Objective:To examine the acaricidal effects of the essential oil of Cymbopogon citratits leaf extract(lemongrass)and ethanolic Azadirachta indica leaf extract(neem)against house dust mites Dermatophagoides farinae(D.f...Objective:To examine the acaricidal effects of the essential oil of Cymbopogon citratits leaf extract(lemongrass)and ethanolic Azadirachta indica leaf extract(neem)against house dust mites Dermatophagoides farinae(D.farinae)and Dermalophagoides pteronyssinus(D.pteronyssinus).Methods:Twenty-five adults mites were placed onto treated filter paper that is soaked with plant extract and been tested at different concentrations(50.00%,25.00%,12.50%,6.25%and 3.13%)and exposure times(24hrs,48hrs,72hrs and 96 hrs).All treatments were replicated 7 times,and the experiment repeated once.The topical and contact activities of the two herbs were investigated.Results:Mortalities from lemongrass extract were higher than neem for both topical and contact activities.At 50%concentration,both 24 hrs topical and contact exposures to lemongrass resulted in more than 91%mortalities for both species of inites.At the same concentration and exposure time,neem resulted in topical mortalities of 40.3%and 15.7%against D.pteronyssinus and D.farinae respectively;contact mortalities were 8.0%and 8.9%against the 2 mites,respectively.There was no difference in topical mortalities of D.pteronyssinus from exposure to concentrations oflemongrass and neem up to 12.50%;lemongrass was more effective than neem at the higher concentrations.Conclusions:Generally,topical mortalities of D.farinae due to lemongrass are higher than that due to neem.Contact mortalities of lemongrass are always higher that neem against both species of mites.展开更多
Dermatophagoides farinae and D. pteronyssinus are the prevalent house dust mites (HDM) in tropical countries and are associated with allergic diseases. This investigation developed a time- resolved immunofluorometric ...Dermatophagoides farinae and D. pteronyssinus are the prevalent house dust mites (HDM) in tropical countries and are associated with allergic diseases. This investigation developed a time- resolved immunofluorometric assay (TR-IFMA) for the first time to detect specific IgE antibody in patients with skin prick test positive to HDM but no detectable IgE by other means. Levels of IgE to natural and recombinant HDM allergens were measured by TR-IFMA in 50 HDM-allergic patients and 19 healthy participants compared to sandwich enzyme-linked immunosorbent assay (ELISA). A recombinant allergen, rDerf2, showed a 14 kDa band corresponding to broad range proteins of natural HDM.TR-IFMA showed sensitivity lower than 0.35 kUA/l. TR-IFMA employing three HDM antigens showed good correlations with sandwich ELISA at R2 0.93-0.96. TR-IFMA detected HDM IgE in 62, 62, 25 percent of allergic patient serum sample compared to 28, 32, and 22 percent detected by ELISA result using three HDM allergen. TR-IFMA also detected 26.3, 31.6, and 5.3 percent positive samples from 19 healthy participants while ELISA showed 0, 5.3, and 0 percents IgE positive samples. The use of rDerf2 as an HDM allergen for the assay was verified with no statistically different from other HDM allergens. TR-IFMA showed lower detection limit than ELISA and yielded higher sensitivity for serum of people with allergic symptoms with no detectable HDM IgE. It is anticipated that TR-IFMA for HDM-specific IgE detection will play an important role in future diagnosis of HDM allergy in clinical laboratories and for different research purposes.展开更多
To measure Derp1 and Blot5 allergen levels in asthmatics’ homes in Hongkong. Methods Seventy houses were enrolled for a mite indoor environment study. Dust samples were obtained from two sites of each patients’ hous...To measure Derp1 and Blot5 allergen levels in asthmatics’ homes in Hongkong. Methods Seventy houses were enrolled for a mite indoor environment study. Dust samples were obtained from two sites of each patients’ house: bed and floor. Derp1 and Blot5 levels were quantified by a two-site monoclonal antibody-based ELISA technique. Results The levels of Derp1 allergens found in bed (geometric mean (GM) 3.43 μg/g of dust; 95%CI, 1.89-4.96 μg/g) and on the floor (GM 1.12 μg/g of dust; 95%CI, 0.71-1.53 μg/g) indicated significant differences (P = 0.005). However, the levels of Blot5 allergens found in bed (GM 19.00 μg/g of dust; 95%CI, 0.89-38.90 μg/g) and on the floor (GM 6.14 μg/g of dust; 95%CI, 0.40-11.90 μg/g) showed no statistically significant difference. In addition, in regards to the exposure index for Derp1 and Blot5 allergens found in bed and on the floor, 17.6% in bed and 8.6% on the floor had levels of Blot5 ≥ 10 μg/g of dust, higher than those obtained for Derp1 (7.2% and 0% in bed and on the floor respectively, P < 0.05); higher percentages in bed and on the floor (25.0% and 35.7%) were observed for levels of Blot5 = 0 μg/g of dust as compared with Derp1 in bed and on the floor (4.3% and 14.5% respectively, P < 0.05). Conclusions Derp1 and Blot5 are the major allergens found in this regional study, Blot5 is a more potent allergen in Hongkong, probably reflecting the high level of exposure to Blomia tropicalis (Bt). Bt and Dermatophagoides pteronyssinus(Dp) allergens should be included for precise diagnosis and effective immuno-therapeutic treatment of mite allergy in Hong-kong.展开更多
