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Biomedical subjects

A Koivikko

Publications and source records attributed to A Koivikko.

At least 37 records · Page 2Linked to original sources

Distribution of watersoluble antigens and allergens of Candida albicans in blastospore cell extract fractions.

Watersoluble antigens of Candida albicans were sequentially extracted from intact and disrupted yeast cells grown on protein-free agar, and analysed on immunoblots after SDS-PAGE. Washing of the cells in saline before proper extraction resulted in loss of 47.2% of the total carbohydrate and 1.5% of the total protein. The protein fraction contained 14 antigenic bands when analysed with hyperimmune rabbit antisera. Four of these bound IgE when probed with a RAST-positive serum pool and beta-galactosidase-labelled anti-IgE. Extraction of the disrupted cells resulted in 15% of the total carbohydrate and 94% of the total protein. The cytoplasmic protein fraction showed 69 antigenic bands, 13 of which bound IgE. The carbohydrate fraction contained mannan, which was found in the washing solutions and in the surface extract as well as in the cytoplasmic extract. Allergens found in washing solutions were also present in cytoplasmic fraction. This study suggests that the rapid release of allergens from saprophytic C. albicans cells on mucous membranes of the body may cause continuous exposure and result in sensitization.

Allergens↗

IgE-, IgA- and IgG-antibody responses to carbohydrate and protein antigens of Candida albicans in asthmatic children.

Analysis of IgE, IgA and IgG antibodies directed against Candida albicans antigens in 28 asthmatic children was performed with immunoblotting after SDS-PAGE. Analysis with the purified cytoplasmic protein fraction revealed a major protein allergen with an MW of 46 kD. In addition to the major allergen, 15 other antigenic bands with molecular weights between 16 and 135 kD bound IgE. Ten of 13 anti-C. albicans IgE-positive children had IgE towards the 46 kD major allergen. None of the subjects in the study group or in the non-atopic controls had IgA or IgG antibodies towards this protein. Analysis of the crude surface extract showed that mannan, a carbohydrate, was an intermediate allergen contrary to being the major antigen in IgA and IgG antibody responses.

Adolescent↗

Circulating immune complexes during immunotherapy in allergy to dog.

Circulating immune complexes (CIC) were determined from dog-allergic asthmatic children (n = 35) receiving immunotherapy with dog dander and hair extract. The results from CIC are expressed in SDU (standard deviation units) and presented as follows: pretreatment results (n = 20), rush results (n = 11), mid-schedule results (n = 20), maintenance results (n = 15) and the results of the placebo-treated group (n = 12). The results of the placebo-treated group (n = 12) and those of the untreated atopic (n = 12) and non-atopic (n = 14) were controls. CIC levels were analysed by means of KgB-ELISA (conglutinin binding enzyme linked immunosorbent assay), C1qB-ELISA (C1q-binding enzyme linked immunososrbent assay), RFb-ELISA (rheumatoid factor binding enzyme linked immunosorbent assay) and by PIPA (platelet 125J-labelled staphylococcal protein-A test). The CIC level determined by KgB-ELISA in dog-allergic asthmatic children was higher than that of the atopic controls (P less than 0.05) already before the onset of the hyposensitization. During conventional hyposensitization with dog dander and hair the CIC level remained the same as before treatment. On day 5 of rush hyposensitization the mean level of CIC showed no increase when compared with the pretreatment values. A statistically significant correlation (P less than 0.01) was observed between the dog dander and hair-specific IgG antibodies and the CIC level measured by KgB-ELISA during the maintenance period of conventional immunotherapy. The samples of sera to measure this correlation were collected before the injection of allergen and after 2 weeks of injection during maintenance treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Reproducibility of the skin prick test.

Reproducibility of the skin prick method of testing for allergy was studied in 20 subjects examined by four nurses. Hypodermic needles were used for pricking and the test panel included a histamine control, a diluent control, and nine allergens. The reproducibility of the method was best when the size of the weal reaction caused by an allergen was expressed as the geometric area of the weal. When the weal reaction was expressed as the ratio of the weal reaction caused by an allergen to that caused by histamine, the reproducibility of the method was decreased considerably. When the ratios were further classified into three class ratings, reproducibility was very low. The reduction in reproducibility was due to the low reproducibility of histamine reactions. According to these results, at least in epidemiological studies the weal reactions should be expressed as geometric areas. In clinical practice it might also be preferable to express prick test results as the diameters of the weals without adjusting them by histamine reactions.

Allergens↗

Allergenic variability of different strains of Candida albicans.

