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Allergen-specific IgE (allergen-specific + ige)

Distribution by Scientific Domains

Medical Sciences	100%

Distribution within Medical Sciences

Allergy & Clinical Immunology	83%
Dermatology	12%

Selected Abstracts

Evidence for allergen-specific IgE of maternal origin in human placenta

ALLERGY, Issue 6 2009
M. Joerink
Background:, Immunoglobulin E (IgE) has been identified on macrophage-like cells in the villi of human placenta, irrespective of the serum IgE levels or allergy status of the mother. The origin of placental IgE is debated and it is not known if it is spontaneously produced, so-called ,natural IgE', or if it has any specificity for certain allergens. The aim of this study was to investigate if placental IgE originates from mother or child and to analyse its specificity. Methods:, Immunoglobulin E was eluted from placenta by lowering the pH. Total and allergen-specific IgEs were measured in placenta eluate, maternal and cord blood plasma by means of ImmunoCAP (Phadia AB). The levels of natural antibodies were determined with an anti-phosphorylcholine (PC) enzyme-linked immunosorbent assay, as natural IgE has been shown in one previous publication with this assay. Results:, Detectable amounts of IgE were eluted from 11/12 full-term placentas. Natural (anti-PC) IgE antibodies were detected in low amounts in maternal plasma but not in the placental eluate or in cord blood plasma. There was a significant correlation between the amount of total IgE eluted from placenta and the levels of total IgE in maternal plasma; however, not between maternal and cord blood plasma. Allergen-specific IgE was only found in placental eluates from mothers with specific IgE towards these allergens. Furthermore, there was a significant correlation between the amount of allergen-specific IgE eluted from placenta and the levels of allergen-specific IgE in maternal plasma. Allergen-specific IgE could not be detected in cord blood. Conclusion:, These results suggest a maternal origin of placental IgE, which can be allergen-specific. [source]

Helminths, allergic disorders and IgE-mediated immune responses: Where do we stand?

EUROPEAN JOURNAL OF IMMUNOLOGY, Issue 5 2007
Klaus
Abstract Th2 responses induced by allergens or helminths share many common features. However, allergen-specific IgE can almost always be detected in atopic patients, whereas helminth-specific IgE is often not detectable and anaphylaxis often occurs in atopy but not helminth infections. This may be due to T regulatory responses induced by the helminths or the lack of helminth-specific IgE. Alternatively non-specific IgE induced by the helminths may protect from mast cell or basophil degranulation by saturating IgE binding sites. Both of these mechanisms have been implicated to be involved in helminth-induced protection from allergic responses. An article in the current issue of the European Journal of Immunology describes the generation of an anti- Nippostrongylus brasiliensis -specific IgE antibody which was used to identify a novel N. brasiliensis antigen (Nb-Ag1). The authors demonstrated that Nb-Ag1 specific IgE could only be detected for a short period of time during infection, and that these levels were sufficient to prime mast cells thereby leading to active cutaneous anaphylaxis after the application of Nb-Ag1. This is the first report clearly showing that a low level of helminth-specific IgE, transiently produced, is able to induce mast cell degranulation in the presence of large amounts of polyclonal IgE. See accompanying article: http://dx.doi/10.1002/eji.200737135 [source]

Atopic eczema or atopiform dermatitis

EXPERIMENTAL DERMATOLOGY, Issue 4 2010
Jan D. Bos
Please cite this paper as: Atopic eczema or atopiform dermatitis. Experimental Dermatology 2010. Abstract:, Age period prevalence of atopic eczema (AE), a very common skin disease, has increased during the past decennia. This expansion seems to be ending in wealthy countries, while an increase is observed in developing nations, for which there is no firm explanation. Recent steps in understanding AE are the detection of skin barrier related filaggrin null mutations in approximately 25% of patients and the recognition of IL-31 as a molecule possibly involved in the itch (pruritus). Also interesting are the recognition of thymus and activation-regulated chemokine (TARC) and proliferating-inducing ligand (APRIL), as being associated with AE severity and activity. Immunocentric and corneocentric views on pathogenesis (the inside-outside paradigm) and the diagnostic entity atopiform dermatitis (AFD) are discussed here. We emphasize that diagnosing AE is not simple but challenging. We accentuate that a diagnosis of AE is only possible when there is allergen-specific IgE. Advice as to the need for elimination of allergens and adjustment of lifestyle are only proficient in patients having atopy and true AE, not in those having AFD. [source]

A convenient and sensitive allergy test: IgE crosslinking-induced luciferase expression in cultured mast cells

