粉尘螨Der fI变应原的免疫化学特征鉴定

作者在原制备Der f Ⅰ变应原基础上进行其免疫化学特征鉴定。Der fⅠ的交叉免疫电泳(CIE)结果证实提纯的Der f Ⅰ为均质性。Der f Ⅰ氨基酸组成与Dandeu(1982)、Heymann(1986)报道的Der f Ⅰ相应结果相关性比较表明,三者在氨基酸组成上有相似性。采用放射性变应原吸附试验(RAST)检测55份螨过敏性患者血清抗Der f ⅠIgE抗体水平,其中49.09％病人RAST阳性,平均阳性特异性IgE水平为6.58±3.90百分结合率。结果表明Der f Ⅰ是粉尘螨主要的变应原。     

T-cell sensitization to epitopes from the house dust mites Dermatophagoides pteronyssinus and Euroglyphus maynei

Background Dermatophagoides pteronyssinus and Euroglyphus maynei frequently occur in house dust but little is known about primary sensitization to the less abundant E. maynei. Objective To determine the occurrence of primary sensitization to E. maynei by T-cell responses and the crossreactivity to D. pteronyssinus. Methods The proliferative response ot peripheral blood cells to overlapping peptides from Derp I and Eur m 1 were measured as well as to peptides from Der f 1, an allergen not found in the study environment. Results The most frequent and strongest responses were to Der p 1 peptides especially in the region 105–133. However, 3/17 responders to mite peptides were stimulated predominantly by Eur m 1 peptides and a further two had their highest response to an Eur m 1 peptide. There was very little crossreactivity between Der p 1 and Eur m 1 peptides and very little response to peptides from Der f 1. Conclusion E. maynei group 1 allergens are a significant source of primary T-cell sensitization and have little T-cell crossreactivity with D. pteronyssinus or D. farinae.     

Dermatophagoides-induced interleukin-10 production by peripheral blood lymphocytes from patients with asthma in remission

Interleukin (IL)-10 is a cytokine that regulates inflammatory responses. We studied the role of IL-10 in the development of tolerance to Dermatophagoides farinae in asthma patients in remission, since asthma improves in most children during adolescence. The spontaneous production of IL-10 by cultured peripheral blood mononuclear cells (PBMC) was higher in patients with active asthma than in normal subjects. IL-10 production decreased when 1 microg/ml D. farinae was added to cultures, but increased again in a dose-dependent manner when higher concentrations of D. farinae were added. In patients with remission of asthma, IL-10 production was lower than in patients with active asthma. However, production of IL-10 showed a reciprocal increase in the presence of 1 microg/ml D. farinae, and decreased again at 10 and 50 microg/ml D. farinae. Such alterations were not observed in normal subjects. Cell lines established from patients asthma in remission showed higher IL-10 production when compared with that by cell lines from normal subjects or patients with active asthma when the cells were stimulated by D. farinae at 1 or 10 microg/ml. Neutralization of IL-10 led to revival of the D. farinae-specific proliferative response of PBMC from patients in remission, which was otherwise decreased. The increase of IL-10 production stimulated by D. farinae was inhibited by addition of an anti-IL-10 antibody. In contrast, antigen-induced interferon (IFN)-gamma production, which was increased by D. farinae stimulation when patients were in remission, did not increase after treatment with anti-IL-10, although spontaneous IFN-gamma production increased to the level seen after D. farinae stimulation. The reduced IL-4 production by cells from patients in remission after stimulation with D. farinae antigen, which was significantly higher in active patients, was not reversed by neutralization of IL-10. The D. farinae-induced IL-10/IL-4 production ratio, but not the IL-10/IL-5 production ratio, may be a significant indicator for evaluation of whether a patient has been in remission. In conclusion, D. farinae-specific anergy of T cells is likely to be induced by increased levels of IL-10 and IFN-gamma that are initially produced by specific T cells after exposure to relevant mite allergen in patients in remission.     

Biologic activity of Dermatophagoides siboney and Blomia tropicalis allergens in exposed and unexposed mite‐allergic individuals. Effect of patient selection on the biologic standardization of mite extracts

BACKGROUND: This study aimed to investigate the influence of patient selection criteria, i.e., mite-allergic individuals exposed and not exposed to Dermatophagoides siboney and Blomia tropicalis, on the biologic activity of mite extracts. Determination of the potency of mite extracts in vivo requires selection of patients with a clinical history of mite allergy. In Scandinavia, there are some anamnestic criteria for mite allergy, whereas in the tropics, where patients are continuously exposed to high levels of mites, selection of patients with mite allergy by clinical history is difficult. METHODS: A total of 210 Cuban asthmatics with continuous symptoms, and 43 Swedes with a clinical history of mite allergy were investigated. Skin prick tests were performed with D. siboney, D. pteronyssinus, D. farinae, B. tropicalis, Acarus siro, Lepidoglyphus destructor, and Tyrophagus putrescentiae extracts. For analysis of the biologic activity of mite extracts, Cuban patients were divided into four groups: 1) all patients skin-test-positive to mites 2) patients positive to mites, but not to other inhalant allergens 3) patients reacting most to the mite species analyzed 4) patients reactive only to mites and reacting most to the mite species analyzed. The biologic potency was calculated according to the Nordic Guidelines. RESULTS: Due to cross-reactivity between mites, Swedish mite-sensitive patients, with a clear clinical history of mite allergy, but not exposed to D. siboney and B. tropicalis, were more skin reactive to these mites than were Cubans. The estimated potency increased gradually to >200% in group 4. In group 1 Cubans, the reactivity to all mites but B. tropicalis was lower than that in mite-sensitive Swedes. CONCLUSIONS: According to the influence of patient selection criteria on the estimation of the potency of mite extracts, the determination of the biologic activity of allergenic extracts in subjects without a clear-cut clinical history should be replaced by new methods when available.     

