Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.22.65 (Der p 1)
 346 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To establish a guinea pig model for house dust mite allergy with purified mite allergens, we studied the immune response to two major mite allergens, native Der f 1 (nDer f 1) and recombinant Der f 2 (rDer f 2) and crude mite extract in Hartley guinea pigs. Animals were immunized with either mite extract, nDer f 1 or rDer f 2, four times at 2- to 3-week intervals. Then the guinea pigs were examined as to the status of sensitization to the sensitizing antigen. Intradermal injection of mite antigens to mite extract-, nDer f 1-, and rDer f 2-sensitized animals induced both immediate and late-phase cutaneous reactions. Allergic airway disease was also provoked by the intranasal instillation of rDer f 2 or mite extract. Anti-nDer f 1 and -rDer f 2 IgE as well as anti-mite extract IgE were produced in the sensitized guinea pigs and IgE titer for three mite antigens were comparable. We concluded that immunization of Hartley guinea pigs with nDer f 1 and rDer f 2 achieved sensitization to mite allergens, which was comparable to that obtained by the immunization with mite extract. A mite-allergic model suitable for immunological and pharmacological studies was established from rDer f 2-sensitized guinea pigs.
 ...
PMID:Induction of allergic reactions in guinea pigs with purified house dust mite allergens. 1008 87

The presence of mite allergens in dust can be determined by counting mites at different stages of development in dust and by determination of the major allergen content (Der p 1 ) in dust and air, which is crucially important to allergic patients. For comparison of results, similar methods for collection of dust and air must be used. Due to their size, mite bodies and fecal particles are airborne only directly after disturbance. Special filters should be used for dust collection, and upholstered surfaces should be vacuumed for 2 min/m2 (minimum 4 m2) and hard surfaces for 1 min/m2 (minimum 8 m2). Heavy contaminations should be removed. Preferably, the method given in the ISAAC study should be followed. Samples should be deep-frozen for at least some days to kill the mites. ELISA techniques, preferably using polyclonal antibodies and antigen with all isoforms present, should be used for determination of allergens. The allergen load has been given in ng/g of dust, but allergen/m2 or per sample area should be preferred. Allergen in the air should be given in pg/m3. A tentative limit of 2000 ng/g was proposed for sensitization and asthma. This limit is still valid on a population basis, but recent data indicate that highly susceptible young children become sensitized at concentrations 10-100 times lower and that ng levels of cat allergen/m3, as found in schools, induce chronic asthma.
 ...
PMID:Mite allergens. Collection, determination, expression of results, and risk levels for sensitization and symptom induction. 1009 16

Allergic reactivity to house-dust mites (HDM) can be detected in patients with atopic eczema by prick and patch test challenge. To determine the clinical relevance of this reactivity, we performed a placebo-controlled, double-blind trial of anti-HDM measures. Active treatment comprised Gortex bags for all the bedding elements, a high-powered vacuum cleaner, and a spray containing benzyl alcohol and tannic acid to kill mites and denature allergens. Placebo treatment was light cotton bags, a cheap vacuum cleaner, and water spray. Forty-eight patients (28 active group) completed the trial, which lasted 6 months. Dust was sampled from the mattress surface and bedroom and living-room carpets before and at monthly intervals after institution of the measures. Dust was weighed and Der p 1 determined by ELISA (ALK). Patients were assessed for area and severity of eczema by a blinded observer. There was a highly significant reduction in bed surface dust - most beds yielded insufficient dust to extract and assay. Carpet Der p 1 levels were reduced to similar minimal levels by both active and placebo treatments (about 250 ng/m2). There were highly significant benefits on the eczema scores, the active treatment being greatly superior to placebo (P< or =0.0006; analysis of covariance). In conclusion, Gortex bed bags were highly effective at containing dust within the bed. This was associated with clinical improvement in most patients with atopic eczema - the biggest improvements were seen in the most severely affected subjects.
 ...
PMID:Mite elimination--clinical effect on eczema. 1009 18

The aim of the present study was to examine the in vivo effect of interleukin (IL)-12 on a murine model of asthma induced by Dermatophagoides pteronyssinus-derived Der p 1 allergen. C57BL/6 mice immunized with Der p 1 allergen adsorbed to alum/pertussis toxin developed a T-helper type 2 (Th2)-dominant immune response characterized by the presence of IgE antibody, airway eosinophil infiltration and increased production of Th2 cytokine. Intraperitoneal injection of IL-12 (1 or 0.1 microg per day) for 5 days (day -1 to +3) simultaneously with each immunization, inhibited the production of IgE and IgG1 antigen-specific antibodies, whereas production of IgG2a was strongly enhanced. In addition, mice receiving both doses of IL-12 showed a strong inhibition of IL-5 but up-regulation of IFN-gamma production by spleen cells stimulated with antigen. Administration of IL-12 also prevented antigen-induced eosinophil infiltration into the bronchoalveolar area in a dose-dependent manner and the primary inflammatory mediator serotonin in bronchoalveolar lavage (BAL) fluids was also reduced significantly. Taken together, the data indicate that IL-12 has a potent immunomodulatory effect on house-dust-mite-induced allergic disorders and may be used as an efficient agent for immunotherapy.
 ...
PMID:Administration of interleukin-12 prevents mite Der p 1 allergen-IgE antibody production and airway eosinophil infiltration in an animal model of airway inflammation. 1010 39

