OBJECTIVEThe prevalence of allergic asthma has been rising continually which is correlated with the increasingly closed living environment. House dust mites are the major sources of indoor aeroallergens which induce asthma in sensitized people. To monitor the seasonal variation of house dust mite (HDM)-allergens exposure level in the asthmatic children, which was evaluated to show its correlation with the level of asthma control, HDM allergic sensitization and fraction of exhaled nitric oxide, and to provide basic data for HDM environmental control.

METHODA total of 48 HDM-allergic asthmatic children were enrolled from the asthma clinic in the hospital from March 2011 to January 2012 (boys 34 and girls 14, aging from 3 to 14 years, mean age 8 years and 4 months) in the present study. Dust samples from mattresses, pillows, bedroom floor, living room floor and sofas were collected in each season within one year in the household of all the enrolled patients. The concentrations of Der p 1 and Der f 1 were measured by the enzyme-linked immunosorbent assay (ELISA). To record the Asthma Control Test (ACT) score or Children Asthma Control Test (C-ACT) score for each patient and to collect the data of doctor monitoring asthma control level each time when the patient was clinic visited. The concentration and its classification of the serum specific IgE to HDM was determined by fluoroenzyme-immunometric assay.

RESULTThe average concentration of Der f 1 of all dust samples was significantly higher than that of Der p 1 (0.13 µg/g vs 0.02 µg/g, P < 0.05). The concentrations of Der f 1 from mattresses, pillows and sofas dust samples were significantly higher than those from bedroom floor and living room floor dust samples (0.69 µg/g, 0.42 µg/g and 0.22 µg/g vs 0.07 µg/g and 0.07 µg/g, P < 0.05). The Der f 1 exposure level from mattress dusts in summer but no others was negatively correlated with asthma control level (r = -0.318, P = 0.036). The Der f 1 exposure level from any area dusts in summer and the Der p 1 exposure level from pillows dusts in autumn was negatively correlated with ACT/C-ACT score respectively. The Der f 1 from mattress dusts in winter was positively correlated with classification of sIgE to Der f 1. The Der p 1 exposure level from most areas in each season was positively correlated with classification of sIgE to Der f 1 and Der P 1.

CONCLUSIONDer f 1 was the predominant mite allergen in household dust and mainly came from mattresses, pillows and sofas. The role of the HDM allergen exposure level on the asthma control level and HDM allergic sensitization for the asthmatic children were depended on its area, season and HDM species, which suggested that the future assessment of clinical effect by the HDM environmental control should consider these factors.

Adolescent ; Air Pollution, Indoor ; adverse effects ; Animals ; Antigens, Dermatophagoides ; analysis ; Asthma ; diagnosis ; etiology ; immunology ; Child ; Child, Preschool ; Dust ; Environmental Exposure ; Enzyme-Linked Immunosorbent Assay ; Female ; Forced Expiratory Volume ; Humans ; Immunoglobulin E ; blood ; Male ; Pyroglyphidae ; immunology ; Risk Factors ; Seasons

We attempted to investigate the correlation between the severity of atopic dermatitis (AD) in children and the indoor level of house dust mite (HDM) allergens. Ninety-five patients (31.1 +/- 19.5 months of age) with AD were enrolled in this study, and serum specific IgE against Dermatophagoides pteronyssinus and D. farinae was measured. The severity of AD was assessed using the visual analogue scale on the same day of house dust collection. Living rooms and mattresses where the child usually slept were vacuumed for 2 minutes and concentrations of Der f 1 were measured by enzyme-linked immunosorbent assay. The skin symptoms were more severe in patients with Der f 1 concentrations in living room > 2 microg/g dust than < or = 2 microg/g dust (P = 0.018). This difference was noted in AD patients without sensitization to HDM (P = 0.004), but not in patients with sensitization. There was no difference in symptom severity according to Der f 1 concentrations in mattresses (P = 0.062). The severity of skin symptoms is associated with indoor concentrations of HDM in children with AD, and it is likely to act as nonspecific irritants as well as allergens in AD skin lesions.
Adolescent ; Animals ; Antigens, Dermatophagoides/*analysis ; Beds/parasitology ; Child ; Child, Preschool ; Dermatitis, Atopic/*diagnosis/pathology ; Dermatophagoides farinae/immunology ; Dermatophagoides pteronyssinus/immunology ; *Enzyme-Linked Immunosorbent Assay ; Female ; Humans ; Immunoglobulin E/blood ; Infant ; Male ; Severity of Illness Index

BACKGROUNDHaikou locates in tropical island with unique mite propagation. The aim of this stuy is to determine mite allergens levels in Haikou, and to investigate the prevalence of mite specific IgE-sensitization and IgE cross-reactivity between house dust mites.

