Studies on IgG subclass antibodies in adult asthma. 2. Changes in serum antigen specific IgG subclass antibodies for aging and intractability in asthmatics]

To clarify the factors which induce intractable asthma, the level of serum IgG subclass antibodies to mite (Dermatophagoides farinae) and Candida antigens (Candida albicans) for aging and severity was investigated in 230 bronchial asthmatics (Male: 117, Female: 113) aged 6-81 years old (mean age = 40). Total IgE level and IgE antibodies to mite and Candida antigens were measured by radioimmunosorbent test (RIST) and radioallergosorbent test (RAST), respectively. The serum level of IgG and IgG1 antibodies to the antigens were measured by enzyme-linked immunosorbent assay (ELISA). The results were as follows: 1) The incidence of severe asthma in aged and late onset asthmatics, especially late onset intractable asthma (LOIA), was higher than that in young and early onset asthmatics. 2) The serum level of total IgE and IgE antibodies to mite in aged and late onset asthmatics was lower than that in young and early onset asthmatics. 3) The incidence of severe and intractable asthmatics in the group of low IgE levels (less than 300 IU/ml) was higher than that in the group of high IgE levels (over 500 IU/ml). The incidence of positive IgE (RAST) score to mite in severe and intractable asthmatics was lower than that in mild and moderate asthmatics. 4) Considering aging, the serum levels of IgG and IgG1 antibodies to mite and Candida in severe and intractable asthmatics was higher than those in mild asthmatics. These data indicate that the aged and late onset asthmatics may produce dominantly the IgG (IgG1) antibody to the antigens, and have severe asthma attacks caused by IgG (IgG1) rather than IgE antibody.     

Studies on IgG subclass antibodies in adult asthma. 1. Serum antigen specific IgG subclass antibodies in asthmatics with late asthmatic response

It is clear that immediate asthmatic response is mediated by IgE-dependent mechanisms. However, late asthmatic response is induced by inhalation of antigens without antigen specific IgE antibodies in some asthmatics, especially in intractable asthma induced by Candida antigen. To elucidate the relationship between those bronchial responses and antibodies, antigen specific IgG subclass antibodies in sera from asthmatics were measured and compared with IgE antibody. The results were as follows. 1. Avidin-biotin ELISA (enzyme-linked immunosorbent assay) method was established for the measurement of specific IgG and IgG subclass antibodies to mite or Candida antigen. 2. Serum levels of antigen specific IgG and IgG1 antibodies in asthmatics with LAR provoked by mite or Candida antigen were significantly higher than those in asthmatics without LAR (p less than 0.01). 3. Serum levels of specific IgE antibody to these antigens in asthmatics with LAR provoked by mite or Candida antigen were slightly lower than those in asthmatics without LAR, though the difference is not significant. These results suggest that high serum levels of specific IgG and IgG1 antibodies to these antigens play a role in inducing LAR in asthmatics with LAR.     

Immunologic observations in sera of a patient with allergic bronchopulmonary aspergillosis by means of the enzyme-linked immunosorbent assay

Titers of IgG, IgA, and IgM antibodies against Aspergillus fumigatus were measured by ELISA in sera of a patient with allergic bronchopulmonary aspergillosis during an acute stage, remission, and exacerbation of the disease. Total IgE, specific IgE against A. fumigatus, and number of precipitation lines were also measured. ELISA IgG-, IgA-, and IgM-antibody titers were expressed in percentages of the titer of a strongly positive standard serum by use of the patient's own serum as a standard. The fall in antibody concentration (in percent) and elevations during exacerbation appeared to be similar for these antibody classes and are related with the number of precipitates measured by double immunodiffusion. Furthermore, the changes in antibody titers were also similar to the elevations and decreases in both total IgE and specific-IgE antibodies (also expressed in percentages of a chosen standard serum). The ELISA IgG-antibody titers were higher compared with the ELISA IgA or IgM titers and demonstrated a continuous decline during a period of 2 yr after the acute phase of ABPA. Therefore, IgG-antibody titers are preferred as an indicator of disease activity in follow-up studies over longer time periods and are at least as sensitive as the measurement of concentrations of IgE antibodies.     

