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Immunoblot analysis and comparative IgE responses of atopic patients to extracts of the domestic mite Blomia tropicalis.

BACKGROUND: The domestic mite Blomia tropicalis is found in subtropical and tropical environments, and its clinical importance as a sensitizing agent in allergic disease is widely accepted. OBJECTIVE: To investigate the IgE reactivity to allergens present in extracts of the domestic mite B. tropicalis, and compare the IgE responses to these allergens by asthmatics, patients with atopic dermatitis and allergic rhinitis, as well as nonatopic controls. METHODS: Extracts from B. tropicalis were used for skin tests. The B. tropicalis specific IgE in the serum were measured using the FAST Plus Test and immunoblot analysis. RESULTS: A total of 199 volunteers participated in the study. The data show that 18 out of 29 polypeptide bands present in extracts of this mite species were recognized by the allergic and control sera. Of these allergens, four showed a high IgE binding frequency and had relative molecular weights of 104, 80, 68 and 14 kDa. The 14 kDa allergen demonstrated the highest IgE binding frequency. CONCLUSION: Sera from atopic patients reacted to more allergens than sera from patients controls. Extracts from pure bodies of B. tropicalis contain one immunodominant and three important allergens. A common characteristic between all of the sera tested was the high degree of serum IgE reactivity observed to the 14 kDa allergen.

Adolescent↗

[The relationship of the population dynamics of gamasid mites with the population dynamics of their murine rodent hosts in the Sikhote-Alin].

22,500 mites were collected from 4515 rodents over a period of 5 years in the Sikhote-Alin reserve. The abundance dynamics of 4, out of 5, most numerous species of mites (Laelaps pavlovskyi, L. clethrionomydis, Eulaelaps stabularis, Haemogamasus serdjukovae) depends on the cyclic fluctuations in the number of rodents. A direct connection between the annual and, to some extent, seasonal dynamics of the abundance of parasites and that of their hosts is most distinct in L. pavlovskyi, an epizoon parasite of the large Japanese field mouse. At the same time the abundance of Hg. ambulans, a multihost parasite of small mammals, does not depend on the number of animals. Certain regularities in the abundance dynamics of gamasid mites in connection with that of their hosts, rodents, is discussed on the basis of obtained material and literary data.

Altitude↗

Peculiarities in ontogenesis and reproductive cycle of the mite Varroa jacobsoni (Parasitiformes, Varroidae) and its relation to the host Apis mellifera.

On the basis on functional morphology and ecology of Varroa jacobsoni the reproductive cycle of female mites was divided into 5 stages: copulation, puberty, preoviposition, oviposition, rehabilitation. The whole ontogeny from egg to formed protonymph in the chorion proceeds very intensively (26 to 30 hours). Besides the reproductive potential is realized during an extremely short period (6 to 7 days) which duration is determined by the total duration of the mite's ontogeny, so that the development of adult mites in all of the viable eggs laid has to be completed by the time the bees leave the brood.

Animals↗

[Evaluation of different treatments of Japanese bed quilts for reducing mite allergens].

We evaluated the effectiveness of different treatments of Japanese bedquilt (futon) in reducing mite allergens: vacuum-cleaning, beating plus vacuum-cleaning and washing of the whole futon in water. Before and after these treatments, small amounts of cotton were taken out of the futon and mite allergens were extracted from the cotton into water. The absolute contents of two kinds of major allergens of two Dermatophagoides species were immunochemically quantitated. We found that beating and vacuum-cleaning reduced the allergen contents by only about 40%, whereas washing reduced the allergens by more than 90%. Therefore, for reducing airborne mite allergens generated from futon, we think that washing the whole futon in water is the most effective method.

Allergens↗

[Correlation between nasal polyposis and perennial allergy exemplified by house dust mite and house dust allergy].

A total of 139 patients with nasal polyps were investigated by a standardized history, intradermal skin test and nasal challenge to house dust mite allergy. The aim of the study was to assess the disputed role of perennial allergy in patients with nasal polyps using allergens to the house dust mite as an example. Using our diagnostic criteria we found allergy to house dust mite in 28% of all cases. We found this diagnosis in 44.8% of patients aged 10-39. We recommend, especially in this age group, an allergy test, if necessary with the appropriate therapy. Test correlations are illustrated in 174 patients who have been examined by the above methods. Good reproducibility was found by the nasal challenge, which led to the right diagnosis in 92%, compared with 81% by a standardized history. Therefore, it can be considered to be the key to the diagnosis of allergy.