A multicentre, prospective cohort study of childhood asthma was established in three European countries; the purpose of the project is the examination of factors which modify the relationship between allergen exposure in infant life and subsequent atopy and asthma. Dust samples were collected from the homes of 643 infants in a single town in the UK (the first cohort) and assayed for house dust mites (Der p 1) and cat allergen (Fel d 1) concentrations by enzyme-linked immunosorbent assay. A questionnaire with potential relevance to the development of atopy and asthma was completed. A wide variation in exposure to both allergens was observed. Carpeted, double-glazed or damp living rooms, and those sampled in the winter months, had higher levels of Der p 1, but these features did not predict Fel d 1 concentrations. Measures of high home occupancy were positively related to Der p 1 concentrations; and inversely with levels of Fel d 1, a finding which could not be explained by cat ownership. Homes in which one or more persons smoked had significantly lower concentrations of Der p 1, but not Fel d 1. There were no consistent differences in allergen levels between homes where one or more parent or sibling was either atopic or asthmatic. These findings indicate complex interactions among domestic, behavioural and seasonal factors and early allergen exposure in British children.
 ...
PMID:Domestic aeroallergen exposures among infants in an English town. 1023 30

In asthma, it is uncertain whether there is an association between degrees of exposure to domestic allergens and asthma severity. The pattern of sensitivity and exposure to common indoor allergens was examined in subjects with differing asthma severity. Sensitivity to house dust mite, dog and cat allergen and exposure to Der p 1, Can f 1 and Fel d 1 were assessed by skin prick tests and settled dust analysis in 28 subjects with severe asthma and 28 age- and sex-matched subjects with mild asthma (two declined skin prick test). All severe asthmatic subjects had at least one positive skin test and 20 of the 28 subjects were positive to all three allergens. Fourteen of the 26 subjects with mild asthma who took skin prick tests were positive to at least one, and one of these subjects was positive to the three allergens tested. Except for bedroom Fel d 1, the proportion of severe asthmatics both sensitized and exposed to each allergen at each site was significantly greater than the proportion sensitized and exposed in the mild asthma group. The geometric mean allergen concentrations, with the exception of bedroom Fel d 1, were greater in sensitized severe asthmatics than the sensitized mild asthmatics, which was significant for Der p 1 in bedroom samples and Can f 1 in bedroom and living room samples. These results support an association between the degrees of domestic allergen exposure in sensitized individuals and asthma severity.
 ...
PMID:Sensitivity and exposure to indoor allergens in adults with differing asthma severity. 1023 42

Several studies, in particular in adult groups, have evaluated the involvement of mites in the pathogenesis of atopic dermatitis (AD). This still remains controversial. The objective of this study was to determine the level of house dust mites (HDMs) in the beds of a group of children with AD and correlate these levels with their allergometric assessment. Forty-one children with AD underwent allergometric tests (prick test, patch test and radioallergosorbent test, RAST) and the concentration levels of HDMs in their homes were evaluated. Our data show that about half of the children (51%) with AD presented Dermatophagoides pteronyssinus positivity (prick test and/or RAST and/or patch test). Dust was collected in the period October-November from the children's beds, by the same two operators, using a dust-collection device. The dust mite level was tested by an enzyme-linked immunosorbent assay with antibody against Der p 1 allergen. Ten children (24%) presented a Der p 1 concentration > 2 microgram/g of dust (the value assumed to be a risk level for sensitization), 20 (49%) between 0.1 and 2 microgram/g and 11 (27%) < 0.1 microgram/g of dust. In the group with the highest Der p 1 concentration (> 2 microgram/g dust) nine children (90%) presented an allergometric D. pteronyssinus sensitivity, the difference with the other two groups being statistically significant at P < 0.018. The results of the present study show that the highest HDM concentrations were observed in the group with an allergometric D. pteronyssinus positivity (prick test and/or RAST and/or patch test). It is hypothesized that a higher HDM concentration may elicit D. pteronyssinus IgE sensitization and delayed hypersensitivity in children with AD.
 ...
PMID:Mite allergen (Der p 1) levels in houses of children with atopic dermatitis: the relationship with allergometric tests. 1023 15