IgE and IgG anti-house dust mite specificities in allergic disease

BACKGROUND: There are few studies that quantitatively compare IgE and IgG antibody binding to the major and minor house dust mite allergens. OBJECTIVE: To measure the IgE and IgG antibody specificities produced by adults and children, including children admitted to an emergency department for asthma. METHODS: Antibodies were measured by solid-phase microtiter assays. RESULTS: Children recruited from the emergency department had similar titers and patterns of IgE antibody binding compared with children without acute disease. Der p 1 and 2 bound 50% to 65% of the IgE antibody, and most of the remaining binding was to Der p 4, 5, and 7. Der p 3, 8, 10, and 20 induced low titers. The pattern was similar across a wide range of antihouse dust mite titers. IgG(1) and IgG(4) antibodies predominantly bound the major and midrange allergens and were mainly found in children with allergy. Children recruited in the emergency department had lower titers. CONCLUSION: The same IgE antibody-binding pattern and predominant contribution of Der p 1 and 2 was found across a wide range of total IgE antibody titers and for children admitted to an emergency department. IgG(1) and IgG(4) antibodies bound to the more allergenic specificities and were largely found in children with allergy. The IgG antibody titers were lower in sera from children admitted to the emergency department for asthma exacerbations. CLINICAL IMPLICATIONS: Der p 1 and 2 and possibly Der p 4, 5, and 7 provide a formulation suitable for immunotherapy and diagnosis. Low IgG antibodies were a feature of acute disease.     

Contribution of dust mite and cat specific IgE to total IgE: relevance to asthma prevalence

BACKGROUND: The prevalence of asthma is strikingly different in some Westernized countries: approximately 20% in New Zealand and approximately 8% in northern Sweden. OBJECTIVE: We investigated differences in total IgE and in the prevalence of wheezing related to the observation that high exposure to dust mite allergens induces high titers of IgE antibodies. METHODS: Two age-matched, population-based cohorts-1155 children in New Zealand (224 sera) and 3431 children (797 sera) in the Norrbotten area of Sweden-were studied. Sera were assayed for total IgE and specific IgE antibodies to relevant allergens. RESULTS: The mean total IgE among wheezing children was higher in New Zealand than Sweden (218 IU/mL vs 65.2 IU/mL; P < .001). In addition, the prevalence of high titer specific IgE antibody (> or =50 IU/mL) was greater among the wheezing children in New Zealand compared with Sweden (35.7% vs 13.0%; P < .001). Specific IgE antibody to mite in New Zealand was significantly related to high total IgE (> or =200 IU/mL; r = 0.47; P < .001), whereas the IgE antibody response to cat allergens did not make a significant contribution to high total IgE in either country. CONCLUSION: The quantity of IgE antibody produced to dust mite provides a possible explanation for the higher total IgE levels found in children in New Zealand and may help to explain the differences in prevalence and severity of asthma between these 2 countries. CLINICAL IMPLICATIONS: Specific IgE antibody responses to dust mite and cat allergens may contribute differently to total serum IgE and to the prevalence of allergic disease.     

Inhibition of the passive cutaneous anaphylaxis reaction to Dactylis glomerata pollen allergens by a purified component of this pollen

By isoelectric focusing a protein fraction of pI 4.6 was isolated from a crude water-soluble extract of Dactylis glomerata pollen (SE). This fraction was neither immunogenic nor allergenic in BALB/c mice. In one week, this protein inhibited the mouse IgE-specific antibodies to the soluble extract as measured by PCA in rats and was therefore called Dactylis inhibitory protein (DIP). Two experimental approaches which lowered IgE anti-SE titer were undertaken. Pretreatment with DIP as well as injection of DIP after the last sensitizing injection with SE resulted in an inhibition of the circulating IgE antibody level to SE. For both experiments the regulation of the immune response touched only the IgE class, whereas the titers of anti-SE IgG, IgM, IgA antibodies were not modified. DIP treatment did not alter the IgE titers, measured by PCA, in the immune response to ovalbumin.     

