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S Spitzauer

Publications and source records attributed to S Spitzauer.

54 records · Page 3Linked to original sources
PubMed1997

Specificities of platelet autoantibodies in patients with lupus anticoagulants in primary antiphospholipid syndrome.

We have studied target platelet antigens in 22 patients with lupus anticoagulants and a primary antiphospholipid syndrome in order to determine whether any specificities of platelet autoantibodies are correlated with thromboembolism, and if these antibodies cross-react with phospholipids, which would suggest their role in the development of thromboembolic disease. Platelet counts were median 203 x 10(9)/l, range 100-298 x 10(9)/l. Platelet antibodies were found in six thrombocytopenic patients and in further nine patients. All these 15 patients had antibodies against GPIIb/ IIIa, five patients against GPIb/IX, and six patients against GPIV. Anti-GPIb/IX and -GPIV occurred only in combination with anti-GPIIb/IIIa antibodies. There was no correlation between the presence of detectable platelet antibodies or any of their glycoprotein specificity and thrombocytopenia or the history of a thromboembolic disease. Eluates from platelets contained only GPIIb/IIIa reactivities, but neither anti-GPIb/IX nor anti-GPIV. None of the eluates contained lupus anticoagulant activity. In one case, the platelet eluates contained anti-GPIIb/IIIa and anticardiolipin IgG antibodies. These results suggest that in patients with a primary antiphospholipid syndrome the presence of platelet autoantibodies neither indicate a risk for thromboembolic disorder nor have lupus anticoagulant activity.

Adolescent↗
PubMed1997

Natural latex, grass pollen, and weed pollen share IgE epitopes.

BACKGROUND: Because of the frequent use of natural latex products, IgE-mediated reactions to latex proteins represent an important health threat in industrialized countries. Although several latex allergens have been characterized and IgE cross-reactivities with allergens present in plant-derived food have been described, limited information is available regarding the presence of common IgE-binding components in latex and plant pollen. METHODS: By using serum IgE from 56 individuals with latex allergy, the IgE-binding components in ammoniated latex milk and latex glove extracts were characterized by immunoblotting. The presence of cross-reactive IgE-binding components in the different latex extracts, extracts from mugwort, ragweed, timothy grass pollen, and recombinant birch pollen allergens (Bet v 1 and Bet v 2 [birch profilin]) was studied by immunoblot inhibitions and quantitative competition experiments. The involvement of carbohydrates in the constitution of cross-reactive IgE epitopes was studied by periodate treatment of extracts. RESULTS: Although sera from certain individuals with latex allergy showed IgE reactivity with protein bands of different molecular weights in Western-blotted latex milk and glove extracts, both extracts contained common IgE epitopes. Although preincubation with recombinant Bet v 1 and Bet v 2 did not significantly inhibit IgE binding to latex proteins, weed and, in particular, timothy grass pollen extract strongly inhibited IgE binding to latex allergens. The cross-reactive IgE epitopes were sensitive to periodate treatment. CONCLUSIONS: Mugwort, ragweed, and timothy grass pollen share IgE epitopes with glycoprotein latex allergens. The presence of common epitopes might in part explain clinical symptoms in patients allergic to pollen on contact with latex.

Adolescent↗
PubMed1997

Major cat and dog allergens share IgE epitopes.

BACKGROUND: Patients allergic to cats and dogs frequently display IgE reactivity against allergens from different animals, suggesting a cross-sensitization to common allergenic determinants. Although albumins have been recognized as relevant cross-reactive allergens, little is known regarding cross-reactive epitopes of the major cat and dog allergens. OBJECTIVE: In this study, sera from patients allergic to cats and/or dogs were used to investigate the presence of common IgE epitopes among the major cat and dog allergens. METHODS: The IgE reactivity profile of 109 patients who were allergic to allergens from several species of animals was determined with nitrocellulose-blotted cat and dog allergens. Sera from patients who were strongly allergic to the major cat and dog allergens were tested for the presence of cross-reactive IgE antibodies by one-dimensional and two-dimensional immunoblot inhibition experiments and by quantitative measurements obtained with the CAP-FEIA system (Pharmacia). RESULTS: Sixty-eight of 109 patients with animal allergy showed IgE reactivity to cat allergens and dog allergens. Sera from patients with both cat and dog allergy detected allergens of similar molecular weight in nitrocellulose-blotted cat and dog hair/dander extracts. Common, as well as species-restricted, IgE epitopes of the major cat and dog allergens could be demonstrated by IgE inhibition studies. CONCLUSION: Shared IgE epitopes of the major cat and dog allergens may provide an explanation for the clinical observation that allergies to cats and dogs are frequently associated.