ALLERGY, Issue 10 2010
R. Nakamura
To cite this article: Nakamura R, Uchida Y, Higuchi M, Nakamura R, Tsuge I, Urisu A, Teshima R. A convenient and sensitive allergy test: IgE crosslinking,induced luciferase expression in cultured mast cells. Allergy 2010; 65: 1266,1273. Abstract Background:, For the detection of allergen-specific IgE in sera, solid-phase IgE-binding assays like the CAP test are commonly used. Although such immunochemical methods are very sensitive, they frequently produce false positives. Degranulation of the human IgE receptor (Fc,RI)-transfected rat mast cell (RBL) lines seems to be a possible indicator for human IgE, but spontaneous mediator release from these cells in the presence of human sera is not negligible. Methods:, The nuclear factor of activated T-cells (NFAT)-responsive luciferase reporter gene was stably transfected into human Fc,RI-expressing RBL-SX38 cells. One established clone (RS-ATL8) was sensitized with 1 : 100 dilution of sera from patients with egg white allergy and then stimulated with purified or a crude extract of egg white allergen. Results:, Sensitization with 15 pg/ml IgE was sufficient to detect IgE crosslinking,induced luciferase expression (EXiLE) by anti-IgE stimulation. Allergen-specific EXiLE was elicited by as little as 1 fg/ml of egg white protein without cytotoxicity. There was a good correlation between results with EXiLE and oral food challenge tests on patients with egg allergy (P = 0.001687, Fisher's exact test). The measured values of EXiLE and the CAP test also correlated well (R = 0.9127, Spearman's test). Conclusion:, The EXiLE test using RS-ATL8 cells is a promising in vitro IgE test to evaluate the biological activity of the binding between IgE and allergens. [source]

Relationship of serum cholesterol levels to atopy in the US population

ALLERGY, Issue 7 2010
M. B. Fessler
To cite this article: Fessler MB, Jaramillo R, Crockett PW, Zeldin DC. Relationship of serum cholesterol levels to atopy in the US population. Allergy 2010; 65: 859,864. Abstract Background:, Cholesterol promotes Th2 immunity and allergic inflammation in rodents; whether this occurs in humans is unclear. Reports of both direct and inverse associations between serum cholesterol and atopy in different populations suggest that race and/or other demographic variables may modify these relationships. Aims of the study:, To determine the relationships between levels of three serum cholesterol measures [total cholesterol (TC), high density lipoprotein-cholesterol (HDL-C), and non-HDL-C] and atopy in a sample representative of the US population. Methods:, Cross-sectional study of 6854 participants aged ,6 years from the 2005,2006 National Health and Nutrition Examination Survey. Results:, In the overall population, adjusted odds ratios (AORs) per two-standard deviation increase in TC and non-HDL-C for biochemical atopy (defined as ,1 allergen-specific IgE to 19 allergens) were 1.17 [95% confidence interval (CI), 1.00,1.38] and 1.19 (95% CI, 1.03,1.39), respectively. Interactions by race were noted for the two relationships (interaction P = 0.004 and P = 0.009, respectively) with non-Hispanic Whites (NHWs) having direct relationships [TC: AOR 1.27 (95% CI, 1.03,1.57); non-HDL-C: AOR 1.27 (95% CI, 1.03,1.56)] and non-Hispanic Blacks (NHBs) inverse relationships [TC: AOR 0.77 (95% CI, 0.62,0.95); non-HDL-C: AOR 0.86 (95% CI, 0.69,1.08)]. The adjusted HDL-C,atopy relationship was nonsignificant for NHWs and inverse for NHBs [AOR 0.77 (95% CI, 0.61,0.96)]. Relationships were independent of body mass index and serum C-reactive protein and unmodified by corticosteroid or statin usage. Results were similar using current hay fever/allergy as the atopy outcome. Conclusions:, There are marked inter-racial differences in the relationship between serum cholesterol and atopy in the US population. [source]

Analysis of the high affinity IgE receptor genes reveals epistatic effects of FCER1A variants on eczema risk