Measurement of IgE, IgG1 and IgG4 antibodies against mite Sephadex fractions and purified allergens by means of enzyme-linked immunosorbent assay

Mite antigens (Dermatophagoides farinae) were fractionated by a Sephadex G-200 column and their reactivities with IgE, IgG1 and IgG4 antibodies were investigated with enzyme-linked immunosorbent assay (ELISA). High IgE antibody values were observed in fractions with low molecular weight (allergenic part), while high IgG1 and IgG4 antibody values were observed in fractions with high molecular weight. High IgG4 antibody values to crude mite extract and fractions with high molecular weight were detected in individuals who had received immunotherapy. However, IgG4 antibodies directed to allergenic part were found in only one out of 12 sera tested. IgG4-ELISA using DF1 (major allergen of Dermatophagoides farinae) as antigen was also performed. In the group treated with mite, significant IgG4 antibody levels were detected in only one out of 13 sera tested. In the group treated with house dust, significant IgG4 antibodies were detected in only one out of 12 sera tested. Patients who showed high IgG4 antibody responses to crude mite extract and to high molecular weight did not show responses to allergenic part and DF1. The only case who showed positive IgG4 responses to allergenic part also reacted with DF1. Those results suggest that IgG1 and IgG4 antibody values in ELISA using crude mite extract as antigen do not reflect major allergen-specific antibody values. The importance of the use of partially purified antigens in measuring major allergen-specific IgG4 antibodies was also suggested.     

Class-specific antibody determination against Aspergillus fumigatus by means of the enzyme-linked immunosorbent assay. III. Comparative study: IgG, IgA, IgM ELISA titers, precipitating antibodies and IgE binding after fractionation of the antigen

IgG, IgA and IgM ELISA antibody titers against Aspergillus fumigatus were elevated in sera of patients with aspergilloma and allergic bronchopulmonary aspergillosis (ABPA), showing higher titers for the IgG antibodies compared with the IgA and IgM antibodies. No differences were found between titers of identical antibody classes in the two groups of sera. IgG and IgA ELISA titers were highly specific whereas IgM ELISA showed more unspecific binding of IgM antibodies. Antibodies, as measured by ELISA, studied after fractionation of the antigen into fractions of decreasing molecular weight, showed a preferential binding by the high molecular weight fractions. Precipitating antibodies studied in patient sera did not always correspond with the IgG ELISA titers. IgE antibody binding was observed in all fractions from Sephadex G-100 fractionated components; maximum binding was found with fractions of 28,000-60,000 daltons. The low molecular weight fractions (18,000-less than 5,000 daltons) showed less IgE binding but the quantity of this fraction was higher. The discrepancies noted between the IgG and IgA ELISA titers and the binding of IgM or IgE antibodies indicate that antigenic components may in part differ in the binding of antibody classes.     

Age-related changes in specific IgE antibody production.

We measured specific IgE antibodies to mites and Japanese cedar pollen (JCP) in a general population aged from 18 to 99 years by fluorescence enzyme immunoassay and analyzed the relationship of antigen-specific IgE antibody production to aging. The incidence of mite antibody carriage gradually decreased in proportion to age from 26.7% at 18 to 19 years of age to 15.9% for the 60 to 69 age group and then decreased markedly in the subjects aged 70 and over. A similar tendency was found with regard to JCP antibody positivity. The highest levels of antibodies to both mites and JCP were found in young adults, and these levels decreased with age. There was a significant negative correlation between the mean relative fluorescence unit value for specific IgE antibodies and age (mite antibody: r = -.957 and JCP antibody: r = -.954). No significant correlation was found between mite antibody levels and JCP antibody levels in the individual subjects.     

