Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019158 (hepatitis)
 30,205 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Previously bis(5-amidino-2-benzimidazolyl)methane (BABIM) was identified as a strong inhibitor of the multisystem inflammatory disease induced in Lewis rats by injection of streptococcus group A cell wall-derived peptidoglycan polysaccharide (PG-APS). A BABIM derivative, trans-bis(5-amidino-2-benzimidazolyl)ethene (BBE), has attracted attention because of striking qualitative and quantitative differences in its activities when compared with the parent compound. BBE could control destructive tibial osteitis and necrotizing granulomatous splenitis and hepatitis, regardless if given in a preventive or curative mode. The compound had little effect on synovitis, however. BABIM, on the other hand, was active against synovitis and osteitis, but not against splenic granuloma formation. To be effective, it needed to be applied in a preventive mode. BBE caused a characteristic enlargement of PG-APS-laden splenic and hepatic macrophages suggesting that those cells represent targets of the inhibitor. BBE may be a powerful tool for the study of granulomatous lesions.
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PMID:Streptococcal cell wall-induced systemic disease. Beneficial effects of trans-bis(5-amidino-2-benzimidazolyl)ethene, a novel, macrophage-directed anti-inflammatory agent. 192 7

Cytochromes P450 and UDP-Glucuronosyltransferases (UGT) are targets of microsomal autoantibodies in liver and kidney (LKM). LKM autoantibodies are observed in autoimmune hepatitis, in some patients with viral hepatitis, drug-induced hepatitis and autoimmune hepatitis as disease component of the autoimmune polyglandular syndrome type 1 (APS-1). In autoimmune hepatitis LKM antibodies are markers of autoimmune hepatitis type 2. The major target of LKM-1 antibodies is cytochrome P450 2D6; a second less frequent target was the described UGTs of family 1. In autoimmune hepatitis LKM-1 autoantibodies are usually directed against small linear epitopes. LKM autoantibodies are also associated with infection with hepatitis viruses C and D. In hepatitis C about 1-2% of patients develop LKM-1 autoantibodies. About 60% of these autoantibodies are conformation dependent. The presence of LKM autoantibodies in hepatitis C may be associated with an increased risk in interferon treatment. LKM-3 autoantibodies are found in about 8% of patients with hepatitis D and are directed against conformational epitopes. Patients treated with certain drugs may develop drug induced hepatitis. In hepatitis induced by tienilic acid, tienilic acid is activated by and covalently bound to cytochrome P450 2C9. Activation of the immune system results in the formation of autoantibodies against cytochrome P450 2C9 (LKM-2) and infiltration of the liver with immune cells. A similar mechanism has been described for dihydralazine induced hepatitis, where autoantibodies are directed against P450 1A2 (LM). Autoantibodies directed against cytochrome P450 1A2 also are found in patients suffering from hepatitis as a disease component of APS-1.
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PMID:Cytochrome P450 enzymes and UDP-glucuronosyltransferases as hepatocellular autoantigens. 911 34

Several diseases are regarded as autoimmune liver diseases. Apart from the cholestatic liver diseases, primary biliary cirrhosis, primary sclerosing cholangitis, these include autoimmune hepatitis, hepatitis as part of the autoimmune polyendocrine syndrome type 1 (APS-1) and particular overlap syndromes such as autoimmune cholangitis (also called antimitochondrial antibody negative primary biliary cirrhosis [PBC]), overlap syndrome chronic active hepatitis (CAH)/PBC and the overlap syndrome primary sclerosing hepatitis (PSC)/CAH. In addition, auto-antibodies may be observed during the course of chronic viral hepatitis, in particular chronic hepatitis C and D. Finally, a small number of drug-induced liver diseases is immune mediated. The following article will review our recent progress in the field of autoimmune hepatitis including APS-1 and autoimmunity in viral hepatitis and immune-mediated drug-induced liver disease.
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PMID:Recent developments in autoimmune liver diseases. 940 46

