Mite-allergic Asthmatic Patients Research Articles

A pilot study on the allergen-specific IgE to molecular components on polysensitized mite allergic asthmatic patients in Guangzhou, China

ObjectiveUsing multiplex microarray-based component resolved diagnosis (CRD) to investigate the allergen sensitization profile of allergic asthma patients in southern China. MethodSerum samples from 57 polysensitized mite allergic asthmatic patients in a tertiary referral centre of southern China were tested with multiplex CRD (ISAC) for specific immunoglobulin E (sIgE) against 112 single allergen and components. Result was then compared with those from singleplex ImmunoCAP. ResultsWith ISAC, the highest sensitization was seen for nDer f 1 (71.9%), rDer f 2 (73.7%), nDer p 1 (70.2%) and rDer p 2 (66.7%), whereas rDer p 10 and other storage mites’ components only showed 10% positivity. rFel d 1 and rCan f 1 were found positive in 29.8% and 14.0% samples respectively. Other epithelia components had less than 7.0% positive rate. Sensitization to pollen components was dominated by nCyn d 1 (17.5%) and nPhl p 4 (12.3%), Carbohydrate cross-reactive determinants (CCD) was positive in 4 patients who were also positive to nPhl p 4, nCyn d 1 and rPla a 2, and all of them have combined asthma and rhinitis. The sensitivity to mold (rAsp f 3), cockroach (nBla g 7) and Anisakis simplex component (rAni s 3) were all the same at 8.8%. 93.0% patients were sensitive to more than one component, with more than half of them (57.9%) positive to five or more components.Patients with combined asthma and rhinitis (AA + AR) were sensitive to more components than those with asthma only (AA). Positive rate to nPhl p 4 was significantly higher in patients with AA + AR than with AA only (χ2 = 4.31, P = 0.038).Compared with ImmunoCAP, ISAC showed a similar high detection rate for D. pteronyssinus and D. farinae, but only 10.0% of B. tropicalis sensitive patients were positive to rBlo t 5. Optimal scale analysis on correlation of allergens components showed rDer p 10 was associated to food allergy. ConclusionBeing the first multiplex microarray based CRD study on southern Chinese, ISAC showed house dust mites components were the major allergen components led to sensitization in asthmatic patients. Patients with combined AA + AR were sensitive to more components than those with AA only. Other components with higher positive rate include pollen components nCyn d 1, nPhl P 4 and animal dander components rFel d 1 and rCan f 1. For B. tropicalis, the rBlo t 5 in ISAC may not represent the major Blomia component in southern Chinese patients.

Association between total immunoglobulin E and antibody responses to naturally acquired Ascaris lumbricoides infection and polymorphisms of immune system-related LIG4, TNFSF13B and IRS2 genes

The 13q33-34 region harbours a susceptibility locus to Ascaris lumbricoides, although the underlying genes are unknown. Immunoglobulin (Ig)E and IgG confer protective immunity and here we sought to investigate in an endemic population whether LIG4, TNFSF13B and IRS2 genes influence IgE and IgG levels against Ascaris and the ABA-1 allergen as a putative resistance marker. Mite-allergic asthmatic patients were analysed for potential relationships between Ascaris predisposition and allergy. One thousand and sixty-four subjects from Cartagena, Colombia, were included. Single nucleotide polymorphisms (SNPs) were genotyped using TaqMan assays. Antibody levels were measured by enzyme-linked immunosorbent assay. Linear and logistic regressions were used to model effects of genotypes on antibody levels. The GG genotype of LIG4 (rs1805388) was associated with higher IgE levels to Ascaris compared with other genotypes. TNFSF13B (rs10508198) was associated positively with IgG levels against Ascaris extract and IgE levels against ABA-1. In asthmatics, IRS2 (rs2289046) was associated with high total IgE levels. Associations held up after correction by population stratification using a set of 52 ancestry markers, age, sex and disease status. There was no association with asthma or mite sensitization. In a tropical population, LIG4 and TNFSF13B polymorphisms are associated with specific IgE and IgG to Ascaris, supporting previous linkage studies implicating the 13q33 region. Our results suggest that genes protecting against parasite infections can be different to those predisposing to asthma and atopy.