The relevance of microbial allergens to the IgE antibody repertoire in atopic and nonatopic eczema

BACKGROUND: A propensity to microbial skin infections has been reported in atopic ("high IgE") and nonatopic ("low IgE") forms of eczema. However, the relationship between antimicrobial IgE antibodies and nonatopic disease is unclear. OBJECTIVE: We examined the relevance of microbial allergens to the allergen-specific IgE antibody repertoire in patients with atopic dermatitis. METHODS: Patients with IgE levels of less than 150 IU/mL were stratified according to sensitivity (n = 22) or no sensitivity (n = 27) to 11 common food allergens and aeroallergens. The prevalence and titers of antimicrobial IgE antibodies were compared with those of patients (n = 36) with increased total IgE levels (>150 IU/mL). Skin-derived serum chemokines were also analyzed. RESULTS: Patients with low IgE levels showed decreased disease severity, increased age of onset, a striking female predominance, and a distinct distribution of skin lesions. High titer IgE antibodies (sum of 8 bacterial and fungal allergens = 29.8 +/- 32.6 IU/mL) and multisensitization specific for microbial allergens was characteristic of patients with high IgE levels, with an overall 84% positivity; however, antimicrobial IgE antibodies comprised 3% or less of allergen-specific IgE antibodies. By contrast, antimicrobial IgE antibodies were detected in only 20% of patients with low IgE, and titers were negligible, irrespective of sensitization to common allergens. These patients were monosensitized, and exclusive microbial sensitivity was uncommon (10%). Patients with low IgE with no sensitivity to common allergens had lower levels of serum macrophage inflammatory protein 3alpha compared with their sensitized counterparts. CONCLUSION: Antimicrobial IgE antibodies are uncommon in patients with atopic dermatitis with low IgE levels. CLINICAL IMPLICATIONS: Hypersensitivity to microbial allergens is an unlikely trigger for eczematous eruptions in patients with low IgE levels.     

Detection of mosquito saliva-specific IgE antibodies by capture ELISA

We developed an IgE-capture ELISA and measured mosquito saliva-specific IgE antibodies in 27 children sensitive to mosquito bites. Children with large 15-min bite wheals had significantly higher ( P < 0.0005) mosquito saliva-specific IgE levels than children with small wheals. In the latter group, the saliva-specific IgE level was significantly higher ( P =0.031) than the levels of six infants never exposed to mosquitoes. A positive correlation ( r =0.65; P =0.0002) was found between the size of the 15-min wheal and the mosquito saliva-specific IgE antibody levels. These results further support the role of mosquito saliva-specific IgE antibodies in the pathogenesis of mosquito-bite whealing. Compared to immunoblotting, IgE-capture ELISA provides a quantitative method to measure mosquito saliva-specific IgE antibodies.     

Production of IgE antibodies to mite in guinea pigs by nasal immunization

There has been no report that IgE antibodies can be raised in guinea pigs by immunizations through respiratory tracts. We dropped a 0.1 ml mixture of 50 micrograms mite extract and aluminium hydroxide gel (Alum) into each of both nostrils of 5 guinea pigs. A mite extract alone was dropped into the nostrils of another 5 guinea pigs. The immunization was done every week. IgE antibodies were detected in one of guinea pigs sensitized 5 times with Alum + mite and also in another guinea pig in the same group sensitized 10 times. No IgE antibodies were detected in the animals immunized with mite alone.     

Citrus red mite (Panonychus citri) is the most common sensitizing allergen of asthma and rhinitis in citrus farmers.

