Evaluation of multiple allergen simultaneous (sIgE) testing compared to intradermal testing in the etiological diagnosis of atopic dermatitis in horses

Although intradermal testing (IDT) is commonly used in the etiological diagnosis of allergies, in vitro testing for specific IgE (sIgE) is an attractive alternative. Currently, new laboratory techniques in veterinary allergological practice, including multiple allergen simultaneous tests (MASTs), gradually supersede in vivo tests. Both, serological (sIgE) and IDTs in fourteen atopic Malopolski horses were performed. Correlation and agreement between test results were evaluated. Receiver operating characteristic analysis showed that sIgE to Acarus siro had the best diagnostic performance (Area under the ROC curve [AUC] = 0.969), followed by Dermatophagoides pteronyssinus (AUC = 0.844), Dermatophagoides farinae (AUC = 0.813) and Tyrophagus putrescentiae (AUC = 0.803). A significant positive correlation between IDT and MAST was found for A. siro (r(S) = 0.870; p = 0.00005), and D. farinae (r(S) = 0.657; p = 0.011). There was significant moderate agreement for 2 of 5 allergens, A. siro (κ = 0.569) and D. farinae (κ = 0.485) in semiquantitative assessment and significant fair to substantial agreement for 3 of 5 allergens, D. pteronyssinus (κ = 0.689), A. siro (κ = 0.569), D. farinae (κ = 0.432) in dichotomic assessment. Sensitivity ranged from 44% to 89%, depending on the allergen, while specificity was significantly higher for all allergens in MAST (60%–100%); the mean accuracy was 73% (manufacturer cut-off) and 77.4% (optimal cut-off) based on the Youden index. Compared with IDT, serological MAST showed good detection performance for 60% allergen sIgE in dichotomic assessment with substantial diagnostic capability, but careful clinical interpretation is needed for some allergens.

Allergen Microarrays for In Vitro Diagnostics of Allergies: Comparison with ImmunoCAP and AdvanSure

BACKGROUND: In vitro detection of the allergen-specific IgE antibody (sIgE) is a useful tool for the diagnosis and treatment of allergies. Although multiple simultaneous allergen tests offer simple and low-cost screening methods, these platforms also have limitations with respect to multiplexibility and analytical performance. As an alternative assay platform, we developed and validated a microarray using allergen extracts that we termed “GOLD” chip. METHODS: Serum samples of 150 allergic rhinitis patients were used in the study, and the diagnostic performance of the microarray was compared with that of AdvanSure (LG Life Sciences, Daejun, Korea) and ImmunoCAP (Phadia, Uppsala, Sweden). Standard IgE samples were used for the quantitative measurement of sIgEs. RESULTS: The microarray-based assay showed excellent performance in the quantitative measurement of sIgEs, demonstrating a linear correlation within the range of sIgE concentrations tested. The limit of detection (LOD) was lower than 0.35 IU/mL, which is the current standard for the LOD cut-off. The assay also provided highly reproducible sets of data. The total agreement percentage of positive and negative calls was 92.2% compared with ImmunoCAP. Moreover, an outstanding correlation was observed between the microarray and the ImmunoCAP results, with Cohen's kappa and Pearson correlation coefficient values of 0.80 and 0.79, respectively. CONCLUSIONS: The microarray-based in vitro diagnostic platform offers a sensitive, reproducible, and highly quantitative method to detect sIgEs. The results showed strong correlations with that of ImmunoCAP. These results suggest that the new allergen microarray can serve as a useful alternative to current screening platforms, ultimately becoming a first-line screening method.

Analysis of positive rate of sIgE for common allergens in infants with cow's milk protein allergy / 吉林大学学报(医学版)

Objective:To explore the differences in the positive rates of specific-IgE(sIgE)of the common allergens between the cow's milk protein allergy(CMPA)and healthy infants and the distribution characteristics of positive sIgE of common allergens in the CMPA infants,and to provide basis for comprehensive intervention of the CMPA infants.Methods:A total of 156 cases of CMPA and 318 cases of healthy infants were selected as the subjects.The serum sIgE and total IgE levels of common allergens of the infants in two groups were detected by enzyme-linked immunosorbent assay.The differences in the positive rates of serum sIgE of common allergens and total IgE of the infants in two groups were compared.Results:There were no statistical differences in the positive rates of serum sIgE and total IgE for common allergens of the infants between CMPA group and healthy group(P>0.05).The major food allergens with high positive rates of sIgE in CMPA group were cow's milk(44.2%),egg white(10.3%)and cashew nut(5.1%),and the inhale allergens with high positive rates of sIgE were cat hair (21.2%),dog hair(9.6%)and house dust mite(4.5%).While for the healthy infants,the major food allergens with high positive rates of sIgE were cow's milk(45%),egg white(14.2%)and cashew nut(6.0%),and the inhale allergens with high positive rates of sIgE were cat hair(25.8%),dog hair(14.5%)and fungus combinations(4.5%).The analysis in different age groups(<1 year old and 1-2 years old)showed that there were no statistical differences in the positive rates of serum sIgE and total IgE for common allergens of the infants between CMPA group and healthy group(P>0.05).Conclusion:There are no significant differences in the serum sIgE and total IgE positive rates between the CMPA and healthy infants.The detection of serum sIgE and total IgE of common allergens is of little clinical significance for the CMPA infants.