The allergenic variation of six Candida albicans strains was studied by immunoblotting with pooled sera from 20 C. albicans-RAST-positive subjects. The presence of a 46-kilodalton (kD) protein, the major allergen, and a 29-kD protein, an intermediate allergen, was shown in crude extracts from disrupted cells (six strains). There was a significant variation in the content of the major C. albicans allergen (46 kD) between the different strains. Surface extracts of all six C. albicans strains contained mannan. Immunoblotting of cell wall extracts of intact C. albicans (agar plate) of different age revealed the strongest IgE binding in cultures incubated for 36-50 h. Due to the varying proportions of allergens demonstrated in the different strains of C. albicans, the starting source material for extract production should be a pool of individual strains, which all should be analysed prior to pooling. Special attention should be paid to the selection of C. albicans strains, and a parameter such as the breakability of the strain should be considered.

Allergens↗

Allergenic cross-reactivity of yeasts.

Yeast allergen extracts of Candida albicans, C. pseudotropicalis, C. krusei, C. parapsilosis, C. tropicalis, C. guilliermondi, C. humicola, C. norwegica, C. utilis, Cryptococcus albidus, Geotrichum candidum, Pityrosporon pachydermatis, P. ovale, Rhodotorula minuta, R. rubra, Saccharomyces cerevisiae, Torulopsis glabrata and Trichosporon cutaneum were investigated regarding their common allergenic properties. The enzyme immunoassay (EIA) using rabbit anti-Candida albicans antiserum showed remarkable immunological cross-reactivity only between the Candida species. However, there was a significant multiple sensitivity to the extracts of C. albicans, C. utilis, Cr. albidus, R. rubra and S. cerevisiae in skin prick testing in atopic patients, suggesting the possible presence of one or more common skin reactive allergens.

Allergens↗

Relationship of immediate and delayed hypersensitivity to nasopharyngeal and intestinal growth of Candida albicans in allergic subjects.

The growth of C. albicans yeast in the nasopharynx and in the anus as well as allergy symptoms were followed up for 8 months in 67 patients with bronchial asthma, allergic rhinitis and/or atopic eczema. 38 of the patients were skin prick test positive and 29 negative to C. albicans allergen extract. 32 of the patients had positive and 19 negative delayed skin reactions. The nasal, bronchial and skin symptoms of the yeast-sensitive allergic patients were not associated with the nasopharyngeal nor anal occurrence of C. albicans or other yeasts. The use of nasal or inhaled steroids had no effect on the occurrence of Candida in the nasopharynx. It was observed that immediate skin sensitivity had a positive correlation and the delayed sensitivity a negative correlation with the occurrence of C. albicans growth in nasopharynx and anus. These findings are in agreement with the concept that impaired cell-mediated immunity to C. albicans may lead to increased IgE response. This may explain the increased liability towards C. albicans nasopharyngeal and gastrointestinal "saprophytic" growth.

Adult↗

Mushroom allergy.

The overall extent of mushroom allergy is not known. It may be very slight (1%) from eating, but could, alternatively, be as prevalent as pollen and mould allergy (10-30% of an allergic population). Aerospora of mushrooms and other woodland fungi, mostly basidiospores, occur in temperature zones in June to November, reaching maximum in August and September in quantities comparable to pollen and mould spores. There are large local and annual variations in species and spore concentrations in different milieus. In SPT and BPT studies about two dozen of these species have been associated with inhalant type I allergy. All species studied so far have yielded positive results. Mushroom allergens have been explored in only two studies. These show that mushrooms are antigenically rich and that a species can have more than one allergen. The difficulties of mushroom allergen research are very substantial because one usually has to rely on naturally growing mushrooms, where allergenic contamination by other allergen sources is frequent. Choice and recognition of species is also difficult. Virtually all known allergenic mushrooms and fungi are universal, growing equally well in Europe and North America. The genus Chlorophyllum occurs only in North America, but its close relatives of the genus Macrolepiota are common also in Europe. Podaxis grows only in desert regions near the equator and is not found in Europe. The majority of the large and more common universal mushroom families has not yet been investigated. The allergenicity of families Cortinariaceae, Russulaceae, Lactariaceae and Boletaceae is totally obscure even though they produce large quantities of spores in the air, particularly in northern Europe.

Allergens↗

Leukocyte migration inhibition test in children with cow milk allergy.