A double-blind, placebo-controlled study was carried out in 85 patients with a well-documented history of perennial asthma caused by house-dust mites. Patients received either placebo or sublingual immunotherapy (SLIT) with a standardized Dermatophagoides pteronyssinus (DP)-D. farinae (DF) 50/50 extract. After a run-in period, patients received increasing doses up to 300 IR every day for 4 weeks and then three times a week for the following 24 months. The cumulative dose was about 104000 IR, equivalent to 4.2 mg Der p 1 and 7.3 mg Der f 1. Symptom and medication scores and respiratory function were assessed throughout the trial. Serum specific IgE and IgG4 were determined before SLIT (t0) and after 6 (t1), 11 (t2), 17 (t3), and 25 months (t4) of SLIT. Mite exposure was evaluated at t0, t2, and t4 by semiquantitative guanine determinations. Patients aged 15 years and older were asked to assess their quality of life (QoL) by completing the SF20 (Short Form Health Status Survey) plus two items at t0, t2, and t4. Use of inhaled corticosteroids and beta2-agonists was significantly decreased after 25 months of treatment in both groups (P<0.03). SLIT patients showed significant improvements in respiratory function at t4 (% predicted FEV1 (P = 0.01), VC (P = 0.002), morning (P = 0.01) and evening (P = 0.03) PEFR), and reduction in daytime asthma score (P = 0.02). In the SLIT group, the post-treatment PD20 was 1.75 times higher than the baseline value. There was no change in PD20 in the placebo group. Compared to the placebo group, the SLIT group showed a significant increase in specific IgE DP(P = 0.05), IgE DF(P = 0.02), IgG4 DP(P = 0.001), and IgG4 DF (P = 0.001) levels after SLIT. QoL scores were similar in both groups at t0 and t2. At t4, all scores were better in the SLIT group than in the placebo group, with the differences being most marked for the general perception of health (P = 0.01) and physical pain (P = 0.02). Adverse events were similar in the two groups. This study shows that SLIT in house-dust-mite-related asthma has a good safety profile and improves respiratory function, bronchial hyperreactivity, and QoL.
 ...
PMID:Sublingual-swallow immunotherapy (SLIT) in patients with asthma due to house-dust mites: a double-blind, placebo-controlled study. 1032 61

In an analysis of murine immune responses to the dust mite allergen Der p 1, treatment with purified allergen induced a significant increase in the level of circulating IgE immunoglobulin (from less than 100 ng/ml in normal mice to 1,350 ng/ml in mice receiving the allergen). Even so, specific IgE antibodies binding to purified Der p 1 were not detected in a conventional ELISA, and the major response appeared to be the induction of high titre IgG antibodies. Specific circulating murine IgE antibodies were however detected using the following assay format: murine IgE was captured to anti-murine IgE antibody coated wells; Der p 1 was added and bound by immobilized anti-Der p 1 IgE antibodies; the captured Der p 1 was then detected by the addition of monoclonal IgG antibodies against Der p 1 and these antibodies were measured by the addition of anti-murine IgG antibody-enzyme conjugate with which colour development is produced after substrate addition. This assay establishes a procedure to measure circulating anti-Der p 1 IgE antibodies which are present together with competing high titre IgG anti-Der p 1 antibodies.
 ...
PMID:Measurement of murine IgE antibody responses to dust mite allergens by in vitro assay. 1034 Dec 93

In a previous dose-titration study of specific immunotherapy (SIT) with a Dermatophagoides pteronyssinus extract in asthmatic patients, we proposed a dose of 3.2 micrograms of Der p and 1/1.6 micrograms of Der p 2 as an optimal maintenance dose. Changes presented by a high-dose immunotherapy group, with a maximum tolerated dose between 4 and 16 micrograms Der p 1, were compared with those of a conventional immunotherapy group, with a maximum tolerated dose of 3.2 micrograms Der p 1 or lower. After 2 years of SIT, both groups achieved the same level of clinical benefit. We now present the results of long-term monitoring of 25 of these patients, covering the 5 years of SIT in which the maintenance dose was set at 3.2 micrograms Der p 1. The aims of the study were firstly to examine if this maintenance dose could sustain the changes induced by immunotherapy in the first 2 years; and secondly, to determine if this dose is clinically effective in patients known to tolerate higher maintenance doses. The clinical severity index (CSI), medication and symptom scores, cutaneous sensitivity and specific IgE and IgG4 to D. pteronyssinus, Der p 1 and Der p 2 were measured. Positive clinical and immunological changes presented in the first 2 years of SIT were sustained (CSI, medication score, specific IgE) or even increased (symptom score, cutaneous sensitivity) after 3 additional years of SIT. In conclusion, a maintenance dose of 3.2 micrograms of Der p 1/1.6 micrograms of Der p 2 induced intense clinical and immunological changes which were sustained during a 5-year course of treatment, even in patients able to tolerate higher doses.
 ...
PMID:Long-term immunotherapy with an optimal maintenance dose of a standardized Dermatophagoides pteronyssinus extract in asthmatic patients. 1035 99


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>