The acaricidal activities of fourteen essential oils and fourteen of their major monoterpenoids were tested against house dust mites Dermatophagoides pteronyssinus. Five concentrations were used over two different tim...The acaricidal activities of fourteen essential oils and fourteen of their major monoterpenoids were tested against house dust mites Dermatophagoides pteronyssinus. Five concentrations were used over two different time intervals 24 and 48 h under laboratory conditions. In general, it was noticed that the acaricidal effect based on LC50 of either essential oils or monoterpenoids against the mite was time dependant. The LCso values were decreased by increasing of exposure time. Clove, matrecary, chenopodium, rosemary, eucalyptus and caraway oils were shown to have high activity. As for the monoterpenoids, cinnamaldehyde and chlorothymol were found to be the most effective followed by citronellol. This study suggests the use of the essential oils and their major constituents as ecofriendly biodegradable agents for the control of house dust mite, D. pteronyssinus.展开更多
Extensive research of respiratory physiology and diseases of the airways and lungs provides better understanding of mechanisms of diseases and it is a source of new data with potential clinical application. The majori...Extensive research of respiratory physiology and diseases of the airways and lungs provides better understanding of mechanisms of diseases and it is a source of new data with potential clinical application. The majority of the data in the field of airway defensive reflexes were obtained from guinea pig model, as the most convenient one. Neurophysiology and neuropharma-cology of the cough reflex—which is exclusively mediated by the vagus nerve, share close similarities between guinea pigs and humans. The models used to study pathological processes and their influence on airway-defensive reflexes use sensitization with ovalbumin—the protein from chicken egg, which does not mimic allergies within human respiratory system. House dust mites (HDM) (Dermatophagoides pteronyssius and Dermatophagoides farinae) represent frequent human aeroallergens, however the HDM models are used considerably less than ovalbumin models. The primary objective of this review is to focus on already validated models of HDM-induced airway diseases to see, whether some of them are suitable to study mechanisms of peripheral cough plasticity in a condition of HDM-induced pathological processes. The main purpose of future use and validation of HDM model is to produce higher ability to translate the results obtained in animal models to human cough research.展开更多
The house dust mites (Dermatophagoides farinae, Derf) are the major source of aeroaller gens implicated in the expression of atopic disorders, including asthma, allergic rhinitis and atopic dermatitis. In particular, ...The house dust mites (Dermatophagoides farinae, Derf) are the major source of aeroaller gens implicated in the expression of atopic disorders, including asthma, allergic rhinitis and atopic dermatitis. In particular, strong circumstantial evidence suggests that house dust mite antigens are important precipitating factors of asthma. Many house dust mite allergens are proteases that can elicit airway inflammation by stimulating the release of cytokines from bronchial epithelial cells. To investigate whether Der f allergen proteases induced cytokine production from the epithelial cell line BEAS-2B, BEAS-2B cells were cultured with 4 different concentrations of Derf (0.02, 0.2, 2, 20μg/ml) for 24-96 h, after which supernatants were assayed for interleukin (IL)-6 and IL-8 with ELISA. Reverse transcription-PCR was also performed. The cell sheets were intact throughout the observation in control group without any exposure to Der f antigen. In the experimental groups cells treated with Der f allergen showed changes in the anchorage status of the monolayer. There was a significant increase in the level of cytokine production compared with the untreated sample. The release of IL-6 