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S O Stapel

Publications and source records attributed to S O Stapel.

36 records · Page 2Linked to original sources
PubMed1996

Screening for coeliac disease in Dutch children with associated diseases.

Our objective was to assess the frequency of coeliac disease in children with associated disorders in the province of "Zuid-Holland". The Netherlands. We therefore screened 115 children with Down's syndrome, 62 children with juvenile rheumatoid arthritis (JRA) and 46 children with diabetes mellitus for CD using the IgA-class of antigliadin, antiendomysium and antireticulin antibodies in serum, and a functional sugar absorption test. The antiendomysium antibody test was the screening test that performed the best. Every patient who has at least one positive test underwent a jejunal biopsy for the diagnosis of CD. No association could be demonstrated between CD and diabetes mellitus. The frequency of CD in Down's syndrome was 7.0%, which is much higher than that found from screening the general population. CD was found in one child with JRA (1.5%), who also had Down's syndrome. We recommend screening for CD in all persons with Down's syndrome using at least the antiendomysium antibody test.

Arthritis, Juvenile↗
PubMed1996

Fel d 1-specific IgG antibodies induced by natural exposure have blocking activity in skin tests.

Cat-allergic patients frequently have IgG antibodies directed against Fel d 1. The aim of this study was to investigate whether these IgG antibodies influence the results of the skin test. Titrated skin tests were performed with Fel d 1 and IgE and IgG antibody levels were measured in 59 patients with cat allergy. Levels of specific IgG against Fel d 1 ranged from less than 0.25 to 3.5 microgram/ml. By means of a multiple regression analysis it was shown that the amount of specific IgG antibodies contributes significantly to the results of the skin test. Presence of specific IgG against Fel d 1 was accompanied by higher skin thresholds for Fel d 1. In conclusion, this study indicates that even low levels of specific IgG, induced by natural exposure to cat allergens, have a blocking effect on the early phase skin reaction.

Adolescent↗
PubMed1995

The decay of house dust mite allergens, Der p I and Der p II, under natural conditions.

BACKGROUND: Fluctuations in the level of mite allergens in domestic house dust are the result of changes in the balance between synthesis, removal and decay. Purely physical forces as well as enzymatic degradation, mediated by house dust inhabiting microbes, may contribute to the decay of allergens in domestic dust. Knowledge about the speed of decay is essential for an understanding of the dynamics of allergen levels. OBJECTIVE: The present study is a quantitative assessment of the speed of decay at nine combinations of temperature (15 degrees C, 20 degrees C and 25 degrees C) and relative humidity (33%, 55% and 75%). METHODS: Samples of mite infested material of an old rug were stored at these temperature/relative humidity-combinations for 6, 12 or 18 months, after the mites were killed by either a freezing treatment or an acaricide (lindane). The microbes living in the rug presumably survive these treatments. Concentrations of Der p I and Der p II + Der f II, in extracts of the rug material, were measured by radio immunoassay. RESULTS: No significant changes in the levels of der p I and Der p II + Der f II, could be detected even after 1 1/2 year at a high temperature and humidity. CONCLUSION: These findings indicate that mite allergens can be extremely stable under normal domestic circumstances.

Allergens↗
PubMed1995

Multiplicity of cross-reactive epitopes on Bet v I as detected with monoclonal antibodies and human IgE.

Six monoclonal antibodies against Bet v I, the major cross-reactive allergen of birch pollen (Betula verrucosa), were obtained. Four did not react with fruits, but two monoclonal antibodies (mAbs) (5H8 and 9C11) were reactive with apple and other fruits. These two cross-reactive antibodies reacted with identical or overlapping sites, but differed in their relative degree of cross-reactivity toward various fruits and hazelnut. Cross-reactive human IgE antibodies reacted with a nonoverlapping epitope, as indicated by results of a two-site radioimmunoassay (RIA) with the fruit-reactive mAb 9C11. By isoelectric focusing (IEF) in conjunction with immunoblotting, a maximum of seven isoforms could be distinguished. Depletion of birch-pollen extract for Bet v I with the most reactive mAb (7F7) removed approximately 95% of the IgE cross-reactivity between birch pollen and apple extract. The remaining 5% cross-reactive material was still capable of inhibiting the binding of IgE to apple allergen completely, and was reactive with mAbs 5H8 and 3C4. By means of IEF/immunoblot, it was shown that these mAbs recognize an isoform of Bet v I that is poorly, if at all, recognized by mAb 7F7. These results illustrate the heterogeneity of Bet v I, both with respect to the cross-reactive sites as well as to the backbone structure. This type of heterogeneity has possible implications for the use of monoclonal antibodies in allergen standardization.

