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C Johanet

Publications and source records attributed to C Johanet.

At least 55 records · Page 3Linked to original sources
PubMed1993

[Characterization of anti-mitochondrial antibodies type 2 (anti-M2): comparison of two techniques, western blotting and indirect immunofluorescence].

About 94% of patients with typical features of primary biliary cirrhosis (PBC) have been shown to be anti-M2 positive. Today the relevance of anti-M2 antibodies as a diagnostic marker of PBC is well established. The usual method of detection is by indirect immunofluorescence with cryostat sections of rat organs. In our laboratory we have developed a second identification technique for these antibodies: Western-blotting. To compare immunofluorescence and immunoblotting results, we selected sera from 252 patients: 142 sera from patients with documented PBC, 50 from patients with another hepatic disease, 10 from patients with haematological lupus and 50 from healthy blood donors. We characterized antimitochondrial antibody M2 by the presence of one or more of five antigenic determinants: 65-70 kDa (a), 52-54 kDa (b), 44 kDa (c), 23-26 kDa (d) and 16-20 kDa (e). This technique is especially useful as a backup method intention for identifying a very slight or atypical fluorescence pattern.

Autoantibodies↗
PubMed1992

Characterization of the liver cytosol antigen type 1 reacting with autoantibodies in chronic active hepatitis.

An autoantibody to liver cytosol was previously described in childhood autoimmune chronic active hepatitis type 2. The antigen, liver cytosol antigen type 1, was for the first time partially purified using gel filtration and ion exchange chromatography, and it was characterized using immunodiffusion, immunoblot and sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of the immunoprecipitate. Immunoblot detected a unique antigenic peptide at 62 kD from human cytosol and at 58 kD from rat cytosol. The same peptides were also detected when immunoprecipitates of liver cytosol antigen type 1 and autoantibodies to liver cytosol antigen were submitted to sodium dodecyl sulfate-polyacrylamide gel electrophoresis. A polymeric structure, probably a tetramer, is suggested for native liver cytosol antigen type 1 because in gel filtration chromatography liver cytosol antigen type 1 was eluted as a protein of a molecular weight between 240 and 290 kD when human liver cytosol was fractionated and between 220 and 270 kD from rat liver cytosol. Liver cytosol antigen type 1 is probably poor in carbohydrates because it was not stained by periodic acid-Schiff stain. The autoantibodies to liver cytosol were frequently found in association with antiliver kidney microsomal autoantibodies type 1, which are directed against the cytochrome P-450 of the IID6 subfamily. Antiliver kidney microsomal autoantibodies type 1 but not antiliver cytosol autoantibodies were found in association with antibodies to hepatitis C virus. Autoantibodies to liver cytosol antigen type 1 seem to be a more specific marker for autoimmune hepatitis type 2 than antiliver kidney microsomal antibodies type 1 autoantibodies.

Animals↗
PubMed1992

Long-term follow-up study of 164 patients with definite systemic sclerosis: classification considerations.

To evaluate the usefulness of recently proposed schemes of classification for systemic sclerosis an extensive cross-sectional study of a series of 164 consecutive patients with long-term systemic sclerosis was undertaken. There were 47 cases of proximal sclerosis, 93 of distal sclerosis and 24 of complete CREST syndrome. The study included clinical, visceral, immunological and follow-up data. In addition, a quantitative clinical score was calculated for each patient, thus providing indications for prognosis. Data were expressed according to three conventional systems of classification: The ARA system, the diffuse versus limited systemic sclerosis system and the early cutaneous involvement system. The most reliable indications of severe outcome were: proximal sclerosis, trunk skin involvement, presence of anti Scl 70 autoantibody, pulmonary and/or heart involvement and age. Diagnosis and prognosis were not generated by the same items. Prognosis indicators proved more accurate for groups than for individuals. Mortality was 1 death per 149 patient X years of follow-up from diagnosis. We conclude that the ARA criteria for classification should be recognized as a standard, but patients with complete CREST syndrome should be included in the distal group. Other systems of classification, principally 2-way versus 3-way criteria, allow different subsets of patients that correlate with prognosis and the severity of the disease, and could be used for therapeutic purposes.