and IL-8 increased in a concentration-dependent manner (P <0.05, respectively) with the addition of increasing dosage of Der f to the cell sheets. Levels of IL-6 and IL-8 began to rise at 24 h and 48 h after allergen exposure, and they increased significantly in the supematants at 72 h and 96 h. At the same time the concentration dependence of induction of IL-6 and IL-8 expression as well as an increase in the expression of IL-6 and IL-8 mRNA manifested evidently. HDM-induced airway inflammation may include Der f-mediated release of inflammatory mediators, and the proteolytic activity of an allergen may stimulate the release of proinflammatory cytokines from human bronchial epithelium. It is suggested that IL-6 and IL-8 production by bronchial epithelial cells may play a role in the pathogenesis of allergic asthma.展开更多
Objective Chinese allergic subjects have high levels of sensitization to house dust mite （HDM） and other indoor allergens. This study quantifies common indoor allergen levels in Chinese households. Methods Dust samp...Objective Chinese allergic subjects have high levels of sensitization to house dust mite （HDM） and other indoor allergens. This study quantifies common indoor allergen levels in Chinese households. Methods Dust samples were collected from nine cities. Major allergens Der p 1 and Der f I from Dermatophagoides pteronyssinus and D. farinae, and specific antigens of Blomia tropicalis, Tyrophagus putrescentiae, Acarus siro, and cockroach species Blattella germanica and Periplaneta americana were measured by ELISA.Results HDM allergens were found in dust samples from bedding in 95% of the Chinese households. The median levels varied from 〈0.006 to 9.2 μg/g of dust, depending on the city. The percentages of households having HDM allergen levels associated with the risk of developing allergy sensitization and asthma were 65% and 25%, respectively. Specific antigens of the storage mite and cockroach were only found in samples from the southern and tropical regions of China. Levels of mite allergens were generally higher in samples from bedding compared to samples from the living room, even for storage mites, whereas levels of cockroach antigens were higher in the living room samples.Conclusion HDM allergens are present in bedding dust samples from most Chinese households. Cities in southern and central China have relatively high levels of HDM major allergens compared to cities in northern and western China. Antigens of storage mites and cockroaches are not as common as HDM allergens.展开更多
Air pollutants can potentially lead to nitration of allergic proteins,thus promoting sensitization of these allergens.However,little is currently known about the nitration status of house dust mite(HDM)allergens.We id...Air pollutants can potentially lead to nitration of allergic proteins,thus promoting sensitization of these allergens.However,little is currently known about the nitration status of house dust mite(HDM)allergens.We identified the occurrence of nitrated products of two major HDM allergens Der f 1 and Der p 1 in dust samples collected from college dormitories in eastern China and assessed their associated health risk.The results showed that both non-nitrated and nitrated forms of the two allergens were detected in the dust in the range of non-detected(ND)-10.6,1.44-15.4,ND-22.4,ND-7.28μg/g for non-nitrated Der f 1,nitrated Der f 1,non-nitrated Der p 1 and nitrated Der p 1,respectively.The median rates of nitration were determined as 74.0%for Der f 1 and 20.4% for Der p 1 at consideration of one nitration site.Further analysis reveals that the levels of HDM allergens and their nitrated products were found to be generally higher during winter,in dormitories of lower altitude and with female occupants.Furthermore,the calculated risk indexes were at considerably high levels.Our findings suggest that nitrated HDM allergens have already accumulated in the environment at such significant levels and their associated health risk calls for our immediate attention.展开更多
