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Biomedical subjects

F Hiepe

Publications and source records attributed to F Hiepe.

At least 73 records · Page 4Linked to original sources
PubMed1996

Differential recognition of the 52-kd Ro(SS-A) antigen by sera from patients with primary biliary cirrhosis and primary Sjögren's syndrome.

Antibodies against the 52-kd Ro(SS-A) protein are significantly associated with the primary Sjogren's syndrome (pSS). A small proportion of patients suffering from primary biliary cirrhosis (PBC) with secondary Sjogren's syndrome (PBC/SS) who are serologically characterized by antimitochondrial type 2 antibodies also express anti-52-kd Ro(SS-A) antibodies. The primary B-cell-derived antigenic responses by autoimmune sera were analyzed in both entities using truncated recombinant proteins to examine whether different epitopes are associated with these diseases. Sera were collected from 25 patients with pSS and 9 anti-52-kd Ro(SS-A)-positive patients suffering from PBC/SS. B-cell epitope mapping was performed using different 52-kd Ro(SS-A) fusion proteins in enzyme-linked immunosorbent assay (ELISA) and immunoblotting. Sera from patients with pSS showed the broadest reactivity against antigenic epitopes at AA 153-245 compared to the significantly limited reactivity against AA 228-245 of sera from patients with PBC. B-cell epitopes within AA 190-245 represent immunodominant epitopes recognized by pSS sera in a significantly higher degree than by PBC sera, which react predominantly with AA 228-245 (P < .0001). Anti-La(SS-B) antibodies were significantly associated with anti-52-kd Ro(SS-A) in sera from patients with pSS compared with PBC patients (P < .025). Thus, the antibody response to 52-kd Ro(SS-A) in PBC appears to be induced differently than in pSS. Although a limited immune response to 52-kd Ro(SS-A) occurs in PBC/SS patients, a more extended epitope spreading is evident in patients with pSS.

Adult↗
PubMed1996

Behet's syndrome with pulmonary involvement-combined therapy for endobronchial stenosis using neodym-YAG laser, balloon dilation and immunosuppression.

We present a case report of a patient suffering from Behet's syndrome with pulmonary involvement. The development of endobronchial granulomatosis in the bronchus intermedius and right upper lobe bronchus led to severe bronchial stenosis and dyspnoea. Also aphthous ulcerations in the bronchial mucosa occurred. Treatment of the granulomatous stenosis consisted of Neodym-YAG laser resection and immunosuppression. On follow-up there was a recurrence of the stenosis, characterised by fibrotic strictures. Therefore a balloon dilation was performed and immunosuppression instituted, which led to an increase in airway diameter and a reduction in dyspnoea. These clinical results suggest that recanalisation therapy with Neodym-YAG laser and/or balloon dilation with additional immunosuppression is suitable in benign stenosis (granulomatous or fibrotic), caused by Behet's disease.

Adult↗
PubMed1996

Diagnosis of alveolitis in interstitial lung manifestation in connective tissue diseases: importance of late inspiratory crackles, 67 gallium scan and bronchoalveolar lavage.

