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1.
Eur J Immunogenet ; 28(3): 425-8, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11422420

ABSTRACT

Although the aetiology of chronic fatigue syndrome is controversial, evidence that infective agents including viruses may have a role in the development of the condition has led to studies seeking an association with the immunomodulatory HLA genes. In the present study, we sought to extend previous work using a well-characterized patient group and modern HLA genotyping techniques. Fifty-eight patients were phenotyped for HLA A and B by microcytotoxicity and genotyped for HLA DRB, DQB and DPB by PCR oligoprobing, and the frequencies of antigens so assigned were compared with those from a control group of 134. No significant differences in HLA frequencies were found between patient and control groups. Thus, this study does not confirm previous findings of an HLA association with chronic fatigue syndrome, suggesting that neither presentation of viral antigen by HLA class I nor antigen processing genes in the HLA region is a major contributory factor in the development of the disease.


Subject(s)
Fatigue Syndrome, Chronic/genetics , Genotype , Alleles , Female , HLA-A Antigens/genetics , HLA-B Antigens/genetics , HLA-DP Antigens/genetics , HLA-DQ Antigens/genetics , HLA-DR Antigens/genetics , Humans , Male , Phenotype
2.
Liver ; 20(3): 234-9, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10902974

ABSTRACT

AIMS/BACKGROUND: Recent evidence suggests that spontaneous clearance of hepatitis C virus (HCV) may be associated with the HLA DQB1*0301 allele but there is still some debate over the role of other alleles and HLA haplotypes in HCV infection. As this may best be resolved by studying genetically different populations, we have investigated HLA class II-encoded susceptibility and resistance to HCV infection in a relatively sedentary population of patients from northwestern Poland. METHODS: The distributions of HLA class II DRB1, DQA1, DQB1 and DPB1 alleles were determined by standard PCR-protocol in 129 unrelated patients with chronic hepatitis C (anti-HCV and HCV-RNA positive) and 103 healthy unrelated racially-matched control subjects. Fifty-five patients were treated with alpha-interferon (5 MIU thrice weekly for 6 months) out of whom 29 showed a complete response and 26 were non-responders. RESULTS: A significantly reduced frequency of the DQB1*0301 allele in the patients was observed (24.0% vs. 38.8%; p=0.015). Additionally, two different DR-DQ haplotypes were found to be associated with chronic HCV infection: DRB1*1501-DQA1*01-DQB1*0602 (24.0% vs. 12.6%; p= 0.027) and DRB1*0701-DQA1*0201-DQB1*02 (31.8 vs. 12.6%; p=0.0006), the latter difference being most pronounced in those patients who responded to alpha-interferon treatment (41.4% vs. 12.6%; p=0.00048). CONCLUSIONS: The results confirm the negative association between chronic HCV and DQB1*0301 and identify two novel genetic associations. In particular, the DRB1*0701-DQA1*0201-DQB1*02 haplotype is associated with both chronic infection and response to alpha-interferon. Interestingly, the same haplotype is reportedly associated with non-response to hepatitis B vaccination.


Subject(s)
Genes, MHC Class II , HLA-DR Antigens/genetics , Haplotypes , Hepatitis C, Chronic/drug therapy , Hepatitis C, Chronic/immunology , Interferon-alpha/therapeutic use , Adult , Aged , DNA/analysis , DNA Probes, HLA/chemistry , Female , Gene Frequency , Genetic Predisposition to Disease , Hepacivirus/drug effects , Hepacivirus/isolation & purification , Hepatitis C Antigens/blood , Hepatitis C, Chronic/virology , Histocompatibility , Humans , Immunity, Innate/genetics , Male , Middle Aged , Poland , Polymerase Chain Reaction , Treatment Outcome
3.
Hepatology ; 30(4): 851-6, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10498633