The interaction of house dust mites(HDM)and microorganisms is the key factor in the survival of these mites in human-made environments.Spent growth medium(SPGM)provides the rest of the dict,along with dead mite bodies...The interaction of house dust mites(HDM)and microorganisms is the key factor in the survival of these mites in human-made environments.Spent growth medium(SPGM)provides the rest of the dict,along with dead mite bodies and microorganisms.SPGM represents a source of microorganisms for the recolonization of mite food and the mite digestive tract.An experiment was performed to observe how adding SPGM to the HDM diet affects HDM population growth,the microbiome composition and the microbial respiration in microcosms.We analyzed American house dust mite(Dermatophagoides farinae)and European house dust mite(Dermatophagoides pleronyssinus)originating from control diets and diets treated with an extract of SPGM from 1-and 3-month-old mite cultures.The microbiome was described using 16S and 18S barcode sequencing.The composition of the bacterial and fiungal microbiomes differed between the HDM species,but the SPGM treatment influenced only the bacterial profile of D.farinae.In the D.farinae microbiome of specimens on SPGM-treated dicts compared to those of the control situation,the Lactobacillus profile decreased,while the Candinium,Staphylococ-cus,Acinetobacter,and Sphingomonas profiles increased.The addition of SPGM extract decreased the microbial respiration in the microcosms with and without mites in almost all cascs.Adding SPGM did not influence the population growth of D.farinae,but it had a variable effect on D.pteronyssimus.The results indicated that the HDM are marginally influenced by the microorganisms in their feces.展开更多
目的:观察舌下免疫治疗(SLIT)疗效与尘螨组分sIgE和sIgG4水平变化的相关性。方法:回顾性分析2018年4月~2021年10月就诊于某院过敏反应科并行SLIT的过敏性鼻炎患儿(n=37),根据治疗1年后症状和药物综合评分(CSMS)分为控制稳定组(n=25)和...目的:观察舌下免疫治疗(SLIT)疗效与尘螨组分sIgE和sIgG4水平变化的相关性。方法:回顾性分析2018年4月~2021年10月就诊于某院过敏反应科并行SLIT的过敏性鼻炎患儿(n=37),根据治疗1年后症状和药物综合评分(CSMS)分为控制稳定组(n=25)和控制不稳定组(n=12),比较两组患儿9种重要尘螨致敏蛋白组分(Derp1/Derf1、Derp2/Derf2、Derp5、Derp7、Derp10、Derp21和Derp23)sIgE和sIgG4的水平变化。结果:Derp1/Derf1和Derp2/Derf2为主要致敏蛋白组分,其治疗前sIgE阳性率为86.5%~94.6%,其中Der p 2的sIgE浓度高于Derp1(P<0.0001)、Derp5(P<0.001)、Derp7(P<0.001)、Derp10(P<0.001)、Derp21(P<0.01);Derf2的sIgE浓度高于Derf1(P<0.0001)、Derp5(P<0.0001)、Derp7(P<0.0001)、Der p 10(P<0.0001)、Der p 21(P<0.0001)和Der p 23(P<0.01)。治疗前Der f 2的sIgG4浓度高于其他组分(P<0.0001),控制不稳定组中Der f 1的sIgG4阳性率(33.3%)高于控制稳定组(4.0%,P<0.05),且控制不稳定组中Derf1和Derp10的sIgG4浓度高于控制稳定组(P<0.05)。治疗1年后,控制稳定组患儿Der f 1和Der p 2的sIgG4水平高于治疗前(P<0.05)。结论:尘螨致敏过敏性鼻炎患儿应用SLIT治疗后,Der f 1和Der p 2的sIgG4浓度升高明显,提示SLIT疗效较好,为临床评估SLIT疗效提供了线索。展开更多
Background Subcutaneous specific immunotherapy has been demonstrated to be capable of inducing T-cell regulatory response.Interleukin-10 （IL-10） plays a crucial role in inducing allergen-specific tolerance.However t...Background Subcutaneous specific immunotherapy has been demonstrated to be capable of inducing T-cell regulatory response.Interleukin-10 （IL-10） plays a crucial role in inducing allergen-specific tolerance.However the reports of the changes of IL-10 in house dust mite （HDM）-specific immunotherapy were varied.The aim of this study was to evaluate the function of IL-10-secreting regulatory T cells in asthma children successfully treated with HDM immunotherapy.Methods Peripheral blood mononuclear cells （PBMCs） were isolated from 27 patients following 1.5--2 years of HDM-specific immunotherapy （SIT, SIT group） and from 27 matched treated asthmatic children allergic to HDM （asthmagroup）.After 48 hours of in vitro stimulation with HDM extracts, IL-10-secreting regulatory T cells were measured by four colour flow cytometry.Sera were tested for allergen-specific IgG4 and IgE using the Immuno CAP 100 assay.Results PBMCs from children undergoing immunotherapy following HDM extracts stimuli produced significantly more IL-10 compared with the asthma group.The frequency of iTreg cells and aTreg cells increased in SIT group after HDM stimulation, while it was not affected in the asthma group.Among the iTreg cells and aTreg cells, the frequency of CD4＋CD25-Foxp3-IL-10＋ Treg cells increased the most which was 2 times higher than that in unstimulated cultures in SIT group.The levels of HDM-specific IgG4 of SIT group was significiently higher compared with asthma group, but there was no correlation of the levels of HDM-specific IgG4 and IL-10 secreting Treg cells.Conclusions HDM-specific immunotherapy can successfully upregulate the frequency of IL-10-secreting Treg cells.CD4＋CD25-Foxp3-IL-10＋ Treg cells may play a key role in inducing the immune tolerance in HDM-specific immunotherapy.展开更多
The cysteine protease caspase-1(Casp-1)contributes to innate immunity through the assembly of NLRP3,NLRC4,AIM2,and NLRP6 inflammasomes.Here we ask whether caspase-1 activation plays a regulatory role in house dust mit...The cysteine protease caspase-1(Casp-1)contributes to innate immunity through the assembly of NLRP3,NLRC4,AIM2,and NLRP6 inflammasomes.Here we ask whether caspase-1 activation plays a regulatory role in house dust mite(HDM)-induced experimental allergic airway inflammation.We report enhanced airway inflammation in caspase-1-deficient mice exposed toHDMwith a marked eosinophil recruitment,increased expression of IL-4,IL-5,IL-13,aswell as full-length and bioactive IL-33.Furthermore,mice deficient for NLRP3 