The diagnostic relevance of bronchoalveolar lavage (BAL) and associated non-invasive findings in connective tissue diseases (CTD) has not been established regarding alveolitis so far. The goal of the study was to determine the relations between BAL cell differential count and findings of non-invasive diagnostic procedures for alveolitis to predict the clinical value of BAL in CTD. One hundred-five patients (92 non-smokers; 13 smokers) with CTD (73 patients with systemic sclerosis, 19 with systemic lupus erythematosus, 13 with primary Sjögren's syndrome) had symptoms or signs of lung involvement and were further examined (lung function test, chest radiography, thoracic computed tomography, 67 gallium scintigraphy and BAL). The relations between BAL in middle lobe and cell count differentiation to non-invasive investigations were analyzed by logistic regression. In all CTD patients investigated a pulmonal involvement occurred based on non-invasive methods. Regarding non-invasive methods, alveolitis determined by BAL cell differential count was significantly associated with an increased 67-gallium uptake and late inspiratory crackles (P < 0.01), and to a lesser extent with an abnormal interstitial pattern in CT (P < 0.055). Parameters of lung function and laboratory parameters were related to alveolitis using multivariate testing. Considering the alveolitis subtype (granulo- or lymphocytosis), only a reduced FEV1 showed a relationship to granulocytic alveolitis (P < 0.01). Late inspiratory crackles and increased 67 gallium uptake as non-invasive diagnostic findings point out alveolitis in CTD remarkably. Therapeutic and prognostic aspects necessitate BAL to specify the type of alveolitis (lymphocytosis or granulocytosis or mixed forms) in CTD patients with lung manifestation. Non-invasive diagnostic procedures cannot predict the type of alveolitis sufficiently.

Adult↗
PubMed1996

Anti-52 kDa Ro(SSA) autoantibodies in different autoimmune diseases preferentially recognize epitopes on the central region of the antigen.

OBJECTIVE: Antibodies against the 52 kDa Ro(SSA) protein are an important laboratory variable in autoimmune diseases, most notably in the diagnosis of primary Sjogren's syndrome (SS), congenital heart block (CHB), and certain varieties of systemic lupus erythematosus (SLE). However, there is controversy about the differential reactivity of these sera, both with regard to immunogenic regions on the target protein and the respective antibody titers. Therefore, sera from various autoimmune diseases were tested against a broad panel of recombinant 52 kDa Ro(SSA) fusion proteins. METHODS: Sera were obtained from 20 patients with SLE, 10 with primary SS, 15 children with CHB, 6 healthy anti-52 kDa Ro(SSA) positive infants born to mothers with SLE and 7 anti-52 kDa Ro(SSA) positive patients with primary biliary cirrhosis/secondary SS. Epitope mapping was performed using different fusion proteins in ELISA and immunoblot. RESULTS: All sera reacted with whole recombinant antigen as well as with the protein carrying the amino acid sequence (AA) 1-245. The proportion of positive sera against the 52kDa Ro fusion proteins tested was found in descending order in patients with CHB, down to primary SS, the healthy infants group, patients with SLE and finally primary biliary cirrhosis/secondary SS. In general, CHB and primary SS sera exhibited the broadest reactivity against the recombinant protein compared to the limited and lower reactivity of sera from patients with primary biliary cirrhosis. Sera from infants with CHB had significantly higher antibody levels to AA 1-245 compared to SLE sera (p < 0.0005) and to sera from healthy infants born to SLE mothers (p < 0.05), as well as to serum samples from patients with primary biliary cirrhosis/SS (p < 0.005). The strongest antigenicities recognized by anti-52 kDa Ro(SSA) autoantibodies are located within the AA 197-245 region that represents an essential epitope. Further antigenic sites preferentially recognized by SS, CHB, and healthy infant sera are located within AA 153-196. CONCLUSION: Thus, the central region AA 153-245 is the major immunogenic region of the 52 kDa Ro(SSA) antigen containing a strong antigenic epitope between AA 197-245. The antibody response is directed to this major antigenic region regardless of the underlying autoimmune disease. However, the strikingly different quantities of antibody levels and the recognition of epitopes on AA 153-196 may be associated with different disease expressions.

Adolescent↗
PubMed1996

Production of autoantibodies against DNA and collagen after inoculation of rabbits with Trypanosoma equiperdum.