OBJECTIVE: To evaluate type I hypersensitivity to citrus red mite (Panonychus citri), its prevalence, and relationship to respiratory dysfunction, a cross-sectional survey was performed among citrus farmers on Cheju Island, Korea. MATERIALS AND METHODS: Questionnaires, and skin prick test responses to 11 common inhalant allergens and citrus red mite were performed in 181 citrus farmers, and serum-specific IgE antibodies to citrus red mite were measured by ELISA in sera of 123 subjects. To determine airway hyperresponsiveness, methacholine bronchial provocation tests were performed in 55 subjects who complained of recurrent lower respiratory symptoms. RESULTS: The prevalence of asthma-based on presence of asthmatic symptoms on the questionnaire and airway hyperresponsiveness to methacholine, and allergic rhinitis based on presence of nasal symptoms on the questionnaire and positive skin-test response were 12.1% and 19.3%, respectively. The positive rate of skin responses to one or more of 11 common inhalant allergens excluding citrus red mite was 17.1%, and if citrus red mite was included, 25.9% of farmers had positive responses. On skin prick tests, citrus red mite (16.5%) was the most common sensitizing allergen, followed by cockroach (11.0%), Dermatophagoides pteronyssinus (9.9%), and D. farinae (9.3%). Among farmers with asthma and allergic rhinitis, the positive skin responses to citrus red mite were noted in 54.5 and 68.5%, respectively. Serum-specific IgE antibodies to citrus red mite were detected in 45 farmers (36. 5%) of the 123 tested, and there was significant correlation between specific IgE level and weal (A/H ratio) to citrus red mite (r = 0.57, P < 0.001). The prevalence of asthma was higher in subjects with positive skin responses or high serum-specific IgE antibodies to citrus red mite than in those without skin response or serum specific IgE (P < 0.05, respectively). CONCLUSION: Citrus red mite is the most important allergen in citrus farmers with asthma and rhinitis in which causative allergen has not been identified. It should be included in the skin test battery for screening the causative allergen in farmers exposed to citrus red mite.     

Use of a chimeric ELISA to investigate immunoglobulin E antibody responses to Der p 1 and Der p 2 in mite-allergic patients with asthma, wheezing and/or rhinitis

BACKGROUND: Sensitization to indoor allergens, particularly to dust mites, is a strong risk factor for asthma in children and adults. Assessment of sensitization is carried out using in vivo and in vitro tests to detect specific IgE antibodies. OBJECTIVE: To investigate IgE antibody responses to mites in patients with asthma, wheezing and/or rhinitis, using chimeric ELISA to measure specific IgE antibodies to mite allergens Der p 1 and Der p 2. METHODS: Specific IgE antibodies to Der p 1 and Der p 2 were quantified by chimeric ELISA, and compared with IgE to Dermatophagoides pteronyssinus (Dpt) measured using the CAP system (Pharmacia). A panel of sera from 212 patients with asthma, wheezing and/or rhinitis and 11 controls was analysed. RESULTS: There was a significant correlation between IgE to Dpt measured by CAP and IgE to Der p 1 (r = 0.81, P < 0.001), Der p 2 (r = 0.79, P < 0.001) and combined Der p 1 and Der p 2 (r = 0.86, P < 0.001). Seventy per cent of all patients had IgE to Dpt, and of those, 76.5% had IgE to Der p 1, 79.2% had IgE to Der p 2 and 83.1% had IgE to Der p 1 and Der p 2 combined. Considering the cut-off level of 2 IU/mL of IgE to either Der p 1 or Der p 2, the predictive value for a positive IgE to Dpt by CAP was greater than 95%. CONCLUSIONS: The chimeric ELISA allowed accurate quantification of IgE antibodies to Dpt allergens Der p 1 and Der p 2, and it could be useful for studying immune responses to mites in patients with asthma and/or rhinitis.     

Measurement of murine IgE antibody responses to dust mite allergens by in vitro assay.

In an analysis of murine immune responses to the dust mite allergen Der p 1, treatment with purified allergen induced a significant increase in the level of circulating IgE immunoglobulin (from less than 100 ng/ml in normal mice to 1,350 ng/ml in mice receiving the allergen). Even so, specific IgE antibodies binding to purified Der p 1 were not detected in a conventional ELISA, and the major response appeared to be the induction of high titre IgG antibodies. Specific circulating murine IgE antibodies were however detected using the following assay format: murine IgE was captured to anti-murine IgE antibody coated wells; Der p 1 was added and bound by immobilized anti-Der p 1 IgE antibodies; the captured Der p 1 was then detected by the addition of monoclonal IgG antibodies against Der p 1 and these antibodies were measured by the addition of anti-murine IgG antibody-enzyme conjugate with which colour development is produced after substrate addition. This assay establishes a procedure to measure circulating anti-Der p 1 IgE antibodies which are present together with competing high titre IgG anti-Der p 1 antibodies.     