ABSTRACT

Genetic involvement in type 1 autoimmune hepatitis (AIH) is indicated by a marked female preponderance and strong, well-established, human leukocyte antigen (HLA) associations. These associations, however, are not universal and a number of genes outside the major histocompatibility complex may also play a role in susceptibility to type 1 AIH. Prime candidates at present are those polymorphic genes encoding the proinflammatory and immunoregulatory cytokines. The aim of this study was to investigate, for the first time, 2 members of the interleukin-1 (IL-1) family (IL-1B and IL-1RN), 3 polymorphic sites in the interleukin-10 (IL-10) gene promoter (positions -1082, -819, and -592), and 2 polymorphisms in the tumor necrosis factor-alpha (TNF-alpha) promoter (positions -308 and -238) in type 1 AIH. The study was performed on 2 independently collected DNA banks, each with appropriate controls, and throughout the analysis associations described in the first set were confirmed in the second set. Standard polymerase chain reaction (PCR)-based genotyping techniques were used. Overall there were no significant differences in the distributions of the IL-1B and IL-10 alleles, genotypes, or haplotypes in either study set. In contrast we report a significant association between type 1 AIH and TNF*2 (first set: 34% of controls vs. 49% of patients, Pc =.014 and second set: 26% vs. 56%, P =.00008). However, TNF*2 is found in strong linkage disequilibrium with the HLA A1-B8-DR3 haplotype and stratification analysis indicates that the association with TNF*2 is interdependent with HLA DRB1*0301. This is an indication that there is more than one susceptibility allele for type 1 AIH on chromosome 6p21.3.


Subject(s)
Cytokines/genetics , Hepatitis, Autoimmune/genetics , Polymorphism, Genetic/genetics , Adolescent , Adult , Aged , Alleles , Female , Genetic Linkage , Genetic Predisposition to Disease/genetics , Genotype , HLA-B8 Antigen/genetics , Humans , Interleukin 1 Receptor Antagonist Protein , Interleukin-1/genetics , Interleukin-10/genetics , Male , Middle Aged , Promoter Regions, Genetic/genetics , Reference Values , Sialoglycoproteins/genetics , Tumor Necrosis Factor-alpha/genetics
4.
Gastroenterology ; 117(3): 645-52, 1999 Sep.
Article in English | MEDLINE | ID: mdl-10464141

ABSTRACT

BACKGROUND & AIMS: Polymorphisms that control cytokine production can affect immunoregulation. The frequency and consequences of these polymorphisms in type 1 autoimmune hepatitis were determined. METHODS: DNA samples from 155 patients and 102 ethnically similar normal individuals were assessed by polymerase chain reaction for polymorphisms of 4 different cytokine-producing genes. RESULTS: Only genotypes associated with the guanine to adenine substitution at position -308 of the tumor necrosis factor gene occurred more commonly in patients than in normal subjects (56% vs. 26%; P < 0.001). Patients with this polymorphism had the HLA DRB1*0301 allele (81% vs. 10%; P < 0.000001) and A1-B8-DRB1*0301 (66% vs. 0%; P < 0.000001) phenotype more frequently and HLA DRB1*04 alleles less often (24% vs. 67%; P < 0.000001). They also entered remission less commonly (56% vs. 78%; P = 0.01), had treatment failure more often (20% vs. 7%; P = 0.03), and developed cirrhosis more frequently (40% vs. 19%; P = 0.05). These latter differences, however, were not statistically significant by adjusted P value. CONCLUSIONS: A polymorphism of the tumor necrosis factor gene occurs more commonly in patients with type 1 autoimmune hepatitis than in normal subjects; it is associated with a poorer response to corticosteroids. The polymorphism may be inherited as part of the extended A1-B8-DRB1*0301 haplotype and may affect both disease expression and behavior.


Subject(s)
Cytokines/genetics , Hepatitis, Autoimmune/immunology , Adolescent , Adult , Aged , Autoantibodies/analysis , Cytokines/biosynthesis , DNA/analysis , Female , Genotype , Glucocorticoids/therapeutic use , HLA-D Antigens/genetics , Hepatitis, Autoimmune/drug therapy , Hepatitis, Autoimmune/genetics , Hepatitis, Autoimmune/physiopathology , Humans , Immunosuppressive Agents/therapeutic use , Male , Middle Aged , Polymerase Chain Reaction , Polymorphism, Genetic , Prednisone/therapeutic use , Treatment Outcome , Tumor Necrosis Factor-alpha/genetics
5.
J Clin Endocrinol Metab ; 84(3): 1056-60, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10084595

