Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: UMLS:C0023890 (
cirrhosis
)
42,195
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Interferons exhibit antiviral and immunomodulatory properties. Antiviral effects appear mainly mediated via 2'5' oligoadenylate synthetase and protein kinase proteins which inhibit viral components synthesis. Interferons also influence the immune system through various mechanism among whom an increased expression of
HLA class I
antigens on hepatocyte plasma membrane and the promotion of natural killer cell activity leading to the clearance of infected hepatocytes. We report the results of various alpha interferon therapeutic regimens in 60 patients with chronic hepatitis C. In our series, 20 patients (33%) achieved a complete response but 78% of them relapsed after therapy withdrawal. Predictors of good response include young age, low serum ALT levels and mild liver injury. On the contrary,
cirrhosis
is associated with a poorer response.
...
PMID:[Chronic viral hepatitis and interferons: preliminary results in 60 patients with chronic hepatitis C and cellular mechanism of action]. 781 Feb 72
HLA class I
and class II antigens from 61 patients with posthepatitic
cirrhosis
and 29 HBsAg healthy carrier were examined by using the standard serum including 105 specificities in A, B, C, DQ and DR Loci of HLA provided by the 11th International Histocompatibility Workshop. The results showed the frequencies of HLA-B35 and DR3 were elevated in posthepatitic
cirrhosis
group as compared with the healthy control group (P < 0.001). The data showed that the frequencies of HLA-B8, C1 were significantly increased, while those of HLA--DR8 more significantly decreased in posthepatitic cirrhotic patients than in health virus carriers. Compared to the healthy controls, however, the frequencies of all 105 HLA specificities examined were identical to healthy carriers.
...
PMID:[The association of human leucocyte antigen (HLA) with posthepatitic cirrhosis]. 839 98
Haemochromatosis is a common autosomal recessive disorder of iron metabolism caused by a gene in tight linkage with
HLA class I
genes. Despite intensive research, the molecular defect and underlying biochemical anomaly are still unknown. Diabetes, a serious complication of haemochromatosis, is frequently associated with
cirrhosis
which reduces life expectancy. Its development is related to iron excess, directly or through associated liver involvement, although the precise mechanisms of iron toxicity remain unclear. New concepts concerning its pathogenesis include insulin resistance and beta-cell dysfunction which are apparent well before insulin deficiency and can be reversed if iron depletion is promptly initiated. Today, earlier recognition of iron overload through active diagnostic approaches has a direct impact in reducing the frequency of diabetes among hemochromatosis patients. Presymptomatic diagnosis in the general population and among relatives of affected subjects currently relies on the detection of increased iron stores through medical awareness and family screening. Indirect gene diagnosis with serological and molecular markers of the HLA region can be provided for relatives of proven cases. As part of a genetic counselling process, this allows the identification of at-risk subjects before the onset of iron accumulation. Isolation of the gene and identification of the metabolic defect leading to increased iron absorption may have significant implications for future diagnostic procedures and preventive strategies in haemochromatosis.
...
PMID:Diabetes and haemochromatosis: current concepts, management and prevention. 858 48
In the Mediterranean region almost all patients with hepatitis B virus (HBV)-related
cirrhosis
are anti-HBV e antigen (anti-HBeAg)-positive and carriers of HBeAg-negative virus mutants. The six members of a family who acquired HBV infection were recently studied: two siblings developed
cirrhosis
with persistence of HBeAg positivity, whereas their parents and two more siblings cleared the virus. The two cirrhotic patients showed homozygosity for
HLA class I
by phenotype, which is a rare occurrence in the general population, while the other family members were heterozygous for
HLA class I
. The sequencing analyses of the entire viral DNAs isolated from both cirrhotic patients showed that the two viral genomes were almost identical and no mutation preventing HbeAg synthesis or viral gene expression was present. These findings might suggest that homozygosity for
HLA class I
molecules might be responsible for an insufficient response to the virus, favouring chronic outcome of the infection and the long-lasting persistence of HBV populations that produce HBeAg.
...
