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Biomedical subjects

H J Maasch

Publications and source records attributed to H J Maasch.

At least 19 recordsLinked to original sources
PubMed1992

Respiratory allergies (bronchial asthma and rhinitis) due to sensitization of type I allergy to red spider mite (Panonychus ulmi KOCH).

The inhabitants of a fruit growing area often report spontaneously of sensitization to the red spider mite (RSM) (Panonychus ulmi KOCH). These are for the most part sensitizations with low clinical symptoms (rhinitis, conjunctivitis and erythema). Severe clinical developments with bronchial asthma have been observed. We investigated six patients working in a fruit growing area sensitized by RSM. The sensitizations corresponded to a Type I allergy. Skin tests and provocation tests (nasal as well as bronchial) with RSM showed immediate reactions and RAST positive results were obtained using RSM allergen disks. RAST measurements of sera from nine house-dust mite Dermatophagoides pteronyssinus allergic patients using RSM allergen disks showed RAST-class > 1 for eight patients. RAST inhibition and immunoprint suggest a possible cross-reaction between RSM and D. pteronyssinus.

Adult↗
PubMed1991

Occupational wood-dust sensitivity from Euonymus europaeus (spindle tree) and investigation of cross reactivity between E.e. wood and Artemisia vulgaris pollen (mugwort).

A 44-year-old goldsmith suffered from rhinitis and conjunctivitis after having worked with wood dust from Euonymus europaeus (E.e.) for 15 years. The material was used for drying pieces of jewelry. Very strong reactions could be seen after friction test, scratch test and nasal challenge using wood dust of E.e. RAST-class 3 could be measured with the serum of this patient using E.e. wood and Artemisia vulgaris (A.v. pollen) allergen disks. RAST-inhibition, western-blot (WB) and immunoprint (IP) indicated common allergens in extracts of E.e. wood and A.v. pollen of different degree. In addition this study indicated that subjects suffering from A.v. pollen allergy also show sensitization to E.e. wood since in 22 of 37 A.v. pollen allergies A.v. (RAST class 2-4) IgE-antibodies could be seen. The present case probably demonstrates for the first time an IgE-mediated type I allergy to E.e. wood.

Adult↗
PubMed1990

Determination of IgE-specificities in nasal secretions and sera of allergic subjects by crossed radio-immunoelectrophoresis.

Allergen-specific IgE antibodies have not only been demonstrated in the serum, but also in the nasal secretions of allergic patients by means of the radio-allergosorbent test (RAST). In this preliminary study we adapted the technique of crossed radio-immunoelectrophoresis (CRIE) to nasal secretions in order to obtain further insight into the specificity of locally collected antibodies. Based on RAST results we compared CRIE patterns in serum, nasal secretions in 13 out of 23 grass pollen allergic subjects and two out of three house dust mite allergic subjects. In the nasal secretions the same IgE specificities were found as in the corresponding serum of the individual subject and as in a reference serum pool. These data indicate that the same specificity of IgE antibody can be found in the serum and the target organ. From these data there is no evidence for a local mucosal immune response that differs in specificity from the serum response.

Animals↗
PubMed1990

IgE-mediated allergic reactions to potatoes.

We investigated sera of 12 patients with IgE-mediated hypersensitivity reactions to potato, using different in vitro methods. Radioallergosorbent test classes 2-4 (7.6-46.5% binding) were measured with potato allergen disks. Immunoblot detected allergen bands with an isoelectric point range of approximately 4.5-5.2 and mainly in a molecular weight range between 16.00 and 30.00 kD. But also at molecular weights of 43.00 and 65.00 kD allergen bands (IgE specificities) could be detected. Histamine release assay performed with isolated fractions of the potato extract showed a great individual variation and positive results of fractions of molecular weights between 10.00 and 80.00 kD. From our data we conclude that raw potato is a 'multiallergenic' vegetable.

Adolescent↗
PubMed1990

Allergens of horse epithelium. I. Physicochemical and immunochemical characterization of five different horse epithelium raw materials used for allergen extract preparation.