The usefulness of the leukocyte migration inhibition factor (LIF) test to detect cow milk (CM) hypersensitivity was studied in 40 children with suspected allergy to CM. Hypersensitivity was carefully investigated by oral milk challenges, which gave a final confirmation of cow milk hypersensitivity in 12 subjects, and excluded it in the remaining 28 subjects. Leukocyte migration inhibition was measured using beta-lactoglobulin (BLG), alpha-lactalbumin (ALA), alpha-casein (ACA) and bovine serum albumin (BSA) as antigens. IgA and IgG antibodies to these antigens were measured by an enzyme-linked immunosorbent assay, and IgE antibodies to these antigens and to CM by radioallergosorbent test (RAST). Skin prick test with CM was performed in 38 subjects, and with BLG, ALA, ACA and BSA in 29 subjects. Leukocyte migration was more often inhibited by cow milk antigens in the CM challenge positive (CM+) subjects than in the challenge negative (CM-) subjects. Of the specific milk antigens, ALA was the most potent inhibitor, and gave a positive LIF test result in all CM+ subjects, and significantly (P less than 0.02) less often (15/24) in CM- subjects. Also in the skin prick test and RAST, ALA gave positive results more often than the other milk antigens. BLG, ACA and BSA had an inhibiting effect on leukocyte migration, but the difference between the CM+ and CM- subjects was not statistically significant. Two of the 12 CM+ subjects had no demonstrable IgE antibodies to CM proteins; both of them, however, had a positive LIF test with at least one of the CM antigens.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

A sandwich enzyme immunoassay for the detection of human IgG antibodies to dog allergens.

A double-sandwich enzyme immunoassay (DSEIA) was developed for the detection of human IgG antibodies to dog dander and hair (DH) allergens. Since DH allergens are immunogenic in rabbits, the gamma-globulin fraction of rabbit antiserum to DH (RGG-a-DH; 10 micrograms/ml) was used for coating of polystyrene microtiter plates. Dog allergens (1 microgram/ml of DH extract) were bound to RGG-a-DH. Binding of human IgG Ab to nonimmune RGG (10 micrograms/ml)--used as a background control--was substracted from the DH specific one and nonspecific binding was further eliminated by using 0.5% of normal rabbit serum in the dilution buffer. Sera were diluted 1:10 in this buffer. Specificity of the assay was shown by absorption experiments: protein A, anti-IgE discs (Phadebas PRIST) and dog or birch (e5, t3; Phadebas RAST) allergen discs were used to remove total and allergen specific IgG and IgE, respectively. The results were expressed as net absorbances or as a percentage of a reference serum. A significant correlation (r = 0.65, p less than 0.001) between IgG (DSEIA) and IgE (RAST) antibodies to dog allergens was observed in 40 untreated dog allergic subjects. The DSEIA was found to be more sensitive than conventional ELISA in detecting IgG Ab in 15 asthmatic children during hyposensitization: a significant rise was observed in 14 compared to 12 with ELISA, while no significant increases were observed in the placebo-treated group.

Adolescent↗

Efficiency of a new bioaerosol sampler in sampling Betula pollen for antigen analyses.

A new bioaerosol sampler consisting of Liu-type atmospheric aerosol sampling inlet, coarse particle inertial impactor, two-stage high-efficiency virtual impactor (aerodynamic particle sizes respectively in diameter: greater than or equal to 8 microns, 8-2.5 microns, and 2.5 microns; sampling on filters) and a liquid-cooled condenser was designed, fabricated and field-tested in sampling birch (Betula) pollen grains and smaller particles containing Betula antigens. Both microscopical (pollen counts) and immunochemical (enzyme-linked immunosorbent assay) analyses of each stage were carried out. The new sampler was significantly more efficient than Burkard trap e.g. in sampling particles of Betula pollen size (ca. 25 microns in diameter). This was prominent during pollen peak periods (e.g. May 19th, 1985, in the virtual impactor 9482 and in the Burkard trap 2540 Betula p.g. X m-3 of air). Betula antigens were detected also in filter stages where no intact pollen grains were found; in the condenser unit the antigen concentrations instead were very low.

Aerosols↗

A double-blind, multicenter immunotherapy trial in children, using a purified and standardized Cladosporium herbarum preparation. I. Clinical results.

A double-blind histamine placebo controlled immunotherapy trial was performed to investigate the clinical effect of a purified and standardized Cladosporium herbarum allergen preparation. Thirty children with a clinical history suggesting mould-induced asthma and/or rhinoconjunctivitis were included. The diagnosis was confirmed by positive skin prick test and Phadebas RAST as well as positive bronchial and/or conjunctival provocation test to Cladosporium herbarum. Immunotherapy was given for 10 months in a double-blind manner to randomized groups with either Pharmalgen/Cladosporium herbarum preparation or histamine placebo. Allergic side effects to injections were common, especially during the peak of the mould season (July-September in Scandinavia). In the active group, 13/16 patients experienced general reactions during the first 10 months of treatment. After 6 months of treatment, eye, nose and bronchial symptom scores and peak expiratory flow rates were similar for the groups, maybe because most of the children were also sensitive to many other allergens, including Alternaria alternata. However, medication scores were significantly lower in the treated group (P less than 0.01). Bronchial (P less than 0.01) and conjunctival sensitivity (P = 0.01) were significantly reduced in the Cladosporium-treated group but not in the placebo group after 10 months of treatment. This is the first double-blind clinical trial showing the clinical efficacy of immunotherapy in children with mould-induced asthma.