Albumins↗
PubMed1997

Characterization of allergens from deer: cross-reactivity with allergens from cow dander.

BACKGROUND: Animal hair/dander proteins frequently cause Type I hypersensitivities. Species-specific and broadly cross-reacting allergens have been characterized in the past. METHODS: Sera from eight individuals suffering from symptoms due to exposure to deer and deer-derived products were investigated by immunoblotting. Extracts from deer, dog, cat, horse, rabbit and cow, respectively, were tested for IgE-binding. To reveal cross-reactivities patients' sera were preadsorbed with these extracts prior to testing with deer extract. RESULTS: Deer allergens with the molecular mass of 22 and 25 kD (major allergens), as well as 60 kD were identified. The 22 and 25 kD allergens are cross-reactive with the corresponding cow allergens. CONCLUSION: Deer allergy is a rare sensitization mainly affecting persons exposed to deer, who displayed an atopic disposition. From our results it can be assumed that this hypersensitivity is partly associated with allergy to cow dander.

Adult↗
PubMed1996

Comparison of recombinant timothy grass pollen allergens with natural extract for diagnosis of grass pollen allergy in different populations.

BACKGROUND: Complementary DNAs coding for the major timothy grass pollen (Phleum pratense) allergens Phl p 1, Phl p 2, and Phl p 5 and birch profilin were isolated, expressed as recombinant nonfusion proteins in Escherichia coli, and purified. OBJECTIVE: In this study the in vitro IgE-binding capacity of recombinant Phl p 1, Phl p 2, Phl p 5, and birch profilin and their IgE recognition frequencies were investigated by using sera from different populations. METHODS: One hundred eighty-three sera from patients allergic to grass pollen were obtained from different populations in Europe, Japan, and Canada. The sera were selected according to clinical criteria, skin testing, and RAST (CAP system; Pharmacia, Uppsala, Sweden) and then tested for IgE reactivity with natural and purified recombinant timothy grass pollen allergens by ELISA and Western blot. RESULTS: Most (94.5%) of the patients allergic to grass pollen could be diagnosed with a combination of recombinant Phl p 1, Phl p 2, Phl p 5, and profilin by means of ELISA. Sera that did not react with the recombinant allergens contained low levels of timothy grass pollen-specific IgE. Although considerable variability in IgE recognition frequency of the recombinant allergens was observed in certain populations, a good correlation was found between natural timothy CAP results and the combination of recombinant allergens in all 183 tested sera (r = 0.87). CONCLUSIONS: Despite considerable variability in the IgE recognition frequency, purified recombinant timothy grass pollen allergens (Phl p 1, Phl p 2, Phl p 5) and profilin permitted successful in vitro diagnosis of grass pollen allergy in 94.5% of allergic individuals from different populations. The addition of other recombinant allergens (e.g., recombinant Phl p 4) would only slightly improve the in vitro test sensitivity.

Allergens↗
PubMed1996

Identification of a 60 kd cross-reactive allergen in pollen and plant-derived food.

BACKGROUND: Cross-reactive IgE antibodies were found to be responsible for allergic reactions in patients allergic to pollen on ingestion of food (oral allergy syndrome). So far, the major birch pollen allergen Bet v 1 and birch profilin (Bet v 2) were identified as relevant cross-reactive allergens. OBJECTIVE: In this study we attempted to identify additional cross-reactive plant allergens, which could be responsible for food intolerance in patients allergic to pollen. METHODS: Monoclonal antibodies specific for the major mugwort pollen allergen, Art v 1, representing a 60 kd glycoprotein, were used to detect cross-reactive allergens in other pollens and plant-derived food. The amino acid compositions of the cross-reactive structures were determined, and their resistance against trypsin treatment was investigated. In addition, IgE immunoblot inhibitions were done with the 60 kd mugwort pollen allergen. RESULTS: Monoclonal antibodies specific for the major mugwort pollen allergen, Art v 1, cross-reacted with proteins of comparable molecular weight in fruit and vegetables. Preadsorption of patients' sera with the 60 kd mugwort allergen led to a reduction of IgE binding to components of a similar molecular weight present in different pollen (birch, timothy grass), fruit (apple, peanuts), and vegetable (celery) extracts and reduced IgE binding to apple, kiwi, and celery as determined by RAST inhibitions. CONCLUSION: A cross-reactive plant panallergen, possibly identical to the major mugwort pollen allergen, Art v 1, is described. The allergen represents a protein of approximately 60 kd present in various pollen and plant foods; which is distinct from Bet v 1 and profilin and hence may represent a novel cross-reactive allergen in the oral allergy syndrome.