ABSTRACT

Premature ovarian failure (POF) has an autoimmune pathogenesis in a significant proportion of cases. Autoantibodies to the steroid cell enzyme, 3beta-hydroxysteroid dehydrogenase (3betaHSD) are present in one fifth of patients and may identify an autoimmune subgroup. As autoimmune diseases are associated with alleles of the human leukocyte antigen (HLA) genes, we examined the distribution of HLA-DRB1 and -DQB1 genotypes in 118 women with POF, of whom 21% had 3betaHSD autoantibodies, and 134 racially matched control subjects. Two HLA-DQB1 alleles, 0301 and 0603, were associated with 3betaHSD autoantibody positivity (P = 0.04 and P = 0.006, respectively). As the DQB1*0301 and -0603 genes share an identical codon at position 57 (aspartate, Asp), we analyzed the frequency of DQbeta-Asp57 encoding DQB1 genes in our series. Eighteen of 21 POF patients with 3betaHSD autoantibodies had DQbeta-Asp57-encoding genotypes (haplotype frequency, 27 of 42; 64%) compared with 92 of 134 control subjects (haplotype frequency, 109 of 268; 41%; P = 0.004), and 9 of 21 (43%) cases were homozygous for codon 57 genotypes compared with 17 of 134 (13%) control subjects (P = 0.0006). These probability values were not significant after correction for multiple testing, and these trends will therefore require confirmation in larger cohorts. HLA class II molecules present antigenic peptides to CD4+ T lymphocytes. DQbeta57 occupies a key site at the boundary of the peptide binding groove, with a major impact on peptide binding. Our preliminary demonstration of an association between POF, 3betaHSD autoimmunity, and a distinctive HLA-DQ molecule supports the hypothesis that autoantibodies to this steroid cell enzyme may be markers of autoimmune ovarian failure and suggests that presentation of autoantigenic or external peptides to T lymphocytes by HLA-DQ molecules with Asp57-beta-chains is important in the pathogenesis of this disease.


Subject(s)
3-Hydroxysteroid Dehydrogenases/immunology , Aspartic Acid/genetics , Autoimmunity/genetics , HLA-DQ Antigens/genetics , Primary Ovarian Insufficiency/genetics , Primary Ovarian Insufficiency/immunology , Amino Acid Sequence/genetics , Autoantibodies/analysis , Autoimmunity/immunology , Female , Genotype , HLA-DQ Antigens/analysis , HLA-DQ beta-Chains , HLA-DR Antigens/analysis , Humans , Thyroglobulin/immunology , Thyroid Gland/immunology
6.
Schizophr Res ; 32(2): 75-80, 1998 Jul 27.
Article in English | MEDLINE | ID: mdl-9713901

ABSTRACT

Patients with schizophrenia rarely develop rheumatoid arthritis, an autoimmune disease that exhibits genetic association with the HLA DRB1*04 gene. We previously investigated the hypothesis that schizophrenia is negatively associated with DRB1*04, and found that only half the expected number of schizophrenic patients had this gene when compared with controls. We now report the results of DRB1*04 genotyping in pedigrees multiply affected with schizophrenia. Polymerase chain reaction amplification and sequence-specific oligonucleotide probes were used to determine the DRB1 genotypes of the 187 members of 23 pedigrees multiply affected with RDC schizophrenia. DQA1, DQB1 and DPB1 genotypes were similarly determined. We analysed data using the extended transmission/disequilibrium test and found a trend for the preferential non-transmission of DRB1*04 alleles from heterozygous parents to their schizophrenic offspring (16 of 23 alleles not transmitted, chi 2 = 3.5, p = 0.06). We found no evidence for a gene of major effect using GENEHUNTER for parametric and non-parametric linkage analysis. The results from this small sample need to be interpreted with caution, but they are in keeping with previous reports and suggest that HLA DRB1*04 alleles may be associated with a reduced risk of schizophrenia.