The mechanisms driving the immune-mediated destruction of hepatic tissues in autoimmune hepatitis (AIH) are unknown. Recently the autoimmune regulator (AIRE), a gene associated with the development of the autoimmune polyglandular syndrome type 1 (APS-1), was cloned. About 15% to 20% of APS-1 patients develop hepatitis. However, the role of AIRE mutations in AIH, primary sclerosing cholangitis (PSC), and primary biliary cirrhosis (PBC) is not known. To address this issue patients with AIH (n = 94), PSC (n = 60), and PBC (n = 30) were analyzed for the presence of mutations in exons 6, 8, and 10 of AIRE by single stranded conformation polymorphism and sequence analysis. Autoantibody patterns of patients with defects in AIRE were analyzed by indirect immunofluorescence, enzyme-linked immunosorbent assay and Western blot. Heterozygous mutations of AIRE were identified in 3 patients: a patient with PBC and a patient with AIH type 1 carried a R257X mutation, and a patient with AIH type 2, diabetes mellitus type 1 (IDDM), thyroid disease, and atrophic gastritis carried a G305S mutation in the first PHD ring finger domain of the AIRE protein. None of the 3 patients with a defective AIRE allele showed autoantibodies, which are known to associate with APS-1. These findings show a differential genetic association of autoimmune liver diseases and hepatitis in APS-1. The subgroup of patients with heterozygous mutations in AIRE does not represent patients with an incomplete APS-1 syndrome. However, the Aire gene defect showed that genes involved in the induction of immunologic tolerance provide candidates for etiologic factors in autoimmune liver diseases.
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PMID:Autoimmune regulator AIRE: evidence for genetic differences between autoimmune hepatitis and hepatitis as part of the autoimmune polyglandular syndrome type 1. 1134 30

Autoimmune polyglandular syndrome type 1 (APS-1) is an autosomal-recessive condition characterized by hypoparathyroidism, autoimmune Addison's disease, and chronic mucocutaneous candidiasis. Autoimmune hepatitis develops in 10-20% of affected patients and has a variable course ranging from asymptomatic chronic liver disease to lethal fulminant hepatic failure. Liver transplantation has been documented previously in only two patients. We report a 14-yr-old boy with APS-1 who developed acute liver failure secondary to associated autoimmune hepatitis. He did not respond to corticosteroid therapy and was successfully treated with an orthotopic liver transplant.
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PMID:Orthotopic liver transplantation for acute liver failure secondary to autoimmune hepatitis in a child with autoimmune polyglandular syndrome type 1. 1200 Apr 75