Lymphocyte proliferative responses to the purified Dermatophagoides farinae major allergen in untreated and hyposensitized atopic patients

We investigated the proliferative response of lymphocytes from mite-sensitive patients (RAST D.far greater than 3.5 PRU/ml) in the presence of the major allergen Der.f.I purified from Dermatophagoides farinae. Comparative studies were carried out with peripheral blood mononuclear cells from non-atopic donors (RAST = 0), and from patients undergoing hyposensitization treatment (5 to 24 months). According to Student's t-test, there was no significant difference in the Der.f.I-induced proliferation of peripheral blood mononuclear cells from normal donors, untreated atopic patients and hyposensitized patients. In conclusion, it was impossible to discriminate between normal donors, atopic patients and hyposensitized patients with regard to their circulating lymphocyte responses to the purified major allergen Der.f.I.     

Effect of germicidal UV-C light(254 nm) on eggs and adult of house dustmites,Dermatophagoides pteronyssinus and Dermatophagoides farinae (Astigmata: Pyroglyhidae)

Objective

To examined the immediate and 24 hours post- irradiation germicidal effects of UV-C lamp on eggs and adults of house dust mites Dermatophagoides pteronyssinus (D. pteronyssinus) and Dermatophagoides farinae (D. farinae).

Methods

This study investigated the immediate and 24 hours post irradiation mortalities of adult mites exposed to UV-C at different exposure times (5 mins, 10 mins, 15 mins, 20 mins, 30 mins and 60 mins) and distances (10 cm, 25 cm, 35 cm, 45 cm and 55 cm). Fresh eggs of the 2 dust mites were also irradiated at 10, 35 and 55 cm for 0.5, 1, 2, 3, and 5 minutes, and observed daily post- irradiation for up to 7 days.

Results

Highest immediate mortality of 100% occurred with direct irradiation at 10 cm distance from UV-C lamp and for 60 mins, for both species of mites. The post 24 hours mean mortality rates were (58.4±17.4)% for D. pteronyssinus and (27.7±9.7)% for D. farinae when irradiated for 1 hour at 55 cm distance under UV-C lamp. When mites were irradiated in the presence of culture media, the highest mortality rates were lower compared to the direct irradiation; at 10 cm distance and 60 mins exposure, the mean mortality was (74.0±6.8)% for D. pteronyssinus and (70.3±6.7)% for D. farinae. Egg hatchability for both species of mites was also notably reduced by greater than 50% following irradiation.

Conclusions

Ultraviolet C irradiation is lethal to an array of organisms by damaging their nucleic acids (DNA and RNA). This study demonstrates the increasing mite mortalities with increasing exposure times and decreasing distances.     

丁香花蕾油对粉尘螨杀灭活性的研究

用索氏提取法以石油醚为溶剂提取制备丁香花蕾中的挥发油组分,用直接接触法和熏蒸法分别测试不同剂量和不同作用时间丁香花蕾油对粉尘螨的杀灭活性,结果显示12.20 μg/cm²丁香花蕾油直接接触粉尘螨后2.5 h死亡率即达100.0%,相同剂量的丁香花蕾油在相对封闭的容器中熏蒸24 h后,螨虫死亡率为100.0%,表明丁香花蕾油对室内粉尘螨具有较好的杀灭活性。     

CD4+ CD30+ T cells perpetuate IL-5 production in Dermatophagoides pteronyssinus allergic patients

BACKGROUND: Airway allergic diseases are regulated by interleukin (IL)-5, which causes infiltration of eosinophils into the bronchial epithelium, and by IL-4 which increases serum immunoglobulin E (IgE) production and promotes CD30 expression on Th cells. CD30 generates a costimulatory signal involved in apoptosis or cell proliferation, depending on the microenvironment. Our aims were: (i) to analyze if CD4+ CD30+ T cells from allergic patients proliferate in response to Dermatophagoides pteronyssinus, and (ii) if upon stimulation this cell population produces IL-4 and IL-5. METHODS: Peripheral blood mononuclear cell (PBMC) from 17 allergic rhinitis and mild allergic asthma patients and 12 healthy nonallergic individuals were stimulated with allergen in the presence or absence of anti-IL-4, anti-IL-5 or anti-IL-4Ralpha monoclonal antibodies (mAbs). TdT-mediated dUTP nick end-labeling (TUNEL) assay, 7-aminoactinomycin-D (7-AAD) intercalation, and flow cytometry were used to determine the CD4+ CD30+ blasts percentage, cell proliferation, apoptosis, and intracellular cytokines after 7 culture days. RESULTS: Cell proliferation induced with allergen showed that 90% of the allergen-stimulated blasts were CD4+, 50% of which were CD30+. Allergen-stimulated PBMC showed a progressive increase (mean: from 7% to 23%) of CD4+ CD30+IFN-gamma+ and CD4+ CD30+IL-4+ blasts which diminished (mean: 6%) after 5 culture days. In contrast, CD4+ CD30+IL-5+ blasts showed a continuous progression (from 12% to 24%) that maintained after 7 culture days. The vast majority of CD4+ CD30+ blasts were negative to 7-AAD or TUNEL. Additionally, a significant decrease (34%) was observed in the number of CD4+ CD30+ blasts when IL-4 was neutralized. CONCLUSIONS: These data suggest that specific allergen stimulation of PBMC isolated from allergic patients generates a nonapoptotic CD4+ CD30+ blast subset that produces IL-5.