Subject(s)
Chromosomes, Human, Pair 6/genetics , HLA-DR Antigens/genetics , Linkage Disequilibrium/genetics , Schizophrenia/genetics , Alleles , Chromosome Mapping , Genotype , HLA-DRB1 Chains , Humans , Pedigree , Polymerase Chain Reaction
7.
Am J Psychiatry ; 153(12): 1530-3, 1996 Dec.
Article in English | MEDLINE | ID: mdl-8942447

ABSTRACT

OBJECTIVE: The authors investigated the human leukocyte antigen (HLA) DRB1*04 gene in schizophrenic patients because it is positively associated with rheumatoid arthritis, an autoimmune disease that exhibits a strong negative association with schizophrenia. The HLA DQB1*0602 allele was also studied because of previous reports of genetic association between it and schizophrenia. Maternal HLA was investigated because of the reported association between prenatal influenza and schizophrenia and the central role of HLA molecules in the immune response to viral infections. METHOD: Polymerase chain reactions and sequence-specific oligonucleotide probes were used to genotype 94 unrelated patients with DSM-III-R schizophrenia, 92 mothers of schizophrenic offspring who were not related either to each other or to the 94 patients, and 177 healthy comparison subjects. RESULTS: The frequency of DRB1*04 alleles was significantly lower in both the schizophrenic patients and the unrelated mothers of schizophrenic offspring than in the healthy comparison subjects. No significant differences were found for DQB1*0602. CONCLUSIONS: DRB1*04 alleles may partially account for the genetic predisposition to schizophrenia. The association reported here may be explained by genetic linkage or by an autoimmune pathophysiology for a proportion of schizophrenia cases. Alternatively, it may be that maternal B lymphocytes that do not express the DR4 antigen encoded by DRB1*04 respond to influenza virus by producing antibodies that perturb neurodevelopment, thus underpinning a proportion of schizophrenia cases.


Subject(s)
Schizophrenia/genetics , Chromosomes, Human, Pair 6 , HLA-DQ Antigens , HLA-DQ beta-Chains , HLA-DR Antigens , HLA-DRB1 Chains , Humans
8.
N Engl J Med ; 334(13): 815-20, 1996 Mar 28.
Article in English | MEDLINE | ID: mdl-8596547

ABSTRACT

BACKGROUND: End-stage cirrhosis related to hepatitic C virus (HCV) is a common reason for liver transplantation, although viremia ia known to persist in most cases. We investigated the impact of persistent HCV infection after liver transplantation on patient and graft survival and the effects of the HCV genotype and the degree of HLA matching between donor and recipient on the severity of recurrent hepatitis. METHODS: A group of 149 patients with HCV infection who received liver transplants between January 1982 and April 1994 were followed for a median of 36 months; 623 patients without HCV infection who underwent liver transplantation for end-stage chronic liver disease were used as a control group. A total of 528 liver-biopsy specimens from the HCV-infected recipients were reviewed, including 82 obtained one year after transplantation as scheduled and 39 obtained at five years as scheduled. In addition, biopsy specimens were obtained from 91 of the HCV-negative patients five years after transplantation. RESULTS: Cumulative survival rates for the 149 patients with HCV infection were 79 percent after one year, 74 percent after three years, and 70 percent after five years, as compared with rates of 75 percent, 71 percent, and 69 percent, respectively, in the HCV-negative transplant recipients (P=0.12). Of the 130 patients with hepatitis C infection who survived more than 6 months after transplantation, 15 (12 percent) had no evidence of chronic hepatitis on their most recent liver biopsy (median followup, 20 months), 70 (54 percent) had mild chronic hepatitis (median, 35 months), 35 (27 percent) had moderate chronic hepatitis (median, 35 months), and 10 (8 percent) had cirrhosis (median, 51 months). Graft loss occurred after a median of 303 days in 27 of the 149 patients, including 5 with HCV-related cirrhosis and 3 with HCV-related cholestatic hepatitis. Infection with HCV genotype 1b was associated with more severe graft injury, whereas the primary immunosuppressive regimen used and the extent of HLA mismatching between donors and recipients had no significant effect on this variable. CONCLUSIONS: After liver transplantation for HCV-related cirrhosis, persistent HCV infection can cause severe graft damage, and such damage is more frequent in patients infected with HCV genotype 1b than with other genotypes. After five years, the rates of graft and overall survival are similar between patients with and those without HCV infection.


