Major Allergens Of Dermatophagoides Pteronyssinus Research Articles

Allergy to Der p 23 influences the cytokine profile in patients with allergic asthma – a preliminary study

Objective Der p 23 is a major allergen of Dermatophagoides pteronyssinus, which could contribute to allergic asthma. The study compared the cytokine profile (Il-1beta, Il-4, Il-5, Il-6, Il-13, Il-17, TNF-alpha) in patients with allergic asthma, with confirmed allergy to D. pteronyssinus and with the presence or absence of allergy to Der p 23. Methods Among 173 included patients, the following combinations were analyzed: profile A – Der p 1 (+), Der p 2 (+), and Der p 23 (−) observed in 38 (22%) patients; profile B – Der p 1 (+), Der p 2 (+), and Der p 23 (+) in 87 (50.3%) patients; and profile C – Der p 1 (−), Der p 2 (−), and Der p 23 (+) in 15 (8.7%) patients. Results The mean concentration of Il-1beta was significantly lower in profile A than in profiles B and C: 10.51 ± 5.22 (pg/ml) vs. 21.92 ± 11.34 vs. 23.1 ± 8.56 (A vs. B for p = 0.03 and A vs. C for p = 0.019). Similar trends were observed for Il-5: 38.5 ± 10.45 (pg/ml) vs. 94.8 ± 54.11 vs. 103.61 ± 34.9 (A vs. B for p = 0.008 and A vs. C for p = 0.001). Conclusion The higher Il-1 and Il-5 activities observed in profiles B and C with Der p 23 (+) could be responsible for the more effective acceleration of allergic inflammation than in profile A with Der p 23.

Underestimation of house dust mite–specific IgE with extract-based ImmunoCAPs compared with molecular ImmunoCAPs

Underestimation of house dust mite–specific IgE with extract-based ImmunoCAPs compared with molecular ImmunoCAPs

Influence of Interleukin-4 and Interleukin-13 on serum immunoglobulin E in house dust mite allergy

Background Th2 cells are the central mediators of the allergic immune response, as their activation induces it by cytokine release. The key cytokines expressed by Th2 cells and involved in the pathogenesis of allergic airway inflammation and immunoglobulin E (IgE) production are interleukin-4 (IL-4), IL-5, IL-10 and IL-13. The aim of study was to evaluate the in vitro effect of Der p 1, the major allergen of Dermatophagoides pteronyssinus (house dust mite, HDM), on IL-4 and IL-13 production by naive CD4+ T cells cocultured with dendritic cells (DCs) from HDM allergic patients, as well as their influence on serum IgE levels.

Identification of Der p 23, a Peritrophin-Like Protein, As a New Major Dermatophagoides Pteronyssinus Allergen Associated with the Peritrophic Matrix of Mite Fecal Pellets

Identification of Der p 23, a Peritrophin-Like Protein, As a New Major Dermatophagoides Pteronyssinus Allergen Associated with the Peritrophic Matrix of Mite Fecal Pellets

Carrier‐bound nonallergenic Der p 2 peptides induce IgG antibodies blocking allergen‐induced basophil activation in allergic patients

More than 90% of house dust mite-allergic patients are sensitized to the major Dermatophagoides pteronyssinus allergen, Der p 2. The aim of this study was to develop and characterize an allergy vaccine based on carrier-bound Der p 2 peptides, which should allow reducing IgE- and T-cell-mediated side-effects during specific immunotherapy (SIT). Five Der p 2 peptides (P1-P5) were synthesized and analyzed regarding IgE reactivity and allergenic activity. Lymphoproliferative and cytokine responses induced with Der p 2 and Der p 2 peptides were determined in peripheral blood mononuclear cells from mite-allergic patients. Der p 2-specific IgG antibodies induced with carrier-bound Der p 2 peptides in mice and rabbits were tested for their capacity to inhibit IgE binding and basophil activation in allergic patients. Of five overlapping peptides (P1-P5) covering the Der p 2 sequence, two peptides (P2 and P4) were identified, which showed no relevant IgE reactivity, allergenic activity, and induced lower Der p 2-specific T-cell activation than Der p 2. However, when coupled to a carrier, P2 and P4 induced Der p 2-specific IgG antibodies in animals, which inhibited allergic patients' IgE binding to the allergen and allergen-induced basophil activation similar as antibodies induced with Der p 2. Carrier-bound Der p 2 peptides should allow avoiding IgE-mediated side-effects, and because of their low potential to activate allergen-specific T cells, they may reduce late-phase side-effects during SIT. Further, these peptides may be also useful for prophylactic vaccination.