PMID:Severe outcome of hepatitis B virus (HBV) infection and lack of HBV e antigen-defective virus emergence in patients homozygous for HLA class I alleles. 876 Apr 34
The chronic alcoholic patient is usually immunosuppressed, but the significance of this phenomenon in terms of bile duct injury is unclear. The immunoreactivity of the bile duct cells was examined in a series of 69 frozen liver biopsy specimens obtained from patients with alcoholic liver disease, comprising 29 cases of
cirrhosis
, 26 of alcoholic hepatitis, 10 cases of alcoholic fatty liver, and 4 specimens from normal livers. Liver diseases such as primary biliary cirrhosis and human hepatic allograft rejection, known to have an autoimmune basis, share the characteristic feature of damage to the bile duct epithelial cells. In both instances the damage seems to be immune mediated, but the nature of the antigens involved is not established. We used the avidin-biotin-peroxidase complex method to test in alcoholic liver disease for the expression of a battery of surface antigen markers that have been incriminated in tissue injury and are usually present in lymphoid cells but also expressed by epithelium. In this study we investigated the expression of the following molecules:
HLA class I
(ABC) and class II (HLA-DR, HLA-DP, HLA-DQ), CD29, CD45RA, CD45RO, CD56, interleukin 1 (IL-I), IL-2, IL-4, interferon (IFN-gamma), tumor necrosis factor beta, and transforming growth factor beta1 (TGF-beta1). The bile duct epithelial cells strongly expressed HLA-ABC in all cases, CD56 in 47 of 55, IL-4 in 15 of 41, TGF-beta1 in 14 of 25, and CD29 in 4 of 25 cases. The other markers including IFN-gamma, HLA-DR, HLA-DP, and HLA-DQ were not expressed by bile duct cells. The expression of
HLA class I
agrees with previous observations while the absence of class II expression does not. The expression by the bile duct epithelium of CD56 confirms our own previous report. A new observation is the finding of molecules such as IL-4, TGF-beta1, and CD29 strongly expressed in the bile ducts cells. The presence of these molecules, taken together with the lack of IFN-gamma expression, contradicts previous speculations that attributed to IFN-gamma a role in the induction of major histocompatibility antigens and adhesion molecules in immune-mediated alcoholic liver disease.
...
PMID:The antigenic heterogeneity of the bile duct epithelium in alcoholic liver disease. VA Cooperative Study Group 275. 1023 99
Hemochromatosis is a recessive disorder of iron metabolism characterized by progressive iron loading of parenchymal organs, which accounts for clinical complications such as
cirrhosis
, diabetes mellitus, cardiopathy, endocrine dysfunctions and arthropathy. Clinical complications, which usually develop after the third or fourth decade of life, can be fatal but may be prevented by phlebotomy if iron excess is detected at a very early stage. The hemochromatosis gene (HFE), located 4.5 megabases telomeric to the HLA-A locus, encodes an
HLA class I
like protein and two missense mutations, C282Y and H63D in complete disequilibrium have been identified within this gene. Due to its high frequency in the general population, the involvement of H63D in the pathogenesis of the disease remains controversial, and it might correspond to a minor mutation. Conversely, the C282Y mutation is tightly linked to the disease, as it accounts for 80 to 100% of the hemochromatosis cases in Northern Europe. The lower frequency observed, in the patients, in Italy and South of France led to imagine either the implication of other mutations or of other genes. The C282Y mutation is absent in Asia and Africa and is present in the general population with a decreasing gradient of frequency from Northern to Southern Europe. The prevalence of the disease was usually estimated to be 3% but the observed frequency of the C282Y homozygotes is 5% in our breton population raising the question of the penetrance of the disease, and consequently the use of the genotypic test for its systematic screening. As HFE encodes a membrane protein similar to
HLA class I
protein, its contribution to iron overload is not obvious. The normal protein is predicted to to be expressed at the cell surface in association with beta 2-microglobulin, a localization for which C282Y is critical as it disrupts this association. This protein has also been shown to form a stable complex with the transferrin receptor leading to a decreased affinity for transferrin. A better knowledge of its function will help to decipher iron and different metal-ions metabolism. Although the exact role of the HFE protein is unknown, the genotypic test allows the clinicians to ascertain their diagnosis and genetic counselling.
...
PMID:[Molecular genetics of hemochromatosis]. 1052 Apr 11
In immunocompetent patients, specific human leukocyte antigen (HLA) class II alleles have been associated with the severity of hepatitis C virus (HCV)-related disease, in particular, HLA-DRB1*11 has been found to exert a protective effect. The authors have analyzed the role of
HLA class I
and II alleles in determining the frequency, timing, and progression of histologically proven recurrent hepatitis C in 89 patients who underwent a liver transplant for HCV-related
cirrhosis
. In addition, the influence of HLA mismatch between donor and recipient, HCV genotype, and use of steroid pulses was also evaluated. Median patient follow up was 35 months (range 4-119). HLA-DRB1 typing was performed by genomic analysis in all cases. Liver biopsies were obtained routinely and at least at yearly intervals. Histologically proven recurrent hepatitis was observed in 46 patients (52%), 10 patients progressing to stage 5-6 fibrosis in most cases within 2 years after transplant. By univariate analysis, 3 variables, HLA-B14, HLA-DRB1*04, and HLA-DRB1 donor/recipient mismatch, showed a significant effect on time to recurrent hepatitis C disease. These parameters were included in a multivariate regression model along with HCV genotype, treatment with steroid pulses and DRB1*11. HLA-B14, HLA-DRB1*04, and HLA-DRB1 donor/recipient mismatch were confirmed to provide a significant and independent contribution to the risk of hepatitic disease recurrence. As for the severity of the disease, none of the 10 patients with stage 5-6 hepatitis carried the HLA-DRB1*11 allele, in line with what was observed in nontransplant subjects. Our results suggest that in posttransplant recurrent hepatitis C, immunogenetic factors are relevant in determining HCV infection outcome.