Adolescent↗
PubMed1991

[Evaluation of a radioimmunologic technique for the detection of anti-native DNA antibodies].

The anti-native DNA antibodies were measured by a radioimmunoassay (RIA) type Farr assay in the sera from 648 patients: 108 with active or inactive systemic lupus erythematosus (SLE), 181 with clinical symptoms of another connective tissue disease, 171 with liver diseases, 29 with different pathology and 159 normal sera were obtained from a blood bank. The anti-DNA kit has been calibrated against the first international units/ml. This assay has proved to be sensitive and specific, and appears to be reliable for the diagnosis and follow-up of SLE patients. The authors propose a new reference cut-off level higher than producer's one.

Antibodies, Antinuclear↗
PubMed1990

Detection of autoantibodies to Sm antigen in systemic lupus erythematosus by immunodiffusion, ELISA and immunoblotting: variability of incidence related to assays and ethnic origin of patients.

Autoantibodies to small nuclear ribonucleoproteins (snRNP) were studied using the techniques of immunodiffusion, ELISA, and immunoblotting in the sera of 150 patients with systemic lupus erythematosus (SLE), and of 29 patients with mixed connective tissue disease; 900 control patients and 100 normal blood donors were examined simultaneously. The incidence of anti-Sm antibodies in French SLE patients was low compared with the occurrence observed in similar studies in USA (even when highly sensitive assays were used) but was of the same magnitude as European results. Frequency of anti-Sm antibodies in SLE patients varied moderately when detected by immunodiffusion (12%), or by immunoblotting (17%), however, it seems that the ethnic and/or genetic background of patients induces more significant differences. SLE patients from the French West Indies had anti-Sm antibodies in 39% of cases when detected by immunodiffusion and in 50% when immunoblotting was used. In these patients the incidence of the antibodies was five times more frequent than that of mainland French patients. Immunization against snRNP does not seem to be a common feature of all SLE patients.

Antibody Specificity↗
PubMed1990

[Anti-Scl-70 antibodies in systemic scleroderma].

We looked for anti-Scl-70 and anti-centromere antibodies in 109 patients (26 men and 83 women). Mean age was 43 +/- 15 years. Forty patients had systemic sclerosis according to ARA criteria. The extension of cutaneous involvement was defined by using Barnett and Coventry criteria: 12 patients were type I (sclerodactyly), 20 type II (acrosclerosis) and 8 type III (diffuse scleroderma). Among the 12 patients with type I, there were 8 cases of CREST syndrome defined as follows: presence of sclerodactyly, Raynaud's phenomenon and 2 of the 3 following criteria: oesophageal dysmotility, calcinosis, telangiectasia. Other organ involvement was recorded. Control patients had idiopathic Raynaud's phenomenon (n = 22), other connective tissue diseases (n = 20), and miscellaneous diseases (n = 28). Ninety-nine patients were prospectively included in this study. Patients' sera were stored at -20 degrees C. Ten previously stored sera obtained from patients with systemic sclerosis were also analyzed. Immunological tests were performed simultaneously and with no information on the diagnosis. When antinuclear antibodies were detected by indirect immunofluorescence, double immunodiffusion and immunoblotting were performed. Anti-Scl-70 antibodies were detected in systemic sclerosis only: 1 of 12 type I, 11 of 20 type II and 4 of 8 type III. One serum negative by immunodiffusion was positive using immunoblotting. We found that the specificity of anti-Scl-70 antibodies for systemic sclerosis was 100 p. 100 and their sensitivity 40 p. 100. There was a correlation between the presence of anti-Scl-70 antibodies and the presence of antinuclear antibodies (p less than 0.05) and the extent of cutaneous involvement (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

Serological arguments for classifying Raynaud's phenomenon as idiopathic.

