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PubMed1984

Rhinitis in the athlete.

Trauma is the most common problem involving the nose in sports and athletic events. Injury may lead to "vasomotor syndrome" and chronic rhinitis. Nasal and sinus obstruction may cause additional discomfort. Exposure to irritants, particularly solvents, cleaning solutions, paints, and varnishes as well as air pollutants exacerbates vasomotor rhinitis. Allergic rhinitis is another major problem of atopic athletes. It may be caused by exposure to pollens, molds, dust, or animal danders. Treatment is aimed at reducing the exposure to etiologic factors as well as pharmacologic management. Antihistamines, topical cromolyn, and topical steroids may be used to control rhinitis without violating " antidoping " regulations.

Allergens↗

PubMed1986

Studies on bronchial hyperreactivity, allergic responsiveness, and asthma in rural and urban children of the highlands of Papua New Guinea.

The prevalence of asthma and allergic responsiveness in rural and urban children of the highlands of Papua New Guinea was studied. Bronchial provocation studies with histamine demonstrated significant bronchial hyperreactivity in 0.5% (1 in 195) rural and 1.7% (1 in 59) urban children, rates which were significantly lower than those observed in corresponding adult populations (7%). Urban children demonstrated a higher incidence of skin test reactivity toward Dermatophagoides pteronyssinus, Aspergillus fumigatus, and dog dander than did the rural children. However, there were no significant differences between these populations with regard to total serum IgE levels, the degree of parasitism as judged by stool examination, or allergic responses to Ascaris suum, plantain, and coffee bean husk. A more detailed study demonstrated age- and sex-related differences in total IgE and mite-specific RAST scores in the rural but not the urban population. These data suggest an active suppression of the capacity of children to mount an IgE response to environmental allergens such as the mite manifesting itself as low asthma prevalence. The data also indicate that, although the underlying defect of bronchial hyperreactivity in asthma may be genetically inherited, it is not revealed until the lung has received an allergen-induced inflammatory insult.

Adolescent↗

PubMed1988

Comparison between modified skin prick test with standardized allergen extracts and Phazet.

Skin prick tests (SPTs) represent one of the most common techniques of skin testing and are of great value, especially when standardized extracts are used. Phazet is a puncture test involving needles coated with standardized allergens. Phazet and SPTs have been compared in 130 subjects tested with six standardized allergen extracts: orchard-grass, olive, and mugwort pollens, cat dander, Dermatophagoides pteronyssinus, and Alternaria. Patients have been carefully selected on the basis of a suggestive clinical history, SPTs, and RAST. For all allergenic species, at least 20 nonsensitive individuals have been tested. The sensitivity (true positive in percent of patients with disease) of Phazet was 99.4%, and its specificity (true negative in percent of patients without disease) was 99.2%. It is concluded that Phazet and SPTs with standardized extracts are equally effective in the diagnosis of immediate-type allergy and that standardized extracts have improved the diagnosis of allergy, especially for previously poorly characterized extracts, such as Alternaria.

Adolescent↗

PubMed1988

Immunotherapy for cat asthma.

In 22 patients with cat asthma who were highly sensitive to cat, we compared, double-blind, the effects of immunotherapy with cat-hair and dander extract (11 patients) with effects of placebo (11 patients). Patients were matched by the dose of the cat extract expressed in Food and Drug Administration (FDA) units of Fel d I (previously called cat allergen 1) required for end point reaction in intradermal skin test end point titration (STEPT), for in vitro leukocyte histamine release (LHR), and for the dose of cat extract producing a 20% fall in FEV1 (cat-extract PD20) in bronchoprovocation test. Patients were matched also for bronchoprovocation dose of methacholine producing a 20% fall in FEV1 (methacholine PD20). Patients were randomly assigned to one of two treatment groups. During immunotherapy, doses were increased to maintenance dose of 4.56 FDA units of Fel d I, or, if this were less, to the highest tolerated dose. Systemic reactions to cat-extract immunotherapy were mild and infrequent. Before and during immunotherapy, we measured (in FDA units of Fel d I) cat-extract PD20, cat-extract intradermal STEPT, cat-extract in vitro LHR, serum levels of cat IgG and cat IgE, and methacholine PD20. After they had received 1 year of immunotherapy, patients receiving cat extract, in comparison to patients receiving placebo, had decreased cat-extract PD20 (p less than 0.01), diminished responses to cat-extract intradermal STEPT (p less than 0.025), increased IgE antibodies toward cat extract (p less than 0.01), increased IgG antibodies toward cat extract, Fel d I, and cat albumin (p less than 0.001), but no significant change in cat-extract in vitro LHR or in methacholine PD20. We conclude that cat-extract immunotherapy was well tolerated, significantly decreased skin and bronchial responses to cat extract, and significantly increased IgE antibodies to cat extract and IgG antibodies to cat extract, Fel d I, and cat albumin.