Allergens↗
PubMed1996

Immunoglobulin E response to human proteins in atopic patients.

The demonstration that human IgE recognizes both exogenous allergens and structurally related human proteins has led to the hypothesis that IgE autoreactivity may be a pathogenic factor in atopic diseases. To determine the frequency of occurrence as well as the disease specificity of this phenomenon, we tested sera from patients with atopic diseases and, for control purposes, from persons with immunologically mediated disorders for serum IgE reactivity with nitrocellulose-blotted human proteins. We found that 12 of 20 sera from atopic patients with pronounced skin lesions contained Western blot-detectable IgE antibodies. Patients suffering predominantly from allergic rhinoconjunctivitis as well as control individuals failed to display serum IgE autoreactivity, but occasionally exhibited elevated serum IgE levels. The molecular weights of the IgE-defined autoantigens ranged predominantly from 10 to 100 kDa. Whereas some of these were expressed in only certain cell types, others were detected in histogenetically different cells. Our results suggest that IgE autoimmunity occurs frequently in atopic dermatitis patients and may be of pathogenic relevance for the chronicity of skin manifestations typical of this disease.

Antibody Specificity↗
PubMed1996

Lipoproteins accumulate in immune deposits and are modified by lipid peroxidation in passive Heymann nephritis.

Proteinuria in passive Heymann nephritis is primarily caused by reactive oxygen species that are produced by glomerular cells. Reactive oxygen species apparently exert their damaging effects on the glomerular filter by lipid peroxidation and subsequent adduct formation on matrix proteins of glomerular basement membranes. This raised the question as to the source of polyunsaturated fatty acids required as substrates for lipid peroxidation. Here we have localized by immunocytochemistry rat apolipoprotein E and apolipoprotein B within subepithelial immune deposits. Moreover, apolipoprotein B extracted from isolated glomeruli of proteinuric passive Heymann nephritis rats shows degradation and lipid peroxidation adduct formation, similar to apoproteins of oxidized lipoproteins in atherosclerotic lesions. These data provide evidence that lipoproteins accumulate within immune deposits and suggest that their lipids generate lipid-peroxidation-derived reactive compounds.

Animals↗
PubMed1995

IgE cross-reactivities against albumins in patients allergic to animals.

BACKGROUND: Type I allergic symptoms and severe asthma in particular are frequently caused by animal hair/dander proteins, among which albumins are possible cross-sensitizing allergenic components. METHODS: The significance and degree of IgE-cross-reactivities against various albumins were studied in a representative number (n = 200) of patients allergic to animals with hair/dander extracts, purified albumins from different animals, and a recombinant dog albumin fragment expressed in lysogenic Escherichia coli Y1089 and purified as a beta-galactosidase fusion protein. RESULTS: Despite a high degree of sequence homology among different albumins, a remarkable variability of IgE cross-reactivities was observed, indicating that some patients were sensitized preferentially against certain albumins. Most of the patients allergic to albumins, however, reacted to dog, cat, and horse albumin, which also bound a high percentage of albumin-specific IgE. CONCLUSION: The purified recombinant dog albumin fragment, representing 265 amino acids of the mature protein, bound IgE from all 15 patients allergic to albumin tested suggesting its potential usefulness for diagnosis and perhaps therapy.

Albumins↗
PubMed1995

Hydrocortisone enhances total IgE levels--but not the synthesis of allergen-specific IgE--in a monocyte-dependent manner.