Adult↗
PubMed1995

Grass pollen immunotherapy induces highly cross-reactive IgG antibodies to group V allergen from different grass species.

Sera from two groups of patients receiving grass pollen immunotherapy were tested on IgG reactivity with group V allergen from six different grass species. One group of patients was treated with a mixture of 10 grass species, and the other with a mixture of five. Only Lolium perenne, Dactylis glomerata, and Phleum pratense were present in both mixtures. Although Anthoxanthum odoratum and Secale cereale were absent from the mixture of five, IgG responses to Ant o V and Sec c V were comparable in both patient groups. This reactivity was inhibited for 92-99% with L. perenne extract, illustrating the cross-reactive nature of the IgG antibodies. The presence of A. odoratum and S. cereale in the mixture resulted in only minor amounts of species-specific anti-group V IgG. These results indicate that application of just one grass species in immunotherapy might be sufficient to induce an IgG response that covers other relevant Gramineae species as well.

Allergens↗
PubMed1992

Variability of crossreactivity of IgE antibodies to group I and V allergens in eight grass pollen species.

Crossreactivity to Dactylis glomerata, Festuca rubra, Phleum pratense, Anthoxanthum odoratum, Secale cereale, Zea mays, and Phragmites communis of IgE antibodies against Lol p I or Lol p V was investigated by means of RAST-inhibition. Within a group of sera the degree of crossreactivity was demonstrated to be highly variable. Individual sera were not always equally crossreactive to all pollen species. A high degree of crossreactivity for Group I allergens did not necessarily implicate the same for Group V. Group I and Group V representatives were found to be present in all eight species. It was demonstrated that within this group of grass species significant quantitative and qualitative differences exist, with respect to Group I and Group V allergens. Species with a low phylogenetic affinity to Lolium perenne, like Zea mays and Phragmites communis showed a very low degree of reactivity, even when measured with the most crossreactive sera. A higher taxonomic relationship however, did not always implicate a closer antigenic resemblance. Antigenically both allergens from Zea mays are more similar to Lol p I and Lol p V, than the analogues in Secale cereale.

Allergens↗
PubMed1992

'Horoscope effect' not only for seasonal but also for non-seasonal allergens.

We report on the relation between the month of birth and the chance of developing an IgE antibody response as found in a study sample of 150,000 subjects. Our results confirm that for the three seasonal allergens birch pollen, grass pollen and house dust mite, an increased relative risk was found for subjects born up to 3 months before the main season for that allergen in The Netherlands. For cat and dog allergy an increased relative risk was found from November to January, perhaps reflecting increased exposure to these pets during the winter. Surprisingly, however, also for egg white and cow's milk a clearly increased relative risk was found from November to January and a decreased relative risk in May. These data support the hypothesis of a 'sensitive' period in the first months of life during which allergen exposure is more likely to prime for an allergy later in life. The results with the non-seasonal allergens suggest that another seasonal factor exists which early in life assists (or prevents) priming by allergen.

Allergens↗
PubMed1990

Statistical analysis of IgE antibodies to the common inhalant allergens in 44,496 sera.

A statistical analysis of RAST screening of 44,496 sera, submitted in 1986 and 1987 for routine diagnostic allergic examination, was performed. The sera were tested on a fixed panel of allergens, regardless of the patient's history. The association of a positive RAST with age and month of birth was studied. It was concluded that among the inhalant allergens, house-dust mite was the most frequent sensitizer for all age groups, followed by grass pollen and cat dander. Sensitization to cat dander occurred twice as often as sensitization to dog dander. Among children less than 4 years of age, a different profile of sensitization was found, indoor allergens (mites, animal danders) being more important than outdoor allergens (pollen). Furthermore, we found that children born during December-February had a slightly but significantly greater chance of becoming sensitized to grass pollen compared with children born during September and November (P less than .05). Children born during July-September had a greater chance of becoming sensitized to house dust mite compared with children born during January-March (P less than .05). Finally, it was found that children born during October-December had a greater chance of becoming sensitized to dog dander compared with children born during March-May.