Adult↗

PubMed1988

Atopic dermatitis and aeroallergen contact sensitivity.

Atopic dermatitis (AD) may be worsened by ingested foods or contact with irritants. We have identified 10 patients (six male and four female subjects, aged 1 to 54 years) with AD and contact sensitivity to a variety of aeroallergens. Marked improvement in skin symptomatology was noted when these patients were removed from their usual environment. The patients had markedly positive immediate wheal-and-flare reactions to a variety of aeroallergen extracts in response to prick tests and were subsequently patch tested on uninvolved skin with aeroallergen extracts (1:20 wt/vol, 50% glycerine) that elicited positive prick tests. Patch tests were applied for 48 hours, removed, and then were interpreted 24 hours later. Fifty percent glycerine was used as a negative control. Significant delayed cutaneous responses to a variety of aeroallergens were noted: house dust mite, tree, grass and weed pollens, animal danders, and various molds. Positive delayed cutaneous responses correlated strongly with aeroallergens identified in the patient's environment and/or suspected by the patients as provocateurs of their AD. Delayed cutaneous reactions were negative to aeroallergens not historically relevant to their AD. We conclude that aeroallergen contact may play an important role in selected patients with AD. The demonstration of immediate and delayed cutaneous responses in AD suggests both IgE and cell-mediated hypersensitivity as contributory mechanisms.

Adolescent↗

PubMed1989

Epidemiology of acute asthma: IgE antibodies to common inhalant allergens as a risk factor for emergency room visits.

In recent years the morbidity and mortality of asthma has increased, although the etiology is still poorly understood. Most patients with asthma suffer acute attacks that are commonly treated in hospital emergency rooms (ER). In the present study, asthma in adults was studied with acute attacks as a marker for the disease; 102 patients first observed at a university hospital ER with acute airway obstruction were compared to 118 patients observed at the same ER with any diagnosis other than shortness of breath to evaluate allergy as a risk factor for asthma in adults. Sera were assayed for IgE antibody (Ab) to dust mites, cockroach, cat dander, and grass and ragweed pollen. The results demonstrate that in adults younger than 50 years of age, the prevalence of IgE Abs was fourfold greater among subjects with asthma than among control subjects (46/67 versus 12/81; odds ratio, 10.1; 95% confidence interval, 4.9 to 20.7). The population attributable risk for the presence of IgE Ab to one of the five allergens was greater than 50%. Among individuals older than 50 years of age, the prevalence of serum IgE Abs was not significantly increased among patients with acute airway obstruction. In the whole group, the prevalence of IgE Abs to different allergens demonstrated significant seasonal and socioeconomic differences, suggesting that the associated risk is related to exposure to those allergens. The results establish that, with acute attacks of asthma as a marker for adult asthma, the presence of serum IgE Abs to common inhalant allergens is a major risk factor.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1989

Immunotherapy decreases skin sensitivity to cat extract.

