OBJECTIVETo evaluate the significance of several Dermatophagoides pteronyssinus allergen extracts for skin prick test (SPT) in patients allergic to Dermatophagoides pteronyssinus.

METHODSTwo hundred and nineteen patients enrolled in Peking Union Medical College Hospital underwent SPT and serum specific IgE assay to detect the Dermatophagoides pteronyssinus allergen. Three kinds of house dust mite allergen extracts were used for SPT, including the Dermatophagoides pteronyssinus extract prepared by our laboratory (group A), standardized Dermatophagoides pteronyssinus extract (group B), and mixed extracts of Dermatophagoides pteronyssinus and Dermatophagoides farinae (group C). Human serum specific IgE result was regarded as the reference standard for diagnosis of Dermatophagoides pteronyssinus allergy. The receiver operating characteristic (ROC) curve was used to evaluate the diagnostic performance of SPT with the extracts of three groups.

RESULTSSPT results showed that the median wheal diameter of group A, group B, and group C was 0.43, 0.35, and 0.28 cm, respectively, with significant difference among three groups (P<0.05). The difference was significant between group A and B (P<0.01) as well as group A and C (P<0.01), but not between group B and C (P>0.05). There was no local urticaria or systemic allergic reactions following the procedure of SPT. Local reaction was observed in 5 patients and delayed reaction was in 2 patients of group A. As for group B and C, local reaction occurred in 3 cases and delayed reaction in 2 cases in each group. The area under ROC curve of SPT with extract in group A, group B, and group C was 0.765, 0.801, and 0.782, respectively. Based on the detection results of serum specific IgE, the sensitivity of SPT in diagnosis of Dermatophagoides pteronyssinus allergy with extract of group A, group B, and group C was 92.4%, 87.0%, and 81.5%, and the specificity was 60.6%, 73.2%, and 74.8%, respectively.

CONCLUSIONThe Dermatophagoides pteronyssinus extract for SPT prepared by our laboratory offers good sensitivity and specificity comparable to commercially available allergen extracts, and it may be an appropriate candidate for clinical screening and diagnosis of Dermatophagoides pteronyssinus allergy.

Animals ; Antigens, Dermatophagoides ; immunology ; Dermatophagoides pteronyssinus ; immunology ; Female ; Humans ; Male ; ROC Curve ; Sensitivity and Specificity ; Skin Tests ; methods

Pillows are known to contain significant levels of indoor allergens and endotoxin, that are of importance to house dust mite sensitized asthmatics. Buckwheat pillows are commonly used in Korea. We studied the levels of the house dust mite allergen, Der f 1, and endotoxin on new synthetic and buckwheat pillows and their accumulation over three months. Endotoxin levels were significantly higher on new buckwheat pillows compared to synthetic pillows; geometric mean levels (95% CI) were 60,950 EU/g (30,270-122,700) and 4,887 EU/g (2,570-9,311) respectively (p<0.001). No Der f 1 was detected on the new pillows. After three months Der f 1 levels were similar on buckwheat and synthetic pillows, geometric mean levels (95% CI) were 1.16 microgram/g (0.02-8.13) and 1.08 microgram/g (0.19-1.68) respectively. These results indicate that buckwheat pillows are a source of very high endotoxin levels that may be of relevance to asthma severity of atopic asthmatics.
Allergens/*immunology ; Animals ; Antigens, Dermatophagoides/*immunology ; Asthma/immunology ; *Bedding and Linens ; *Buckwheat ; Dermatophagoides farinae/immunology ; Endotoxins/*immunology ; Humans ; Korea ; Research Support, Non-U.S. Gov't

Animals ; Antigens, Dermatophagoides ; genetics ; immunology ; Arthropod Proteins ; Asthma ; etiology ; therapy ; Humans ; Mice ; Vaccination ; Vaccines, DNA ; immunology

OBJECTIVETo identify the IgE-binding epitopes in the allergen Der p 1 of main house dust mites, which can be recognized by the specific IgE in the sera from allergic individuals, and obtain a hypoallergen derived from the T-B epitope fused peptide for potential use in specific immunotherapy (SIT).

METHODSThirty-one peptides containing 15 amino acids each, which covered the full 222 amino acids of Der p 1 protein sequence, were synthesized on the cellulous membrane by solid-phase peptide (SPOTs) synthesis, with 8 overlapping amino acids between every two neighboring peptides. The membrane bearing the spots of the synthesized peptides were incubated with the allergic serum pools consisting of the sera from 5 allergic individuals. The membrane was then probed with HRP-conjugated anti-human IgE, followed by enhanced chemiluminescence (ECL) for visualization and gray scale analysis of the positive peptide spots.

RESULTSThree strong IgE-binding epitopes were identified in the amino acid sequence of Der p 1 molecule, namely Ep1 (amino acids 85-99), Ep2 (amino acids 106-120) and Ep3 (amino acids 190-204).

CONCLUSIONThe 3 IgE-binding epitopes (B cell epitopes) identified in Der p 1 confirm the presence of linear epitopes in Der p 1, suggesting the possibility of constructing T/B epitope-fused hypoallergens.