Subject(s)
Hepatitis C/surgery , Liver Cirrhosis/surgery , Liver Transplantation , Adult , Aged , Biopsy , Chronic Disease , Female , Follow-Up Studies , Genotype , Graft Survival/immunology , Hepacivirus/genetics , Hepatitis C/complications , Histocompatibility Testing , Humans , Liver/pathology , Liver Cirrhosis/etiology , Liver Transplantation/immunology , Liver Transplantation/mortality , Male , Middle Aged , Survival Rate , Treatment Outcome
9.
Transplantation ; 60(9): 1016-23, 1995 Nov 15.
Article in English | MEDLINE | ID: mdl-7491675

ABSTRACT

Early studies in liver transplantation suggested that there was no association between graft outcome or rejection and the presence of alloantibodies before transplantation. More recent reports have suggested lower graft survival rates and a higher incidence of chronic rejection in patients with IgG warm-T crossmatches. In the present study, panel reactive antibody, direct crossmatch testing, and flow cytometry were used to detect preformed antibodies in sera from 158 consecutive adult recipients of first hepatic grafts. The relationship between preformed antidonor antibodies and liver allograft survival and rejection was determined. Twenty-six (17%) patients were panel reactive antibody (PRA)-positive before transplantation, 22 (15%) had positive donor-specific crossmatches, and 14 (9%) were positive by IgG-specific flow cytometry. Cumulative survival distribution and multivariate analysis failed to reveal any significant associations between overall graft survival and antibody status. Graft survival in patients with PRA-positive sera was 81% compared with 77% for those with PRA-negative sera, 68% for those with positive donor-specific crossmatches compared with 80% for those who were donor-specific crossmatch negative, and 79% for those who were antibody positive by flow cytometric analysis compared with 78% for those who were antibody negative. Subgroup analysis also failed to reveal any significant associations. In addition, Cox proportional hazards regression analysis failed to reveal a relationship between acute or chronic graft rejection with the presence or absence of preformed antibodies, irrespective of immunoglobulin class, cell type (T or non-T), specificity, or technique used for antibody detection. In conclusion, there appears to be no association between either donor-specific or "third-party" alloreactive IgG or IgM antibodies and liver transplant survival or rejection. These data do not indicate a need for prospective crossmatching of liver transplant recipients.


Subject(s)
Graft Rejection/immunology , Graft Survival/immunology , Histocompatibility Testing , Immunoglobulin G/immunology , Liver Transplantation/immunology , Adolescent , Adult , Aged , Antibody Specificity , Female , Flow Cytometry , Humans , Immunoglobulin G/blood , Immunoglobulin M/blood , Lymphocyte Depletion , Male , Middle Aged , Prognosis , Spleen/immunology , T-Lymphocytes/immunology
10.
Hepatology ; 21(4): 959-62, 1995 Apr.
Article in English | MEDLINE | ID: mdl-7705806

ABSTRACT

In recent years there has been an increasing interest in the link between susceptibility to autoimmune liver disease and genes of the HLA system, although the role of the DPB1 locus in British patients has only been investigated in autoimmune hepatitis. The aim of the current study was to determine the distribution of DPB1 alleles in a large series of British patients with the two other autoimmune liver diseases, primary biliary cirrhosis and primary sclerosing cholangitis, and compare the allele frequencies obtained with those of a geographically matched control group. Polymerase chain reaction sequence-specific oligonucleotide probing was used to assign 18 DPB1 alleles in 82 patients with primary biliary cirrhosis (PBC), 71 patients with primary sclerosing cholangitis (PSC), and 103 controls. The frequencies of the DPB1 alleles were not significantly different comparing patients and controls. However, two important observations were made. Firstly, in primary sclerosing cholangitis, the previously reported association with the haplotype A1-B8-DR3-DQ2 does not extend to the DPB1 locus, suggesting that the genetic determinants of susceptibility for this disease lie closer to the DRB loci. Secondly, in primary biliary cirrhosis there is evidence that the reported association with DR8-DQB1*0402 includes the DPB1*0301 allele. The weak HLA association reported here is in contrast with recent data from Japan, where susceptibility is strongly linked to a particular amino acid residue encoded by the DPB1*0501 allele. These data clearly demonstrate that the alleles of the DPB1 locus are not associated with susceptibility to or protection from either primary biliary cirrhosis or primary sclerosing cholangitis in British patients.