...
PMID:Influence of immunogenetic background on the outcome of recurrent hepatitis C after liver transplantation. 1082 62
Thrombocytopenia (TP) often accompanies chronic liver diseases. The causes are numerous and include impaired production of blood platelets, spleen sequestration, and the immune factors, e.g. antiplatelet autoantibodies. ELISA (GTI-PAKPLUS) examinations were conducted in order to estimate the rate of autoimmune thrombocytopenia occurrence in patients with thrombocytopenia in the course of chronic hepatitis (10 patients) and
liver cirrhosis
(20 patients). Blood platelet activity was also evaluated as well as the expression of platelet glycoproteins (GPIIb, GPIIIa, and GPIX) in platelets of the patients and the controls. It was observed that autoimmune TP occurred in 30% of patients with
liver cirrhosis
and in 10% of patients with chronic hepatitis, in which anti-GPIIb/IIIa, GPIa/IIa, and
HLA class I
antibodies were detected. In all patients there occurred significant/marked platelet activation with CD61P expression. Thrombocytopenia in patients showed a similar activity after thrombin stimulation to that in healthy individuals. Expression on GPIIb platelet receptors was markedly increased and GPIX decreased in patients in comparison to the controls. There was no correlation between the occurrence of certain types of anti-platelet autoantibodies and the expression of GP on thrombocytes in these patients.
...
PMID:[Autoimmune thrombocytopenia in chronic liver disease]. 1189 44
Virus variants escaping from host immunity may be implicated in the pathogenesis of hepatitis B virus (HBV) infection. In this cross-sectional study, the association was evaluated of the frequency of amino acid variation within the immunogenic epitopes of surface gene with different disease stages of chronic HBV infection. The surface gene of HBV encompassing the a determinant (amino acids 124-148) and the putative
HLA class I
restricted cytotoxic T lymphocyte (CTL) epitope (amino acids 28- 51) were amplified and directly sequenced in 33 asymptomatic carriers (Group I), 31 patients with chronic hepatitis (Group II), 22 with
cirrhosis
(Group III), and 36 with hepatocellular carcinoma (Group IV). The amino acid sequences were compared subsequently with the consensus sequences of HBV serotype adw or adr. The frequency of amino acid variation per site per sequence (FEQ) was analyzed by generalized estimating equation with Poisson model after stratification by clinical and virological features. The FEQ was 1.21% overall, and was highest in Group IV patients and in patients above 50 years of age. In contrast, nine Group IV patients aged below 50 years who were infected with serotype adw had an inversely higher FEQ than those above 50; the age effect among hepatocellular carcinoma patients was significantly different from that among non-cancerous patients (P = 0.04). Variation of amino acid clustered within a determinant and CTL epitope for serotype adw but was distributed at random for serotype adr. Mutation hotspots differed between serotypes adw and adr. The FEQ of HBV surface protein is correlated positively with advancing age and severity of liver disease, and certain variants may contribute to the persistence of HBV infection.
...
PMID:Naturally occurring hepatitis B surface gene variants in chronic hepatitis B virus infection: correlation with viral serotypes and clinical stages of liver disease. 1221 Apr 30
Hepatitis C virus (HCV) causes various grades of chronic liver disease, ranging from an asymptomatic state to
cirrhosis
. To assess genetic factors of disease severity, we selected two HCV patient groups according to the following stringent criteria: (i) asymptomatic carrier state (ASC) defined by HCV infection for more than 20 years, normal alanine aminotransferase levels for the past 5 years as well as normal liver histology and/or shape and (ii)
liver cirrhosis
(LC) as diagnosed by clinical symptoms, liver biopsy and/or ultrasonography. A total of 103 chronically infected Japanese HCV patients (43 ASC and 60 LC) were analyzed.
HLA class I
and II alleles were established using low resolution DNA typing. HLA-DRB1 and DQB1 genotypes were inferred upon polymerase chain reaction-restriction fragment length polymorphism analysis. Two hundred and one anti-HCV-negative ethnically matched controls were included. The frequencies of DRB1*12 (*1201 and *1202), DQB1*0301 and DRB3*03 alleles were higher in patients with ASC than in those with LC (odds ratio (OR) 11.23, OR 4.25, and OR 3.22, respectively). The frequency of DQB1*0503 were lower in ASC patients compared to LC patients (OR 0.05). No significant differences between groups were observed for age, sex, source of infection, HCV genotype or viral loads. Our findings establish that certain HLA class II alleles strongly influence disease progression following HCV infection.
...
PMID:Long-term follow-up of hepatitis C virus infection: HLA class II loci influences the natural history of the disease. 1269 84
1
2
Next >>