Determinants of House Dust Mite Allergenicity

Results: The studies summarized here show that quantitative measurements of allergen panels provide a better assessment of total anti-mite IgE than assays with mite extracts, and that major allergen Der p 1 induced correspondingly higher T helper cell type 2 (Th2) and Th1 cytokine responses than subordinate allergens Der p 5 and 7. The importance of the knowledge of variants of the major allergens is presented as well recent advances in the characterization of the molecules. Conclusions: Der p 1 and Der p 2 are major allergens of Dermatophagoides pteronyssinus. The minor allergens, however, constitute 50% of the IgE binding and the use of a panel of allergens provides a better measure of house dust mite allergy than IgE binding to extracts. The minor allergens will also be important for studying the immunoregulatory pathways that lead to high and low allergenicity.

Positive association between HLA-DRB1*07 and specific IgE responses to purified major allergens of D. pteronyssinus (Der p 1 and Der p 2)

Human leukocyte antigen (HLA) class II gene products are involved in the antigen presentation of exogenous antigens. The aim of this study was to evaluate whether specific immunoglobulin (Ig)E responses to purified major allergens of Dermatophagoides pteronyssinus (Der p 1 and Der p 2) were associated with genotypes of HLA-DRB1 alleles. Peripheral venous blood samples were collected from two groups of unrelated Korean adolescents: 168 subjects with positive skin response (wheal > or = 3 mm) to crude D. pteronyssinus allergens and 94 age-matched controls with negative skin response and low serum-specific IgE to crude D. pteronyssinus allergens. The former group was found to contain 104 with high serum-specific IgE to crude D. pteronyssinus allergens, 100 with high serum-specific IgE to Der p 1, and 122 with high serum-specific IgE to Der p 2. Genotypes of the HLA-DRB1 alleles were determined using polymerase chain reaction-sequence specific oligonucleotide probes. HLA-DRB1*07 was significantly higher in subjects with a high serum-specific IgE response to crude D. pteronyssinus allergens than the controls (16.3% vs 3.2%, odds ratio [OR] = 5.93, corrected P [Pc] = 0.02). The excess of DRB1*07 was more marked in those with high serum-specific IgE responses to Der p 1 or Der p 2 than the controls (20.0% vs 3.2%, OR = 7.58, Pc = 0.004; 18.9% vs 3.2%, OR = 7.05, Pc = 0.006). Among subjects with high serum IgE to Der p 1, DRB1*13 significantly increased than the controls (32.0% vs 13.8%, OR = 2.93, Pc = 0.03). We clearly observed the association between HLA-DRB1 alleles and specific IgE responsiveness to D. pteronyssinus major allergens. The molecular mechanism of HLA-DRB1*07 and DRB1*13 involvement in D. pteronyssinus-specific IgE responsiveness awaits further investigation.

What drives the allergic march?

What drives the allergic march?

1057 A very sensitive reverse ELISA for measuring specific IgE to major dermatophagoides pteronyssinus allergen, Der p 2

1057 A very sensitive reverse ELISA for measuring specific IgE to major dermatophagoides pteronyssinus allergen, Der p 2

Inverse correlation of domestic exposure to Dermatophagoides pteronyssinus antigen patch test reactivity in patients with atopic dermatitis.