Autoimmune hepatitis (AIH) is a disease of unknown aetiology characterised by hypergammaglobulinaemia, non-organ and liver-related autoantibodies, association with HLA-DR3 or DR4 and a favourable response to immunosuppression. The current classification of AIH and the several autoantibodies/target autoantigens found in this disease are reported. The importance of these markers in the differential diagnosis and the study of pathogenesis of AIH is also given. AIH is subdivided into two major types: AIH type 1 (AIH-1) and AIH type 2 (AIH-2). AIH-1 is characterised by the detection of smooth muscle autoantibodies (SMA) and/or antinuclear antibodies (ANA). Antineutrophil cytoplasmic autoantibodies (ANCA), in most cases of perinuclear pattern (p-ANCA), by the indirect immunofluorescence assay, antibodies against the asialoglycoprotein receptor (anti-ASGP-R) and antibodies to soluble liver antigens or liver-pancreas (anti-SLA/LP) may be useful for the identification of individuals who are seronegative for ANA/SMA. AIH-2 is characterised by the presence of specific autoantibodies against liver and kidney microsomal antigens (anti-LKM type 1 or infrequently anti-LKM type 3) and/or autoantibodies against liver cytosol 1 antigen (anti-LC1). Anti-LKM-1 and anti-LKM-3 autoantibodies are also detected in some patients with chronic hepatitis C (HCV) and chronic hepatitis D (HDV). For these reasons, the distinction between AIH and chronic viral hepatitis is of particular importance. Cytochrome P450 2D6 (CYP2D6) is the major target autoantigen of anti-LKM-1 autoantibodies in both conditions (AIH-2 and HCV infection). Recent data have demonstrated the expression of CYP2D6 on the surface of hepatocytes, suggesting a pathogenetic role of anti-LKM-1 autoantibodies in liver injury. Family 1 of UDP-glycuronosyltransferases has been identified as the target autoantigen of anti-LKM-3. The molecular target of anti-SLA/LP autoantibodies has been identified recently as a 50 kDa protein with unknown structure and function. A liver-specific enzyme, the formiminotransferase cyclodeaminase, was identified as the target autoantigen of anti-LC1 autoantibodies. Anti-ASGP-R and anti-LC1 autoantibodies appear to correlate better with the severity of AIH and the response to treatment. The latter may suggest a pathogenic role of these autoantibodies in the hepatocellular damage in AIH. In general, however, autoantibodies should not be used to monitor treatment or to predict AIH activity or outcome. Finally, current knowledge concerning a specific form of AIH that may develop in some patients with a rare genetic syndrome, the autoimmune polyglandular syndrome type-1 (APS-1), is also discussed. Autoantibodies against liver microsomes (anti-LM) are the specific autoantibodies found in AIH as a disease component of APS-1. However, anti-LM autoantibodies have also been described in cases of dihydralazine-induced hepatitis. Cytochrome P450 1A2 has been identified as the target autoantigen of anti-LM autoantibodies in both disease entities.
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PMID:Autoantibodies and defined target autoantigens in autoimmune hepatitis: an overview. 1214 8

We herein report on two Japanese siblings with autoimmune polyglandular syndrome type 1 (APS-1). The brother, who expressed a characteristic phenotype of APS-1, had developed severe mucocutaneous candidiasis in early infancy and thereafter developed hypoparathyroidism and Addison's disease, along with a severe deterioration of his immunologic function. In contrast, the 44-year-old sister, who showed a noncharacteristic phenotype of APS-1, developed insulin-dependent diabetes with high anti-glutamic acid decarboxylase antibody, mild nail candidiasis, and autoimmune hepatitis with intact immunoreactivity. She had three susceptible human leukocyte antigen (HLA) loci for type 1 autoimmune diabetes. The expression of T cell receptor (TCR)V beta 5.1 increased in both patients, while the brother showed a widely suppressed expression of many TCRV beta families. Both individuals possessed compound heterozygous novel autoimmune regulator (AIRE) gene mutations (L29P and IVS9-1G > C). The same AIRE gene mutations can thus be associated with characteristic and noncharacteristic phenotypes of APS-1, and HLA may possibly influence the phenotype of APS-1.
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PMID:Distinct clinical phenotype and immunoreactivity in Japanese siblings with autoimmune polyglandular syndrome type 1 (APS-1) associated with compound heterozygous novel AIRE gene mutations. 1217 2

Autoimmune hepatitis (AIH) is a disease of unknown etiology, characterized by liver-related autoantibodies. Autoimmune hepatitis is subdivided into two major types: AIH type 1 is characterized by the detection of ANA, SMA, ANCA, anti-ASGP-R, and anti-SLA/LP. Autoimmune hepatitis type 2 is characterized to be mainly related with drug-metabolizing enzymes as autoantigens, such as anti-LKM (liver-kidney microsomal antigen)-1 against CYP2D6, anti-LKM-2 against CYP2C9-tienilic acid, anti-LKM-3 against UGT1A, and anti-LC1 (liver cytosol antigen)-1 and anti-APS (autoimmune polyglandular syndrome type-1) against CYP1A2, CYP2A6, and others. Anti-LKM-1 sera inhibited CYP2D6 activity in vitro but did not inhibit cellular drug metabolism in vivo. CYP2D6 is the major target autoantigen of LKM-1 and expressed on plasma membrane (PM) of hepatocytes, suggesting a pathogenic role for anti-LKM-1 in liver injury as a trigger. Anti-CYP1A2 was observed in dihydralazine-induced hepatitis, and radiolabeled CYP1A2 disappeared from the PM with a half-life of less than 30 min, whereas microsomal CYP1A2 was stably radiolabeled for several hours. Main antigenic epitopes on CYP2D6 are aa 193-212, aa 257-269, and aa 321-351; and D263 is essential. The third epitope is located on the surface of the protein CYP2D6 and displays a hydrophobic patch that is situated between an aromatic residue (W316) and histidine (H326). Some drugs such as anticonvulsants (phenobarbital, phenytoin, and carbamazepine) and halothane are suggested to induce hepatitis with anti-CYP3A and anti-CYP2E1, respectively. Autoantibodies against CYP11A1, CYP17, and/or CYP21 involved in the synthesis of steroid hormones are also detected in patients with adrenal failure, gonadal failure, and/or Addison disease.
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PMID:Autoantibodies against CYP2D6 and other drug-metabolizing enzymes in autoimmune hepatitis type 2. 1574 2