Do levels of immunoglobulin G antibodies to foods predict the development of immunoglobulin E antibodies to cat,dog and/or mite?

BACKGROUND: In children at high risk of inhalation allergy, food sensitization is associated with an increased risk for sensitization to inhalant allergens. Furthermore, this association was also found in a cross-sectional study. OBJECTIVE: To examine in a prospective study, whether levels of IgG to foods (i.e. mixture of wheat and rice, mixture of soy bean and peanut, egg white, cow's milk, meat, orange and potato) indicate an increased risk for the future development of IgE antibodies to inhalant allergens in a low-risk population and whether they can be used as predictors of the subsequent development of IgE antibodies in young, initially IgE-negative children. METHODS: Coughing children, aged 1-5, visiting their GPs, were tested for IgE antibodies to mite, dog and cat (RAST) and IgG (ELISA) to foods. All IgE-negative children were retested for IgE antibodies after two years. The IgG results (66 percentiles) of the first blood sample were compared to the RAST-scores of the second blood sample. RESULTS: After two years, 51 out of 397 (12.8%) originally IgE-negative children, had become IgE-positive for cat, dog and/or mite. An increased IgG antibody level to wheat-rice (OR = 2.2) and to orange (OR = 2.0) indicated an increased risk of developing IgE to cat, dog or mite allergens. In addition to IgG to a mixture of wheat-rice and orange; total IgE, breastfeeding, eczema as a baby and age were the most important predictors for the subsequent development of IgE to inhalant allergens. DISCUSSION: An increased IgG antibody level to a mixture of wheat-rice or orange, indicates an increased risk of developing IgE to cat, dog or mite allergens. This indicates that excessive activity of the mucosal immune system is present before IgE antibodies to airborne allergens can be demonstrated. Nevertheless, IgG to foods is not very helpful (with a positive predictive value of 16.5%, and negative predictive value of 90.6%) in identifying individual children at risk in clinical practice. However, besides other risk factors, IgG to wheat-rice and to orange could be useful as a screening test for studies in the early identification, i.e. before IgE antibodies can be detected, of children with an increased risk of developing IgE antibodies in the future.     

IgE antibody production in rats against multiple components of excretory-secretory products of the nematode Nippostrongylus brasiliensis.

Infection with the nematode Nippostrongylus brasiliensis (NB) induces the intense production of specific and non-specific immunoglobulin E (IgE) in rats. In the present study, we analysed NB-derived allergenic substances and the variability of IgE antibody production in response to these allergens in outbred Sprague-Dawley rats. Two kinds of crude allergens were used: the excretory-secretory products (ES) of adult NB, and an extract of homogenized adult worms (AW). ELISA showed that IgE antibody titres to ES were more than five times higher than the titres to AW. In the homologous passive cutaneous anaphylaxis (PCA) reaction using serum from infected rats, as little as 50 micrograms of ES had a maximal PCA activity, while even 1 mg of AW still gave a slightly lower PCA titre. Thus, it appeared that ES contained more allergen than AW at the same amount of total proteins. By immunoblot analysis, at least six components were recognized by IgE antibodies from infected animals, and these components were exactly the same in both ES and AW. The results indicated that the allergenic components in ES and AW were the same molecules, and that only those molecules which could be excreted or secreted from living worms were allergenic. Among the array of allergens, 130,000 and 70,000 molecular weight (mw) molecules were commonly recognized by IgE from all serum samples examined, while other components of the allergens were recognized variably by IgE antibodies from individual animals. These findings suggested that individual animals varied considerably in their IgE antibody production to the different constituents of the nematode allergens.     

