0000000000466199
AUTHOR
A. Kyriatsoulis
showing 11 related works from this author
Clonal analysis of liver-infiltrating T cells in patients with LKM-1 antibody-positive autoimmune chronic active hepatitis
1991
SUMMARY Autoantibodies against microsomal antigen of liver and kidney (LKM-1) are diagnostic markers for a subgroup of autoimmune chronic active hepatitis (AI-CAH). Cytochrome P4S0dbl, now classified as cytochrome P450 IID6, is the major antigen of LKM-1 antibodies. Immunohistological studies suggest that hepatic injury in AI-CAH is mediated by liver-infiltrating T cells. In the present study the specificity and function of liver-infiltrating T cells was analysed at the clonal level. Phenotypical characterization of 189 T cell clones isolated from four liver biopsies of LKM-1 antibody-positive patients showed an enrichment of CD4+CD8- T cells. Five CD4+CD8- T cell clones proliferated specif…
Characterisation of a new subgroup of autoimmune chronic active hepatitis by autoantibodies against a soluble liver antigen.
1987
Autoantibodies against a soluble liver antigen (SLA) were detected in 23 patients with HBsAg-negative chronic active hepatitis (CAH) but not in 502 patients with various other hepatic and non-hepatic disorders or 165 healthy blood donors. Anti-SLA-positive serum samples were negative for antinuclear and liver-kidney-microsomal antibodies, markers of two subgroups of autoimmune-type CAH, 6 anti-SLA-positive patients were negative for all autoantibodies sought. Most of the anti-SLA-positive patients were young women (2 men, 21 women; mean age 37 years) with hypergammaglobulinaemia (mean 3.2 g/l, range 1.8-5.3 g/l); 18 of the 23 patients had received immunosuppressive treatment and all respond…
Two different subtypes of antimitochondrial antibodies are associated with primary biliary cirrhosis: identification and characterization by radioimm…
1987
Antimitochondrial antibodies from patients with primary biliary cirrhosis react with different mitochondrial polypeptides as demonstrated by Western blots. The IgG fractions of a patient with primary biliary cirrhosis Stage I reacting exclusively with a pair of polypeptides at 48,000 daltons (p 48) on Western blot and from a patient with Stage III primary biliary cirrhosis reacting exclusively with a single 62,000 dalton polypeptide (p 62) were labeled with 125I; two radio-immunoassays were established detecting antimitochondrial antibodies against p 62 and p 48, respectively. Autologous sera blocked the assay, but the two reference sera did not block each other. Fourteen of 40 patients wit…
Immunochemical characterization of anti-acetylcholine receptor antibodies in primary biliary cirrhosis
1988
Although the presence of anti-mitochondrial antibodies is the main characteristic of primary biliary cirrhosis (PBC), other autoantibodies have been described in this disease. This study employs immunoblot methods to test whether the sera of PBC patients also contain antibodies directed against nicotinic acetylcholine receptors (AChR). We show that the majority of patients' sera indeed react with AChR just as sera of myasthenic patients do. In contrast, however, these anti-AChR antibodies do not lead to significant clinical symptoms of myasthenia. In all cases studied, PBC sera recognized a protein with the molecular weight of the alpha-chain of acetylcholine receptor (40 kDa). In addition,…
Characterization of liver cytokeratin as a major target antigen of anti-SLA antibodies.
1990
Abstract Anti-SLA antibodies characterize a newly defined subgroup of patients with autoimmune chronic active hepatitis. The aim of the present study was the immunochemical characterization of the target antigen(s) of anti-SLA antibodies. Anti-SLA-positive sera were found to contain high titres of anti-cytokeratin antibodies. In immunoblotting analyses with 100 000 × g supernatants of human liver homogenates (S-100) these sera recognized various proteins with a molecular mass of 40–60 kDa. These proteins were also recognized by monoclonal anti-cytokeratin antibodies. Two-dimensional co-electrophoresis and immunoblotting analysis of S-100 and liver cytokeratins showed that anti-SLA antibodie…
Methodology and significance of the detection of liver-kidney-microsomal (lkm) autoantibodies in autoimmune-type chronic active hepatitis
1987
Liver-kidney-microsomal (LKM) autoantibodies are diagnostic markers for a subgroup of HBsAg-negative chronic active hepatitis, presumably owing to autoimmunity. They were originally detected by indirect immunofluorescence and can now be evaluated by radioimmunoassay, enzyme-linked immunosorbent assay, and immunoblotting. In immunoblotting LKM-positive sera react strongly with a 50-kilodalton (KD) polypeptide band of microsomes. In immunoelectron microscopy, LKM-positive sera show a binding with membranes of the endoplasmic reticulum. The LKM antigen was further identified on various isoenzymes of cytochrome P-450. Immunofluorescence is still the method of choice for screening sera routinely…
Untersuchungen zum Verteilungsmuster von Prä S und S-kodierten viralen Hüllproteinen des Hepatitis B Virus (HBV) auf molekularer Ebene im Serum und L…
1989
Die biologische Bedeutung der PraS-kodierten Hepatitis B Virus (HBV) — Hullproteine — insbesondere ihre Regulation innerhalb der Leberzelle — ist noch unklar. Daher war es Ziel unserer Untersuchungen, die PraS- und S-kodierten Hullproteine vergleichend im Serum und im Lebergewebe auf molekularer Ebene zu untersuchen.
Relationship between the target antigen of liver-kidney microsomal (LKM) autoantibodies and rat isoenzymes of cytochrome P-450
1988
Chronic active hepatitis (CAH) is a clinical syndrome of different etiologies. Liver-kidney microsomal (LKM) autoantibodies characterize a subgroup of HBsAg negative CAH, which is considered to be an autoimmune liver disease. By immunoblotting analysis (IB) LKM positive sera have been shown to react strongly with a poly-peptide band at 50 kD. Therefore we investigated various rat microsomal enzymes with a molecular weight around 50 kD as potential candidate target antigens. These included epoxide hydrolase, cytochrome P-450 reductase, and phenobarbital-inducible isoenzymes of cytochrome P-450 (PB1, PB2, PB3a, PB3b). By radioimmunoassay (RIA) and IB LKM positive sera were shown to react with…
In vitro secretion of specific antimitochondrial antibodies in primary biliary cirrhosis
1992
Antimitochondrial antibodies are present in the serum of virtually all patients with primary biliary cirrhosis. They have a well-defined antigen reactivity that is diagnostic for the disease. The role of these autoantibodies in the disease process remains to be defined. In this study we show that antimitochondrial antibodies can be produced in vitro by peripheral blood lymphocytes, that the cells producing antimitochondrial antibodies are present in the peripheral blood in a high frequency and seem to be maximally activated. Stimulation with pokeweed mitogen did not augment the in vitro production of antimitochondrial antibodies in patients nor did it induce the production of these antibodi…
Autoantibodies in experimental autoimmune hepatitis
1992
Experimental autoimmune hepatitis (EAH) can be induced in mice by immunization with syngeneic soluble liver antigens in complete Freund's adjuvant. It has previously been shown that autoreactive T cells play an important role in this animal model of autoimmune hepatitis. We have studied the occurrence of liver autoantibodies in EAH. Characteristic autoantibodies appeared several weeks after disease induction and antibody titres continued to rise when histological and biochemical signs of disease activity had already regressed. Autoantibodies in EAH seemed to recognize autoantigens other than those present in autoimmune chronic active hepatitis patients. We conclude that autoantibodies arise…