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J C Homberg

Publications and source records attributed to J C Homberg.

At least 55 records · Page 3Linked to original sources
PubMed1987

Anti-mitochondrial type 5 antibodies and anti-cardiolipin antibodies in systemic lupus erythematosus and auto-immune diseases.

Twenty sera from patients with systemic lupus erythematosus (SLE) and high titre of IgG anti-cardiolipin antibodies (ACA) were studied in order to evaluate the prevalence of anti-mitochondrial type 5 antibodies (AMA 5). None of these sera were found to be AMA 5 positive but five of 18 were positive for VDRL. Twenty sera from patients with AMA 5 were studied in order to evaluate the prevalence of ACA: only six of 20 were positive for ACA. In contrast to this finding, 15 of the 20 sera positive for AMA 5 were also positive for VDRL (P less than 0.001). The six sera positive for ACA and AMA 5 were absorbed with cardiolipin micelles. This absorption eliminated the ACA activity but not the AMA 5 activity. Despite the clinical similarities between the two groups of patients with AMA 5 or ACA, these data suggest that patients with AMA 5 and patients with ACA belong to two different subsets of SLE or SLE-like syndromes and that AMA 5 antigen is different from cardiolipin.

Autoantibodies↗
PubMed1987

Comparing HEp-2 cell line with rat liver in routine screening test for antinuclear and antinucleolar autoantibodies in autoimmune diseases.

The comparative study of the human tumor cell line HEp-2 and rat liver for the detection of antinuclear and antinucleolar autoantibodies by the indirect immunofluorescence technic in routine screening test demonstrate that, taking titer and staining pattern into account, both substrates are able to separate autoimmune disease (systemic lupus erythematosus, rheumatoid arthritis, scleroderma and primary biliary cirrhosis) patients from healthy subjects. The minimal screening test must include sera diluted 1:20 and 1:80. The capability of the HEp-2 substrate to reveal and to discriminate different speckled nuclear and nucleolar patterns explain its greater performance, notably in detecting anticentromere antibodies highly specific for the CREST syndrome and a speckled nuclear antibody frequently associated with primary biliary cirrhosis, allowing an earlier diagnosis of autoimmune diseases presenting these patterns.

Adult↗
PubMed1986

[4 varieties of islet cell antibodies in 74 insulin-dependent diabetics and their families as a function of the HLA genotype].

The sera of 74 diabetic patients and of their first degree relatives were studied for 4 different types of islet cell antibodies (ICA, CFICA, ICSA, ICACT) and the results were compared according to the HLA genotype. Seventy two percent of the patients' sera were positive for at least one type of auto-antibody. Two types of auto-antibodies were observed: anticytoplasmic antibodies (ICA and CFICA), and surface antibodies (ICSA and ICACT). The different types of antibodies were not associated with any HLA-DR. These antibodies were also present in 15% of the healthy relatives. The fact that they were detected in the sera of siblings sharing no haplotype with the proband, some of them bearing neither DR3 nor DR4 antigens, suggests that non HLA linked genes and/or environmental factors partly control their secretion.

Autoantibodies↗
PubMed1986

Chronic active hepatitis associated with liver-kidney microsomal antibody of an autoimmune type. Two familial cases.

We report the findings in two sisters with active cirrhosis and an anti-liver-kidney microsomal antibody (anti-LKM) of the autoimmune type. This unusual disease is characterized by the presence of high levels of antibodies that react with the smooth and rough endoplasmic reticulum of the liver and other tissues. Our patients had the usual features of chronic hepatitis associated with presence of antibodies: they were young girls, they had anti-LKM antibodies of autoimmune type persisting at a high titer during the whole course of the disease, but with no smooth muscle antibodies; one had a low level of IgA. The occurrence of two cases in the same family has not yet been reported and is probably not coincidental because of the rare occurrence of this disease.

Adolescent↗
PubMed1986

Liver disease associated with anti-liver-kidney microsome antibody in children.