ALLERGY, Issue 7 2010
J. M. Mahachie John
To cite this article: Mahachie John JM, Baurecht H, Rodríguez E, Naumann A, Wagenpfeil S, Klopp N, Mempel M, Novak N, Bieber T, Wichmann H-E, Ring J, Illig T, Cattaert T, Van Steen K, Weidinger S. Analysis of the high affinity IgE receptor genes reveals epistatic effects of FCER1A variants eczema risk. Allergy 2010; 65: 875,882. Abstract Background:, High levels of total and allergen-specific IgE levels are a key feature in allergic diseases. The high-affinity receptor for IgE, which is composed of one alpha (FCER1A), one beta (FCER1B), and two gamma (FCER1G) subunits, represents the central receptor of IgE-induced reactions. In a genome-wide association scan, we recently identified associations between functional FCER1A variants and total serum IgE levels. Previous studies had reported linkage and association of FCER1B variants with IgE and atopic traits. The FCER1G gene has not yet been investigated with regard to atopy. Filaggrin (FLG) is the strongest known risk gene for eczema, in particular the allergic subtype of eczema. Methods:, We investigated the association of FCER1A, FCER1B, and FCER1G variants with IgE in a large population-based cohort (n = 4261) and tested for epistatic effects using the model-based multifactor dimensionality reduction (MB-MDR) method. In addition, we investigated a potential interaction between FLG and FCER1A variants in a large collection of eczema cases (n = 1018) and population controls. Results:, Three strongly correlated FCER1A polymorphisms were significantly associated with total and specific IgE levels as well as allergic sensitization. No associations were seen for FCER1B and FCER1G. After adjustment for FLG effects, a significant epistatic effect of the FCER1A variants rs10489854 and rs2511211 on eczema risk was detected. Conclusions:, These results suggest that FCER1A variants by themselves and in combination influence IgE levels and act synergistically to influence eczema risk. [source]

International variations in associations of allergic markers and diseases in children: ISAAC Phase Two

ALLERGY, Issue 6 2010
G. Weinmayr
To cite this article: Weinmayr G, Genuneit J, Nagel G, Björkstén B, van Hage M, Priftanji A, Cooper P, Rijkjärv M-A, von Mutius E, Tsanakas J, Forastiere F, Doekes G, Garrido JB, Suarez-Varela MM, Bråbäck L, Strachan DP, the ISAAC Phase Two Study Group. International variations in associations of allergic markers and diseases in children: ISAAC Phase Two. Allergy 2010; 65: 766,775. Abstract Background:, Circulating allergen-specific IgE (sIgE) and skin prick tests (SPT) are used to define atopy. Downregulation of local inflammatory responsiveness has been proposed to explain a low prevalence of positive SPTs in less affluent countries. We analysed the association between SPTs, total and allergen-specific IgE and their relationships to allergic symptoms in centres with diverse living conditions. Methods:, Cross-sectional studies of stratified random samples of 8 to 12-year-old children (n = 7461) used the standardized methodology of Phase Two of the International Study of Asthma and Allergies in Childhood (ISAAC). Symptoms of asthma, rhinitis and eczema were ascertained by parental questionnaires. Skin examination, hypertonic saline bronchial challenge, six aeroallergen SPTs and measurements of serum total IgE and sIgE were performed. Results:, In nonaffluent countries, a higher proportion of children with positive SPT had no detectable sIgE (range 37,61%) than in affluent countries (0,37%). Total serum IgE was associated with all disease outcomes among children with both positive SPT and sIgE (P < 0.001), but only with self-reported eczema in children with negative SPTs and negative sIgE. Conclusions:, The international pattern of discordance between SPT and sIgE results did not support the downregulation hypothesis. Among children with no evidence of sensitization to common aeroallergens, increased total IgE contributes little to the risk of wheeze and rhinitis in the general population but may play a role in eczema. [source]

Allergen provocation increases TH2-cytokines and FOXP3 expression in the asthmatic lung

ALLERGY, Issue 3 2010
S. Thunberg
To cite this article: Thunberg S, Gafvelin G, Nord M, Grönneberg R, Grunewald J, Eklund A, van Hage M. Allergen provocation increases TH2-cytokines and FOXP3 expression in the asthmatic lung. Allergy 2010; 65: 311,318. Abstract Background:, Allergic asthma is caused by allergen-specific IgE and T-helper cell (Th) type 2 responses towards airborne allergens. The objective of this study was to investigate local and systemic regulatory mechanisms in the early asthmatic response to bronchial allergen provocation. Methods:, Birch pollen-allergic patients with mild asthma (n = 13) and healthy nonallergic controls (n = 14) were subjected to bronchoalveolar lavage (BAL) and blood sampling. On patients BAL was performed twice: without preceding provocation (,before samples') and 24 h after bronchial provocation with birch pollen allergen. Lymphocytes in BAL and peripheral blood mononuclear cells (PBMCs) were phenotyped by multi-colour flow cytometry and cytokines measured by cytometric bead array. Proliferation and secreted cytokines were analysed in allergen-stimulated PBMCs, CD25+ depleted PBMCs and PBMCs with IL-10 neutralizing antibodies. Results:, The numbers of CD69+ and FOXP3+ lymphocytes were higher in BAL after compared with before allergen provocation in asthmatic patients. Moreover, allergen provocation increased expression of FOXP3 in CD4+CD25bright cells. The cytokine profile in BAL fluid from asthmatics revealed higher levels of IL-5, compared with the controls, and an increase in IL-5, IL-6, IL-9 and IL-10 after allergen provocation. Pollen allergen stimulated PBMC cultures from asthmatic patients produced elevated levels of IL-5 and IL-13 compared with the controls, which were not affected by depletion of CD25+ cells or IL-10 neutralization. Conclusion:, Despite an increase in CD4+CD25bright cells expressing high levels of FOXP3 in response to bronchial allergen provocation, asthmatic patients exhibit enhanced levels of Th2 cytokines in the lung, which may indicate an inability among infiltrating cells to suppress Th2 responses. [source]