Administration, Inhalation↗
PubMed1989

Characterization with monoclonal and polyclonal antibodies of a new major allergen from grass pollen in the group I molecular weight range.

We have purified a 24/25 kd allergen from orchard grass pollen (Dactylis glomerata) that has an allergenic potency similar to that of the major group I allergen. We provisionally named this allergen grass 4B1 after the monoclonal antibody used for its identification and purification. This monoclonal antibody was obtained by immunizing mice with whole Lolium perenne-pollen extract and by screening the antibody producing hybrids for reactivity with Dactylis glomerata-pollen extract. Grass 4B1 is physicochemically separable from the group I allergen. Polyclonal rabbit antibodies to grass 4B1 do not react with group I allergen or vice versa. Ninety-five sera with IgE antibodies to grass pollen were tested for IgE antibodies to grass 4B1, and greater than 90% was positive in this test. The median response to grass 4B1 was 70% of that to Lol p I.

Allergens↗
PubMed1988

Tau-crystallin/alpha-enolase: one gene encodes both an enzyme and a lens structural protein.

tau-Crystallin has been a major component of the cellular lenses of species throughout vertebrate evolution, from lamprey to birds. Immunofluorescence analysis of the embryonic turtle lens, using antiserum to lamprey tau-crystallin showed that the protein is expressed throughout embryogenesis and is present at high concentrations in all parts of the lens. Partial peptide sequence for the isolated turtle protein and deduced sequences for several lamprey peptides all revealed a close similarity to the glycolytic enzyme enolase (E.C. 4.2.1.11). A full-sized cDNA for putative duck tau-crystallin was obtained and sequenced, confirming the close relationship with alpha-enolase. Southern blot analysis showed that the duck genome contains a single alpha-enolase gene, while Northern blot analysis showed that the message for tau-crystallin/alpha-enolase is present in embryonic duck lens at 25 times the abundance found in liver. tau-Crystallin possesses enolase activity, but the activity is greatly reduced, probably because of age-related posttranslational modification. It thus appears that a highly conserved, important glycolytic enzyme has been used as a structural component of lens since the start of vertebrate evolution. Apparently the enzyme has not been recruited for its catalytic activity but for some distinct structural property. tau-Crystallin/alpha-enolase is an example of a multifunctional protein playing two very different roles in evolution but encoded by a single gene.

Amino Acid Sequence↗
PubMed1985

epsilon-Crystallin, a novel avian and reptilian eye lens protein.

Gel filtration of Peking duck eye lens proteins reveals a component eluting just behind delta-crystallin and comprising approximately 10% of the total soluble protein. The native Mr of this additional component is estimated to be 120000; it appears to be composed of three identical chains of Mr 38000 and pI 7.5. Circular dichroic spectroscopy showed a relatively high alpha-helical content. No immunological cross-reactivity is found with alpha-, beta-, gamma- or delta-crystallins, and partial amino acid sequence determinations likewise failed to reveal any similarity with other known crystallins. We conclude that this protein represents another and novel family of eye lens proteins, for which we propose the designation epsilon-crystallin. epsilon-Crystallin is translated from a 1450-base mRNA, which has been partially purified. epsilon-Crystallin is found scattered among avian and reptilian taxa, but not in other vertebrates. Its rate of evolutionary change seems to be as slow as that of alpha- and beta-crystallins.

Alligators and Crocodiles↗
PubMed1985

Scl-86, a marker antigen for diffuse scleroderma.