Subject(s)
Cholangitis, Sclerosing/genetics , HLA-DP Antigens/genetics , Liver Cirrhosis, Biliary/genetics , Polymorphism, Genetic , Adult , Aged , Alleles , Base Sequence , Cholangitis, Sclerosing/immunology , Female , HLA-DP beta-Chains , HLA-DQ Antigens/genetics , HLA-DR Antigens/genetics , Haplotypes , Humans , Liver Cirrhosis, Biliary/immunology , Male , Middle Aged , Molecular Sequence Data
11.
Gastroenterology ; 106(5): 1321-5, 1994 May.
Article in English | MEDLINE | ID: mdl-7909781

ABSTRACT

BACKGROUND/AIMS: Susceptibility to autoimmune hepatitis is associated with HLA A1-B8-DR3 and DR4. T-Cell antigen receptors (TCR) are candidates for genetic susceptibility to autoimmune diseases because they recognize peptide antigens in the context of HLA molecules. The aim of this study was to investigate the possible role of TCR germline polymorphisms in susceptibility to autoimmune hepatitis. METHODS: TCR constant beta (C beta) region polymorphisms were investigated using restriction fragment length polymorphism analysis in 60 unrelated northern European White patients with autoimmune hepatitis and 190 racially and geographically matched healthy controls. RESULTS: A significant increase in the frequency of homozygous status for the 10-kilobase/Bgl II of the TCR C beta was found in the patients compared with controls (42% vs. 21%; corrected P value [Pc] < 0.0075; relative risk [RR] = 2.8). This difference was more pronounced in patients without HLA-DR3 and DR4 (50% vs. 14%; Pc < 0.015; RR = 6.1). Furthermore, heterozygosity for TCR C beta was significantly decreased in early-onset patients presenting with HLA-DR3 before 30 years of age (12% vs. 48%; Pc < 0.03; RR = 0.16). CONCLUSIONS: The present findings provide evidence that genetic susceptibility to AIH may be determined by both the TCR C beta genes and HLA genes and that the genotype of the TCR C beta may be one of the factors in influencing the age at onset of disease.


Subject(s)
Autoimmune Diseases/genetics , Genetic Predisposition to Disease , Hepatitis/genetics , Polymorphism, Genetic , Receptors, Antigen, T-Cell, alpha-beta/genetics , Adolescent , Adult , Age Factors , Aged , Aged, 80 and over , Autoimmune Diseases/immunology , Child , Child, Preschool , DNA/genetics , Female , Genotype , HLA-A1 Antigen/genetics , HLA-B8 Antigen/genetics , HLA-DR3 Antigen/genetics , HLA-DR4 Antigen/genetics , Hepatitis/immunology , Homozygote , Humans , Male , Middle Aged , Polymorphism, Restriction Fragment Length , Severity of Illness Index
12.
Hepatology ; 19(3): 609-15, 1994 Mar.
Article in English | MEDLINE | ID: mdl-8119685