Relationship between pretreatment specific IgE and the response to omalizumab therapy

ALLERGY, Issue 12 2009
U. Wahn
Background:, Omalizumab, an anti-IgE antibody, has proven efficacy in patients with moderate-to-severe and severe persistent allergic (IgE-mediated) asthma. While previous analyses have had some limited success in predicting which patients will gain greatest benefit based on pretreatment baseline characteristics, it remains important to try to improve this predictability. Methods:, Following a run-in phase, patients (12,75 years) inadequately controlled despite current therapy were randomized to receive omalizumab or placebo for 28 weeks in a double-blind, parallel-group, multicenter study (INNOVATE). Univariate analyses were performed to assess whether pretreatment specific IgE serum levels and related variables could be identified that were predictive of a response to omalizumab patients (n = 337) enrolled in INNOVATE. Response was measured via variables including exacerbations, QoL, FEV1 and physicians' overall assessment. Results:, A total of 305 patients (90.5%) were sensitive to more than one allergen and the majority of patients were positive to D1 Dermatophagoides pteronyssinus and D2 Dermatophagoides farinae. Patients with relatively high values of D1 or D2, but with these making a relatively low contribution to total specific IgE load, appeared to attain most benefit from omalizumab. However, no consistent predictive effect for omalizumab response was observed either for total specific IgE or levels of IgEs specific for individual allergens. Conclusions:, Based on these data, pretreatment allergen-specific IgE levels do not provide any better prediction of response to treatment as compared with pretreatment total IgE. At present, the most reliable method of identifying patients who respond to omalizumab treatment remains a physician's assessment. [source]

Longitudinal trends of total and allergen-specific IgE throughout childhood

ALLERGY, Issue 7 2009
P. M. Matricardi
Background:, The development and the quantitative relationship between allergen-specific IgE (S-IgE) responses and total IgE (T-IgE), during childhood and adolescence have not been described and understood in detail. The objective of this study was to describe and compare the longitudinal trends of serum levels of S-IgE and T-IgE during childhood. Methods:, We analysed data from participants in the MAS birth cohort study at 2, 5, 7 and 10 years of age (n = 273) and at 1, 3, 5, 6, 7, 10 and 13 years (n = 84). Total-IgE and the overall level of specific-IgE against nine locally relevant airborne and food allergens were determined by FEIA (ImmunoCAP). Allergic rhino-conjunctivitis and asthma were ascertained by questionnaires. Results:, Longitudinal patterns of T-IgE levels from age 1 to 13 years were highly heterogeneous (declining, flat or increasing with different profiles). From 5 years of age, logarithmic (log10) transformed values of T-IgE and of S-IgE levels tend to follow a parallel trend, so that their relation remained constant throughout school age. A flat trend of T-IgE vs a constantly increasing trend of T-IgE was associated with a low or, respectively, high rate of wheezing at 13 years of age. Conclusions:, Beginning at the age of 5 years, total serum IgE levels in children from an industrialized country evolved in parallel with overall S-IgE levels. Therefore, variations in T-IgE levels at school age closely reflect variations in overall S-IgE levels. Further studies are required to strengthen the biological and clinical implication of this novel finding. [source]

Evidence for allergen-specific IgE of maternal origin in human placenta

ImmunoCAPTM Phadiatop® Infant , a new blood test for detecting IgE sensitisation in children at 2 years of age