Autoimmune polyglandular syndrome type 1 (APS-1) is an autosomal recessive disorder characterized by chronic mucocutaneous candidiasis, autoimmune hypoparathyroidism, and primary adrenal insufficiency. It has recently been associated with mutations of a single gene found on chromosome 21, designated AutoImmune Regulator (AIRE). We report two patients with APS-1 referred to our hospital for evaluation. The first patient was an 11-year-old girl with hypoparathyroidism, infectious or immunological malabsorption, and autoimmune hepatitis. Hypoparathyroidism associated with other processes with a probable autoimmune origin suggested APS-1. Genetic study was performed revealing deletion of 13 base pairs in exon 8 of the AIRE gene. The second patient was a 17-year-old girl with autoimmune hepatitis, hypoparathyroidism, mucocutaneous candidiasis, nail dystrophy, and obliterating bronchiolitis with a probable autoimmune origin. We suspected APS-1 and genetic study was performed. The only finding was an AIRE gene polymorphism. In conclusion, the presence of a single disease criterion is sufficient to suspect APS-1 and to indicate genetic study. Further studies are required to confirm the involvement of other genes in the development of this disease.
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PMID:[AIRE gene mutation in polyglandular syndrome type 1]. 1679 67

Characterization of liver-specific autoantigens has given a fresh impetus to research in the pathogenesis of autoimmune liver diseases, viral-triggered and drug-induced autoimmunity affecting the liver. Intriguing is the fact that most of the liver-specific autoantigens are enzymes of key importance for cell's homeostasis. Detection of autoantibodies against the respective antigens is carried out for diagnostic and research purposes using indirect immunofluorescence, immunoblotting, enzyme-linked immunosorbent assays, radioimmunoassay, immunoprecipitation or assays determining inhibition of enzyme activity. In patients with autoimmune hepatitis, a liver disorder of unknown etiology and pathogenesis, disease-specific autoantibodies are frequently directed against drug metabolizing enzymes of phase 1, namely cytochrome P450 2D6 (CYP2D6). The same and other members of these families of enzymes (CYPs) have also been described as targets of liver-specific autoimmunity in chronic hepatitis C virus (HCV)-infected patients, patients with autoimmune hepatitis as part of the autoimmune polyglandular syndrome type-1 (APS-1) and drug-induced autoimmunity. How these enzymes become 'self targets' is not yet established. An antigen release following hepatocyte injury could provide the stimulus for an immune response towards epitopes on these enzymes but the highly-specific, antigen-restricted initiation of the observed autoimmune response is against such an explanation. Accordingly, in this review we will focus on the pathogenic role -if any- of autoimmune responses against liver-related CYPs in autoimmune hepatitis, HCV infection, APS-1 and drug-induced autoimmunity. Learning more about the specificity of antibody responses against these enzymes may help us better understand the mechanisms underlying liver autoimmunity and may facilitate the development of therapeutic and preventive interventions.
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PMID:Enzymes as target antigens of liver-specific autoimmunity: the case of cytochromes P450s. 1878 50


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