In 22 patients with cat asthma who were highly sensitive to cat, we compared, double-blind, the effects of immunotherapy with cat-hair and dander extract (11 patients) with effects of placebo (11 patients). Patients matched by intradermal skin test titration, leukocyte histamine release, and the doses of both cat extract and methacholine required for 20% fall in FEV1 were randomly assigned to one of the two treatment groups. Immunotherapy doses were increased to a maintenance dose of 4.56 Food and Drug Administration (FDA) units of Fel d I or if maintenance dose was less, to the highest tolerated dose. Before and during immunotherapy, we measured by intradermal titration the dose of cat extract, in FDA units of Fel d I equivalents, required for (1) 2+ end point (wheal diameter, greater than or equal to 10 mm; erythema diameter, 20 to 30 mm) and (2) 20 mm end point (erythema diameter, 20 mm). By prick skin test, we measured (1) the dose of cat extract that produced a wheal equal in area to that produced by histamine, 1 mg/ml, (2) the doses of cat extract that produced a wheal 22 mm2 in area, and (3) the sum of the wheal areas produced by five prick tests to 23.8, 7.1, 2.4, 0.7, and 0.2 FDA units per milliliter of Fel d I, respectively. After 1 year of treatment, in comparison to control patients, treated patients had significant increases in the ratio 1 year value/pretreatment value for the doses of cat extract required for intradermal test end points 1 and 2 (p less than 0.01), for prick test end point 1 (p less than 0.01), for end point 2 (p = 0.015), and significant decreases in this ratio for prick test end point 3 (p = 0.015). Treated patients also had significant increases in cat extract required for a 20% fall in FEV1 (p less than 0.01), in IgG antibodies toward whole cat extract, Fel d I and cat albumin (p less than 0.001), and in IgE antibodies toward whole cat extract, (p less than 0.01). Thus, a decrease in skin sensitivity to cat extract demonstrated by both intradermal and prick methods occurred in patients after 1 year of immunotherapy with cat extract at a time when bronchial sensitivity to cat extract was decreased and IgG and IgE antibodies toward cat extract were increased.

Allergens↗

PubMed1990

Inflammatory mediator release on conjunctival provocation of allergic subjects with allergen.

To evaluate the role of inflammatory mediators in the pathogenesis of the ocular allergic response, 23 subjects with positive histories of allergies to either cat dander or ragweed pollen and positive skin tests to the appropriate allergen extract were recruited and were subjected to conjunctival provocation. The tear duct of the left eye of each subject was blocked with a collagen plug while the right eye was left unplugged. In all cases, the eye was initially provoked with saline and subsequently with the appropriate allergen extract. Nonallergic subjects, or allergic subjects provoked with nonrelevant allergen, were used as control subjects. After each provocation, symptoms were recorded, and tears were collected with preweighed strips of filter paper (Schirmer strip). Each strip was placed into a tared tube containing fluid appropriate for the optimal preservation of the mediator to be measured. It was therefore possible to calculate the weight of tears collected and to express mediator levels per milliliter of tears. All allergic subjects demonstrated a positive symptomatic response to allergen challenge, whereas the control subjects remained asymptomatic. Blockage of the tear duct did not significantly alter the response. For allergic subjects, the levels of histamine, kinins, prostaglandin D2, albumin, and TAME-esterase activity were all significantly (p less than 0.005 in each case) greater after allergen challenge than after saline challenge. Furthermore, levels of each of these mediators after allergen challenge (expressed as increases above levels after saline provocation) were significantly greater for allergic subjects than for control subjects (p less than 0.005 in each case). Thus, the clinical response to conjunctival provocation with allergen is associated with increases in the levels of inflammatory mediators in tears.

Adolescent↗

PubMed1990

Allergy in subjects with asthma from childhood to adulthood.

We studied the change from childhood to adulthood in skin test reactivity to house dust, animal dander, grass pollen, and molds, and, in addition, the change in number of blood eosinophils. The study was carried out in a group of 119 children with asthma, aged 6 to 14 years first observed between 1966 and 1969. In the present study, 101 subjects (85%) were reinvestigated after a mean period of 16 years; 43% had current symptoms. Skin test reactivity to all allergens and the number of subjects with positive skin tests to more than one allergen increased from childhood to adulthood. Subjects with allergic rhinitis (38%) had a higher number of positive skin tests to grass pollen in both childhood and adulthood than subjects without allergic rhinitis. Fifty-three children and 10 adults had atopic dermatitis. Atopic dermatitis occurred with equal frequency in children who did and in children who did not have current symptoms later in life. No differences in skin test reactivity to allergens were found between smoking and nonsmoking subjects. Although the smoking period was relatively short, smoking was correlated with eosinophilia in adulthood. The mean number of eosinophils decreased significantly between the first and second survey. The outcome of childhood asthma as defined by current symptoms was not predicted by skin reactivity to allergens, eosinophilia, atopic dermatitis, or allergic rhinitis in childhood.

Adolescent↗

PubMed1991

Assay for the major dog allergen, Can f I: investigation of house dust samples and commercial dog extracts.