We investigated five horse epithelial allergen extracts prepared from different qualities of raw material by several biochemical and immunochemical methods. Horse serum albumin and horse serum were used to identify serum-related antigens. We found high similarities as well as marked differences between the extracts. There were strong differences in the protein contents, the protein patterns obtained by isoelectric focusing and sodium dodecyl sulfate polyacrylamide gel electrophoresis, the total allergenic activities obtained by radioallergosorbent test inhibition assays and the amounts and numbers of serum-related proteins. The patterns of dander-related allergens in crossed radioimmunoelectrophoresis were similar but showed partly strong differences in allergen concentrations. Allergen compositions determined by blotting methods showed only minor differences between the investigated epithelial extracts. It appears that some of the differences, e.g. the content of serum-related proteins, depend on the way the different raw materials are prepared. Because serum-related extract components are not considered as major allergens, their content should be low in horse epithelial allergen extracts. For this reason whole skin cannot be recommended as starting material for horse epithelium allergen extract preparation.

Allergens↗
PubMed1989

Double-blind, placebo-controlled immunotherapy with mixed grass-pollen allergoids. III. Efficacy and safety of unfractionated and high-molecular-weight preparations in rhinoconjunctivitis and asthma.

Specific immunotherapy with unmodified formalinized allergoids is effective in grass-pollen allergy, but systemic reactions have been observed. A high-molecular-weight formalinized allergoid (HMW-GOID) was fractionated by gel filtration, retaining molecules of greater than 85,000 daltons in the expectation of improving safety without sacrificing efficacy. HMW-GOID and unfractionated allergoid (GOID) had a similar allergenic activity assessed by RAST inhibition, but the HMW-GOID preparation was 65 times less reactive when it was tested by skin prick test than the GOID preparation. A double-blind, placebo-controlled study was carried out in grass pollen-allergic patients with placebo (14 patients), GOID (15 patients), and HMW-GOID (13 patients). An additional group of 18 patients was treated by a rush schedule with a standardized orchard grass-pollen extract. A similar mean cumulative dose was administered with both allergoids. The fractionated allergoid only elicited minor systemic reactions similar to reactions elicited by placebo, whereas 20% of patients treated by GOID and 5.5% of patients receiving the standardized extract had a severe systemic reaction. For rhinitis, conjunctivitis, and asthma, the HMW-GOID and the standardized extract had a similar efficacy, significantly greater than placebo. GOID was less effective than the other two active treatments but was significantly more effective than placebo treatment for asthma and conjunctivitis.

Adolescent↗
PubMed1989

The international collaborative study on the first international standard of birch (Betula verrucosa)-pollen extract.

A selected candidate international standard preparation of birch (Betula verrucosa)-pollen extract was studied together with other birch-pollen extracts in a multinational study involving 20 laboratories in 11 countries. The biologic activity of the extract had previously been demonstrated in quantitative skin prick testing. The study methods comprised RAST inhibition, histamine release, quantitative immunoelectrophoresis, isoelectric focusing, and other methods. The results from RAST inhibition were calculated as parallel-line assays with statistical tests for linearity and parallelism. Analysis of variance was applied to test the significance of differences between potency estimates. In all assay methods, the candidate standard could be used to assign relative potencies to other birch-pollen extracts. The candidate standard was adequately stable during 36 months of storage at or below 5 degrees C. On the basis of this study, the World Health Organization has established the preparation as the International Standard for birch-pollen extract with assigned units of 100,000 IU per ampule.

Binding, Competitive↗
PubMed1989

Investigation of the allergenic activity of isolated fractions of a standardized partly purified whole mite body (Dermatophagoides pteronyssinus) extract.

