐specific factor. In vitro fertilization using sperm from isogenic mice incorporating heterospecific mitochondrial DNA (mtDNA) showed that the number of PCR positives of sperm mtDNA in two‐cell embryos was significantly increased following sperm incubation with anti‐tetratricopeptide repeat‐containing protein involved in spermatogenesis (tpis) protein, anti‐translocator of mitochondrial outer membrane (Tom) 22 and anti‐Tom40 antibodies. The treatment of fertilized eggs with EGTA and other endonuclease inhibitors increased the sperm mtDNA levels. We conclude that the elimination factor, which is probably an endonuclease, is selectively received by the tpis protein of the sperm mitochondrial outer membrane within the egg. It is then transported into the sperm mitochondria by Tom22 and Tom40, where it destroys the sperm mtDNA, establishing the maternal inheritance of mtDNA.

IgA class antibodies to 2-oxo-acid dehydrogenase complex are not predictive markers of histopathological progression in primary biliary cirrhosis

Although antimitochondrial antibody (AMA) is the characteristic serological feature of primary biliary cirrhosis (PBC), its pathogenic role remains unclear. In our previous study, we reported a positive correlation between immunoglobulin (Ig) A class anti-2-oxo-acid dehydrogenase complex (2-OADC) and histopathological stage. To determine whether the appearance of IgA class anti-2-OADC by immunoblotting represents an early marker of more aggressive disease or whether it is late finding during the disease course of PBC, we tested not only the entire IgA class but also IgA1, IgA2 and secretory IgA class anti-2-OADC in serial serum samples from 15 patients with PBC. During the median observation period of 51 months, four cases showed histopathological progression (from stage 1 to 2, stage 1 to 3, stage 1 to 4 and stage 2 to 4). There was no statistically significant correlation between the above IgA class anti-2-OADCs and histopathological progression. There was no significant correlation between histopathological stages and IgA2 class anti-2-OADC or secretory IgA class anti-2-OADC by immunoblotting. IgA class anti-2-OADC was more frequent in stages 3–4 than in stages 1–2 (p = 0.0049), but IgA1 class anti-2-OADC was more frequent in stages 1–2 than in stages 3–4 (p = 0.0232). Our present study demonstrated that serum IgA class 2-OADC was not a predictive marker of histopathological progression but was associated with the histopathological stage of PBC. Although the IgA class AMA may have a specific pathogenic role for PBC, the discrepant results between IgA and IgA1 class anti-2-OADC should be further assessed to investigate different functional activities depending on their molecular form.

Anti-extractable Nuclear Antigens (ENA) Antibodies in Patients with Chronic Hepatitis C before and after Treatment with Interferon

A high prevalence of serological markers classically associated with autoimmune hepatitis or other autoimmune diseases has been reported in patients with chronic hepatitis C. However, the prevalence of antibodies to extractable nuclear antigens (anti-ENA) are rarely reported in such patients and the effect of treatment with interferon (IFN) on their prevalence is not known. In the present study, serum samples collected from 44 patients with chronic hepatitis C and 44 patients with non-hepatitis C virus (HCV) infected liver diseases were tested for anti-ENAs (U1 RNP, Sm, Ro/SS-A, La/SS-B and Scl-70) antibodies by enzyme-linked immunosorbent assay (ELISA). In 26 patients with chronic hepatitis C who received IFN treatment, serum samples were also collected just after completion of IFN treatment, and/or at 6–40 months after completion of the treatment, and tested for these antibodies. Sixteen (36%) of 44 sera from patients with chronic hepatitis C were positive for at least one of the above anti-ENA antibodies, whereas only 7 (16%) of 44 sera from patients with non-HCV infected liver diseases were positive for such antibodies (p=0.0290). There was no significant difference in the prevalence of each of anti-ENA antibody between men and women. Results of anti-ENA antibodies in most IFN-treated patients with chronic hepatitis C did not change after treatment. However, in some cases serum anti-U1 RNP, anti-La/SS-B and anti-Scl-70 became negative or converted to the gray zone after completion of IFN treatment regardless of HCV elimination. Our results showed that the overall prevalence of anti-ENA antibodies was significantly higher in patients with chronic hepatitis C than in those with non-HCV-infected liver diseases. However, the disappearance of anti-ENA antibodies after IFN treatment in patients with chronic hepatitis C may be due to the immunomodulating effects of IFN rather than HCV elimination.

Intracellular balance of oxidative stress and cytoprotective molecules in damaged interlobular bile ducts in autoimmune hepatitis and primary biliary cirrhosis: In situ detection of 8‐hydroxydeoxyguanosine and glutathione‐S‐transferase‐pi

Aim:  Bile duct injury has been thought to be absent in autoimmune hepatitis (AIH), but recent studies have indicated that AIH patients do have bile duct injury. In this study, the intracellular balance of oxidative stress and cytoprotection in biliary epithelial cells was investigated to clarify the pathogenesis of bile duct injury in AIH.