failed to control eosinophil influx in the airways and displayed augmented Th2 cytokine and chemokine levels,suggesting that the NLPR3 inflammasome complex controls HDM-induced inflammation.IL-33 neutralization by administration of soluble ST2 receptor inhibited the enhanced allergic inflammation,while administration of recombinant IL-33 during challenge phase enhanced allergic inflammation in caspase-1-deficient mice.Therefore,we show that caspase-1,NLRP3,and ASC,but not NLRC4,contribute to the upregulation of allergic lung inflammation.Moreover,we cannot exclude an effect of caspase-11,because caspase-1-deficient mice are deficient for both caspases.Mechanistically,absence of caspase-1 is associated with increased expression of IL-33,uric acid,and spleen tyrosine kinase(Syk)production.This study highlights acritical role of caspase-1 activation andNLPR3/ASCinflammasomecomplex in the down-modulation of IL-33 in vivo and in vitro,thereby regulating Th2 response in HDM-induced allergic lung inflammation.展开更多
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 I...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.展开更多
过敏原的硝基化会引起其致敏潜能的增强,进而带来更大的致敏性健康风险.过敏原蛋白质通常含有多个酪氨酸硝基化位点,分析过敏原硝基化的位点选择性是探究硝基化对过敏原致敏性影响的重要基础.本文以尘螨过敏原为研究对象,建立了基于超...过敏原的硝基化会引起其致敏潜能的增强,进而带来更大的致敏性健康风险.过敏原蛋白质通常含有多个酪氨酸硝基化位点,分析过敏原硝基化的位点选择性是探究硝基化对过敏原致敏性影响的重要基础.本文以尘螨过敏原为研究对象,建立了基于超高效液相色谱-串联质谱(UPLC-MS/MS)同时定量分析3种尘螨过敏原(Der f 1、Der p 1和Der p 2)的13个酪氨酸位点硝基化程度的方法,并应用于分析3种尘螨过敏原在过氧亚硝酸盐硝基化作用下的位点选择性.结果表明,3种尘螨过敏原均发生了位点特异性的硝基化,Y195、Y37和Y92分别为Der f 1、Der p 1和Der p 2中反应活性最高的硝基化位点.尘螨过敏原位点选择性的硝基化表明,在评价硝基化尘螨过敏原的致敏性变化时应当考虑其位点特异性的硝基化状况.展开更多
文摘Objective:To examine the acaricidal effects of the essential oil of Cymbopogon citratits leaf extract(lemongrass)and ethanolic Azadirachta indica leaf extract(neem)against house dust mites Dermatophagoides farinae(D.farinae)and Dermalophagoides pteronyssinus(D.pteronyssinus).Methods:Twenty-five adults mites were placed onto treated filter paper that is soaked with plant extract and been tested at different concentrations(50.00%,25.00%,12.50%,6.25%and 3.13%)and exposure times(24hrs,48hrs,72hrs and 96 hrs).All treatments were replicated 7 times,and the experiment repeated once.The topical and contact activities of the two herbs were investigated.Results:Mortalities from lemongrass extract were higher than neem for both topical and contact activities.At 50%concentration,both 24 hrs topical and contact exposures to lemongrass resulted in more than 91%mortalities for both species of inites.At the same concentration and exposure time,neem resulted in topical mortalities of 40.3%and 15.7%against D.pteronyssinus and D.farinae respectively;contact mortalities were 8.0%and 8.9%against the 2 mites,respectively.There was no difference in topical mortalities of D.pteronyssinus from exposure to concentrations oflemongrass and neem up to 12.50%;lemongrass was more effective than neem at the higher concentrations.Conclusions:Generally,topical mortalities of D.farinae due to lemongrass are higher than that due to neem.Contact mortalities of lemongrass are always higher that neem against both species of mites.
文摘Dermatophagoides farinae and D. pteronyssinus are the prevalent house dust mites (HDM) in tropical countries and are associated with allergic diseases. This investigation developed a time- resolved immunofluorometric assay (TR-IFMA) for the first time to detect specific IgE antibody in patients with skin prick test positive to HDM but no detectable IgE by other means. Levels of IgE to natural and recombinant HDM allergens were measured by TR-IFMA in 50 HDM-allergic patients and 19 healthy participants compared to sandwich enzyme-linked immunosorbent assay (ELISA). A recombinant allergen, rDerf2, showed a 14 kDa band corresponding to broad range proteins of natural HDM.TR-IFMA showed sensitivity lower than 0.35 kUA/l. TR-IFMA employing three HDM antigens showed good correlations with sandwich ELISA at R2 0.93-0.96. TR-IFMA detected HDM IgE in 62, 62, 25 percent of allergic patient serum sample compared to 28, 32, and 22 percent detected by ELISA result using three HDM allergen. TR-IFMA also detected 26.3, 31.6, and 5.3 percent positive samples from 19 healthy participants while ELISA showed 0, 5.3, and 0 percents IgE positive samples. The use of rDerf2 as an HDM allergen for the assay was verified with no statistically different from other HDM allergens. TR-IFMA showed lower detection limit than ELISA and yielded higher sensitivity for serum of people with allergic symptoms with no detectable HDM IgE. It is anticipated that TR-IFMA for HDM-specific IgE detection will play an important role in future diagnosis of HDM allergy in clinical laboratories and for different research purposes.