Monospecific rabbit antibodies were used to develop a sensitive two-site enzyme immunoassay to measure a major dog hair and dander allergen, Can f I. This Can f I assay demonstrated no reaction with 17 heterologous allergen sources, including dog albumin, cat, guinea pig, and horse. Analysis of serial dilutions of purified Can f I and the international standard for dog was parallel. The assay was considered specific for Can f I with a lower limit of detection at 0.03 micrograms/ml. Total imprecision was from 2% to 6%. Commercial dog extracts for specific immunotherapy contained from 0.7 to 290 micrograms of Can f I per milliliter. The assay was used to measure Can f I in 136 house dust samples collected from 103 homes across the United States. Concentration of the dog allergen was expressed as micrograms of Can f I per gram of dust. Prevalence of Can f I in the dust samples ranged from less than 0.3 to 10,000 micrograms/gm. Serial dilutions of samples containing Can f I were parallel to the standard. The median Can f I value for homes with a dog in residence was 120 micrograms/gm, and for homes with no dog, 3 micrograms/gm. With few exceptions, homes with no dog in residence had less than 10 micrograms/gm. This Can f I assay will provide useful information for assessing commercial extracts as well as monitoring dog-allergen exposure and allergen-control methods.

Allergens↗

PubMed1992

Environmental control and immunotherapy for allergic disease.

Treatment for allergic disease can help prevent recurrent sinusitis. Removal of carpeting and feather bedding and use of acaricides can significantly improve symptoms caused by house dust mites or animal dander. To kill mites, wash-water temperature must be at least 58 degrees C. Patients with severe allergy should use an air-filtering vacuum cleaner and an air cleaner with a HEPA filter. Humidity should be kept at under 50%. If other measures fail, pets may have to be removed. Subcutaneous immunotherapy is effective for patients with anaphylactic reactions to insect stings, allergic rhinitis, and allergic asthma. It is ineffective for food allergy or nonallergic rhinitis or asthma. In children, immunotherapy is reserved for generalized life-threatening airway reactions. Relative indications for immunotherapy include inability to avoid the allergen and poor results or significant side effects from pharmacologic treatment. Efficacy depends on dosage, duration of treatment, and allergen selection. Low initial doses are increased at a set rate until the dose induces appropriate antibody response without significant reactions. Patients should be much improved or symptom-free for 1 to 2 years before immunotherapy is discontinued. Pollen, house dust mite, cat, and some mold spore extracts reduce symptoms and sensitivity to nasal or bronchial provocation. When used appropriately, immunotherapy is safe and effective.

Air Pollution, Indoor↗

PubMed1992

Effect of the oral leukotriene antagonist, ICI 204,219, on antigen-induced bronchoconstriction in subjects with asthma.

We studied the effect of a single oral dose of ICI 204,219 on subject response to bronchoprovocation and quantitative skin testing with standardized allergen (cat dander). Cat-allergic male subjects with asthma entered the double-blind, randomized, placebo-controlled, crossover study. Each subject received a 40 mg dose of ICI 204,219 or placebo on study days separated by at least 10 days. After dosing, each subject underwent bronchoprovocation with cat allergen until a provocative dose of allergen caused a 20% decrease in FEV1 or a maximum dose of 30,000 AU/ml was reached. Fifteen subjects entered and 13 completed the study. No significant shift in the dose-response curve of the quantitative skin test occurred in any subject. A mean tenfold increase in the interpolated provocative concentration causing a 20% decrease in FEV1 was observed between ICI 204,219 (6996 +/- 3204 AU/ml) and placebo (460 +/- 98 AU/ml). Eight of 12 subjects required more antigen to provoke a bronchoprovocation response after dosing with ICI 204,219 than that required with placebo (range, threefold to 30-fold), three demonstrated no difference (less than twofold), and one subject required less antigen after ICI 204,219 (sevenfold less). Area under the curve measurements were significantly different (p less than 0.05) between ICI 204,219 and placebo for the fixed time from the end point of the allergen bronchoprovocation to 5 hours after provocation. In conclusion, this trial demonstrates that a single oral dose of ICI 204,219 antagonizes the bronchoconstriction induced by inhaled cat allergen.

Administration, Oral↗

PubMed1992

Use of standardized and conventional allergen extracts in prick skin testing.