Twelve fractions of a molecular weight range of 1.35-670.00 kilodaltons (kD) were isolated from a biologically standardized partly purified whole mite body extract (Dermatophagoides pteronyssinus) by preparative size exclusion high-performance liquid chromatography. The allergenic activity and the antigen and allergen patterns of the isolated fractions were investigated by RAST, RAST inhibition and crossed (radio)immunoelectrophoresis (CIE/CRIE). By CRIE, each of the fractions showed allergen patterns, mostly of different compositions. Each fraction showed allergenic activity of different degrees by RAST inhibition. The highest allergenic activity could be measured by RAST inhibition with fractions which contained predominantly the major allergens Der pI and PY as detected by CRIE. Also proteins of higher molecular weights (greater than 158 kD) showed IgE-binding capacities. Nearly all antigens detected by CIE could be identified as allergens using CRIE.

Allergens↗
PubMed1989

Comparison of Alternaria tenuis extracts prepared from different raw materials.

Alternaria extracts, prepared from three different sources under the same conditions, were compared by several biochemical/immunochemical methods. Two raw materials (A,G) contained mostly mycelia. The third raw material (C) contained mycelia (35%) and spores (65%). Extracts A and G were different in total allergenic potency, antigen/allergen pattern, and in the Alt 1 content. Extract C was of similar total allergenic potency as extract A but showed a somewhat different antigen/allergen pattern and a different Alt 1 content. Although there were some compositional differences among the extracts, all extracts regardless of source materials (spores and mycelia) demonstrated strong RAST inhibition activity and parallelism of the inhibition curves.

Allergens↗
PubMed1988

Investigations of patients allergic to the house dust mite Dermatophagoides pteronyssinus by crossed radioimmunoelectrophoresis using purified mite bodies and whole mite culture extracts.

Sera of 20 patients allergic to the house dust mite Dermatophagoides pteronyssinus were investigated by crossed radioimmunoelectrophoresis (CRIE) using extracts prepared from purified mite bodies (PMB) and whole mite culture (WMC). By CRIE, different allergen patterns and different numbers of allergens were detected in the two extracts. By summarizing the values of the CRIE patterns of the 20 patients' sera into allergograms, 6 out of 16 allergens in PMB and 5 out of 10 allergens in WMC extracts could be identified as major allergens. These diverging results, together with the published literature, emphasize the necessity to reevaluate the International Standard for D. pteronyssinus.

Allergens↗
PubMed1987

Molecular weight determination of allergen extracts and isolation of allergenic molecules by high-performance liquid chromatography.

The usefulness of size-exclusion high-performance liquid chromatography (HPLC) for the molecular weight determination of allergen extracts as a method of process control was investigated by measuring seven different batches of timothy pollen extracts. Preparative HPLC was used for the isolation of the major allergen Cat 1, from a crude cat hair and skin scraping (CHSS) extract. The chromatograms of the seven batches of the timothy pollen extracts looked very similar, suggesting the same molecular weight distribution in each extract. The major allergen, Cat 1, could be isolated from the crude CHSS extract by preparative HPLC in acceptable purity, determined by crossed radioimmunoelectrophoresis.

Allergens↗
PubMed1987

Double-blind, placebo-controlled immunotherapy with mixed grass-pollen allergoids. I. Rush immunotherapy with allergoids and standardized orchard grass-pollen extract.

Forty-five grass pollen-allergic patients were randomly assigned to three groups according to their skin test and RAST sensitivities and the severity of seasonal rhinitis. Eleven patients were treated with placebo (group 1), 19 patients (group 2) were treated with a six-mixed grass-pollen allergoid prepared by mild formalinization with a two-step procedure, and 15 other patients were treated with a standardized orchard grass-pollen extract (group 3). Because of a different immunotherapy schedule, only patients placed in groups 1 and 2 received the extracts in a double-blind fashion. Rush immunotherapy was performed in 3 to 6 days, and the maintenance dose was subsequently administered weekly for 4 weeks and every 2 weeks until the end of the grass-pollen season. During the season, a coseasonal treatment was administered. Systemic reactions occurred during the rush protocol in 36.8% of patients treated with allergoid and 20% of patients who received the standardized extract. Only patients treated with allergoid had systemic reactions during maintenance dose. The reactions observed with the standardized extract were more severe. Total doses of allergoid ranged from 2350 to 13,500 protein nitrogen units. Symptoms and medication scores during the peak of the season were analyzed. Patients treated with the standardized allergen had a significant reduction of the number of days of symptoms during the month of June (9.5 +/- 6.7 days; p less than 0.005) and of medication scores (1.3 +/- 1.4; p less than 0.01) compared to patients receiving placebo (19.4 +/- 8.1 days; medication score, 2.8 +/- 2.1).(ABSTRACT TRUNCATED AT 250 WORDS)