ABSTRACT

Susceptibility to autoimmune hepatitis in white patients is associated with the human leukocyte antigen class II antigens DR3 and DR4. To analyze the molecular basis of these associations, we used oligonucleotide probes to determine the DRB, DQA and DQB hypervariable nucleotide sequences in 119 patients with autoimmune hepatitis and 177 matched controls. DRB3*0101, which encodes DR52a, predisposed patients most strongly to the disease. It was present in 58% of patients and 25% of controls (corrected P < 0.000005), whereas DQA1*0101 and 0102 conferred protection in males only. The DR4 subtype, DRB1*0401, was raised in the DRB3*0101-negative patients; 81% possessed either DRB3*0101 or DRB1*0401, compared with 42% of controls (corrected P < 0.0000001). These alleles encode the amino acid sequence Leu-Leu-Glu-Gln-Lys-Arg at positions 67 to 72 of the DR beta polypeptide, which was present in 94% of patients and 64% of controls (corrected P < 0.000001) and in all patients who tested positive for autoantibodies to the hepatic asialoglycoprotein receptor. The patients with DRB1*0401 had less severe disease, relapsed less frequently and were first seen significantly later in life than those patients with DRB3*0101; and whereas a single copy of DRB1*0401 predisposed to autoimmune hepatitis, DRB3*0101-associated susceptibility had a dose-related effect. These data provide evidence that specific residues in the DR beta polypeptides predispose to autoimmune hepatitis in white patients and genes linked to DRB3*0101 and DRB1*0401 may determine two clinically distinct disease patterns.


Subject(s)
Alleles , Autoimmune Diseases/genetics , Genes, MHC Class II/genetics , Genetic Variation , Hepatitis/genetics , Histocompatibility Antigens Class II/genetics , Adolescent , Adult , Aged , Aged, 80 and over , Amino Acid Sequence , Autoimmune Diseases/immunology , Child , Child, Preschool , Female , Hepatitis/immunology , Humans , Male , Middle Aged , Molecular Conformation , Molecular Sequence Data
13.
Autoimmunity ; 18(4): 243-9, 1994.
Article in English | MEDLINE | ID: mdl-7858109

ABSTRACT

Susceptibility to autoimmune hepatitis is associated with the HLA-DR3 and DR4 haplotypes, but which genes are directly involved in the pathogenesis, has not been established. Low levels of complement component C4 and elevated frequencies of C4 null allotypes have been described in patients, suggesting that the C4 genes, which are closely linked with the HLA loci, may play a role. We therefore examined restriction fragment length polymorphisms in the C4 and 21-hydroxylase genes, and determined HLA-A and B phenotypes, and HLA-DR, DQ and DP genotypes in a large series of Caucasoid patients with autoimmune hepatitis and matched controls. A DNA deletion of the C4A gene and the 21-hydroxylase A pseudogene was found to be present in 50% of patients compared to 23% of controls (Pc < 0.005, relative risk = 3.3). This increase, however, appears to be due to linkage disequilibrium with HLA-DR52a which was most strongly associated with the disease. Complete C4A deficiency, determined by homozygosity for the deletion increased the risk to 18.1 (16% versus 1%, Pc < 0.005), suggesting an additional role for C4 in disease susceptibility. C4 deletions were associated with an increased mortality and tendency to relapse whilst on treatment but did not correlate with age of onset of disease. Our data suggest that MHC-encoded susceptibility to autoimmune hepatitis is polygenic, involving the HLA-DR genes plus other loci, and C4 deficiency may be a marker of disease susceptibility and/or severity.


Subject(s)
Autoimmune Diseases/genetics , Complement C4/genetics , Hepatitis/genetics , Polymorphism, Restriction Fragment Length , Steroid 21-Hydroxylase/genetics , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Disease Susceptibility , Female , Gene Deletion , Genetic Heterogeneity , HLA Antigens/genetics , Haplotypes/genetics , Hepatitis/immunology , Humans , Male , Middle Aged
14.
Hepatology ; 18(6): 1334-7, 1993 Dec.
Article in English | MEDLINE | ID: mdl-8244257