METHODSAllergen and antigen concentrations against six mite species were tested by enzyme-linked immunosorbent assay (ELISA). Specific IgE concentrations and cross-inhibitions were measured with ADVIA Centaur(®).

RESULTSAllergen or antigen Dermatophagoides pteronyssinus (Der p 1), Blomia tropicalis (Blo t) and Tyrophagus putrescentia (Tyr p) were detected in dust samples. Dermatophagoides farinae (Der f 1), Lepidoglyphus destructor (Lep d 2), and Acarus siro (Aca s) were found in very few samples. Specific IgE tests showed high prevalence of sensitizations against all tested mites with high IgE levels to Der p, Der f, and Blo t. Storage mites, Blo t, Tyr p, Lep d, and Aca s, could inhibit Der p from 0 to 50%. Storage mites could inhibit Der f between 30% and 100%. Der p IgE could be inhibited by Der f with up to 90%, and vice versa. Der p could inhibit Blo t from 40% to 80%. Blo t was able to fully inhibit IgE binding to Lep d, Tyr p, and Aca s compared to partial inhibition by Der p.

CONCLUSIONSDer p is the dominating mite and has the highest specific IgE prevalence among asthmatic children. Blo t represents an important source of storage mite sensitization and some patients may be independently sensitized to both Der p and Blo t. High prevalence of sensitization to Der f may be due to IgE-mediated cross-reactivity with Der p and Blo t.

Adolescent ; Air Pollution, Indoor ; Allergens ; analysis ; Animals ; Antigens, Dermatophagoides ; analysis ; Arthropod Proteins ; analysis ; Asthma ; immunology ; Child ; Child, Preschool ; China ; Cross Reactions ; Cysteine Endopeptidases ; analysis ; Dust ; Humans ; Immunoglobulin E ; blood ; immunology ; Mites ; immunology

OBJECTIVE: To investigate the inhaled allergens spectrum of 890 allergic rhinitis patients in Shanghai, and to provide basic epidemiologic information for the prevention and treatment of allergic rhinitis. METHOD: Thirteen allergens skin prick test results of 890 allergic rhinitis patients recruited were retrospectively analyzed. RESULT: The main common inhaled allergens in allergic rhinitis patients in Shanghai were house dust mite (91.24%), dermatophagoides farinae (86.58%), tropical mite (51.98%), dog hair (15.96%). Moreover, the positive frequency was decreased with age increasing, and gender group had no obvious difference. CONCLUSION House dust mite and dermatophagoides farinae were the main allergens of allergic rhinitis patients in Shanghai. Skin prick test is helpful for the discovery of the allergens so as to provide important basis of immunotherapy.
Adolescent ; Adult ; Aged ; Allergens ; analysis ; classification ; immunology ; Animals ; Antigens, Dermatophagoides ; immunology ; Child ; Child, Preschool ; China ; epidemiology ; Female ; Humans ; Male ; Middle Aged ; Mites ; classification ; immunology ; Pyroglyphidae ; immunology ; Rhinitis, Allergic, Perennial ; epidemiology ; Skin Tests ; Young Adult

OBJECTIVE: To study the pathogenesis of the patients with allergic rhinitis diagnosed by Skin Prick Test (SPT), especially about the epidemiologic data of the involved allergens. METHOD: The data was collected from 958 patients referred to the listed three allergy center and subsequently diagnosed as allergic rhinitis by SPT. RESULT: The intermittent mild type was more prevalent in male patients (40.5%); comparably the intermittent moderate type in female patients (70.0%); in the infant patients the moderate-severe type dominated (73.7%). The positive results of SPT comprised mainly of Dermatophagoides pteronyssinus (Der. p, 98.3%), Dermatophagoides farinae(Der. f, 96.8%), and Blomia tropicalis (Blot, 73.8%). Only 1.7% of the patients was allergic to single allergen, in contrary ,the majority of patients were allergic to multiple allergens. The positive rate to Der. p and Der. f was reversely increasing with age of the patients; and contrarily the number of positive allergens was increasing along with the age of the patients. The allergy to outdoor allergen was less common, and the positive rate in skin prick test was lower than the previously reported rate in North China ,such as timothy (3.9%), birch (2.7%), ragweed (2.0%), and mugwort (1.2%). CONCLUSION Dust Mite is the predominant allergen for patients with allergic rhinitis in Guangdong province; and the positive rate to outdoor allergen is lower than that in North China.
Adolescent ; Adult ; Allergens ; analysis ; immunology ; Animals ; Antigens, Dermatophagoides ; analysis ; immunology ; Child ; Child, Preschool ; China ; epidemiology ; Cohort Studies ; Dermatophagoides pteronyssinus ; immunology ; Female ; Humans ; Male ; Middle Aged ; Mites ; immunology ; Rhinitis, Allergic, Perennial ; diagnosis ; epidemiology ; Rhinitis, Allergic, Seasonal ; diagnosis ; epidemiology ; Skin Tests ; Young Adult