Twenty-five patients with idiopathic Raynaud's phenomenon were followed prospectively for a mean period of 48 months. Clinical and laboratory assessments were performed on admission and on followup. The sera were analyzed for the presence of autoantibodies (antinuclear, antiskeleton and antiorganelle antibodies). Sixteen patients were antinuclear antibody positive and 2 anticentromere antibody positive. Eight patients produced antivimentin, 5 antimitochondrial, 4 anti-Golgi complex, and 3 anticentriol antibodies. Eleven patients produced antidesmosome antibodies. Only one patient (anti-RNP and antidesmosome antibody positive) developed a systemic disease (mixed connective tissue disease) during followup. The initial screening of sera may help to classify Raynaud's phenomenon as idiopathic more accurately.

Adolescent↗
PubMed1989

[Anti-Scl-70 and anti-centromere autoantibodies. Biological markers of 2 forms of systemic scleroderma].

The diagnostic and prognostic value of anti-Scl-70 autoantibodies in systemic scleroderma and other connective tissue diseases was investigated. A clinical and immunological study consisting of a search for anti-Scl-70 autoantibodies by immunodiffusion and immunoblot and a search for anti-centromere autoantibodies and antinuclear factors by indirect immunofluorescence was conducted in 57 cases of systemic scleroderma, 45 cases of CREST syndrome, 41 patients with suspected systemic scleroderma but who did not respond to the American rheumatism association (ARA) criteria, 35 cases of systemic lupus erythematosus, 8 cases of polymyositis, 40 cases of Raynaud's phenomenon and 48 controls. Anti-Scl-70 autoantibodies were found by immunodiffusion in 40 and by immunoblot in 45 cases of scleroderma with lesions proximal to the metacarpo-phalangeal joint (a major ARA criterion) and in 3 patients with suspected scleroderma but only one minor criterion: sclerodactyly. In systemic scleroderma with proximal lesions, the anti-Scl-70 autoantibody has a sensitivity of 0.85 and a specificity of 0.99. Anti-centromere autoantibodies were present in 39 cases of complete or incomplete CREST syndrome, 3 cases of Raynaud's phenomenon probably evolving towards a connective tissue disease and 1 case of systemic scleroderma with proximal lesions. The anti-Scl-70 and anti-centromere autoantibodies seem unable to coexist in the same patient and appear to be markers of two forms of scleroderma with different courses and prognoses. The Scl-70 antigen, which is the target of the anti-Scl-70 antibody, has been identified as topoisomerase 1, and a functional abnormality of this enzyme might contribute to some of the chromosomal abnormalities described in scleroderma.

Autoantibodies↗
PubMed1989

Characteristics of clometacin-induced hepatitis with special reference to the presence of anti-actin cable antibodies.

The clinical, biochemical, histopathological and immunological features of 30 cases of clometacin-induced hepatitis are described. The age range of the patients was 32-84 years with a notable female predominance of 29:1. The hepatitis was highly cytolytic with high values of transaminases but with little or no cholestasis. Gammaglobulins were higher than 18 g/l in 73% of the cases. 25 liver biopsies were performed and showed acute hepatitis with a predominant centrilobular necrosis in 17; chronic aggressive hepatitis was noted in 8 cases but 1 showed concomitant cirrhotic changes. Anti-tissue antibodies were looked for in all cases. Anti-smooth muscle antibodies of anti-actin cable type (titre 1/80 to 1/2, 560) were detected in 19 cases, anti-nucleus antibodies in 16 cases which were associated to the former in 14 cases. The above findings show that clometacin produces a hepatitis syndrome quite akin to autoimmune chronic active hepatitis (lupoid hepatitis) and to the hepatopathy induced by oxyphenisatin.

Actins↗
PubMed1989

[Idiopathic portal hypertension associated with connective tissue disease similar to systemic lupus erythematosus].