In recent years considerable interest in the pathogenetic role of aeroallergens exacerbating atopic dermatitis (AD) has emerged. The 'atopy patch test' with aeroallergens was introduced by Platts-Mills et al. as an experimental model and as a diagnostic tool. However, its relevance for the clinical manifestation of AD is still not clear. We asked whether there is a relationship between the individual antigen exposure to the major allergen of Dermatophagoides pteronyssinus (Der p 1) and the immunological markers of sensitization to Der p 1 or the clinical severity of AD. We investigated 92 patients with moderate to severe AD. For clinical evaluation the SCORAD severity score was used. Patch tests were performed with purified Der p 1. Specific IgE was measured by a commercial assay. Der p 1 exposure was quantified in a sample of the patient's mattress dust by using a commercial ELISA. No correlation between SCORAD, Der p 1 exposure and RAST could be established. However, there was an unexpected significant inverse correlation between the quantity of mite antigen in the mattress dust and patch test reactivity. Patients with a high antigen load (> 25 microg/g) mostly had a negative patch test. Also, when Der p 1 was correlated to the mattress area (m2) in this group all patch tests were negative. A possible explanation could be that continuous exposure of the skin to house dust mite allergen Der p 1 may induce a down-regulation of the skin immune system of patients with AD. Although the mechanism of this phenomenon is presently unknown, our study shows that a positive allergen patch test alone should not be an indication to undertake allergen exclusion measures in AD patients.

Monoclonal antibodies to recombinant Der p 2, a major house dust mite allergen: specificity, epitope analysis and development of two-site capture ELISA.

House dust mite allergens have been well established as sensitizing agents that are important in the induction of allergic diseases. In order to analyze epitopes of the allergen and to develop a quantitative method of the allergen exposure, monoclonal antibodies against a recombinant Der p 2 (rDer p 2), one of the major allergens of Dermatophagoides pteronyssinus, were produced. Four monoclonal antibodies produced were species-specific and did not cross-react to the D. farinae crude extract. Two of the monoclonal antibodies were found to be IgG1 and the others were IgM. For the analysis of epitopes, a Der p 2 cDNA encoding 126 amino acids (aa) was dissected into three fragments with several overlapping peptides. A (aa residues 1-49), B (44-93), and C fragment (84-126). Three monoclonal antibodies showed reactivities to the recombinant B fragment and to the full-length rDer p 2, but one monoclonal antibody reacted only with the full-length rDer p 2. Two-site capture ELISA was developed using two different monoclonal antibodies for quantitating Der p 2 in house dust. The sensitivity limit was 4 ng/ml with rDer p 2 and 8 micrograms/ml with the D. pteronyssinus crude extract. The result suggested that the assay using monoclonal antibodies against rDer p 2 could be useful for the environmental studies and for the standardization of mite allergen extracts.

Variability of House Dust Mite Allergen Exposure in Dwellings

The variability of repeated house dust mite (HDM) allergen determinations at the same site within 3-24 months was evaluated on previously collected samples. Between two and four repeated measurements of Der p 1, a major allergen of Dermatophagoides pteronyssinus and Der f 1, a major allergen of D. farinae, on 46 carpets and 31 mattresses were analyzed. In 90% of carpets and mattresses, HDM allergen concentrations were clinically relevant (at least one measurement >0.1 microg Der p 1 + Der f 1/g dust). The coefficients of variation (CVs) for allergen concentrations in repeated samples over time (55.3-82.0% for the two allergens in beds and carpets) were clearly greater than the CVs for multiple samples collected at the same time (4.0-32.6%). Determination of allergen mass per square meter of surface instead of concentration per gram of dust resulted in an even greater CV (72.3-86.7%). The 95% range of expected values was about 10-fold above and below the result of a single determination. We conclude that single determinations of HDM allergen in dust give very limited information about long-term exposure of an individual to the allergen. Repeated measurements are recommended. Studies of factors that affect HDM allergen exposure must be planned with appropriate sample sizes.