In the past 10 years we have examined 20 children with inflammatory liver disease associated with high serum titers of anti-liver-kidney microsome antibody (anti-LKM). The first hepatic symptoms were progressive fatigue and jaundice, the fortuitous finding of hepatomegaly or splenomegaly with raised transaminase activity, or an acute hepatitis-like illness. At the time of diagnosis, hepatomegaly was present in 18 children, splenomegaly in 16, jaundice in nine, and ascites in two. Serum alanine transferase activities were elevated in all but two, who had already received steroids. Serum total gammaglobulin values were greater than 2.0 gm/dl in 16 children, prothrombin activity less than or equal to 60% in six, and serum titer of anti-LKM between 1:100 and 1:100,000. All children but one had cirrhosis, and histologic signs of aggressivity were present in 14. In 11 children one or more extrahepatic diseases were present, including type 1 diabetes, vitiligo, glomerulonephritis, autoimmune hemolytic anemia, hypoglycemia with hyperinsulinism, autoimmune thyroiditis, chronic mucocutaneous candidiasis with hypoparathyroidism, and multiple cutaneous and visceral telangiectasias. Treatment with prednisone and azathioprine improved the liver condition in 16 of the 18 patients given treatment. In eight of them discontinuation of treatment resulted in rapid relapse; 14 are still receiving treatment and have stable hepatic function with follow-up from 8 months to 6 1/2 years. Only two are free of treatment. Four children died, two in spite of immunosuppressive therapy, one during a relapse, and one of extrahepatic disease. These results indicate that this autoimmune inflammatory liver disease may have onset early in life, with several clinical patterns; is frequently associated with certain types of extrahepatic manifestations of autoimmune origin; and is a potentially fatal disease for which immunosuppressive treatment must be started early.

Adolescent↗
PubMed1985

Anti-liver-kidney microsome antibody recognizes a 50,000 molecular weight protein of the endoplasmic reticulum.

Children with autoimmune chronic active hepatitis may have high titers of antibodies detected by immunofluorescence staining of hepatocytes and tubular cells in rat liver and kidney sections, respectively. These antibodies are directed against antigens contained in microsomal fractions prepared from these two organs. We have found that sera from these patients recognized a 50,000 mol wt protein present in higher concentration in smooth microsome subfractions compared with rough microsome subfractions. This protein is an integral membrane protein and is not glycosylated. It is exposed on the cytoplasmic face of the endoplasmic reticulum and is rather resistant to proteolysis with proteinase K. Since patients with liver disease of different etiology and similar severity of cell lysis do not give rise to liver-kidney microsome antibody (LKMA), lysis of hepatocytes is apparently not a sufficient condition for their development.

Animals↗
PubMed1985

[Value of genetic studies and immunologic markers in diabetes. Prediction of insulin dependence].

A new classification based on physiopathological criteria distinguishes Type I diabetes, observed in patients with stigmata of anti-islet of Langerhans auto-immunity, from Type II diabetes without these autoimmune changes. Type I diabetes is sub-divided into Classes Ia and Ib, Class Ib comprising those cases associated with other auto-immune diseases. Serological analysis of 76 patients with clinical type Ia diabetes and 215 healthy, first degree relatives showed that the distinction between Classes Ia and Ib was not clear-cut and that patients classified clinically Ia were in fact infraclinical Ib subjects. Forty-one per cent of patients with Class Ia diabetes had anti-gastric, anti-adrenal or anti-thyroid antibodies, and 28 p. 100 of their healthy relatives also had the same types of antibodies. Several prospective studies of the families of patients with Type I diabetes have shown that anti-islet of Langerhans antibodies were associated with a high risk of diabetes. Similarly, the presence of these antibodies in patients apparently with Type II diabetes (non-insulin dependent) was associated with an increased risk of developing insulin dependence. These results illustrate the value of immunological investigations in diabetic patients. They may influence the choice of treatment in the future.

Animals↗
PubMed1984

[Autoimmunity induced by drugs. Immunological characteristics and etiopathogenic hypotheses].