ALLERGY, Issue 3 2006
N. Ballardini
Background:, Correct diagnosis of immunoglobulin E (IgE)-mediated disease is the prerequisite for secondary allergy prevention during early childhood. Objective:, To evaluate the diagnostic efficacy of a new blood test, Phadiatop® Infant, in detecting IgE sensitisation to food and inhalant allergens among children at 2 years of age. Methods:, Children (n = 239) were followed prospectively from birth to 2 years of age for the presence of IgE sensitisation and the development of atopic manifestations. Immunoglobulin E sensitisation was evaluated by skin prick test (SPT) and analysis of allergen-specific IgE antibodies in plasma to food and inhalant allergens. The children were classified into three groups: IgE-sensitised, non-IgE sensitised and inconclusive, depending on SPT and allergen-specific IgE results. Results:, Twenty-six (11%) of the children were classified as IgE-sensitised, 182 (76%) as non-IgE sensitised and 31 (13%) as inconclusive. Phadiatop Infant was positive in 50 (21%) of the children. Ten children (4%) with identified IgE antibodies against the selected food and inhalant allergens showed negative Phadiatop Infant. Three children showed positive Phadiatop Infant but were negative in the other tests performed. These results correspond to positive and negative predictive values for Phadiatop Infant of 89 and 99%, respectively. Children with clinical symptoms of atopic diseases had significantly increased levels for Phadiatop Infant (P < 0.01). Conclusion:, Phadiatop Infant appears to be a reliable alternative to SPT and the measurement of allergen-specific IgE antibodies in plasma for detecting clinically important IgE sensitisation among children at 2 years of age. [source]

Comparison of skin barrier function and sensory nerve electric current perception threshold between IgE-high extrinsic and IgE-normal intrinsic types of atopic dermatitis

BRITISH JOURNAL OF DERMATOLOGY, Issue 1 2010
T. Mori
Summary Background, Two types of atopic dermatitis (AD) have been proposed, with different pathophysiological mechanisms underlying this seemingly heterogeneous disorder. The extrinsic type shows high IgE levels presumably as a consequence of skin barrier damage and feasible allergen permeation, whereas the intrinsic type exhibits normal IgE levels and is not mediated by allergen-specific IgE. Objectives, To investigate the relationship between pruritus perception threshold and skin barrier function of patients with AD in a comparison between the extrinsic and intrinsic types. Methods, Enrolled in this study were 32 patients with extrinsic AD, 17 with intrinsic AD and 24 healthy individuals. The barrier function of the stratum corneum was assessed by skin surface hydration and transepidermal water loss (TEWL), and pruritus perception was evaluated by the electric current perception threshold (CPT) of sensory nerves upon neuroselective transcutaneous electric stimulation. Results, Skin surface hydration was significantly lower and TEWL was significantly higher in extrinsic AD than intrinsic AD or normal controls. Although there was no statistically significant difference in CPT among extrinsic AD, intrinsic AD and normal controls, CPT was significantly correlated with skin surface hydration and inversely with TEWL in intrinsic AD and normal controls, but not extrinsic AD. Finally, CPT was correlated with the visual analogue scale of itch in the nonlesional skin of patients with extrinsic but not intrinsic AD. Conclusions, Patients with extrinsic AD have an impaired barrier, which increases the pre-existing pruritus but rather decreases sensitivity to external stimuli. In contrast, patients with intrinsic AD retain a normal barrier function and sensory reactivity to external pruritic stimuli. [source]

Characteristics of extrinsic vs. intrinsic atopic dermatitis in infancy: correlations with laboratory variables

BRITISH JOURNAL OF DERMATOLOGY, Issue 4 2006
J-H. Park
Summary Background, Atopic dermatitis (AD) has been divided into the extrinsic type (ADe) and the intrinsic type (ADi) according to the serum IgE levels and the presence or absence of allergen-specific IgE. Although previous studies have demonstrated differences in the various immunological parameters, the characteristics of AD in infancy have rarely been reported. Objectives, Our study was performed to analyse the correlations between the laboratory parameters of infantile ADe and ADi. Methods, We recruited 237 infants with AD and checked the SCORAD index, the number of peripheral blood eosinophils, the serum eosinophil cationic protein (ECP) levels, the total serum IgE levels and the specific serum IgE levels in all the patients. We also checked the serum interleukin (IL)-4 and IL-5 levels in 20 patients with ADe and in 20 with ADi. Results, This study showed many peculiar characteristics of infantile AD. In infancy, ADi was more prevalent than ADe. The eosinophil count, the ECP level and the SCORAD in ADi were lower than in ADe. Furthermore, a group of patients without characteristics of ADi or ADe could be identified. We tentatively classify this group as indeterminate type (ADind) and propose it as a separate entity. The clinical severity was well correlated with the eosinophil count and the serum ECP levels in ADe and ADi. Therefore these two parameters could be used as clinical severity markers in infancy. Infants are more allergic to food, and the variety of specific allergenic responses was connected with clinical severity. A higher eosinophil count, a higher ECP level and a higher detection rate of IL-5 in the peripheral blood of infants with ADe means that eosinophils have a more prominent role in ADe than in ADi. Conclusions, Infantile AD has many distinctive features in its laboratory variables as compared with AD in other age groups. Clinicians should recognize these facts when they deal with infants with AD, and further studies are warranted on the natural course of infantile AD. [source]