Association between the occurrence of the anticardiolipin IgM and mite allergen-specific IgE antibodies in children with extrinsic type of atopic eczema/dermatitis syndrome

BACKGROUND: As the literature has only controversial data on the role of nonallergen-specific antibodies in atopic eczema dermatitis syndrome, the authors investigated the link between the occurrence of the antiphospholipid [anticardiolipin (ACL), anti-beta2-glycoprotein I] and allergen-specific immunoglobulin E (IgE) antibodies in 72 children with atopic eczema/dermatitis syndrome (AEDS). METHODS: The measurement of antiphospholipid antibodies was carried out by enzyme-linked immunosorbent assay (ELISA), serum total IgE by nephelometry, and allergen-specific IgE by immunoblotting assay. The statistical analysis was carried out by Fisher's exact test and odds ratio was calculated. RESULTS: Thirteen of 72 children with AEDS (mean age 8.3 years) had elevated serum levels of ACL, and eight anti-beta2-glycoprotein I antibodies. The presence of allergen-specific IgE against inhalant allergens and nutritive allergens was among eight of 13 and three of eight in the cases with elevated ACL. The ratio of patients with highly increased severity scoring of atopic dermatitis (SCORAD) index (>75) was significantly higher in the group with elevated (4/13) than in those with the normal ACL levels (2/59). There was a significant association between the appearance of mite (Dermatophagoides pteronyssinus, D. farinae)-specific IgE and ACL IgM antibodies (6/13). CONCLUSION: These findings show that there are significant linkage and association between the appearance of ACL IgM or the production of allergen-specific IgE against inhalant (mainly mite) allergens in children with atopic eczema/dermatitis syndrome.     

Total and specific serum IgE levels in adults: relationship to sex, age and environmental factors

Abstract. We studied total and specific serum IgE levels cross-sectionally, potential predictors of obstructive lung disease, in a stratified random sample of 18–73-year-old adults ( n = 1512). The attendance rate was 84%. The total IgE level and prevalences of specific IgE antibodies against house dust mite and cat were higher for men than for women. Specific IgE levels decreased by increasing age, while total IgE decreased in women only. Smokers had a higher IgE level than non-smokers, while non-smokers had more often specific IgE antibodies against timothy and birch than smokers. Subjects with occupational dust or gas exposure had a higher total IgE level than unexposcd. The general population prevalences were for specific IgE antibodies against timothy 4.5%, house dust mite 3.2%, birch 2.6%, cat dander 1.6% mould 0.2% and against any of these 7-6%. In a multivariate analysis age, occupational dust or gas exposure as well as the interaction terms between sex and age and between smoking and paek-years were independent predictors for total IgE levels. Male sex, young age, never having smoked and the season of the year were independent predictors for having one or more of the five specific IgE antibodies. Subjects with total serum IgE in the highest quintile (≥66 kU/1) had an adjusted odds ratio of 37 (95% confidence interval: 11–120) for having one or more of the specific IgE antibodies examined, compared with those in the lowest quintile (< 5 kU/1). Demographic and environmental factors were thus predictors of total and specific IgE levels in this adult community. These factors should be taken into account when examining relationships between IgE levels, markers of allergy and inflammation, and airways disease.     

IgE in experimental schistosomiasis. II. Quantitative determination of specific IgE antibodies against S. mansoni: a follow-up study of two strains of infected rats. Correlation with protective immunity.

Parasite specific IgE antibodies in rats infected with Schistosoma manoni were measured by passive cutaneous anaphylaxis (PCA) reactions and by the technique of immuno-adsorption. Two strains, one a low IgE producer (Fischer rats) and the other a high IgE producer (Hooded-Lister rats) were studied. In Fischer rats, a time course study of the occurrence of IgE antibodies and resistance to reinfection was made. Parasite specific IgE levels measured by immuno-adsorpiton were much lower than total IgE levels and a similar percentage of specific IgE (about 8%) was in the two strains.IgE antibodies were maximum at day 30 and day 60 after infection; however, a third peak at day 90 was observed only in Fischer rats. Some discrepancies between results obtained by PCA and immunosorbent techniques have been observed, which could be explained by differences in the affinity of IgE antibodies during infection or by the presence of total IgE in the PCA assay. There was a close parallelism between specific IgE antibodies levels and the course of immunity in Fischer rats. This parallelism supports the view that IgE could play a pre-eminent role in protective immunity in rat schistosomiasis.