Analysis of positive rate of sIgE for common allergens in infants with cow's milk protein allergy / 吉林大学学报(医学版)

Objective: To explore the differences in the positive rates of specific-IgE (sIgE) of the common allergens between the cow's milk protein allergy (CMPA) and healthy infants and the distribution characteristics of positive sIgE of common allergens in the CMPA infants, and to provide basis for comprehensive intervention of the CMPA infants. Methods: A total of 156 cases of CMPA and 318 cases of healthy infants were selected as the subjects. The serum sIgE and total IgE levels of common allergens of the infants in two groups were detected by enzyme-lmked immunosorbent assay. The differences in the positive rates of serum sIgE of common allergens and total IgE of the infants in two groups were compared. Results: There were no statistical differences in the positive rates of serum sIgE and total IgE for common allergens of the infants between CMPA group and healthy group (P> 0.05). The major food allergens with high positive rates of sIgE in CMPA group were cow's milk 44.2%), egg white (10.3%) and cashew nut (5.1%), and the inhale allergens with high positive rates of sIgE were cat hair 21.2%), dog hair (9.6%) and house dust mite 4.5%). While for the healthy infants, the major food allergens with high positive rates of sIgE were cow's milk 45%), egg white (14.2%) and cashew nut (6.0%), and the inhale allergens with high positive rates of sIgE were cat hair (25.8%), dog hair (14.5%) and fungus combinations 4.5%). The analysis in different age groups (0.05). Conclusion: There are no significant differences in the serum sIgE and total IgE positive rates between the CMPA and healthy infants. The detection of serum sIgE and total IgE of common allergens is of little clinical significance for the CMPA infants.

Hemocyanin is an important high-molecular-weight allergen of Eriocheir sinensis / 中国免疫学杂志

Objective:To prove hemocyanin is an important high-molecular-weight allergen from Eriocheir sinensis.Methods:The proteins were extracted from Eriocheir sinensis tissue with lysate extraction method .The protein components were analyzed by SDS-PAGE,two-dimensional electrophoresis and Western blot.Serum IgE from allergic donors identified a candidate protein,which was char-acterized by MALDI-TOF/TOF.The immune property of the candidate protein was tested using Dot-blot.Results: By SDS-PAGE and two-dimensional electrophoresis analysis,we prove that the native protein components were completely.According to the Western blot result,at least 18 components could react with the positive serum.Among them, two 70-80 kD proteins had the same isoelectric point.So,may be they were the same protein.MALDI-TOF/TOF analysis results showed that the suspected proteins were hemocyanin.A sensitization frequency of 61%was observed in Eriocheir sinensis patients by Dot-blot.Conclusion:Hemocyanin was identified as an important high-molecular-weight allergen from Eriocheir sinensis.

Changes of serum ECP, Tryptase and aeroallergen-specific IgE in asthmatics with natural remission at puberty / 中国免疫学杂志

Objective:To elucidate the phenomenon of natural remission or even natural recovery of asthma at puberty and put forward the laboratory evidences for the prevention and treatment of asthma Methods:The serum ECP, Tryptase and aeroallergen specific IgE antibody in 23 cases of asthmatics with remission at puberty, 15 cases of asthmatics, 29 cases of normal controls were detected respectively, using Pharmacia Unicap100 Type EIA fluorecent instrument Results: The positive rate of specific IgE antibody in asthmatics with remission at puberty was 66 66%, that in group of asthma was 71 42% and that in normal controls was 6 89% The positive rates of specific IgE in the former two groups were almost the same, and were significantly higher than that in normal controls (P

Detection of Periplaneta americana sIgE with Chemiluminescent Immunoassay(CLIA) / 中国寄生虫学与寄生虫病杂志

Crude extract of Periplaneta americana was prepared by liquid nitrogen grinding.After being purified with DEAE Sephadex A-50 ion exchange chromatography,the protein content of the extract was determined and the extract solution was prepared at gradient concentrations.The crude extract and purified allergen at different concentrations were dotted respectively on nitrocellulose(NC) membrane.Patient serum,bio-IgE,sa-HRP,luminal regents were added to the membrane.The chemiluminescence was displayed by exposing to X-film.The result revealed that the minimum protein content of crude Periplaneta americana extract detected by CLIA is 0.87?g/ml,with 90% accordance to skin test positive patients,and 100% accordance to those with negative skin test and ELISA detection.