ABSTRACT

Genetic susceptibility to autoimmune hepatitis is associated with the human leukocyte antigen haplotype A1-B8-DR3 and DR4. To date, only one study in Japan has considered the human leukocyte antigen DP locus in this disease, and no studies have been reported in whites. In this study we used a series of sequence-specific oligonucleotide probes to determine human leukocyte antigen DPB1 genotypes in 101 unrelated white northern European patients and 105 racially and geographically matched controls. The aims of the study were twofold: first, to determine the degree of DPB-encoded susceptibility to autoimmune hepatitis, and, second, to establish whether susceptibility can be extended to include human leukocyte antigen DPB. None of 17 DPB1 alleles was significantly associated with the susceptibility to autoimmune hepatitis. Although one particular seven-locus haplotype A1-B8-DRB3*0101-DRB1*0301-DQA1*0501-DQB1*0201-++ +DPB1*0401 was significantly associated with the disease (27% vs. 7%, relative risk = 5.14, p < 0.0005), the association with this haplotype was weaker than that for the six-locus haplotype excluding DPB (40% vs. 11%, RR = 5.52, p < 0.0005). When the patients first seen at ages younger than 16 yr (pediatric patients) were considered separately, the greatest relative risk was for the seven-locus haplotype (41% vs. 7%; relative risk = 9.60, p < 0.0005). The results of this study further confirm that major histocompatibility complex-encoded susceptibility to autoimmune hepatitis is located at or close to the human leukocyte antigen DR locus; however, the A1-B8-DR3-DQ2-DPB1*0401 extended haplotype may be important in determining the age of onset and severity of disease.


Subject(s)
Autoimmune Diseases/genetics , Autoimmune Diseases/immunology , HLA Antigens/genetics , Haplotypes , Hepatitis/genetics , Hepatitis/immunology , Adolescent , Adult , Age Factors , Aged , Aged, 80 and over , Alleles , Autoimmune Diseases/ethnology , Child , Child, Preschool , Female , Gene Frequency , Genetic Predisposition to Disease , HLA-A1 Antigen/genetics , HLA-B8 Antigen/genetics , HLA-DP Antigens/genetics , HLA-DP beta-Chains , HLA-DQ Antigens/genetics , HLA-DR3 Antigen/genetics , Hepatitis/ethnology , Humans , Male , Middle Aged , Polymorphism, Genetic , White People
16.
J Immunol ; 149(4): 1191-8, 1992 Aug 15.
Article in English | MEDLINE | ID: mdl-1500712

ABSTRACT

Op18 is a highly conserved major cytosolic phosphoprotein that has been implicated in signal transduction in a wide variety of cell types. Freshly isolated peripheral blood lymphocytes (PBL) constitutively express low levels of mostly unphosphorylated Op18. After mitogenic stimulation of PBL, Op18 synthesis is induced at a time when cells are entering S-phase. In this study, we have examined the phosphorylation of Op18 in freshly isolated PBL after activation of the T cell receptor by OKT3. Quantitative analysis of Op18 phosphorylation was undertaken by metabolic labeling with 32Pi and PhosphorImager analysis of two-dimensional gels. After 10 or 15 min of activation by OKT3, one of the three major phosphorylated forms of Op18, designated Op18c, increased approximately 10-fold, which represented a most pronounced change among a large number of phosphoproteins analyzed. In time course experiments, increased Op18 phosphorylation to yield Op18c was observed as early as 2 min. Continued OKT3-induced activation for 20 to 72 h resulted in a further increase in phosphorylated Op18 forms, which paralleled new Op18 synthesis and occurred at a time when cells were entering S-phase, as determined by [3H]-thymidine incorporation. Inhibitors of lymphoid proliferation, cyclosporin A and RPM, had no effect on early (less than 15 min) phosphorylation. Addition of calphostin C, a specific inhibitor of protein kinase C, 1 min prior to stimulation of resting T cells with OKT3 completely inhibited further phosphorylation of Op18. Incubation of PBL with calphostin C for 75 min decreased constitutive levels of phosphorylated Op18. In contrast, inhibition of cyclic nucleotide-dependent protein kinases with HA1004 had no effect on Op18 phosphorylation. Activation of cAMP-dependent protein kinase with Forskolin or 8Br-cAMP did not increase Op18 phosphorylation. Our results suggest that Op18 phosphorylation is mediated by protein kinase C activation as an early event in T cell activation through the T cell receptor.


Subject(s)
Lymphocyte Activation , Microtubule Proteins , Phosphoproteins/metabolism , Receptors, Antigen, T-Cell/metabolism , Cells, Cultured , Electrophoresis, Gel, Two-Dimensional , Humans , In Vitro Techniques , Muromonab-CD3/immunology , Phosphorylation , Protein Kinase C/antagonists & inhibitors , Protein Kinases/metabolism , Signal Transduction , Stathmin , Time Factors
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