Adolescent↗

A double-blind, multicenter immunotherapy trial in children, using a purified and standardized Cladosporium herbarum preparation. II. In vitro results.

This double-blind immunotherapy trial in children, using a purified and standardized Cladosporium herbarum allergen preparation, has shown that children with mould asthma and/or rhinoconjunctivitis, responded to immunotherapy with a decrease in specific IgE and a significant increase in specific IgG. There was a marked increase in the ratio specific IgG/specific IgE as a result of active treatment. IgE-CRIE radiostaining patterns showed no pronounced changes after 10 months' active treatment and no "new sensitivities" could be detected in the studied patients. IgG-CRIE radiostaining, primarily directed towards the important allergens, was significantly increased in the active group and particularly towards Ag-12 (partially identical to a previously described major allergen in Cladosporium herbarum, Ag-54). Children treated with histamine placebo showed no change in antibody patterns during 10 months of treatment.

Adolescent↗

Pollen seasons: forecasts of the most important allergenic plants in Finland.

Occurrence of airborne pollen in Finland has been studied for 10 years in Turku (southern Finland), 8 years in Oulu, 4 years in Kuopio (central Finland) and 7 years at Kevo (northern Lapland). Observations on the pollen seasons of alder, birch, grasses and mugwort are presented. All these pollens occur in south and mid- Finland in quantities capable of causing allergy symptoms. Except for birch pollen, allergenic pollens occur in far lower concentrations than in central Europe. In northern Lapland only birch and pine pollen concentrations are high. Pollens may occur without signs of local flowering when there are southerly winds. This finding suggests that long-distance transport is an essential contributing factor to the occurrence of pollens. There are wide year-to-year variations in the start of pollen seasons and the quantities of pollens. The variations in the start of birch and grass pollen seasons could very much depend on the mean temperature in April. However, a forecasting model based on this and other spring-time temperature parameters often fails to give sufficiently accurate forecasts.

Finland↗

Immunotherapy in allergy to dog. Immunologic and clinical findings of a double-blind study.

Twenty-seven dog-allergic asthmatic children with no pets in the home were included in the study. The clinical trial was performed as a double-blind study using a commercial standardized aluminum hydroxide-bound dog dander and hair extract or histamine-placebo. The patients were randomized into the active treatment or the placebo group on the basis of the RAST (e5) and the provocation test with aqueous dog dander and hair extract. The good clinical response of immunotherapy with dog dander and hair extract has been reported earlier. The specific immunotherapy resulted in an increase in the serum level of antigen-specific IgG antibodies (P less than .01) and a decrease in the skin sensitivity to dog extract (P less than .001) in the active treatment group when compared with the placebo group. The treatment was well-tolerated. No systemic reactions occurred and local reactions were mild. The results show a good immunologic response with a standardized dog dander and hair extract. There were no major changes in the course of bronchial asthma in either group. After 1 year of immunotherapy the subjects had no symptoms on a dog-exposure of short duration. This must be carefully emphasized when considering the indications for immunotherapy.

Adolescent↗

Diagnosis and immunotherapy of mould allergy. I. Screening for mould allergy.

In order to screen for mould allergy, extracts of five common atmospheric moulds (Cladosporium, Alternaria, Penicillium, Aspergillus and Mucor) from various manufacturers were investigated in 130 patients (5-60 years old) with clinical symptoms indicating possible mould allergy. The patients were screened by skin prick test (SPT) and radioallergosorbent test (RAST). SPT seemed to be more sensitive than RAST as a diagnostic screening procedure (80% positive reactions to one or more species compared to 50%). With a partially purified, standardized preparation of Cladosporium herbarum more positive reactions were obtained than with crude extracts without evidence of any unspecific reactions. The difference between commercial and standardized extracts is most probably a result of a variation of both the biological potency of allergenic determinants and the allergenic composition. A considerable number of negative RAST reactions with standard discs were found in patients with positive skin reactions to partially purified Cladosporium, but RAST seemed to be more sensitive than SPT with the other commercial mould extracts. Based on the screening, a very convincing tendency to IgE-reactivity to other moulds was found in patients reacting to Cladosporium, the most common cause of mould allergy. The results confirm the inadequacy of most mould extracts used in diagnostic procedures and strengthen the value of using standardized extracts.

Adolescent↗