The aim of the study was to investigate the induction of autoantibodies in rabbits after the inoculation with Trypanosoma equiperdum. Eight female rabbits were inoculated s.c. with 5 x 10(6) parasites of Trypanosoma equiperdum. Four of these animals were treated with Diminazen (Berenil) at a dosage of 28 mg per rabbit by intramuscular injection 35 days p. i. Two additional non-infected rabbits served as negative controls. 9 days p.i. all infected animals possessed serum antibodies against Typanosoma equiperdum. Titers peaked to 1:2048, measured between 14 and 30 days p.i. and were persistent until the end of examinations. In parallel, there was an increase of anti-dsDNA and anti-collagen autoantibodies, but not of autoantibodies against recombinant U1RNP and La antigens. In comparison to patients with systemic lupus erythematosus, the anti-DNA binding of rabbit's sera was reduced more strongly in presence of increasing salt concentrations. In addition, the sera of inoculated rabbits recognized several unknown bands of a cell extract in immunoblotting. The parallel increase of antibodies against Trypanosoma, control foreign antigens, DNA and collagen suggests a polyclonal stimulation of the immune system. It was concluded that this rabbit model seems to be sufficient to investigate the mechanisms which are able to induce autoimmune phenomena.

Animals↗
PubMed1995

Quantitative polymerase chain reaction using a DNA hybridization assay based on surface-activated microplates.

A method for DNA quantification on microplates based on the hybridization between single-stranded target and solid-phase bound capture DNA is presented. Binding of the capture DNA to the microplates was attained by surface activation using organosilanes. Detection of hybridized DNA was performed by an enzyme-linked assay taking advantage of the labeled target DNA. Basic test characteristics are described and application examples are given demonstrating its feasibility for a quantitative PCR (QPCR). The QPCR was carried out by coamplifying an immunoglobulin complementarity determining region 3 (CDR3)-coding plasmid DNA with a synthetic internal standard (IS). IS and plasmid CDR3 both shared primer binding sites and produced length-identical amplicons. The amplified DNA was quantified following differential hybridization with IS- and plasmid-specific capture probes. Based on the product ratios of plasmid to IS, the initial amounts of plasmid DNA were calculated. This way, QPCR was shown to be capable of detecting initial concentration differences of plasmid DNA of about 30%.

Base Sequence↗
PubMed1995

Significantly increased maternal and fetal IgG autoantibody levels to 52 kD Ro (SS-A) and La(SS-B) in complete congenital heart block.

Antibodies to Ro(SS-A) are an important laboratory parameter of congenital heart block (CHB), but the maternal presence of anti-Ro(SS-A) antibodies does not always lead to this fetal acquired autoimmune disease. The current study investigated quantitative and qualitative differences of anti-52, -60 kD Ro(SS-A), 0La(SS-B) and -U1RNP(-C, -A, -68 kD) autoantibodies (either IgG or IgM) in sera derived from 16 infants with CHB and their mothers compared to eight healthy anti-Ro(SS-A) positive infants (controls) born to SLE mothers. No serum sample contained IgM auto-antibodies of the specificities investigated. Anti-60, 52 kD Ro(SS-A) and La(SS-B) IgG antibodies coincided in 9/16 CHB cases, exclusively (P < 0.05). Associated anti-52 kD Ro(SS-A) and -La(SS-B) IgG antibodies were detected in 14/16 CHB and in 3/8 control cases (P < 0.05). Anti-U1RNP 68 kD antibodies occurred in 1/16 CHB infants and in 4/8 controls. In general, newborn and maternal antibody patterns and reactivities were similar in all cases investigated. The fetal CHB sera contained significantly higher IgG levels of anti-52 kD Ro(SS-A) (P < 0.005) and -La(S-B) (P < 0.015) compared to control samples. Sera from mothers with CHB children had significantly higher levels of anti-52 kD Ro(SS-A) (P < 0.015) and -La(SS-B) (P < 0.015) IgG antibodies than those of the control group. Thus, the coincidence of anti-52 kD, -60 kD Ro(SS-A) and -La(SS-B) IgG antibodies as well as significantly increased levels of antibodies to 52 kD Ro(SS-A) and La(SS-B) are associated with evidence of complete congenital heart block. The data suggest that the known associated humoral autoimmune findings are exclusively of maternal origin.