Consultation and referral guidelines citing the evidence: How the allergist-immunologist can help

Consultation and referral guidelines citing the evidence: How the allergist-immunologist can help

Evaluation of BGC administration as an adjuvant to specific immunotherapy in mite-allergic asthmatic patients

RATIONALE: Effects of mycobacteria in prevention or reversion of Th2-type responses have been demonstrated in experimental models. We investigated whether BCG vaccination in conjunction to specific immunotherapy (SIT) promotes additional benefits.

Dust mite allergens: mitigation and control.

In recent years, greater attention has been given to the role of indoor allergens as a cause of sensitization and allergic respiratory diseases. Although indoor allergen control measures to reduce symptoms in individuals allergic to mites have produced controversial results, environmental allergen avoidance is today one of the four primary goals of asthma management recommended in several guidelines of asthma treatment. Exposure to high indoor aeroallergen levels, especially to house dust mite allergens, is an important environmental risk factor for allergic sensitization and the subsequent development and exacerbation of asthma. Therefore, effective aeroallergen avoidance is of use to prevent and treat allergic diseases. Although endotoxin exposure may be protective in early life, it has been demonstrated that the inhalation of endotoxin may exacerbate asthma in house dust mite sensitized patients. Mite-allergic asthmatic patients should be aware of the dangerous combination of mite allergen exposure associated with high endotoxin levels in house dust. These two immunologically active substances have been associated with severe asthma and seasonal exacerbation of symptoms. Effective house dust mite allergen avoidance will never be achieved using a single control measure; various methods are required to affect the multiple factors that facilitate high indoor allergen levels. Education of the patients and their families is also an important component of environmental control strategies.

T-cell epitope analysis of Mag 3, an important allergen from the house dust mite, Dermatophagoides farinae

Here we describe the detection of T-cell epitope region on the house dust mite allergen Mag 3, which has been shown to trigger T-cell proliferation in mite-allergic asthmatic patients. We first examined murine T-cell epitope using T-cell fraction prepared from recombinant Mag 3 (r-Mag 3)-primed H-2 k mice. Initial proliferation assay with truncated r-Mag 3 indicated that N-terminal 113 amino acid region was required for triggering T-cell activation. Subsequent epitope scanning with synthetic overlapping peptides revealed that T-cell reactive region was assigned within amino acid range 56–75. We also explored human T-cell determinant using specific T-cells from mite-allergic patients. Intriguingly, we found that amino acid range 56–85, a portion partially overlapping with that identified in r-Mag 3-primed mice, was exclusively recognized by T-cells from different patients. Further investigation of unique T-cell epitope region found in this study would provide insight into the development of animal therapeutic model and/or peptide vaccine for asthma.

Allergy to house dust mite and snails: A model of cross-reaction between food and inhalant allergens with a clinical impact

A knowledge of cross-reactions between different allergens can facilitate the diagnosis of allergy. IgE cross-reactivity has been identified between house dust mite and snails. While most patients have mild symptoms, asthma and/or anaphylaxis may occur with these and other cross-reacting foods. It may be worthwhile to include measurement of IgE to some edible invertebrate animals in asthmatics, e.g. in mite allergic asthmatic patients who eat snails.