文摘To measure Derp1 and Blot5 allergen levels in asthmatics’ homes in Hongkong. Methods Seventy houses were enrolled for a mite indoor environment study. Dust samples were obtained from two sites of each patients’ house: bed and floor. Derp1 and Blot5 levels were quantified by a two-site monoclonal antibody-based ELISA technique. Results The levels of Derp1 allergens found in bed (geometric mean (GM) 3.43 μg/g of dust; 95%CI, 1.89-4.96 μg/g) and on the floor (GM 1.12 μg/g of dust; 95%CI, 0.71-1.53 μg/g) indicated significant differences (P = 0.005). However, the levels of Blot5 allergens found in bed (GM 19.00 μg/g of dust; 95%CI, 0.89-38.90 μg/g) and on the floor (GM 6.14 μg/g of dust; 95%CI, 0.40-11.90 μg/g) showed no statistically significant difference. In addition, in regards to the exposure index for Derp1 and Blot5 allergens found in bed and on the floor, 17.6% in bed and 8.6% on the floor had levels of Blot5 ≥ 10 μg/g of dust, higher than those obtained for Derp1 (7.2% and 0% in bed and on the floor respectively, P < 0.05); higher percentages in bed and on the floor (25.0% and 35.7%) were observed for levels of Blot5 = 0 μg/g of dust as compared with Derp1 in bed and on the floor (4.3% and 14.5% respectively, P < 0.05). Conclusions Derp1 and Blot5 are the major allergens found in this regional study, Blot5 is a more potent allergen in Hongkong, probably reflecting the high level of exposure to Blomia tropicalis (Bt). Bt and Dermatophagoides pteronyssinus(Dp) allergens should be included for precise diagnosis and effective immuno-therapeutic treatment of mite allergy in Hong-kong.
文摘The acaricidal activities of fourteen essential oils and fourteen of their major monoterpenoids were tested against house dust mites Dermatophagoides pteronyssinus. Five concentrations were used over two different time intervals 24 and 48 h under laboratory conditions. In general, it was noticed that the acaricidal effect based on LC50 of either essential oils or monoterpenoids against the mite was time dependant. The LCso values were decreased by increasing of exposure time. Clove, matrecary, chenopodium, rosemary, eucalyptus and caraway oils were shown to have high activity. As for the monoterpenoids, cinnamaldehyde and chlorothymol were found to be the most effective followed by citronellol. This study suggests the use of the essential oils and their major constituents as ecofriendly biodegradable agents for the control of house dust mite, D. pteronyssinus.
文摘Extensive research of respiratory physiology and diseases of the airways and lungs provides better understanding of mechanisms of diseases and it is a source of new data with potential clinical application. The majority of the data in the field of airway defensive reflexes were obtained from guinea pig model, as the most convenient one. Neurophysiology and neuropharma-cology of the cough reflex—which is exclusively mediated by the vagus nerve, share close similarities between guinea pigs and humans. The models used to study pathological processes and their influence on airway-defensive reflexes use sensitization with ovalbumin—the protein from chicken egg, which does not mimic allergies within human respiratory system. House dust mites (HDM) (Dermatophagoides pteronyssius and Dermatophagoides farinae) represent frequent human aeroallergens, however the HDM models are used considerably less than ovalbumin models. The primary objective of this review is to focus on already validated models of HDM-induced airway diseases to see, whether some of them are suitable to study mechanisms of peripheral cough plasticity in a condition of HDM-induced pathological processes. The main purpose of future use and validation of HDM model is to produce higher ability to translate the results obtained in animal models to human cough research.
文摘The house dust mites (Dermatophagoides farinae, Derf) are the major source of aeroaller gens implicated in the expression of atopic disorders, including asthma, allergic rhinitis and atopic dermatitis. In particular, strong circumstantial evidence suggests that house dust mite antigens are important precipitating factors of asthma. Many house dust mite allergens are proteases that can elicit airway inflammation by stimulating the release of cytokines from bronchial epithelial cells. To investigate whether Der f allergen proteases induced cytokine production from the epithelial cell line BEAS-2B, BEAS-2B cells were cultured with 4 different concentrations of Derf (0.02, 0.2, 2, 20μg/ml) for 24-96 h, after which supernatants were assayed for interleukin (IL)-6 and IL-8 with ELISA. Reverse transcription-PCR was also performed. The cell sheets were intact throughout the observation in control group without any exposure to Der f antigen. In the experimental groups cells treated with Der f allergen showed changes in the anchorage status of the monolayer. There was a significant increase in the level of cytokine production compared with the untreated sample. The release of IL-6 and IL-8 increased in a concentration-dependent manner (P <0.05, respectively) with the addition of increasing dosage of Der f to the cell sheets. Levels of IL-6 and IL-8 began to rise at 24 h and 48 h after allergen exposure, and they increased significantly in the supematants at 72 h and 96 h. At the same time the concentration dependence of induction of IL-6 and IL-8 expression as well as an increase in the expression of IL-6 and IL-8 mRNA manifested evidently. HDM-induced airway inflammation may include Der f-mediated release of inflammatory mediators, and the proteolytic activity of an allergen may stimulate the release of proinflammatory cytokines from human bronchial epithelium. It is suggested that IL-6 and IL-8 production by bronchial epithelial cells may play a role in the pathogenesis of allergic asthma.