Bronchial allergen challenge with isolated major allergens of Dermatophagoides pteronyssinus: The role of patient characteristics in the early asthmatic response

Background: The use of allergen extracts will hamper studies into quantitative aspects of allergic responses because the precise amount of relevant allergen for each patient is unknown. Objective: We applied isolated IgE-binding components (major allergens) in the technique of bronchial allergen challenge to determine the role of patient characteristics in the early asthmatic response (EAR). Methods: In 30 patients with mild-to-moderate asthma, the EAR was investigated after inhalation of an isolated major allergen of Dermatophagoides pteronyssinus (i.e., Der p 1 [ n = 16] or Der p 2 [ n = 14]). The degree of early-phase bronchial responsiveness to allergen (the cumulated dose of allergen causing a 20% fall in FEV 1 [PD 20allergen]) was related to the degree of nonspecific bronchial responsiveness (the concentration of histamine causing a 20% fall in FEV 1 [PC 20histamine]) and the level of specific IgE or allergen thresholds as found in skin tests and basophil histamine release assays. Results: Twenty-seven patients with an immediate response during allergen and histamine challenges (ΔFEV 1 , ≥20%) were analyzed. In these patients, a strong correlation was found between PD 20 allergen and PC 20 histamine ( r = 0.81, p < 0.001). Weak correlations were found between PD 20 allergen and the level of specific IgE ( r = –0.36, p = 0.07) or allergen thresholds as found in skin tests (skin prick test, r = 0.36 and p = 0.07; intracutaneous test, r = 0.49 and p = 0.01) or basophil histamine release assays ( r = 0.37, p = 0.08). Moreover, no significant contribution of these indices of IgE-mediated hypersensitivity to the prediction of PD 20 allergen by multilinear regression models with PC 20 histamine was found. Conclusion: In asthmatic patients allergic to house dust mites the degree of nonspecific bronchial hyperresponsiveness is the main determinant of early-phase bronchial responsiveness to allergen. In these patients the degree of allergic sensitivity does not contribute to the prediction of the EAR after allergen inhalation. (J Allergy Clin Immunol 1998;102:24-31.)

Sequence polymorphisms of the Der p 3 house dust mite allergen

The trypsin-like protein Der p 3 is a major allergen of Dermatophagoides pteronyssinus. Like other vertebrate and invertebrate trypsin-like molecules, isoelectric-focusing studies with the natural Der p 3 protein have indicated that several isoforms exist. To determine the extent of the sequence variation of the Der p 3 allergen and distinguish at the molecular level, whether the sequence isoforms represent allelic variants or multiple genes of the allergen. Five cDNA clones of Der p 3 have been isolated from a lambda gt10 D. pteronyssinus library, using a radiolabelled polymerase chain reaction (PCR) Der p 3 P3WS1 probe and sequenced. Southern blot and inverse PCR analysis of Eco R1 digested genomic DNA was performed. Southern blot analysis of Eco R1 digested genomic DNA showed that the DNA encoding Der p 3 was located on a single 3.5 kb fragment and inverse polymerase chain reaction analysis (PCR) of this DNA showed that there was only a single Der p 3 gene on this 3.5 kb fragment. The nucleotide sequence of one of the clones was identical to the original Der p 3 P3WS1 clone and two clones differed only in their 3' untranslated sequences. The other two contained nucleotide changes which lead to several substitutions at the amino acid level, both conservative and non conservative. Clone 3 had 98.7% identity with Der p 3 P3WS1. One clone for which the full sequence was not available (clone 4) had only 84.4% identity with the original clone and is therefore consistent with an isoallergen. These data along with our previous genomic sequence shows that for the most part, the Der p 3 allergen has only minor sequence variations (variants) although the isoallergen indicated by clone 4 needs further investigation. It is now evident that Der p 3 is encoded by a single gene and that most cDNA clones constructed from commercial mites show only minor sequence variation similar to that observed for the group 1 and group 2 house dust mite allergens.