Recently, hydrocortisone (HC), when combined with human IL-4, has been reported to increase IgE levels in supernatants (SN) of in vitro cultured leucocytes. In this study we investigated the influence of HC on allergen-specific IgE synthesis. Moreover, we examined the relevance of different cell types in this respect. Peripheral blood mononuclear cells (PBMC), T-cell depleted PBMC, CD14-depleted PBMC and highly purified B cells from 10 allergic (birch pollen and/or grass pollen) patients and five non-allergic individuals were investigated. The cells were incubated with HC and/or recombinant human IL-4 (rIL-4) for 8 days. A considerable increase of total IgE was observed in HC/rIL-4-stimulated cultures compared with rIL-4 alone, HC alone or non-stimulated cultures. We demonstrate that this effect depends on the presence of monocytes in in vitro cultures. These results were seen in every experiment, irrespective of healthy or atopic state of the blood donor. The increase of IgE could not be attributed to a rise of birch pollen-and/or grass pollen-specific IgE in patients allergic to these allergens, as shown by IgE-immunoblot. Radio-allergosorbent test (RAST) investigations of HC/rIL-4-stimulated cells cultures from allergic and non-allergic patients confirmed that HC/rIL-4-induced elevated IgE production was also not due to increased production of IgE, specific for important aero-allergens (pollens, house dust mite or animal dander). Therefore we conclude that newly synthesized IgE is not specific for allergens, but that sequential isotype switching in human B cells leads to increased polyclonal IgE production.

Allergens↗
PubMed1994

Molecular characterization of dog albumin as a cross-reactive allergen.

Indoor allergens comprise a group of allergenic proteins that are commonly derived from house dust mite and cat and dog dander. In addition to the two major dog allergens (molecular weights: 19 and 23 kd), dog albumin represents an important allergen for up to 35% of patients who are allergic to dogs. In IgE immunoblot inhibition studies and histamine release tests it has been demonstrated that patients who react to dog albumin exhibit IgE reactivity with purified albumins from cat, mouse, chicken, and rat. The proportion of dog-specific IgE directed against dog albumin was determined for patients allergic to dog albumin, and it ranges from 70% to 90%. By IgE immunoscreening of a lambda gt11 expression library from a dog salivary gland, we identified a number of reactive complementary DNA clones. All patients with IgE reactivity against natural dog albumin displayed IgE reactivity to the beta-galactosidase fusion protein encoded by clone 54c, which was therefore assumed to contain major IgE epitopes of dog albumin. The deduced amino acid sequence of clone 54c was compared with the Swiss-Prot library, and significant sequence homologies were found with albumins from different species (human: 82.6%, pig: 81.8%, cattle: 77.3%, sheep: 78.8%, mouse: 75.8%, and rat: 76.2%). Several other IgE-positive clones hybridized with oligonucleotides that were prepared according to this sequence. Partial complementary DNA coding for dog albumin fragments may be considered a useful tool for further characterization of major IgE epitopes of dog albumin.

Allergens↗
PubMed1993

Characterisation of dog allergens by means of immunoblotting.

Sera from 75 patients with clinical type I allergy against dogs were investigated by means of immunoblotting using extracts prepared from dog hair/dander (CAN XI D) and saliva. In addition, selected sera were tested on extracts made of hair, skin, salivary glands (parotis and submandibularis), serum and liver. A 69-kD IgE-binding protein was identified in all extracts tested with an incidence of approximately 40% and shown to be dog albumin by means of inhibition experiments. In 96% of patients' sera IgE antibodies reactive with a 19-kD and/or a 23-kD protein of the hair/dander extract (CAN XI D) were observed. IgE binding to a 23-kD band was also detected in the hair and saliva extracts, but not in skin, salivary gland, serum and liver extracts. A 19-kD IgE-binding protein was strongly expressed in skin and to a lesser degree in saliva, but not in hair, serum and liver. Preincubation of patients sera with the hair extract and subsequent probing with the hair/dander extract (CAN XI D) inhibited IgE binding to the 23 kD protein whereas preincubation with the skin extract abolished IgE binding to the 19-kD protein. Using the hair/dander extract as inhibitor, IgE binding to the 19- and 23-kD proteins of saliva was abrogated. Thus it is concluded that the 23-kD protein is preferentially expressed in hair and saliva whereas the 19-kD protein is found in saliva and skin. Furthermore these two proteins are likely to represent immunologically independent major allergens.

Adolescent↗
PubMed1993

Evaluation of laboratory data by conventional statistics and by three types of neural networks.