Amino Acid Sequence ; Animals ; Antigens, Dermatophagoides ; immunology ; Arthropod Proteins ; immunology ; Binding Sites, Antibody ; Cysteine Endopeptidases ; immunology ; Epitopes ; immunology ; Immunoglobulin E ; immunology ; Lymphokines ; immunology ; Mites ; immunology ; Molecular Sequence Data

Many allergists are currently focusing on the development of new diagnostic tools, and are attempting to improve both the sensitivity and specificity. A multiple allergen simultaneous test-chemiluminescent assay (MAST-CLA) is one of the most popular diagnostic tools used in the Republic of Korea. However, there remains controversy among allergists with regard to the cut-off point for a positive result. The present study was conducted in order to determine the validity of MAST-CLA as compared with that of the skin prick test, with particular emphasis on arthropod allergens, on the basis of percentage agreement rates and k-values, and also to suggest the optimal positive cutoff points using receiver operating characteristic (ROC) curves. The study was conducted with 97 subjects (54 men, 43 women). Optimal individual cut-off points were calculated as follows; class II for Dermatophagoides farinae, class I for Dermatophagoides pteronyssinus, and trace for a cockroach mix. These findings suggest that attempting to apply optimal individual cut-off points will be a good way of improving diagnostic tests, particularly MAST-CLA.
Adult ; Allergens/*immunology ; Animals ; Antigens, Dermatophagoides/*immunology ; Chemiluminescent Measurements/*methods/standards ; Cockroaches/chemistry ; Dermatophagoides farinae/chemistry ; Dermatophagoides pteronyssinus/chemistry ; Female ; Humans ; Hypersensitivity/*diagnosis/immunology ; Insect Proteins/*immunology ; Male ; *ROC Curve ; Skin Tests/methods

OBJECTIVETo construct a vector encoding T-cell epitopes of major allergen group 1 of Dermatophagoides pteronyssinus as a vaccine delivered by MHC class II pathway.

METHODSThe nucleotide sequences of the 3 target genes were synthesized, including TAT, IhC and the recombinant fragment of Der p 1 encoding 3 T-cell epitopes. After amplification of the 3 target fragments by PCR and digestion with corresponding restriction endonucleases, the recombinant gene TAT-IhC-Der p 1-3T was ligated using T4 DNA ligase and inserted into the prokaryotic expression vector pET28a(+) to construct the recombinant plasmid pET-28a(+)-TAT-IhC-Der p 1-3T, which was confirmed by digestion with restriction endonucleases and sequencing. The recombinant vector was transformed into E. coli strain BL21 (DE3) and induced with IPTG, and the induced protein TAT-IhC-Der p 1-3T was detected by SDS-PAGE. After purification, the recombinant protein was confirmed by Western blotting and its allergenicity tested using IgE-binding assay.

RESULTSThe recombinant plasmid pET-28a-TAT-IhC-Der p 1-3T was successfully constructed as confirmed by restriction endonuclease digestion and sequencing and the expression of the recombinant protein TAT-IhC-Der p 1-3T was induced in E. coli. Western blotting verified successfull purification of the target protein, which showed a stronger IgE-binding ability than Der p 1.

CONCLUSIONWe successfully constructed a recombinant expression vector pET-28a-TAT-IhC-Der p 1-3T expressing a T-cell epitope vaccine delivered by MHC II pathway with strong IgE-binding ability, which provides a basis for further study on specific immunotherapy via MHC class II pathway.

Allergens ; immunology ; Animals ; Antigens, Dermatophagoides ; immunology ; Arthropod Proteins ; immunology ; Base Sequence ; Cloning, Molecular ; Cysteine Endopeptidases ; immunology ; Dermatophagoides pteronyssinus ; Epitopes, T-Lymphocyte ; Escherichia coli ; Gene Expression ; Genes, MHC Class II ; Genetic Vectors ; Plasmids ; Polymerase Chain Reaction ; Recombinant Proteins ; immunology ; Vaccines ; immunology

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

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

OBJECTIVE: To evaluate the efficacy and safety of the sublingual immunotherapy with dermatophagoides farinae drops on patients with allergic rhinitis. METHOD: One hundred and twelve cases were collected from adult patients with dust-mite allergic rhinitis of our hospital who could adhere to treatment and regular follow-up. These patients were randomly allocated to receive either sublingual immunotherapy (SLIT group, n = 56) or medical treatment (Control group, n = 56). To evaluate the clinical efficacy by side effects which were registered, symptom and medication scores which were assessed and rhinoconjunctivitis quality of life questionnaire (RQLQ) which was completed in the baseline and two years after treatment. RESULT: Dropouts after the 2 years' treatment were 5 of SLIT group and 4 of Control group respectively. SLIT group induced the significant reductions on both the symptom scores (7.81 ± 3.14 to 3.89 ± 2.01, P < 0.0 1) and the medication scores (2.86 ± 0.75 to 0.44 ± 0.06, P < 0.01). Meanwhile, Control group induced the reductions on both the symptom scores (8.01 ± 3.32 to 5.20 ± 2.43) and the medication scores (2.95 ± 0.80 to 1.75 ± 0.40). There were significant differences (P< 0. 01) in symptom and medication scores between the two groups after 2-year treatment. The patients in SLIT group had fewer symptoms and lower intake of medication. There were statistically significant differences in RQLQ between SLIT group [19 (15,22)] and Control group [36 (26,47)] after two years treatment (Z = -5. 21, P < 0.01). SLIT group also had significant improvement in RQLQ (Z = -6.10, P < 0.01) between before and after the treatment. There were 4 patients who showed adverse reactions in SLIT group (3 occurred in increment period, and 1 occurred in the maintenance period). The incidence of adverse reactions was 7.14%. No severe systemic side effects were registered. CONCLUSION SLIT with standardized dermatophagoides farinae drops in China is safe and effective to patients with allergic rhinitis.
Administration, Sublingual ; Adult ; Animals ; Antigens, Dermatophagoides ; immunology ; China ; Dermatophagoides farinae ; Humans ; Quality of Life ; Rhinitis, Allergic ; drug therapy ; Sublingual Immunotherapy ; Treatment Outcome

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