文摘Objective Chinese allergic subjects have high levels of sensitization to house dust mite （HDM） and other indoor allergens. This study quantifies common indoor allergen levels in Chinese households. Methods Dust samples were collected from nine cities. Major allergens Der p 1 and Der f I from Dermatophagoides pteronyssinus and D. farinae, and specific antigens of Blomia tropicalis, Tyrophagus putrescentiae, Acarus siro, and cockroach species Blattella germanica and Periplaneta americana were measured by ELISA.Results HDM allergens were found in dust samples from bedding in 95% of the Chinese households. The median levels varied from 〈0.006 to 9.2 μg/g of dust, depending on the city. The percentages of households having HDM allergen levels associated with the risk of developing allergy sensitization and asthma were 65% and 25%, respectively. Specific antigens of the storage mite and cockroach were only found in samples from the southern and tropical regions of China. Levels of mite allergens were generally higher in samples from bedding compared to samples from the living room, even for storage mites, whereas levels of cockroach antigens were higher in the living room samples.Conclusion HDM allergens are present in bedding dust samples from most Chinese households. Cities in southern and central China have relatively high levels of HDM major allergens compared to cities in northern and western China. Antigens of storage mites and cockroaches are not as common as HDM allergens.
基金financially supported by the National Natural Science Foundation of China (No. 41977341)Natural Science Foundation of Zhejiang Province, China (No. LGF21B070007)Research Center for Air Pollution and Health, Zhejiang University (No. I21405-11)
文摘Air pollutants can potentially lead to nitration of allergic proteins,thus promoting sensitization of these allergens.However,little is currently known about the nitration status of house dust mite(HDM)allergens.We identified the occurrence of nitrated products of two major HDM allergens Der f 1 and Der p 1 in dust samples collected from college dormitories in eastern China and assessed their associated health risk.The results showed that both non-nitrated and nitrated forms of the two allergens were detected in the dust in the range of non-detected(ND)-10.6,1.44-15.4,ND-22.4,ND-7.28μg/g for non-nitrated Der f 1,nitrated Der f 1,non-nitrated Der p 1 and nitrated Der p 1,respectively.The median rates of nitration were determined as 74.0%for Der f 1 and 20.4% for Der p 1 at consideration of one nitration site.Further analysis reveals that the levels of HDM allergens and their nitrated products were found to be generally higher during winter,in dormitories of lower altitude and with female occupants.Furthermore,the calculated risk indexes were at considerably high levels.Our findings suggest that nitrated HDM allergens have already accumulated in the environment at such significant levels and their associated health risk calls for our immediate attention.
基金supported by the Czech Science Foundation as project 17-12068S.
文摘The interaction of house dust mites(HDM)and microorganisms is the key factor in the survival of these mites in human-made environments.Spent growth medium(SPGM)provides the rest of the dict,along with dead mite bodies and microorganisms.SPGM represents a source of microorganisms for the recolonization of mite food and the mite digestive tract.An experiment was performed to observe how adding SPGM to the HDM diet affects HDM population growth,the microbiome composition and the microbial respiration in microcosms.We analyzed American house dust mite(Dermatophagoides farinae)and European house dust mite(Dermatophagoides pleronyssinus)originating from control diets and diets treated with an extract of SPGM from 1-and 3-month-old mite cultures.The microbiome was described using 16S and 18S barcode sequencing.The composition of the bacterial and fiungal microbiomes differed between the HDM species,but the SPGM treatment influenced only the bacterial profile of D.farinae.In the D.farinae microbiome of specimens on SPGM-treated dicts compared to those of the control situation,the Lactobacillus profile decreased,while the Candinium,Staphylococ-cus,Acinetobacter,and Sphingomonas profiles increased.The addition of SPGM extract decreased the microbial respiration in the microcosms with and without mites in almost all cascs.Adding SPGM did not influence the population growth of D.farinae,but it had a variable effect on D.pteronyssimus.The results indicated that the HDM are marginally influenced by the microorganisms in their feces.