Sixty-three patients with lung (34 small-cell, 18 squamous, 11 adeno-) carcinomas and 43 patients with benign lung diseases were characterized with seven tumor markers: neuron-specific enolase (NSE); cancer antigens CA 19-9, CA 125, CA 15-3, and CA 50; carcinoembryonic antigen (CEA); and tissue polypeptide antigen. Diagnosis had been established by histological examination after surgery and used for classification. After vector transformation, the tumor marker data were fed into neural networks (NNs) based on three different types of learning algorithms: backpropagation (BP), competitive learning (CL), and Hopfield (H). For comparison, the data were evaluated with multivariate stepwise discriminant analysis (MVSDA). BP-NNs are equal to (NSE, CA 19-9, CEA) or better than (100% correct classification when using all seven markers) MVSDA in assigning the correct diagnosis to the patients. Cross-validation data yielded shrinkage effects ranging from 0% to 12.5%. Quality-control (QC) data were evaluated by traditional QC algorithms and compared with the results obtained by a BP-NN. The results show that the BP-NNs could only partly fulfill the tasks of three QC algorithms regarding the violation of static borders but gave good results with respect to dynamic changes.

Biomarkers, Tumor↗
PubMed1991

The immunoregulatory influence of transforming growth factor beta in thyroid autoimmunity: TGF beta inhibits autoreactivity in Graves' disease.

The immunoregulatory influence of transforming growth factor beta (TGF beta) was studied in patients with Graves' disease and in normal controls. Special attention was given to determine how TGF beta affects the interaction between thyroid epithelial cells and T lymphocytes. Human recombinant TGF beta 1 (rTGF beta 1) was immunosuppressive in patients with Graves' disease and in controls. In both groups it inhibited the proliferation of peripheral blood mononuclear cells and of peripheral and thyroid derived T cell lines and clones in response to non-specific stimuli. It also decreased the number of serine esterases expressing cytotoxic T cells and suppressed the recognition of thyroid epithelial cells by thyroid autoantigen specific T cell clones. Inhibition of autoantigen recognition was not only observed when rTGF beta 1 was added to the thyroid epithelial cell/lymphocyte co-culture, but was also found when thyroid epithelial cells were preincubated with rTGF beta 1, which was then removed before the initiation of co-culture. This was probably as a result of a decrease in the antigenicity of the target cells, as rTGF beta 1 also suppressed thyroid peroxidase as well as HLA class II autoantigen expression, in cultured thyroid epithelial cells. These results demonstrate that TGF beta may exert a variety of down-regulatory influences in Graves' disease. It may be of importance for the suppression of autoaggression in persons predisposed to autoimmunity; may be quantitatively overrun by immunostimulatory influences in the acute phase of the disease; and may be important for the induction of remission in patients with Graves' disease.

Adolescent↗
PubMed1991

Allergen profiles of dog hair and dander, body fluids and tissues as defined by immunoblotting.

The sera from 25 patients with clinical type I allergy against dogs were investigated by means of immunoblotting, using extracts of dog hair/dander, skin, hair, saliva, salivary gland, serum and liver. 96% of the patients' sera showed IgE antibodies reactive with 19- and 23-kilodalton (kDa) proteins in the hair/dander extract. The 23-kDa IgE-binding protein was preferentially detected in the hair extract and saliva but not in skin, salivary gland, serum and liver extracts. The 19-kDa band was strongly expressed in skin, but not in hair, serum and liver. Inhibition experiments using the 23-kDa containing extract prepared from hair and the 19-kDa containing extract prepared from skin revealed that these two proteins are likely to be immunologically independent allergens.

Adolescent↗
PubMedDate not supplied

Genetically engineered and synthetic allergen derivatives: candidates for vaccination against type I allergy.

Type I allergy, a hypersensitivity disease affecting almost 20% of the population worldwide, is based on the IgE recognition of otherwise harmless antigens (i.e., allergens). Allergen-induced crosslink of effector cell-bound IgE antibodies leads to the release of biological mediators and thus to immediate disease symptoms (allergic rhinitis, conjunctivitis and asthma). Specific immunotherapy, the only causative treatment of Type I allergy, is based on the administration of increasing doses of allergens to allergic patients in order to yield allergen-specific non-responsiveness. Major disadvantages are 1. that current forms of allergen immunotherapy are performed with allergens difficult to standardize which cannot be matched to the patients reactivity profile and 2. that the administration of active allergen preparations can cause anaphylactic side effects. Through the application of molecular biological techniques many relevant environmental allergens have been produced as active recombinant proteins which allow component-resolved allergy diagnosis and thus represent the basis for patient-tailored forms of immunotherapy. Here we review molecular strategies which have been recently applied to generate genetically engineered and synthetic hypoallergenic allergen derivatives for patient-tailored and safe vaccination against Type I allergy.

Allergens↗