PURPOSE: The effects of air cleaners on the removal of airborne indoor allergens, especially house dust mites (HDM), are still controversial. The objective of this study is to evaluate the effect of an air cleaner with an electrostatic filter on the removal of airborne mite allergens. MATERIALS AND METHODS: A dried HDM culture medium that contained mite body particles and excretions was dispersed in a chamber equipped with an electrostatic air cleaner. The number of airborne particles was recorded continuously by a dust spectrometer for 60 minutes. Airborne particles in the chamber were collected on a sampling filter at a flow rate of 10 L/min and the Der f 1 concentration in the filter extracts was measured by two-site ELISA. RESULTS: The air cleaner efficiently removed airborne HDM particles. The air cleaner removed airborne HDM particles (size 2-12.5 microm) 11.4 +/- 2.9 fold (cleaner operating for 15 minutes), 5.4 +/- 0.7 fold (cleaner operating for 30 minutes), and 2.4 +/- 0.2 fold (cleaner operating for 60 minutes) more than the removal of HDM particles by natural settle down. Removal kinetics differed according to the particle size of the airborne particles. The air cleaner decreased the concentration of Der f 1 in the extraction of airborne particles collected on the air sampling filter by 60.3%. CONCLUSION: The electrostatic air cleaner can remove airborne HDM allergens and may be useful as a supplementary environmental control tool for HDM sensitized respiratory allergic patients.
Air Pollution, Indoor/*analysis ; Allergens/analysis ; Animals ; Antigens, Dermatophagoides/*analysis/*immunology ; Culture Media/metabolism ; Dust/analysis/immunology ; Environment ; Environmental Monitoring/methods ; Enzyme-Linked Immunosorbent Assay/methods ; Filtration ; Humans ; Kinetics ; Mites ; Particle Size ; Static Electricity

House dust mites produce inhalant allergens of importance to allergic patients. We measured the major group 1 allergens, Der p 1 and Der f 1, from the house dust mites Dermatophagoides pteronyssinus and Dermatophagoides farina, respectively in 100 randomly selected domestic homes from Cheonan, Korea. Dust samples were collected by vacuuming from the living room floor and 1 mattress in each home. Der p 1 and Der f 1 were measured by double monoclonal ELISA. Der p 1 levels were very low, with geometric mean levels for floors and mattresses being 0.11 microgram/g (range: 0.01-4.05) and 0.14 microgram/g (range: 0.01-30.0), respectively. Corresponding levels of Der f 1 were higher, 7.46 microgram/g (range: 0.01-262.9) and 10.2 microgram/g (range: 0.01-230.9) for floors and mattresses, respectively. D. farinae appears to be the dominant house dust mite in Cheonan.
Animals ; Antigens, Dermatophagoides/immunology/*isolation & purification ; Bedding and Linens ; Dust/analysis ; Floors and Floorcoverings ; Housing ; Humans ; Korea ; Pyroglyphidae/*immunology

OBJECTIVE: To analyze the results of serum in allergic rhinitis and investigate the specific clinic allergen and serum immunoglobulin E (IgE) levels. METHOD: Allergy Screen method was used to detect the specific allergen and total serum IgE level of 134 cases of Allergic rhinitis. RESULT: The dust mite was the most common allergen in inhalation group in 134 cases of allergic rhinitis, the positive rates was 90%; then were donly, feline and scurfy fungus, the positive rates were 16%, 9%. The positive rates of total IgE was 54%. The serum IgE levels between 100 to 200 kU/L, there was 21 cases together, but there existed 7 negative cases. There were 51 cases' IgE levels more than 200 kU/L, the rates was 70.8%, but there still existed 4 negative cases. CONCLUSION Allergy screen method can find relevant allergen and provide basis for the prevention and treatment of allergic disease.
Adult ; Allergens ; blood ; immunology ; Animals ; Antigens, Dermatophagoides ; analysis ; Female ; Humans ; Immunoglobulin E ; blood ; Male ; Mites ; immunology ; Passive Cutaneous Anaphylaxis ; Pollen ; immunology ; Rhinitis, Allergic, Perennial ; diagnosis ; immunology

BACKGROUNDActivation of signal transducer and activator of transcription 6 (STAT6) plays a critical role in the late phase of Th2-dependent allergy induction. STAT6 is essential to Th2 cell differentiation, recruitment, and effector function. Our previous study confirmed that DNA vaccination inhibited STAT6 expression of spleen cells induced by allergen. In the present study, we determined whether DNA vaccine encoding Dermatophagoides pteronyssinus group 2 (Der p2) could down-regulate the expression and activation of STAT6 in lung tissue from asthmatic mice.