文摘目的:观察舌下免疫治疗(SLIT)疗效与尘螨组分sIgE和sIgG4水平变化的相关性。方法:回顾性分析2018年4月~2021年10月就诊于某院过敏反应科并行SLIT的过敏性鼻炎患儿(n=37),根据治疗1年后症状和药物综合评分(CSMS)分为控制稳定组(n=25)和控制不稳定组(n=12),比较两组患儿9种重要尘螨致敏蛋白组分(Derp1/Derf1、Derp2/Derf2、Derp5、Derp7、Derp10、Derp21和Derp23)sIgE和sIgG4的水平变化。结果:Derp1/Derf1和Derp2/Derf2为主要致敏蛋白组分,其治疗前sIgE阳性率为86.5%~94.6%,其中Der p 2的sIgE浓度高于Derp1(P<0.0001)、Derp5(P<0.001)、Derp7(P<0.001)、Derp10(P<0.001)、Derp21(P<0.01);Derf2的sIgE浓度高于Derf1(P<0.0001)、Derp5(P<0.0001)、Derp7(P<0.0001)、Der p 10(P<0.0001)、Der p 21(P<0.0001)和Der p 23(P<0.01)。治疗前Der f 2的sIgG4浓度高于其他组分(P<0.0001),控制不稳定组中Der f 1的sIgG4阳性率(33.3%)高于控制稳定组(4.0%,P<0.05),且控制不稳定组中Derf1和Derp10的sIgG4浓度高于控制稳定组(P<0.05)。治疗1年后,控制稳定组患儿Der f 1和Der p 2的sIgG4水平高于治疗前(P<0.05)。结论:尘螨致敏过敏性鼻炎患儿应用SLIT治疗后,Der f 1和Der p 2的sIgG4浓度升高明显,提示SLIT疗效较好,为临床评估SLIT疗效提供了线索。
文摘Background Subcutaneous specific immunotherapy has been demonstrated to be capable of inducing T-cell regulatory response.Interleukin-10 （IL-10） plays a crucial role in inducing allergen-specific tolerance.However the reports of the changes of IL-10 in house dust mite （HDM）-specific immunotherapy were varied.The aim of this study was to evaluate the function of IL-10-secreting regulatory T cells in asthma children successfully treated with HDM immunotherapy.Methods Peripheral blood mononuclear cells （PBMCs） were isolated from 27 patients following 1.5--2 years of HDM-specific immunotherapy （SIT, SIT group） and from 27 matched treated asthmatic children allergic to HDM （asthmagroup）.After 48 hours of in vitro stimulation with HDM extracts, IL-10-secreting regulatory T cells were measured by four colour flow cytometry.Sera were tested for allergen-specific IgG4 and IgE using the Immuno CAP 100 assay.Results PBMCs from children undergoing immunotherapy following HDM extracts stimuli produced significantly more IL-10 compared with the asthma group.The frequency of iTreg cells and aTreg cells increased in SIT group after HDM stimulation, while it was not affected in the asthma group.Among the iTreg cells and aTreg cells, the frequency of CD4＋CD25-Foxp3-IL-10＋ Treg cells increased the most which was 2 times higher than that in unstimulated cultures in SIT group.The levels of HDM-specific IgG4 of SIT group was significiently higher compared with asthma group, but there was no correlation of the levels of HDM-specific IgG4 and IL-10 secreting Treg cells.Conclusions HDM-specific immunotherapy can successfully upregulate the frequency of IL-10-secreting Treg cells.CD4＋CD25-Foxp3-IL-10＋ Treg cells may play a key role in inducing the immune tolerance in HDM-specific immunotherapy.
基金support by University of Orleans,la Region Centre(HabitAsthmeN8201200073535)and Conseil General45 to F.M.as PhD fellowship.
文摘The cysteine protease caspase-1(Casp-1)contributes to innate immunity through the assembly of NLRP3,NLRC4,AIM2,and NLRP6 inflammasomes.Here we ask whether caspase-1 activation plays a regulatory role in house dust mite(HDM)-induced experimental allergic airway inflammation.We report enhanced airway inflammation in caspase-1-deficient mice exposed toHDMwith a marked eosinophil recruitment,increased expression of IL-4,IL-5,IL-13,aswell as full-length and bioactive IL-33.Furthermore,mice deficient for NLRP3 failed to control eosinophil influx in the airways and displayed augmented Th2 cytokine and chemokine levels,suggesting that the NLPR3 inflammasome complex controls HDM-induced inflammation.IL-33 neutralization by administration of soluble ST2 receptor inhibited the enhanced allergic inflammation,while administration of recombinant IL-33 during challenge phase enhanced allergic inflammation in caspase-1-deficient mice.Therefore,we show that caspase-1,NLRP3,and ASC,but not NLRC4,contribute to the upregulation of allergic lung inflammation.Moreover,we cannot exclude an effect of caspase-11,because caspase-1-deficient mice are deficient for both caspases.Mechanistically,absence of caspase-1 is associated with increased expression of IL-33,uric acid,and spleen tyrosine kinase(Syk)production.This study highlights acritical role of caspase-1 activation andNLPR3/ASCinflammasomecomplex in the down-modulation of IL-33 in vivo and in vitro,thereby regulating Th2 response in HDM-induced allergic lung inflammation.
文摘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.
文摘过敏原的硝基化会引起其致敏潜能的增强,进而带来更大的致敏性健康风险.过敏原蛋白质通常含有多个酪氨酸硝基化位点,分析过敏原硝基化的位点选择性是探究硝基化对过敏原致敏性影响的重要基础.本文以尘螨过敏原为研究对象,建立了基于超高效液相色谱-串联质谱(UPLC-MS/MS)同时定量分析3种尘螨过敏原(Der f 1、Der p 1和Der p 2)的13个酪氨酸位点硝基化程度的方法,并应用于分析3种尘螨过敏原在过氧亚硝酸盐硝基化作用下的位点选择性.结果表明,3种尘螨过敏原均发生了位点特异性的硝基化,Y195、Y37和Y92分别为Der f 1、Der p 1和Der p 2中反应活性最高的硝基化位点.尘螨过敏原位点选择性的硝基化表明,在评价硝基化尘螨过敏原的致敏性变化时应当考虑其位点特异性的硝基化状况.