A case of idiopathic portal hypertension associated with connective disease resembling systemic lupus erythematosus is described. The patient was a 50-year-old woman with splenomegaly, ascites, esophageal varices, and pancytopenia, but without extrahepatic portal obstruction or cirrhosis of the liver. Electron microscopy of the liver showed perisinusoidal fibrosis. High titers of autoantibodies against proliferating cell nuclear antigen (PCNA) were found in the sera as well as in ascites; anti-DNA antibodies appeared after anti-PCNA antibodies and remained thereafter at a moderate titer. The possibility of an immunological process in the pathogenesis of idiopathic portal hypertension is discussed.

Antibodies, Antinuclear↗
PubMed1983

[Immunoallergic complication induced by rifampicin with disseminated intravascular coagulation].

In a 48-years old woman, intermittent rifampicin treatment induced an immunoallergic reaction with digestive disorders, haemolysis, acute renal failure and prolonged prothrombin time. The reintroduction of rifampicin, 17 days later, resulted in a similar, though more severe, reaction associated with diffuse haemorrhages from disseminated intravascular coagulation, this association being exceptional. The responsibility of rifampicin was demonstrated by the chronological relationship between clinical symptoms and administration of the drug, and by the presence in the patient's serum of anti-rifampicin antibodies. The antigen-antibody reaction with complement activation and haemolysis probably explains the disseminated intravascular coagulation.

Acute Kidney Injury↗
PubMedDate not supplied

Antibody to liver cytosol (anti-LC1) in patients with autoimmune chronic active hepatitis type 2.

A new autoantibody was detected by immunoprecipitation in the serum of 21 patients with chronic active hepatitis. The antibody reacted against a soluble cytosolic antigen in liver. The antibody was organ specific but not species specific and was therefore called anti-liver cytosol antibody Type 1 (anti-LC1). In seven of 21 cases, no other autoantibody was found; the remaining 14 cases had anti-liver/kidney microsome antibody Type 1 (anti-LKM1). With indirect immunofluorescence, a distinctive staining pattern was observed with the seven sera with anti-LC1 and without anti-LKM1. The antibody stained the cytoplasm of hepatocytes from four different animal species and spared the cellular layer around the central veins of mouse and rat liver that we have called juxtavenous hepatocytes. The immunofluorescence pattern disappeared after absorption of sera by a liver cytosol fraction. The 14 sera with both antibodies displayed anti-LC1 immunofluorescent pattern after absorption of anti-LKM1 by the liver microsomal fraction. The anti-LC1 was found in the serum only in patients with chronic active hepatitis of unknown cause. Anti-LC1 antibody was not found in sera from 100 patients with chronic active hepatitis associated with anti-actin antibody classic chronic active hepatitis Type 1, 100 patients with primary biliary cirrhosis, 157 patients with drug-induced hepatitis and a large number of patients with liver and nonliver diseases. This new antibody was considered a second marker of chronic active hepatitis associated with anti-LKM1 (anti-LKM1 chronic active hepatitis) or autoimmune chronic active hepatitis Type 2.

Antibodies↗
PubMedDate not supplied

[The diagnostic value of anti-DNA antibodies depends on the technic used for their detection].

Three anti-native DNA antibody detecting assays were compared using sera from 948 patients with clinical symptoms of connective tissue disease and 55 definite systemic lupus erythematosus patients. The Farr assay was more effective than the two other assays in the diagnosis of lupus. Anti-DNA antibody detection by ELISA was as sensitive as the Farr assay; in contrast indirect immunofluorescence on Crithidia luciliae had a significantly lower sensitivity, detecting less than one out of two cases of lupus detected. Particularly ELISA but also indirect immunofluorescence may give positive results in the absence of lupus, so that results obtained by each of these assays must be confirmed by the Farr assay if they are used in the diagnosis of lupus. The significance of antibodies detected by one assay but not by the others is discussed.

Antibodies, Antinuclear↗
PubMedDate not supplied

[Analytic study of dot blotting for the detection of anti-Jo-1, anti-M2, anti-ribosomes and anti-LKM].

