海南变态反应性疾病患儿对屋尘螨/粉尘螨和仓储螨的特异性IgE

目的探讨海南变态反应性疾病患儿对尘螨和仓储螨的特异性IgE水平。方法对海南变态反应性疾病患儿进行13种常见变应原皮肤点刺和7种螨的体外特异性IgE检测。结果 121例患儿中对屋尘螨和粉尘螨的皮肤点刺阳性率为100%,而对热带无爪螨的阳性率为85.8%。7种螨的体外特异性IgE依次为屋尘螨99.2%、粉尘螨95.0%、热带无爪螨87.6%、家嗜甜螨79.7%、害嗜鳞螨67.8%、腐食酪螨59.5%和粗脚粉螨52.9%。对仓储螨过敏的患儿同时都对屋尘螨和热带无爪螨过敏,并且IgE水平更高。除热带无爪螨外,其他仓储螨的特异性IgE有很好的相关性。结论除屋尘螨和粉尘螨外,热带无爪螨也是海南地区的重要致敏原,其他仓储螨亦有可能引起慢性变态反应性疾病。

屋尘螨脱敏治疗对变应性鼻炎及哮喘患者血清粉尘螨特异性IgG_4抗体的影响

目的探讨屋尘螨特异性免疫治疗对血清屋尘螨和粉尘螨特异性IgG_4水平的影响。方法32例接受安脱达屋尘螨特异性免疫治疗4～14个月的变应性鼻炎和支气管哮喘患者,抽取其治疗前后血清共64份。采用四层双抗夹心酶联免疫吸附法测定患者血清特异性IgG_4抗体。结果脱敏治疗后的患者血清中屋尘螨和粉尘螨特异性IgG_4抗体水平均有显著上升(P<0.0001),且IgG_4抗体的增长水平与治疗时间呈正相关。结论使用屋尘螨脱敏疫苗治疗所产生的IgG_4抗体能同时识别屋尘螨和粉尘螨两种抗原,从而使机体产生对这两种致敏原的免疫保护作用。

Allergen micro-array detection of specific IgE-reactivity in Chinese allergy patients

Background Allergen micro-arrays are powerful tools for screening of serum IgE-reactivity. In this study allergen micro-arrays were used to identify dominating IgE-binding allergens and cross-reactivity patterns among selected Chinese allergy patients. Methods The study was conducted using patient sera from the cities of Guangzhou, Nanjing, Chengdu and Shenyang. In total 100 sera with Dermatophagoides pteronyssinus （Der p） specific IgE-levels higher than 50 kU/L were selected for testing against 103 individual allergens. Results Among 100 selected patients, 95% showed IgE-reactivity towards house-dust mite allergens Dermatophagoides farinae （Der f） 1, Der f 2 and Der p 2 and 94% were IgE positive against Der p 1, and 60% of sera contained IgE reacting against allergen Euroglyphus maynei （Eur m） 2. IgE against cat allergen, Felisdomesticus （Fel d） 1, was seen in 20%. Only 2% showed specific IgE-reactivity to Der p 10, a panallergen belonging to the tropomyosin family. Serum IgE-reactivity towards other allergens was in general low. IgE-reactivity against pollen allergens showed geographic differences. Conclusions This study clearly confirms that group 1 and group 2 are major allergens of house dust mites. These selected house-dust mite allergy patients are close to being mono-sensitized. Der p 10 is not an important allergen for cross-reactivity. Specific IgE-sensitization towards pollen allergens is low in southern China compared to other regions. The prevalence of food and stinging insect allergens known to give rise to IgE-mediated cross-reactivity is 2% or less.