METHODSAfter DNA vaccine immunization, BALB/c mice were sensitized by intraperitoneal injection and challenged by intranasal instillation of rDer p2. The levels of the cytokines IL-4 and IL-13 in BAL fluid were measured by enzyme-linked immunosorbent assay. The lung tissue was assessed by immunohistochemical staining with anti-STAT6. The protein expression of STAT6 was determined by Western blot. The activation of STAT6 binding ability was analyzed with electrophoretic mobility shift assay.

RESULTSDNA vaccine encoding Der p2 allergen effectively decreased the levels of IL-4 and IL-13 in the asthmatic mice. Histological evidence and Western blot showed that the expression of STAT6 in the DNA treated mice was markedly attenuated. STAT6 binding to specific DNA motif in lung tissue from the gene vaccinated mice was inhibited.

CONCLUSIONDNA vaccine encoding Der p2 prevents allergic pulmonary inflammation probably by inhibiting the STAT6 signaling pathway in mice with Der p2 allergen-induced allergic airway inflammation.

Animals ; Antigens, Dermatophagoides ; genetics ; immunology ; Arthropod Proteins ; Asthma ; prevention & control ; Down-Regulation ; Electrophoretic Mobility Shift Assay ; Interleukin-13 ; antagonists & inhibitors ; Interleukin-4 ; antagonists & inhibitors ; Lung ; pathology ; Mice ; Mice, Inbred BALB C ; STAT6 Transcription Factor ; analysis ; antagonists & inhibitors ; genetics ; Signal Transduction ; Vaccination ; Vaccines, DNA ; therapeutic use

BACKGROUNDDNA immunization is a promising novel type of immunotherapy against allergy. An estimated 79.2% patients with asthma, wheezing and/or rhinitis suffer from Dermatophagoides pteronyssinus group 2 (Der p 2) allegen. The aim of the present study was to determine whether DNA vaccine encoding Der p 2 could generate immunologic protection in recombinant Der p 2 (rDer p 2) allergen-induced allergic airway inflammation mice model and to understand the role of DNA vaccination in specific-allergen immunotherapy for asthma.

METHODSAfter DNA vaccination, BALB/c mice were sensitized by intraperitoneal injection (i.p) and challenged by intranasal instillation of rDer p 2. The lung tissues were assessed using hematoxylin and eosin. Mucus-producing goblet cells were identifed using periodic acid-Schiff (PAS)/alcian blue. The total cell number and composition of bronchoalveolar lavage samples were determined. The levels of the cytokines IL-4 and IFN-gamma, as well as IgE and IgG2a in the serum were determined by enzyme-linked immunosorbent assay. Allergen-specific IL-4 and IFN-gamma production by spleen cells were also measured by enzyme-linked immunosorbent assay. Expression of signal transducer and activator of transcription 6 (STAT6) in splenocytes were determined by Western blot.

RESULTSDNA vaccine encoding Der p 2 allergen inhibited extensive infiltration of inflammatory cells and production of mucin induced by allergen. The influx of eosinophils into the lung interstitium was significantly reduced after administration of DNA vaccine. Significant reductions of IL-4 and increase in levels of IFN-gamma in bronchoalveolar lavage fluid were observed. The allergen-specific IgE was markedly decreased in mice receiving DNA vaccination. Allergen could induce higher IFN-gamma, weaker IL-4 in cultured spleen cells from mice receiving DNA vaccine. DNA vaccination inhibited STAT6 expression of spleen cells induced by allergen.

CONCLUSIONThese results indicated that DNA vaccine encoding Der p 2 allergen generates immunologic protection in recombinant Der p 2 allergen-induced allergic airway inflammation mice model with regulating the immune response towards a Th1-type reaction.

Animals ; Antigens, Dermatophagoides ; genetics ; immunology ; Arthropod Proteins ; Asthma ; immunology ; therapy ; Eosinophilia ; prevention & control ; Humans ; Immunoglobulin E ; blood ; Immunoglobulin G ; blood ; Interferon-gamma ; biosynthesis ; Interleukin-4 ; biosynthesis ; Mice ; Mice, Inbred BALB C ; STAT6 Transcription Factor ; Th1 Cells ; immunology ; Trans-Activators ; analysis ; Vaccination ; Vaccines, DNA ; immunology