IgE and IgG 4 antibodies from patients with mite allergy recognize different epitopes of Dermatophagoides pteronyssinusgroup II antigen (Der p 2)

BACKGROUND: Der p 2, composed of 129 amino acids, is one of the major allergens of Dermatophagoides pteronyssinus . Several groups reported epitope mapping of IgE antibody but not of IgG or IgG subclass antibodies in Der p 2. OBJECTIVE: The purpose of this study was to compare the epitopes recognized by Der p 2–specific IgE antibodies with those recognized by IgG 4 antibodies. METHODS: Recombinant fusion proteins containing a full-length peptide or overlapping five fragments of Der p 2 were prepared and analyzed for their reactivity with IgE and IgG subclass antibodies in sera from patients with mite allergy by means of Western blot procedure. RESULTS: IgE antibodies in 12 of 13 sera tested bound to full-length Der p 2 (1-129). In 11 of these 12 sera, IgE antibodies bound to one or more of fragments 41-80, 64-105, or 81-129 but not to those of 1-40 or 20-63. Of the 11 sera in which the IgE antibodies to the fragments were detected, only four contained detectable levels of IgG 4 antibodies reactive to the fragments. The binding spectra of the IgG 4 antibodies against the fragments were rather wide and differed from those of IgE antibodies. CONCLUSION: Results revealed that there are differences in epitope recognition between IgE and IgG 4 antibodies; IgE antibodies recognize restricted parts of Der p 2 antigen compared with IgG 4. (J A LLERGY C LIN I MMUNOL 1996;97:638-45.)

Epitope analysis of HLA‐DR‐restricted helper T‐cell responses to Der p II, a major allergen molecule of Dermatophagoides pteronyssinus

T-cell epitopes of Der p II, a major allergen of Dermatophagoides pteronyssinus, were analyzed by using human T-cell clones. We tested 38 cloned T cells from two Japanese patients with allergic rhinitis, and identified at least two peptides (K33-T47 and I58-C73) as helper T-cell epitopes. The former epitope was shown to be restricted by HLA-DRB1*1502, and the latter by HLA-DRB1*0405, both of which are typical Japanese HLA-DR alleles, suggesting that those T-cell epitopes might be important for the onset of house-dust mite allergy in the Japanese population. We prepared 15 analog peptides of the HLA- DRB1*1502-restricted 15-mer peptide. Of those 15 residues, five (F35, L37, A39, F41, and E42) were critical for the epitope activity, and three residues (F35, A39, and E42) seemed to be included in anchor motifs for HLA-DRB1*1502. The epitope peptide was also recognized by HLA-DRB1*1502-positive healthy donors; however, only allergic T cells showed Th2 functions. Antigen-presenting cells of nonallergic donors were able to activate allergic T cells to express Th2 function. This seemed to suggest that antigen recognition of T cells, as well as additional unknown factors which promote Th2, rather than Th1, responses, might be important for the onset of house-dust mite allergy.

610 IgE antibodies cross-reaction between Der p1, the major allergen of Dermatophagoides pteronyssinus and Ananain, a cysteine proteinase from Ananas comosus, the pineapple plant

610 IgE antibodies cross-reaction between Der p1, the major allergen of Dermatophagoides pteronyssinus and Ananain, a cysteine proteinase from Ananas comosus, the pineapple plant

Relationship between exposure to dust mite allergen and bronchial response to exercise in schoolchildren sensitized to dust mites.