Prevalence of sensitization to weed pollens of Humulus scandens,Artemisia vulgaris,and Ambrosia artemisiifolia in northern China

Objective:Weed pollens are common sources of allergens worldwide.The prevalence of weed pollen sensitization is not yet fully known in China.The purpose of this study was to investigate the prevalence of sensitization to weed allergens from Artemisia,Ambrosia,and Humulus in northern China.Methods:A total of 1144 subjects(aged from 5 to 68 years) visiting our clinic from June to October 2011 underwent intradermal testing using a panel of 25 allergen sources.Subjects with positive skin responses to any pollen were further tested for their serum concentrations of IgE antibodies against Artemisia vulgaris,Ambrosia artemisiifolia,and Humulus scandens,and against the purified allergens,Art v 1 and Amb a 1.Results:Of 1144 subjects,170 had positive intradermal reactions to pollen and 144 donated serum for IgE testing.The prevalence of positive intradermal responses to pollens of Artemisia sieversiana,Artemisia annua,A.artemisiifolia,and H.scandens was 11.0%,10.2%,3.7%,and 6.6%,respectively.Among the intradermal positive subjects,the prevalence of specific IgE antigens to A.vulgaris was 58.3%,to A.artemisiifolia 14.7%,and to H.scandens 41.0%.The prevalence of specific IgE antigens to the allergen Art v 1 was 46.9%,and to Amb a 1 was 11.2%.The correlation between the presence of IgE antibodies specific to A.vulgaris and to the Art v 1 antigen was very high.Subjects with A.artemisiifolia specific IgE also had A.vulgaris specific IgE,but with relatively high levels of A.vulgaris IgE antibodies.There were no correlations between the presence of IgE antibodies to H.scandens and A.vulgaris or to H.scandens and A.artemisiifolia.Conclusions:The intradermal prevalence of weed pollen sensitization among allergic subjects in northern China is about 13.5%.Correlations of specific IgE antibodies suggest that pollen allergens from Artemisia and Humulus are independent sources for primary sensitization.

Prevalence of sensitivity to cockroach allergens and IgE crossreactivity between cockroach and house dust mite allergens in Chinese patients with allergic rhinitis and asthma

Background Cockroaches are an important indoor allergen source causing allergic rhinitis and asthma. The aim of this study was to investigate the cockroach prevalence in mainland of China and the cross-reactivity of IgE between cockroach and house dust mite allergen in Chinese patients.Methods The cockroach sensitization pattern was based on a skin prick test （SPT） obtained from a national multicenter prevalence study, in which 6304 patients from 25 allergy centers across China participated. Factors, including different regions of China, age, gender and the correlations between the American and German cockroaches and house dust mite Der p were investigated. Eighteen out of 1236 clinical sera from south China were selected to perform the cross-inhibition assay between house dust mites and cockroaches.Results Totally 25.7% of patients were SPT positive to the American cockroach （Periplaneta Americana, Per a） and 18.7% SPT positive to the German cockroach （Blattella germanica, Bla g）. The prevalence of positive cockroach SPT was higher in southern than in northern China, higher in adults than in children, and higher in males than in females.Patients had relatively low levels of cockroach SPT reactions, mainly class 1 or 2. Of the SPT positive cockroach patients,88% were also SPT positive to house dust mite （Dermatophagoides pteronyssinus, Der p）. An IgE cross-inhibition study confirmed that Der P sensitization could cause false positive SPT reactions against cockroach.Conclusions A relatively high prevalence of cockroach sensitivity was found in mainland of China. However, a cross-inhibition study showed that only a small number of patients appear to have Bla g and/or Per a as primary sensitizing source. The importance of cockroaches as a risk factor for sensitization and triggers of allergic symptoms in mainland of China needs to be further investigated.

Indoor mite allergen levels, specific IgE prevalence and IgE cross-inhibition pattern among asthmatic children in Haikou, southern China

Background Haikou locates in tropical island with unique mite allergens levels in Haikou, and to investigate the prevalence of between house dust mites. propagation. The aim of this stuy is to determine mite mite specific IgE-sensitization and IgE cross-reactivity Methods Allergen 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 . Results Allergen or antigen Dermatophagoides pteronyssinus （Der p 1 ）, Blomia tropicalis （BIot ） 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 BIot. Storage mites, BIo 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 BIot from 40% to 80%. BIot was able to fully inhibit IgE binding to Lep d, Tyr p, and Aca s compared to partial inhibition by Der p. Conclusions Der p is the dominating mite and has the highest specific IgE prevalence among asthmatic children. BIot represents an important source of storage mite sensitization and some patients may be independently sensitized to both Der p and BIot. High prevalence of sensitization to Der f may be due to IgE-mediated cross-reactivity with Der p and BIo t.