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While the pathologic mechanisms responsible for organ-specific tissue damage in primary biliary cirrhosis (PBC) remain an enigma, it has been suggested that the pathology is mediated by autoreactive T cells infiltrating the intrahepatic bile ducts. Previously, we have documented that there is 100-fold enrichment in the frequency of CD4(+) autoreactive T cells in the liver that are specific for peptides encoded by the E2 components of the pyruvate dehydrogenase complexes (PDC-E2). We have also recently characterized the first MHC class I-restricted epitope for PDC-E2, namely amino acid 159-167, a region very similar to the epitope recognized by MHC class II-restricted CD4(+) cells and by autoantibodies. The effector functions of these PDC-E2(159-167)-specific CD8(+) cytotoxic T lymphocytes (CTLs) are not well understood. We have taken advantage of tetramer technology and report herein that there is tenfold increase in the frequency of PDC-E2(159-167)-specific CTLs in the liver as compared with the blood in PBC. In addition, the precursor frequency of the CTLs in blood was significantly higher in early-stage PBC. Of interest was the fact that, upon stimulation with the peptide, the response of PDC-E2(159-167) tetramer-positive cells is heterogeneous with respect to IFN-gamma synthesis. These data, we believe for the first time, document the enrichment of autoantigen-specific CD8(+) T cells in the PBC liver, suggesting that CD8(+) T cells play a significant role in the immunopathogenesis of PBC. [ABSTRACT FROM AUTHOR]

Over the past two decades, a number of studies have failed to provide direct evidence of specific microbial chronic infection in primary biliary cirrhosis (PBC). However, a recent report suggests that there is a specific association of Chlamydia pneumoniae in patients with PBC and that C. pneumoniae or similar antigens might play a role in the pathogenesis of disease. To determine if Chlamydia infection is associated with PBC, we applied a combination of immunological and molecular approaches to investigate (a) the serological reactivity against two common Chlamydia human pathogens, C. pneumoniae and C. trachomatis, by immunoblotting, (b) the presence of Chlamydia in liver samples of patients with PBC and controls by PCR amplification of Chlamydia specific 16S rRNA and (c) the presence of Chlamydia proteins in liver samples of patients with PBC and controls by immunohistochemical staining. By immunoblotting, C. trachomatis and C. pneumoniae specific serological antibodies were found in 52/57 (91.2%) AMA positive PBC, 7/33 (21/2%) of AMA negative PBC, 1/25 (4%) PSC, 0/15 (0%) Sjorgen's syndrome and 0/20 (0%) systemic lupus erythematosus patients and 0/20 (0%) healthy volunteers at 1:200 sera dilution. PBC sera reacted to Chlamydia and E. coli lysates in western blots up to a maximum of 10 -4 dilution. However, PCR amplification of the Chlamydia specific 16S rRNA gene was negative in 25/25 PBC livers but positive in 1/4 PSC liver, 3/6 in other liver disease controls and 1/4 normal liver samples. While two commercially available specific monoclonal antibodies stained positive controls ( Chlamydia infected HEp-2 cells) they failed to detect Chlamydia antigens in PBC livers. The detection of Chlamydia specific antibodies but not Chlamydia rRNA gene and Chlamydia antigens in PBC suggests that Chlamydia infection is not involved in PBC. [ABSTRACT FROM AUTHOR]

Adamantane derivatives were constructed by the one-pot reaction of ethyl 2,4-dioxocyclohexanecarboxylate with 2-phenylethyl 2-(acetoxymethyl)acrylate or 2-(acetoxymethyl)-1-phenyl-2-propen-1-one via domino Michael reactions and a Dieckmann condensation or an aldol-type reaction (four-bond formation), This is the first one-pot construction of adamantane derivatives from cyclohexanone derivatives not involving enamines. [ABSTRACT FROM AUTHOR]

Background and Aims: Recent routine testing for anti-mitochondrial antibodies has increased the number of patients with early primary biliary cirrhosis (PBC). The prevalence and clinical significance of esophageal varices in those patients remains obscure. Methods: A systematic cohort analysis of 256 PBC patients was performed to clarify the prevalence, characteristics, and prognosis of the patients with early PBC and esophageal varices. Results: Twenty-two patients had esophageal varices at the time of diagnosis: 5.5% (12/217) with early disease of histological stage 1 or 2, and 25.6% (10/39) with advanced disease of stage 3 or 4. Immediate treatments were required for two patients with early PBC: one for bleeding varices, and the other for large varices. The overall survival of the patients with early PBC and esophageal varices at diagnosis did not significantly differ from that of patients without esophageal varices ( P = 0.66). High alkaline phosphatase (ALP) ratios (odds ratio = 2.3) and low platelet counts (odds ratio = 0.77) were significantly associated with the presence of esophageal varices in the patients with early PBC. Significant associations of these two factors with the development of esophageal varices during follow-up were also revealed (odds ratio = 1.4 and 0.88, respectively). The patients with early PBC and high ALP ratios ≥ 1.9 had significantly high risks of developing esophageal varices during follow-up ( P = 0.022). Conclusions: High ALP ratios and low platelet counts at diagnosis and decreased platelet counts during follow-up are useful predictors of esophageal varices in patients with early PBC. [ABSTRACT FROM AUTHOR]

Abstract: Aim: We evaluated the aberrant expression of cytokeratin 7 (CK-7) in hepatocytes as a marker of cholestasis and progression in primary biliary cirrhosis (PBC). Patients and Methods: The expression of CK-7 was studied by immunohistochemistry in 83 cases of PBC. This expression was compared with biochemical data, the deposition of copper-associated protein, and previous histological classifications. Results: In normal liver, CK-7 was expressed exclusively in bile duct epithelial cells (BDE). In PBC, the expression was also observed in hepatocytes. The expression pattern was classified as follows: Grade 0, BDE as in normal; Grade 1, proliferated bile ductules; Grade 2, periportal hepatocytes in addition to proliferated bile ductules; Grade 3, intralobular hepatocytes; Grade 4, the majority of hepatocytes. The grades correlated with serum bilirubin levels but not with serum levels of biliary enzymes. A discrepancy between the CK-7 grading and Ludwig’s classification was noted in cases with Stage 1 of the CK-7 grading who were considered Stage 2 or 3 in Ludwig’s classification, suggesting that cholestasis and inflammatory activity might be independent events. Conclusions: These results suggest that the aberrant expression of CK-7 in hepatocytes may be a marker of chronic cholestasis and progression in PBC. [ABSTRACT FROM AUTHOR]