Allergens↗
PubMed1987

Double-blind, placebo-controlled immunotherapy with a high-molecular-weight, formalinized allergoid in grass pollen allergy.

Specific immunotherapy is effective in grass pollen allergy with standardized extracts and formalinized allergoids; but systemic reactions are not uncommon. A high-molecular-weight (greater than 85,000 daltons), formalinized allergoid was investigated in a double-blind, placebo-controlled study to assess its safety and efficacy. Twenty patients received a placebo and 39 the allergoid using a rather aggressive protocol. Five patients developed a mild and transient systemic reaction with high doses of allergoid and one had a more severe reaction requiring treatment. Nasal challenges performed with orchard grass pollen grains showed that the threshold number of grains eliciting nasal symptoms was significantly (p less than 0.01) greater in the treated group. This group had significantly (p less than 0.01) less nasal symptoms during the season and specific IgG levels were significantly (p less than 0.01) elevated. There was a significant (p less than 0.01) correlation between nasal challenges and nasal symptoms during the season but no correlation between IgG and symptoms. There was no dose-dependent effect of allergoids.

Adolescent↗
PubMed1987

Application of the first international standard of Dermatophagoides pteronyssinus (house dust mite) in the evaluation of allergen extracts produced from two different source materials.

The first international standard (IS) of the house dust mite Dermatophagoides pteronyssinus was used to compare side-by-side two allergen extracts prepared from two different house dust mite sources, namely whole mite cultures (WMC) and purified mite bodies (PMB), by employing several biochemical and immunochemical methods. In most methods employed, IS and WMC resembled more to each other than to PMB. These similarities comprehend protein contents, protein patterns, antigen and allergen patterns as well as total in vitro activity obtained in RAST inhibition (RI). The differences between WMC and PMB could be reproduced in different batches. Standardization in relation to IS of D. pteronyssinus yields activity ratios ranging from 2.4 to 70.1 between WMC and PMB depending on the variation of RI employed, indicating quantitative differences between the two preparations. When coupled to BrCN activated paper disks and employed in direct RAST, both preparations yielded almost identical binding values of specific IgE. Also in skin prick test, WMC and PMB produced very similar results in 12 mite-allergic patients. It was not possible to differentiate between the two preparations when used in concentrations which are usually employed for diagnostic purposes. These findings demonstrate the diversity of allergens in mite extracts derived from different sources and reveal the problems which are involved with the use of the WHO D. pteronyssinus IS.

Allergens↗
PubMed1987

Allergenic activity of short ragweed pollen (Ambrosia elatior) from different years and/or suppliers: criteria for the selection of an in-house allergen reference preparation.

We have investigated dialyzed extracts (A-F) of short ragweed pollens (Ambrosia elatior) from six consecutive production years and four different companies by protein nitrogen units, high performance liquid chromatography, isoelectric focusing, SDS-PAGE, RAST inhibition, crossed radioimmunoelectrophoresis, and antigen E contents. Extract A showed lowest yields in all quantitative assays. Isoelectric focusing, SDS-PAGE, crossed immunoelectrophoresis, and crossed radioimmunoelectrophoresis showed comparable patterns for all extracts except for extract A. Apparently, the activity of short ragweed pollens depends on the year of production and/or the skill of the producer. These findings are in contrast to similar examinations of other pollen species.

Allergens↗