The Cyto-Dot 4 HM043 kit commercialised by BMD, has replaced the Cyto-Dot HM010 kit that allowed three auto-antibodies detection (anti-Jo-1, anti-M2 and anti-ribosomal protein). Detection of anti-LKM1 auto-antibody was added. These four auto-antibodies have in common only the intracytoplasmic localisation of their respective antigen. The aim of our study was to evaluate this new kit using 104 sera and to compare our results with reference techniques (indirect immunofluorescence IF for anti-M2, anti-ribosomal protein and anti-LKM1, double immunodiffusion ID for anti-Jo-1 and anti-LKM1, western blotting WB for anti-M2) and with Cyto-Dot HM010. The one hundred and four sera were divided into five groups: Group I (n = 12) with anti-Jo-1 detected by ID; Group II (n = 28) with 26 anti-M2 positive by IF and WB, 2 anti-M2 positive only by WB; Group III (n = 10) with anti-ribosomal protein detected by IF 5 of which precipitated by ID; Group IV (n = 32) with anti-LKM1 by IF and ID divided into 18 AIH2 and 14 HCV; Group V (n = 22) consisting of 14 healthy individuals and 8 patients with hypergammaglobulinemia. Results of this study are similar to those of Cyto-Dot HM010 for the three auto-antibodies already in use. Cyto-Dot 4 is a very good anti-LKM1 confirmation method as it is ID.

Arthritis↗
PubMedDate not supplied

[Antinuclear antibodies in primary biliary cirrhosis].

Antinuclear and antinuclear membrane autoantibodies are detected by indirect immunofluorescence in sera of 62 p. 100 of primary biliary cirrhosis patients; when anti-SS-A (Ro) and anti-SS-B (La) autoantibodies were included, 70 percent of patients had at least one type of antinuclear antibody. Of 89 patients with primary biliary cirrhosis, 30 had either Raynaud's phenomenon, Sjögren's syndrome or the CREST syndrome. Some antinuclear antibodies, anticentromere and speckled S1 type, seem to correlate with the associated connective tissue disease. Antibodies showing the S3 pattern (multiple nuclear dots) and antibodies to nuclear membrane may be present independently of an association with connective tissue disease. In the classical technical conditions used to detect anti-tissue and anti-mitochondrial autoantibodies on tissue sections, antinuclear antibodies like anti-centromere or S3 may not be detected and/or identified. Primary biliary cirrhosis patient sera for antinuclear antibodies determination must be screened by at least two assays: indirect immunofluorescence on a human cell line, like HEp-2, and immunodiffusion. The last assay must be performed even if antinuclear antibodies are undetected by immunofluorescence.

Antibodies, Antinuclear↗
PubMedDate not supplied

[Hepatic function and significance of the increase in serum concentrations of IgA in alcoholic cirrhosis].

Elevated serum gammaglobulin concentrations are frequently observed in patients with liver cirrhosis. Predominant elevation of the IgA is generally considered as suggestive of an alcoholic aetiology. The aim of this study was to define the factors that determine the serum concentration of IgA in alcoholic cirrhosis. Twenty-seven patients with alcoholic cirrhosis were studied. Serum concentrations of IgG, IgA and IgM were measured by immunonephelometry. Hepatocellular function was assessed by the Child-Turcotte score, the prothrombin time and the intrinsic clearance of indocyanine green. The importance of intra-hepatic shunts was estimated according to the intact hepatocyte theory, and the degree of hepatic necrosis by serum levels of transaminases. It was noted that: 1) the IgA concentration correlated significantly with the Child-Turcotte score and with the decrease of the prothrombin time, intrinsic clearance and the functional fraction of hepatic blood flow; 2) there was no such correlation between the serum concentration of IgA and the total hepatic blood flow or transaminase levels; 3) there was no correlation between serum concentration of IgG or IgM and the factors studied. These results suggest that in alcoholic cirrhosis, increase in serum IgA, reflects the degree of impairment of hepatic function and intrahepatic shunting.

Humans↗