Autoantibodies↗
PubMed1995

Enhanced membrane expression of the 52 kDa Ro(SS-A) and La(SS-B) antigens by human keratinocytes induced by TNF alpha.

OBJECTIVE: To investigate the membrane expression of the 52 kDa Ro(SS-A) and La(SS-B) antigens in human keratinocytes under the influence of an important mediator of inflammation, TNF alpha. METHODS: Keratinocytes, isolated from human skins obtained at circumcision and identified using monoclonal antibodies, were treated with tumour necrosis factor alpha (TNF alpha) and incubated with antibodies to 52 kDa Ro(SS-A) isolated and purified from patients with systemic lupus erythematosus or Sjögren's syndrome, with mouse monoclonal antibody to La(SS-B), and (as controls) with sera from normal healthy blood donors and a mouse monoclonal antibody to U1RNP 68 kDa. Membrane expression of the 52 kDa Ro(SS-A) and La(SS-B) antigens was detected using cyto enzyme linked immunosorbent assays (ELISAs), laser scanning microscopy, and indirect immunofluorescence. RESULTS: After the incubation with TNF alpha, cyto ELISA revealed a significantly increased membrane binding of 52 kDa Ro(SS-A) antibodies, with a maximum after two hours, followed by enhanced 52 kDa Ro(SS-A) expression during the subsequent 24 hours. The La(SS-B) antigen was expressed rapidly after TNF alpha treatment (within one hour), with a fast decrease to the preincubation value within three hours. Indirect immunofluorescence with fixed normal human keratinocytes confirmed increased 52 kDa Ro(SS-A) and La(SS-B) antigen expression after the incubation with TNF alpha. CONCLUSIONS: TNF alpha mediates 52 kDa Ro(SS-A) and La(SS-B) autoantigen surface expression on human keratinocytes, and may be an important factor both in antibody induction and in the initiation of immunopathogenic processes which occur after antibody binding in autoimmune dermatitis.

Antigens, Surface↗
PubMed1995

Effects of methylprednisolone and 21-aminosteroids on mitogen-induced interleukin-6 and tumor necrosis factor-alpha production in human peripheral blood mononuclear cells.

The compounds U-74389G (16-desmethyl tirilazad) and U-74500A are two of the novel series of nonglucocorticoid 21-aminosteroids (or lazaroids) which mimic the high-dose neuroprotective pharmacology of the glucocorticoid methylprednisolone (MP) in the injured CNS. Despite structural analogies to MP, it has been shown previously for a variety of endpoints that lazaroids are devoid of classical glucocorticoid effects. Our objective here was to measure the immunosuppressive effects of these lazaroids directly. Specifically, we have compared the in vitro effects of MP, U-74389G, and U-74500A on the mitogen-induced cytokine production in human peripheral blood mononuclear cells, which is known to be very sensitive and perhaps the most clinically relevant parameter reflecting immunomodulation. We show that, in contrast to the glucocorticoid MP, both lazaroids at therapeutically relevant concentrations have no significant inhibitory effects on stimulated interleukin-6 and tumor necrosis factor-alpha production, neither via residual glucocorticoid receptor-mediated activities nor via direct physicochemical effects on cellular membranes. These results strongly support the view that lazaroids lack glucocorticoid activities, but rather exert their tissue protective effects via mechanisms that are independent of glucocorticoid-receptor binding.

Cells, Cultured↗
PubMed1994

Detection of autoantibodies to Ro(SS-A), La(SS-B) and U1RNP in different congenital heart rhythm disorders using immunoblot and enzyme immunoassay.