This study examined whether commercially available conventional and standardized allergen extracts differ enough in potency to affect routine prick skin test results. Extracts of white oak, timothy, Bermuda, Russian thistle, short ragweed, sagebrush, Alternaria, and cat dander were examined in allergic patients and in nonatopic subjects with no personal or family history of asthma, rhinitis, or eczema. Conventional nonstandardized extracts (1:10 or 1:20 wt/vol) from two sources were compared with three concentrations (100,000, 10,000, and 1000 AU/ml) of a single standardized extract. Preparations were compared in the allergic patients with computerized planimetry, and in all patients and subjects with a conventional skin test grading system. Skin test area for the conventional extracts generally fell between the 10,000 and 100,000 AU/ml concentrations of the standardized extract. Skin test reactivity to at least one allergen extract occurred in 31% of the nonatopic subjects; there was no difference between the number of 3+ and 4+ reactions for conventional and standardized extracts. Results indicate that standardized and conventional extracts are frequently similar, but are not directly interchangeable.

Adolescent↗

PubMed1993

Inhalant atopic sensitivity to grasshoppers in research laboratories.

BACKGROUND: Atopic sensitivity to insects, in both occupational and nonoccupational settings, is common. METHODS: A 26-year-old man with atopic asthma experienced worsened asthma and urticaria on exposure to grasshoppers in a research laboratory; he along with 16 other persons who work with grasshoppers from two laboratories and 26 control subjects were studied. The patient underwent a controlled allergen inhalation test with aqueous grasshopper dropping antigen. All subjects were assessed by means of a questionnaire. All but one (who refused because of severe skin reactions after contact with grasshoppers) had skin prick tests with three extracts of grasshopper and with grass pollen, cat dander, and Dermatophagoides farinae. RESULTS: The allergen challenge was positive with an isolated early asthmatic response (23% fall forced expiratory volume in 1 second [FEV1]) at 1:4096 (approximately 25 micrograms/ml), and a borderline fall in provocative concentration of methacholine causing a 20% fall in FEV1. Seven of 16 (43.8%) workers had positive grasshopper skin test results compared with one of 26 (3.8%) control subjects (p = 0.0052). Sensitization occurred even in otherwise nonatopic workers (5 of 12). Symptoms of asthma on exposure (n = 4) correlated better with positive skin test results than did cutaneous symptoms (n = 8). CONCLUSION: Atopic sensitization to grasshoppers in research laboratories is a significant occupational health problem.

Adult↗

PubMed1994

Appearance of atopic disease in relation to serum IgE antibodies in children followed up from birth for 4 to 15 years.

BACKGROUND: Few studies have addressed the relationship between sensitization and the development of atopic disease over many years. OBJECTIVE: To study the temporal relationship between the appearance of IgE antibodies in serum and atopic disease, we studied 324 children from three different groups, who were followed up prospectively from birth for 4, 12, and 15 years, respectively. METHODS: Serum samples were obtained at various ages and analyzed for IgE antibodies against egg white, cow's milk, wheat, animal dander, house dust mite, birch and timothy with Phadebas RAST (Kabi Pharmacia Diagnostics AB, Uppsala, Sweden) or Pharmacia CAP system. In addition, a screening test for atopy, the Phadiatop Paediatric test (Kabi Pharmacia Diagnostics AB) was performed. Presence of atopic disease was assessed by means of clinical examination, interviews, and questionnaires. RESULTS: In 135 children IgE antibodies were detected at least once to at least one allergen. Antibodies to egg white appeared in 46 children before or at 2 years of age: in 57% of them IgE antibodies to inhalants developed within the next 2 years, and in 19 of 25 (76%) IgE antibodies to inhalants developed before or at 12 to 15 years. Antibodies to inhalant allergens appeared in 55 children during the first 4 years of life and in 64 before 12 to 15 years. Among the former 48% and among the latter 32% had previously detectable egg white antibodies. Atopic disease appeared before or at age 4 years in 80% of the 40 children with IgE antibodies against egg white up to 9 months of age and in 69% of the 58 children who had a positive Phadiatop Paediatric test result in infancy. CONCLUSIONS: IgE antibodies in children are usually associated with current or later topic disease. Sensitization to foods in infants is usually associated with appearance of IgE antibodies to inhalants later in life.

Adolescent↗

PubMed1994

Evaluation of the new ophthalmic antihistamine, 0.05% levocabastine, in the clinical allergen challenge model of allergic conjunctivitis.