Drug-induced autoimmune diseases have two immunological peculiarities. Firstly, some autoantibodies are present, which are virtually never seen in spontaneous human diseases and may be regarded as specific. This applies to antimitochondria antibody type 3 (anti M3) in the lupus-like syndrome caused by Venocuran, to antimitochondria antibody type 6 (anti M6) in iproniazide-induced hepatitis, to anti-insulin antibody found after treatment with methimazole, and to anti liver/kidney microsome antibody type 2 (anti LKM2) associated with hepatitis induced by tielinic acid. Secondly, a search for other autoantibodies shows that the immune disorder is much more limited than in spontaneous autoimmune diseases. Thus, contrary to myasthenia and idiopathic autoimmune haemolytic anaemia, we never found autoantibodies specifically directed against the thyroid, the stomach or the adrenal gland during treatment with D-penicillamine and alpha-methyldopa. Only some hypotheses may account for these peculiarities. Cross-reaction between drug and autoantigen may occur, but the fact that the antigen-antibody reaction is not inhibited by the drug or its metabolites does not support this explanation. Much more attractive is the "T-cell bypass" theory, according to which autoreacting suppressor T-cells are circumvented by helper T-cells stimulated by the drug-modified autoantigen. In this case, the autoimmune reaction would indicate to which body substance the drug is bound, thus making it immunostimulant, and not a structural similarity between the drug and the autoantigen.

Animals↗
PubMed1984

Detection of islet cell antibodies by a microcytotoxicity method.

A microcytotoxicity test for antibodies against islet cells (ICA) is described. Sera from patients with insulin-dependent diabetes, their healthy first degree relatives, and normal controls, genotyped for HLA-A, -B and -DR, were tested by 4 different methods. Cytoplasmic ICA and complement fixing ICA were detected by indirect immunofluorescence with human pancreas sections, and cytotoxic complement dependent ICA and surface ICA were tested against murine beta cell suspensions. Strong correlation was found between cytotoxic and surface antibodies (P less than 10(-7). The technique described is appropriate for use in the screening of large numbers of sera.

Animals↗
PubMed1984

Abnormal anti-single stranded (ss) DNA activity in sera from Plasmodium falciparum infected individuals.

Sera from 32 subjects with Plasmodium falciparum parasitaemia were screened for the presence of antibodies to native-double stranded (ds) DNA and to heat-denaturated-single stranded (ss) DNA by a Farr DNA binding radioimmunoassay. In addition anti-dsDNA antibodies were also studied by indirect immunofluorescence using Crithidia luciliae and rat liver sections as substrates. Immunoglobulin (G, A, M) levels and plasmodial antibodies titres (PA) were concomitantly evaluated. The anti-ssDNA activity was higher in malarious individuals with high IgM levels than in normal or malarious individuals with normal IgM levels. This activity was higher during the acute stage of infection than after recovery. A positive and significant relationship was found between the anti-ssDNA activity and the IgM levels but not with IgG, IgA or PA titres. Speckled antinuclear antibodies (ANA) were also observed in sera from 43.8% of the individuals and the mean ssDNA activity was higher in these ANA positive patients. Conversely anti-dsDNA antibodies could not be detected by any of the tests performed. This preferential production of anti-ssDNA Ab and not anti-dsDNA Ab is additional evidence that the autoantibodies observed in malaria infection are not a consequence of a generalized and non-specific polyclonal activation.

Adolescent↗
PubMed1984

Islet-cell antibodies (ICA-CFICA) and HLA genotypes in 107 IDD patients and their first-degree relatives.

The prevalence of ICA and CFICA in relation to HLA-DR genotypes was analyzed in 107 insulin-dependent diabetic (IDD) patients with a duration of IDD ranging from onset to 30 years, and 247 nondiabetic first-degree relatives. In 46 patients tested at onset of IDD, the prevalence of ICA and of CFICA was 61 and 50%, respectively; with the longer duration of IDD, the prevalence of CFICA decreased more rapidly than that of ICA. No significant association was observed between ICA and any HLA allele in patients tested from onset till 2 years after onset. However, a higher prevalence of ICA was found in DR3 positive patients with a duration of IDD of more than 2 years (p less than 0.02). Among the healthy relatives, the prevalence of ICA was 7% in parents and 13% in siblings; one out of 101 siblings had CFICA. No association was found between ICA and any HLA marker. The presence of ICA in sibs was independent of the number of haplotypes they shared with the IDD proband: among the 13 ICA-positive healthy sibs, one shared 2 haplotypes, nine shared 1 haplotype and three shared no haplotype with the proband, which is not different from the random distribution.