More than 300 sera from patients with a connective tissue disease were analyzed with the immunoblotting technique. The presence of autoantibodies against an 86,000-mol wt marker antigen for diffuse scleroderma (Scl-86) was found in 14 out of 33 patients with scleroderma. The presence of anti-Scl-86 antibodies seemed to correlate with the diagnosis of diffuse scleroderma since they were found in 13 out of 22 diffuse scleroderma patients and in only one out of 11 patients with limited scleroderma. All scleroderma sera (33 patients' sera and 13 reference sera) were also tested for the presence of anti-Scl-70 antibodies. It was found that all anti-Scl-70 positive sera (n = 25) contained anti-Scl-86 antibody as well, suggesting a relationship between these two antigens. However, the Scl-86 antigen was shown to be an extremely insoluble nonchromosomal protein, resistant to boiling in sodium dodecyl sulfate. This contrasts with the Scl-70 antigen, which has been described as a thermolabile, soluble antigen present in the chromatin fraction. Together, our results are consistent with the idea that Scl-70 is a degradation product of Scl-86. The Scl-86 antigen is present in freshly prepared rabbit thymus, spleen, and liver nuclei as well as in nuclei from various cultured cell lines, but is not detectable in extractable nuclear antigen from rabbit thymus. In a limited retrospective study, the anti-Scl-86 antibodies were found in two sera from patients with Raynaud's phenomenon before the development of diffuse scleroderma. Therefore, it is possible that screening of patients' serum for this antibody might predict the development of diffuse scleroderma.

Animals↗
PubMed1983

Lamprey 48-kDa lens protein represents a novel class of crystallins.

SDS-PAGE revealed a major Mr 48 000 polypeptide of pI around 8 in the water-soluble fraction of lamprey lenses. It occurs as a monomeric protein, and its amino acid composition and tryptic peptides show no resemblances to alpha-, beta-, gamma- or delta-crystallin. Immunoblotting with antiserum against the 48-kDa protein revealed an immunologically related polypeptide of similar Mr in reptiles, several birds and a fish, but showed no cross-reactivity with any other water-soluble lens component. The 48-kDa protein is not detected in many birds and fishes, and in the investigated mammals and amphibians.

Amino Acids↗
PubMedDate not supplied

Ratites as oldest offshoot of avian stem--evidence from alpha-crystallin A sequences.

One of the most disputed issues in avian phylogeny is the origin of the ratites, the large flightless birds of the Southern Hemisphere (reviewed in refs 1-3). It is still not generally agreed whether the ostriches, rheas, emus and cassowaries, and probably kiwis, form a natural, monophyletic group, although much recent evidence supports this view. Also, their phylogenetic relationship with the other avian orders remains unresolved, comparative protein sequence studies might shed new light on this problem. Therefore, we determined the amino acid sequence of the eye lens protein alpha-crystallin A in ostrich, rhea and emu, and in representatives of 13 other avian orders. Comparison of these sequences with known alpha A sequences of mammals, reptiles, frog and dogfish provides strong evidence that the ratites, as a monophyletic assemblage, represent the first offshoot of the avain line.

Amino Acid Sequence↗
PubMedDate not supplied

Juvenile chronic arthritis and coeliac disease in The Netherlands.

OBJECTIVE: It has been suggested that juvenile chronic arthritis (JCA) is associated with coeliac disease in a frequency of 0.4-2%. In order to investigate the frequency of coeliac disease in cases of JCA and the possibility of underdiagnosis in our area, we screened 62 children with JCA (mean age 9.8 +/- 3.5 year) for coeliac disease. METHODS: All children were screened for coeliac disease by measuring the IgA-class of antigliadin, antireticulin and antiendomysium antibodies in serum and by measuring intestinal permeability by a sugar absorption test using lactulose and mannitol. In cases of at least one positive test, a small-bowel biopsy for diagnosis of coeliac disease was offered. RESULTS: Of the 62 children with JCA, 8 had an abnormal screening result and were suspected of having coeliac disease. In four of the five children in whom a small-bowel biopsy was performed, the intestinal mucosa was normal and in one child villous atrophy characteristic of coeliac disease was found. Therefore, the prevalence of coeliac disease in our study group was 1.5%, which is in agreement with the literature. CONCLUSION: These findings indicate no underdiagnosis of coeliac disease in JCA in our area.

Adolescent↗