163 Clinical study of bedding covers in mite-allergic asthmatic patients

163 Clinical study of bedding covers in mite-allergic asthmatic patients

Possible involvement of mononuclear cells stimulated with specific allergen from asthmatic patients in ICAM-1 expression on the eosinophilic cell line

Adhesion molecules, particularly intercellular adhesion molecule-1 (ICAM-1), recently have been considered to play a key role in inflammatory processes in asthma. Thus, from the point of view of cell interactions between mononuclear cells and eosinophils, we examined whether the supernatant of mononuclear cells (MNC) obtained from mite-allergic asthmatic patients cultured with specific allergen is involved in ICAM-1 expression using an eosinophilic cell line (EoL). ICAM-1 expression was induced by the supernatant of MNC from mite-allergic asthmatic patients stimulated with mite allergen as well as by a combination of IL-3, GM-CSF, and IL-5. Thus, we could conclude that some cytokines produced by specific allergen-stimulated MNC in asthmatics might be involved in allergic inflammation through the induction of adhesion molecule expression such as ICAM-1 on eosinophils in asthma or allergic disorders.

Induction of beta 2 integrin expression on an eosinophilic cell line (EoL-1) by the supernatant of mononuclear cells stimulated with specific allergen from asthmatic patients.

Adhesion molecules recently have been considered to play an important role in inflammatory processes in bronchial asthma. Our previous study revealed high expression of beta 2-integrin family (CR3, LFA-1 alpha, CD18) on hypodense eosinophils. Thus, from the point of view of cell-to-cell interaction between mononuclear cells and eosinophils, we examined whether the supernatant of mononuclear cells obtained from mite-allergic asthmatic patients cultured with specific allergen mite-allergen is involved in adhesion molecule expression using an eosinophilic cell line (EoL-1). These characteristics of beta 2-integrin family expression (high expression of beta 2 integrin) were induced by the supernatant of mononuclear cells from mite-allergic asthmatic patients stimulated with mite-allergen as well as with a combination of the recombinant eosinophilopoietic growth cytokines (IL-3, GM-CSF and IL-5). Thus, we could conclude that some cytokines produced by specific allergen stimulated mononuclear cells in asthmatics might be involved in allergic inflammation through the induction of adhesion molecule expression on eosinophils in asthma or allergic disorders.

Induction of expression of adhesion molecules on an eosinophilic cell line (EoL-1) by the supernatant of lymphocytes stimulated with specific allergen from asthmatic patients.

Recently, adhesion molecules have been considered to play an important role in inflammatory processes in bronchial asthma. To extend our understanding of the high-intensity expression of adhesion molecules (CR3, LFA-1 alpha, LFA-1 beta, ICAM-1) on hypodense eosinophils, which was observed in our previous study, we examined whether the supernatant of lymphocytes from mite-allergic asthmatic patients is involved in adhesion molecule expression using an eosinophilic cell line (EoL-1). These characteristics of adhesion molecule expression were induced by the supernatant of lymphocytes obtained from mite-allergic asthmatic patients cultured with specific allergen as well as a combination of recombinant cytokines (IL-3, GM-CSF, IL-5). Thus, we could conclude that some lymphokines produced by specific allergen in asthma might be involved in the high-intensity expression of adhesion molecules on hypodense eosinophils in asthma or allergic disorders.

Medication requirements and house dust mite exposure in mite‐sensitive asthmatics

To better understand the clinical consequences of exposure to house dust mites (HDM), we investigated the relationship between treatment requirements to control symptoms in mite-allergic asthmatic patients and HDM-allergenic levels in their mattresses. This study included 49 asthmatic subjects recruited from an outpatient clinic. The protocol consisted of a questionnaire about the number of asthma attacks and treatment requirements in the last 3 months. Patients provided a sample of house dust collected from their mattresses by a standardized vacuum cleaning procedure. Mean antigen P1 equivalent defined as the sum of major allergens Der pI and Der fI (Ag P1 Eq) level was 1.34 micrograms/g dust in patients who had no treatment, 5.4 micrograms/g dust in patients who took puffs of beta 2-agonists only when required and 17.8 micrograms/g dust in patients who required daily long-term treatment. Similar relationships were demonstrated between mean Ag P1 Eq levels and the number of asthma attacks. These data support the clinical role of allergenic exposure in HDM-allergic asthmatics.