We assessed the relationship between the exposure to dust mite allergens and a bronchial response to exercise in 8-year-old schoolchildren. Dust was collected from the mattresses of 1,291 children and the concentration of mite allergens was estimated by a commercially available ELISA test using monoclonal antibodies (ALK, Copenhagen) against the major allergens of Dermatophagoides pteronyssinus (Der pt) and Dermatophagoides farinae (Der f). A positive bronchial response to exercise (decrease of peak expiratory flow > or = 15% after exercise) occurred in 21 (22.6%) of 101 children sensitized to mite allergens (wheal size > or = 4 mm) and in 51 (4.8%) of 1,070 nonsensitized children. In the highest exposure groups (> 10 micrograms allergen/g dust), 15% of children sensitized to Der f and 20% of children sensitized to Der pt were responsive to exercise. Corresponding figures for the lowest exposure groups (< 0.4 micrograms allergen/g dust) were 11 and 28%, respectively. This negative finding may indicate that measurement of allergen concentration in mattresses does not reflect true exposure or alternatively that at the age of 8 years high exposure to dust mite allergens does not affect bronchial response to exercise in sensitized children.

Specific histamine release capacity of peptides selected from the modelized der P I protein, a major allergen of Dermatophagoides pteronyssinus

Dust mite allergens are considered as a major cause of allergic disease and as a risk factor for asthma. Der p I, a 222 amino-acid residue globular glycoprotein, is one of the major allergens from Dermatophagoides pteronyssinus (Dpt) mites. In this study, we have used predictive conventional algorithms (i.e. hydrophilicity, mobility, accessibility) and a three-dimensional model of Der p I derived from comparison to actinidin and papain to select continuous amino acid sequences as potential B cell epitopes. Four peptides, 52–71, 117–133, 176–187, 188–199 were synthesized. Their antigenic reactivity was investigated, mainly by measuring their capacity to induce in vitro histamine release. Results indicated that only Dpt-sensitive patients react specifically to Der p I-derived peptides and more frequently to 52–71 and 117–133. For each peptide, the intensity of response was dependent on the patient tested and on the peptide concn. The capacity of peptides to induce histamine release was demonstrated to be correlated with the serum level of anti-Der p I IgE ( r = 0.86; p < 10 −2). Taken together these data emphasize, in Dpt-sensitive patients, the heterogeneity of the specific response to synthetic Der p I-derived peptides and underline the possible variety of epitopes belonging to the allergen Der p I.

Prevalence of specific IgE to the storage mite, Aleuroglyphus ovatus

Aleuroglyphus ovatus (Ao) is a storage mite that has a worldwide distribution and has been found in stored bran, wheat, chicken meal, and dried fish products. Ao was isolated from a chicken meal sample, cultured on whole wheat flour at 75% relative humidity, and 1 gm of pure Ao bodies were extracted, 1:20 wt/vol, in 0.2 mol/L of ammonium bicarbonate. Der p I, major allergen of Dermatophagoides pteronyssinus (Dp), or Der f I, major allergen to Dermatophagoides farinae (Df), was not detected in extracts of Ao. Sodium dodecyl sulfate—polyacrylamide gel electrophoresis revealed 25 bands (6 to 110 kd), and thin-layer isoelectric focusing revealed 19 bands (isoelectric point, 3.5 to 9.3). Sodium dodecyl sulfate—polyacrylamide gel electrophoresis immunoblots with six different sera identified nine IgE binding bands (16 to 100 kd). Thin-layer isoelectric focusing immunoblots identified 16 IgE binding bands (isoelectric point, 4.5 to 9.3). An aliquot of the Ao extract was diluted in bicarbonate buffer (pH 9.2) and adsorbed to plastic microtiter plates. RAST to Ao and Dp were performed with sera of 163 atopic individuals (88 with allergic rhinitis and 75 with allergic asthma with or without allergic rhinitis). All individuals had appropriately positive skin tests that correlated with a history of exacerbation secondary to allergen exposure. RAST results to Dp and Ao were analyzed by regression analysis ( r = 0.64; p = 0.0001). Fifty-five individuals were RAST positive to Dp alone, 32 to Ao and Dp, and three to Ao alone; 73 individuals were negative to Ao and Dp. RAST inhibition demonstrated moderate cross-reactivity between Ao and Dp.