The aim of the study was to determine if autoantibodies have distinctive qualitative or quantitative characteristics in children with congenital heart rhythm disorders compared to unaffected infants. Sera of fifty-three infants with different heart rhythm disorders and eight unaffected children born to SLE mothers were tested for antibodies to Ro(SS-A), La(SS-B) and U1RNP (including recombinant A-, C-, 68 kD-proteins) using enzyme immunoassays and immunoblot. 21 sera from affected and 8 sera from healthy children reacted in counter-immunoelectrophoresis with Ro(SS-A). 8/8 infants with third degree atrioventricular (AV)-block, 4/8 with first degree AV-block, one with sinusbradyarrhythmia (SB) and another with SB/first degree AV-block were anti-52 kD Ro(SS-A) positive compared to 7/8 healthy infants. Infants with third degree AV-block had significantly higher anti-52 kD Ro(SS-A) levels than those with the milder heart rhythm disorders (P < 0.01) and the healthy group (P < 0.002). Anti-La(SS-B) antibodies were detected significantly (P < 0.01) and in significantly higher titres (P < 0.01) in AV III than in other types of congenital heart block. Anti-U1RNP-68 kD antibodies were positive in 3/8 healthy, 2/8 first degree AV-block and in 1/8 third degree AV-block cases. Third degree AV-block was more frequently found in female infants (P < 0.05). It was concluded that the influence of antibody levels to the 52 kD Ro(SS-A) and La(SS-B) components and the association of anti-52 kD Ro(SS-A), La(SS-B) and -60 kD Ro(SS-A) antibodies, as well as the sex, on the severity of congenital AV-conduction defects suggests involvement of these factors in the pathogenesis of these disorders.

Adult↗
PubMed1994

The influence of methylprednisolone on the energy metabolism of Ehrlich ascites tumour cells.

Using Ehrlich ascites tumour cells, the short-term effects of the therapeutic glucocorticoid Methylprednisolone (MP) on the cellular energy metabolism were studied. ATP-consuming processes involved in the rapid MP effects were identified indirectly from the effects of MP on cellular oxygen consumption related to the inhibition of respiration by selective inhibitors of Ca(2+)-ATPase and protein synthesis. The effects of MP on plasma membrane permeability for Ca2+ ions and phospholipid turnover were studied directly by using confocal laser scanning microscopy and tracerkinetic measurements, respectively. MP inhibited cellular oxygen consumption, suppressed the inhibitory effect of lanthanum but not that of cycloheximide on oxygen consumption, blocked the [Ca2+]i rise in response to calcium ionophore A 23187, and decreased phospholipid turnover. MP acted instantly in a dose-dependent manner. The observed effects of MP are discussed in relation to the hypothesis that the drug has direct membrane effect affecting plasma membrane permeability and function.

Adenosine Triphosphate↗
PubMed1994

Serologic characteristics in primary biliary cirrhosis associated with sicca syndrome.

BACKGROUND: Patients with primary biliary cirrhosis (PBC) may have coincidental sicca syndrome (SS). The frequencies of SS and the occurrence of the Sjögren's-associated anti-Ro and -La antibodies in PBC patients have been reported at widely varying prevalences. This study investigated whether distinctive serologic characteristics are associated with SS in PBC. METHODS: Forty PBC patients and thirty patients with other types of liver cirrhosis were tested for SS and associated autoantibodies (ANA, AMA 2, anti-Ro, anti-La, anti-U1RNP-A, -C, -68 kD, and rheumatoid factors). RESULTS: Fourteen PBC patients (35%) complained of sicca symptoms, of whom 10 (25%) had a positive Schirmer-I test, and 7 (17.5%) had serologic characteristics similar to those of Sjögren's syndrome. Anti-52-kD Ro antibodies were positive in seven PBC/SS cases (p < 0.025). There was no anti-Ro positive PBC patient without SS. Three patients with PBC/SS with anti-52-kD Ro and anti-smooth-muscle antibodies developed lung fibrosis. No patient in the other cirrhosis group had SS or its characteristic autoantibody findings. CONCLUSIONS: It was suggested that PBC and SS are frequently associated. Anti-52-kD Ro antibodies seem to be a characteristic serologic finding for SS in PBC, suggesting their pathogenic role in autoimmune sialadenitis.

Adult↗