Developments in allergen-specific immunotherapy: from allergen extracts to allergy vaccines bypassing allergen-specific immunoglobulin E and T cell reactivity

CLINICAL & EXPERIMENTAL ALLERGY, Issue 3 2010
M. Focke
Summary Allergen-specific immunotherapy (SIT) is the only specific and disease-modifying approach for the treatment of allergy but several disadvantages have limited its broad applicability. We argue that the majority of the possible disadvantages of SIT such as unwanted effects, poor efficacy and specificity as well as inconvenient application are related to the poor quality of natural allergen extracts, which are the active ingredients of all currently available allergy vaccines. Because of the progress made in the field of molecular allergen characterization, new allergy vaccines based on recombinant allergens, recombinant hypoallergenic allergen derivatives and allergen-derived T cell peptides have entered clinical testing and hold promise to reduce the side-effects and to increase the specificity as well as the efficacy of SIT. Here, we present a refined immunotherapy concept, which is based on the use of peptides derived from allergen surfaces that exhibit reduced, allergen-specific IgE as well as T cell reactivity. These peptides when fused to non-allergenic carriers give rise to allergen-specific protective IgG responses with T cell help from a non-allergenic carrier molecule. We summarize the experimental data demonstrating that such peptide vaccines can bypass allergen-specific IgE as well as T cell activation and may be administered at high doses without IgE- and T cell-mediated side-effects. Should these peptide vaccines prove efficacious and safe in clinical trials, it may become possible to develop convenient, safe and broadly applicable forms of SIT as true alternatives to symptomatic, drug-based allergy treatment. Cite this as: M. Focke, I. Swoboda, K. Marth and R. Valenta, Clinical & Experimental Allergy, 2010 (40) 385,397. [source]

A multi-centre study of candidate genes for wheeze and allergy: the International Study of Asthma and Allergies in Childhood Phase 2

CLINICAL & EXPERIMENTAL ALLERGY, Issue 12 2009
J. Genuneit
Summary Background Common polymorphisms have been identified in genes suspected to play a role in asthma. We investigated their associations with wheeze and allergy in a case,control sample from Phase 2 of the International Study of Asthma and Allergies in Childhood. Methods We compared 1105 wheezing and 3137 non-wheezing children aged 8,12 years from 17 study centres in 13 countries. Genotyping of 55 candidate single nucleotide polymorphisms (SNPs) in 14 genes was performed using the Sequenom System. Logistic regression models were fitted separately for each centre and each SNP. A combined per allele odds ratio and measures of heterogeneity between centres were derived by random effects meta-analysis. Results Significant associations with wheeze in the past year were detected in only four genes (IL4R, TLR4, MS4A2, TLR9, P<0.05), with per allele odds ratios generally <1.3. Variants in IL4R and TLR4 were also related to allergen-specific IgE, while polymorphisms in FCER1B (MS4A2) and TLR9 were not. There were also highly significant associations (P<0.001) between SPINK5 variants and visible eczema (but not IgE levels) and between IL13 variants and total IgE. Heterogeneity of effects across centres was rare, despite differences in allele frequencies. Conclusions Despite the biological plausibility of IgE-related mechanisms in asthma, very few of the tested candidates showed evidence of association with both wheeze and increased IgE levels. We were unable to confirm associations of the positional candidates DPP10 and PHF11 with wheeze, although our study had ample power to detect the expected associations of IL13 variants with IgE and SPINK5 variants with eczema. [source]

Early-life co-administration of cockroach allergen and endotoxin augments pulmonary and systemic responses