The objective of this study was to evaluate the efficacy of 0.05% levocabastine, a new antihistamine formulated for ophthalmic use, compared with the placebo vehicle for the treatment of allergic conjunctivitis induced by ocular allergen challenge. Subjects who reacted. positively in both eyes on two separate occasions to ocular allergen challenge with grass, ragweed, or cat dander (N = 47) received one dose of 1 to 2 drops of 0.05% levocabastine in one eye and its vehicle in the other eye. After 10 minutes, the predetermined dose of allergen was instilled in both eyes. Signs and symptoms of allergic conjunctivitis were evaluated with biomicroscopy and subjective evaluation of itching after 3, 5, and 10 minutes. Four hours after drug administration, subjects were rechallenged and reevaluated to determine levocabastine's duration of action. Results showed that levocabastine was significantly more effective than placebo in inhibiting itching, hyperemia, eyelid swelling, chemosis, and tearing after the initial challenge and in inhibiting all parameters except eyelid swelling after the rechallenge 4 hours later (p < 0.05). These results demonstrate that levocabastine, currently the only ophthalmic antihistamine available that is not combined with a vasoconstrictor, is efficacious in the inhibition of itching, as well as all of the allergic signs of a vascular origin, with a duration of action of at least 4 hours. Because of its strong effects on itching and hyperemia, chemosis, lid swelling, and tearing, levocabastine would be a valuable therapeutic agent to add to the heterogeneous family of antiallergic compounds presently available for the treatment of seasonal allergic conjunctivitis.

Adolescent↗

PubMed1994

Fine specificity of B-cell epitopes on Felis domesticus allergen I (Fel d I): effect of reduction and alkylation or deglycosylation on Fel d I structure and antibody binding.

The repertoire of B-cell epitopes on the major cat allergen, Fel d I, was analyzed with monoclonal antibodies (MoAbs) in topographic mapping studies and in immunoassays with antigen derived from other cat (Felidae) species. Four essentially nonoverlapping epitopes on Fel d I, designated Fd1A to D, were defined by use of 15 anti Fel d I MoAbs in cross-inhibition radioimmunoassay. Only MoAbs directed against epitope Fd1B bound to putative Fel d I homologues in hair and dander extracts from seven other feline species (Panthera species, [n = 5], Leptailurus serval, and Leopardus pardalus). Quantitative monosaccharide analysis showed that Fel d I was a glycoprotein, containing high levels of fucose, as well as glucosamine, galactose, and mannose. Binding of MoAbs and human IgG or IgE antibody to native, reduced and alkylated or deglycosylated Fel d I was compared by means of immunoprecipitation and immunoassay, and the effects of these treatments on the structure of Fel d I were analyzed by sodium dodecylsulfate-polyacrylamide gel electrophoresis. On reduction and alkylation, Fel d I dissociated into 14 kd and 3.2 kd peptides, and deglycosylation with trifluoromethane sulfonic acid produced a 12 to 14 kd peptide. These procedures resulted in a 100- to 1000-fold loss in murine or human antibody binding activity and caused significant loss of secondary structure, as judged by circular dichroism spectroscopy. Treatment with potassium hydroxide also caused a marked loss in antigenic reactivity. In contrast, enzymatic deglycosylation generated a 9 kd peptide, which showed strong reactivity with murine and human antibodies, comparable to native Fel d I. The results show that MoAbs define a broad repertoire of B-cell epitopes on Fel d I, one of which is expressed by other cat species. These epitopes are conformational and do not appear to involve oligosaccharide residues.

Alkylation↗

PubMed1988

Activation of the classical pathway of human complement in vitro by house-dust extracts is caused by IgM antibodies to polysaccharide antigen(s) and is not related to atopy.

The mechanism of activation of the classical pathway of human complement by house-dust extracts and its relevance to atopic disease was studied. Our results confirm that for most sera of adults, house-dust extract is, on a weight basis, a more potent C-activator than aggregated human IgG or lipopolysaccharide (endotoxin). Naturally occurring IgM antibodies directed against ubiquitous polysaccharides appeared to be the dominant factor in the C1 activation by house-dust extracts in human sera. Large variations were found between sera with respect to the concns of these IgM antibodies as measured by C1 activation or fixation of haemolytic complement. The IgM antibody titre was, however, not associated with atopic disease. Consequently, we do not support the hypothesis put forward by Berrens et al. (1978) (Allergol. Immunopath. 6, 45-54) that there might be a relation between atopy and enhanced reactivity of serum complement with allergenic extracts. More than 90% of the C-activating potential of allergen extracts like house dust was found in the fractions with high mol. wt material (mol. wt greater than 100 K). Therefore, these antigens are easily separated from the known IgE-binding major allergens of house-dust mite and cat dander.

Adolescent↗