Adolescent↗
PubMed1984

A new anti-liver-kidney microsome antibody (anti-LKM2) in tienilic acid-induced hepatitis.

The sera of 131 patients with anti-liver-kidney microsome antibodies (anti-LKM) detected between 1973 and 1979 in two different laboratories were re-examined. (1) Eighty-six anti-LKM corresponded to the description given by Rizzetto, Swana & Doniach (1973), with a pattern of fluorescence predominating on the 3rd portion of the proximal tubules (P3). This group comprised 45 cases of idiopathic chronic hepatitis or idiopathic cirrhosis and one case of halothane-induced hepatitis. (2) Forty-five anti-LKM gave a different pattern on male mouse liver and male rat kidney: (a) fluorescence was greater on centrolobular than on periportal hepatocytes; (b) the first and second portions of proximal tubules (P1 and P2) predominated over P3; (c) P1 fluorescence was equally intense as P2 and (d) P3 cells were heterogeneous with one cell out of 20 more positive than the rest. Absorption tests confirmed that the corresponding antigen was also present in the liver microsomal fraction. A retrospective clinical study discovered tienilic acid-induced hepatitis in all cases. We suggest naming this new antibody 'anti-LKM2'.

Adolescent↗
PubMed1984

[Comparison of human tumor cells (Hep 2) and rat liver for the detection of antinuclear antibodies by indirect immunofluorescence].

Indirect immunofluorescent detection of anti-nuclear antibodies was conducted on sections of rat liver and on smears of human Hep 2 tumour cells in the serum of 1017 patients. Overall, the Hep 2 cells gave titres superior by 1 or 2 dilutions. Taking into account this difference, a good agreement was observed between the 2 cellular reagents in 83 per cent of the sera tested. The divergences, which affect almost one half of the positive sera, are largely due to the presence of anti-centromere antibodies, anti-nuclear antibodies giving a patchy "M3" appearance to the Hep 2 cells and, most importantly, anti-nucleolar antibodies. Such differences demonstrate that there are major qualitative or quantitative antigenic differences between the nuclei of rat hepatocytes and those of Hep 2 cells. Although technically rat liver and Hep 2 cells were found to be fairly easy to use and interpret, only a large comparative study of human pathology will be able to determine which is the better reagent for the routine detection of anti-nuclear antibodies.

Animals↗
PubMed1983

[Anti-smooth-muscle antibody activity of monoclonal IgM in Waldenström's disease].

The authors report a case of Waldenstrom disease in which the IgM kappa immunoglobulin had an anti-smooth-muscle activity at a very high titre (1/100 000). This activity was found in the purified IgM but not in the Fab fragment; nevertheless, the immunofluorescence inhibition by this fragment is evidence in support of the anti-smooth-muscle activity of the IgM. The IgM specificity in this patient is different from the anti-smooth-muscle antibodies already described.

Antibodies, Monoclonal↗
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↗
PubMed1983

Specificity of auto-antibodies in malaria and the role of polyclonal activation.

Sera of 173 individuals living in a malaria endemic region in Upper Volta (Donsé village) were screened for the presence of 14 auto-antibodies by the indirect immunofluorescent and/or passive haemagglutination techniques. At least one auto-antibody (AAb) was detected in sera of 72% (124 out of 173) subjects. No differences in the AAb frequency was observed in the sex or age groups. Conversely, a significant relationship between a high frequency of auto-antibodies, high malaria antibody titres and high IgM levels was observed. Antinuclear antibodies (ANA) (87% of total AAb) and particularly those of speckled pattern of fluorescence were by far the most frequently observed. Smooth muscle antibodies (SMA), heart and gastric parietal cell antibodies and thyroglobulin antibodies were found at a normal frequency. This selective increase in the frequency of one AAb (and not of others) cannot, in our opinion, result from a non-specific polyclonal activation. An alternative hypothesis involving both a specific antigenic and a non-specific mitogenic signal is proposed.

Adolescent↗