CLINICAL & EXPERIMENTAL ALLERGY, Issue 7 2009
K. Kulhankova
Summary Background Environmental exposures to cockroach allergen and endotoxin are recognized epidemiological risk factors for the early development of allergies and asthma in children. Because of this, it is important to examine the role of early-life concurrent inhalation exposures to cockroach allergen and endotoxin in the pathogenesis of allergic airways disease. Objective We examined the effects of repeated concomitant endotoxin and cockroach allergen inhalation on the pulmonary and systemic immune responses of newborn and juvenile mice. Methods C3H/HeBFeJ mice were exposed to inhaled endotoxin and cockroach allergen via intranasal instillation from day 2 to 21 after birth, and systemic and pulmonary responses were examined in serum, bronchoalveolar lavage fluid, and lung tissue. Results Cockroach allergen exposures induced pulmonary eosinophilic inflammation, total and allergen-specific IgE, IgG1, and IgG2a production, and alveolar remodelling. Co-exposures with endotoxin and cockroach allergen significantly increased serum IgE and IgG1, lung inflammation, and alveolar wall thickness, and decreased airspace volume density. Importantly, compared with exposures with individual substances, the responses to co-exposures were more than additive. Conclusions Repeated inhalation exposures of neonatal and juvenile mice to endotoxin and cockroach allergen increased the pulmonary inflammatory and systemic immune responses in a synergistic manner and enhanced alveolar remodelling in the developing lung. These data underscore the importance of evaluating the effect of multiple, concurrent environmental exposures, and of using an experimental model that incorporates clinically relevant timing and route of exposures. [source]

The mast cell and allergic diseases: role in pathogenesis and implications for therapy

CLINICAL & EXPERIMENTAL ALLERGY, Issue 1 2008
J. M. Brown
Summary Mast cells have long been recognized for their role in the genesis of allergic inflammation; and more recently for their participation in innate and acquired immune responses. Mast cells reside within tissues including the skin and mucosal membranes, which interface with the external environment; as well as being found within vascularized tissues next to nerves, blood vessels and glandular structures. Mast cells have the capability of reacting both within minutes and over hours to specific stimuli, with local and systemic effects. Mast cells express the high affinity IgE receptor (Fc,RI) and upon aggregation of Fc,RI by allergen-specific IgE, mast cells release and generate biologically active preformed and newly synthesized mediators which are involved in many aspects of allergic inflammation. While mast cells have been well documented to be essential for acute allergic reactions, more recently the importance of mast cells in reacting through pattern recognition receptors in innate immune responses has become recognized. Moreover, as our molecular understanding of the mast cell has evolved, novel targets for modulation have been identified with promising therapeutic potential. [source]

Poor association between allergen-specific serum immunoglobulin E levels, skin sensitivity and basophil degranulation: a study with recombinant birch pollen allergen Bet v 1 and an immunoglobulin E detection system measuring immunoglobulin E capable of binding to Fc,RI

CLINICAL & EXPERIMENTAL ALLERGY, Issue 2 2005
A. Purohit
Summary Background Results from several studies indicate that the magnitude of immediate symptoms of type I allergy caused by allergen-induced cross-linking of high-affinity Fc, receptors on effector cells (mast cells and basophils) is not always associated with allergen-specific IgE levels. Objective To investigate the association of results from intradermal skin testing, basophil histamine release and allergen-specific IgE, IgG1,4, IgA and IgM antibody levels in a clinical study performed in birch pollen-allergic patients (n=18). Methods rBet v 1-specific IgEs were measured by quantitative CAP measurements and by using purified Fc,RI-derived ,-chain to quantify IgE capable of binding to effector cells. Bet v 1-specific IgG subclasses, IgA and IgM levels were measured by ELISA, and basophil histamine release was determined in whole blood samples. Intradermal skin testing was performed with the end-point titration method. Results Our study demonstrates on the molecular level that the concentrations of allergen-specific IgE antibodies capable of binding to Fc,RI and biological sensitivities are not necessarily associated. A moderate association was found between cutaneous and basophil sensitivity. Conclusion Our results highlight the quantitative discrepancies and limitations of the present diagnostic tools in allergy, even when using a single allergenic molecule. The quantity of allergen-specific serum IgE is only one component of far more complex cellular systems (i.e. basophil-based tests, skin tests) used as indirect diagnostic tests for IgE-mediated allergic sensitivity. [source]

Effects of lysed Enterococcus faecalis FK-23 on allergen-induced serum antibody responses and active cutaneous anaphylaxis in mice

CLINICAL & EXPERIMENTAL ALLERGY, Issue 11 2004
T. Shimada
Summary Background Our previous studies have presented evidence that lysed Enterococcus faecalis FK-23 (LFK), a lysozyme and heat-treated probiotic product, can inhibit allergen-induced local accumulation of eosinophils in mice. Objective The purpose of this experimental study was to evaluate the influence of orally administrated LFK on the host immune responses. Methods BALB/c mice were sensitized subcutaneously, and challenged intraperitoneally by cedar pollen allergen. Blood and spleen samples were collected after oral administration of LFK 60 mg/day for 21 days. The serum levels of total and allergen-specific IgE and IgG2a antibodies and the production of IL-4, IL-5 and IFN-, generated by allergen-stimulated cultured splenocytes were determined. Additionally, the effect of LFK on active cutaneous anaphylaxis (ACA) induced by ovalbumin (OVA) challenge in mice was measured after 28 days LFK treatment. Results No significant differences in serum immunoglobulin levels, as well as in cytokine production of splenocytes were observed between LFK-treated and control mice (P>0.05). There was, however, an increasing tendency of allergen-specific IgG2a level in mice after LFK treatment for 21 days compared with controls (P=0.060). Furthermore, the serum ratio of specific IgE to IgG2a was found to be significantly decreased in the LFK group (P=0.005). In addition, a significant inhibition of OVA-induced ACA reaction was observed in mice that had been fed for 28 days with LFK compared with control mice (P=0.008). Conclusion These results suggest that LFK shows an anti-inflammatory effect, which may be part of the mechanism for protection against IgE-mediated allergy. [source]

HLA DPB1*0201 allele is negatively associated with immunoglobulin E responsiveness specific for house dust mite allergens in Taiwan

CLINICAL & EXPERIMENTAL ALLERGY, Issue 4 2000

Background House dust mite (HDM) Dermatophagoides pteronyssinus is the most important source of indoor allergens that cause allergic diseases in Taiwan. We prepared purified HDM allergens (Der p 1, Der p 2 and Der p 5) to detect allergen-specific immunoglobulin (Ig) E responsiveness among a large number of test subjects. The robust genetic typing system for HLA class II genes also facilitated the study on association of HLA and allergic response toward HDM. Objective This study intended to investigate the association between HLA class II alleles and the IgE responsiveness to the major allergens from HDM, D. pteronyssinus. Methods Two hundred and forty-eight subjects were selected for HLA association study. Plasma HDM allergen (Der p 1, Der p 2, Der p 5) -specific IgE and Der p 2-specific IgG antibodies were detected by ELISA, while HLA class II -DRB1, -DQA1, -DQB1, -DPB1 genetic polymorphism was determined by polymerase chain reaction/sequence-specific oligonucleotide probe hybridization (PCR/SSOPH). Statistical comparison of the allelic distribution of each HLA class II genes among the individuals with/without HDM allergen-specific IgE and IgG antibodies were performed. Results There was no significant association between HLA DRB1, DQB1, DQA1 alleles and HDM-specific IgE responsiveness noted. Only DRB1*0803 and the linked DQA1*0103 alleles showed positive association with Der p 5-specific IgE responsiveness. However, we found that HLA-DPB1*1301 predisposed subjects to IgE responsiveness to HDM Der p 5. HLA DPB1*0501 was weakly associated with the IgE responsiveness to HDM Der p 1 and Der p 5. There was a strong negative association between the HLA-DPB1*0201 allele with IgE responsiveness to Der p 1 (OR: 0.30, P , 0.0001, P , 0.0007, Pc , 0.010). Conclusion We clearly observed the association between HLA DPB1 alleles and specific IgE responsiveness to HDM major allergens. The molecular mechanism of HLA-DPB1*0201 involvement in protecting subjects from HDM-specific IgE responsiveness awaits further investigation. [source]

Airway eosinophilia is not a requirement for allergen-induced airway hyperresponsiveness

CLINICAL & EXPERIMENTAL ALLERGY, Issue 1 2000
Tournoy
Background House dust mites (HDMs) are the major source of perennial allergens causing human allergic asthma. Animal models mimicking as closely as possible the allergic features observed in human asthma are therefore interesting tools for studying the immunological and pathophysiological mechanisms involved. Especially the role of eosinophils and allergen-specific immunoglobulin (Ig) E in the pathophysiology of airway hyperresponsiveness (AHR) remains a subject of intense debate. Objective To develop a mouse model of allergic airway inflammation and hyperresponsiveness based on the use of purified house dust mite allergen (Der p 1) as clinical relevant allergen. Furthermore, we studied the effects of low dose allergen exposure on the airway eosinophilia and AHR. Methods On day 0, C57Bl/6 mice were immunized with purified Der p 1 intraperitoneally. From day 14,20, the mice were exposed daily to a 30-min aerosol of different concentrations of house dust mite extract. Results Mice, actively immunized with Der p 1 and subsequently exposed to HDM aerosols, developed AHR, eosinophil infiltration of the airways and allergen-specific IgE. Moreover, lowering the concentration of the HDM aerosol also induced AHR and IgE without apparent eosinophil influx into the airways. Der p 1-sensitized mice exposed to PBS produced IgE, but did not show AHR or eosinophil influx. Conclusion This in vivo model of HDM-induced allergic airway changes suggests that AHR is not related to either eosinophil influx or allergen-specific serum IgE, thereby reducing the importance of these factors as essential elements for allergic AHR. [source]