Adolescent↗

Dermatophagoides mites in house dust as an allergen source in atopic dogs.

Thirty dogs with a clinical diagnosis of atopy were skin tested with 58 allergens including an aqueous house dust mite extract and a crude house dust extract. Sixty percent of the dogs had positive skin reactions to both the house dust mite and house dust antigens. In atopic dogs, house dust mites appear to be an important allergen source in house dust extracts but are not the only major source.

Allergens↗

[Storage mite allergy. Routine tests].

Storage mites are sources of allergy among farmers and silo workers. Among 114 patients with allergic rhinitis we found four with a positive prick test to storage mites. This is not sufficient reason to include storage mites in a standard allergy prick test series.

Adolescent↗

The management of house dust mite allergies.

A safe and practical home sanitation procedure for the removal of house dust mites (Dermatophagoides pteronyssinus) and their allergens is described. The severity of mite infestation was assessed with the use of the Acarex test, which measures the concentration of guanine in house dust, and all affected house textiles were then treated with an Acarosan product. The active ingredient of Acarosan is benzyl benzoate, which has been used as a scabicide for over 100 years. The results of several studies of Acarosan treatment were reviewed and it was concluded that use of the guanine test and Acarosan products allows many sensitized persons to control the concentration of house dust mite allergens in their homes.

Animals↗

Antigen Der f I from the dust mite Dermatophagoides farinae: structural comparison with Der p I from Dermatophagoides pteronyssinus and epitope specificity of murine IgG and human IgE antibodies.

The physicochemical and antigenic properties of an allergen purified from Dermatophagoides farinae, Der f I, were compared with Der p I from Dermatophagoides pteronyssinus. On SDS-PAGE, Der f I migrated as a single polypeptide chain with the same m.w. as Der p I (24,000). Two isoallergenic peaks of Der f I were identified on preparative isoelectric focusing (pI 5.7 to 6.3 and pI 6.6 to 6.95). Fractions from each peak were shown to have an identical amino acid composition (which was similar but not identical to Der p I) and the same N-terminal amino acid sequence. There was a good correlation between quantitative intradermal skin tests to both purified allergens and to D. farinae extract in mite-allergic patients, with positive results when using as little as 10(-5) micrograms/ml of Der f I. The majority of sera with detectable IgE antibody to D. farinae also had IgE antibody to Der f I both among children (29/42 = 69%) and adults (55/63 = 87%). By RAST, there was an excellent correlation between IgE antibody to Der f I and Der p I in sera from 42 mite-allergic children (n = 0.94, p less than 0.001). Polyclonal IgG antibodies from six mice immunized with Der f I showed preferential binding to that allergen, and most monoclonal antibodies (16 of 18) raised against Der f I did not bind Der p I. However, two monoclonal antibodies from this fusion showed cross-reactive binding to both allergens. Immunoabsorption experiments, using D. pteronyssinus and D. farinae extracts coupled to Sepharose, showed that a large proportion of murine antibodies (74% to Der p I and 60 to 93% to Der f I) could not be absorbed by the heterologous extract on the immunosorbent. In contrast, in sera from seven mite-allergic patients, most of the specific IgE and IgG antibody (i.e., greater than or equal to 82%) was removed by either immunosorbent. Thus, Der f I and Der p I represent a homologous pair of major allergens which possess both cross-reacting and species-specific epitopes. The antibody response in mice immunized with either allergen in complete Freund's adjuvant was largely directed against species-specific epitopes, whereas in allergic humans, IgE- and IgG-specific antibodies bound predominately to cross-reacting epitopes.

Allergens↗

Epitope mapping of two major inhalant allergens, Der p I and Der f I, from mites of the genus Dermatophagoides.

The repertoire of antigenic sites on two major dust mite allergens, Der p I of Dermatophagoides pteronyssinus and Der f I of D. farinae, was studied using murine (BALB/c) monoclonal antibodies (Mab), polyclonal rabbit IgG antibodies, and human IgE antibodies. Fifty-three IgG Mab were analyzed from six different fusions (five vs Der p I, one vs Der f I). By antigen binding radioimmunoassay (RIA), most Mab were either Der p I or Der f I specific, and only 2/53 bound to both allergens. Epitope mapping studies using cold Mab to inhibit the binding of six 125I labeled Mab to solid phase allergen defined four nonrepeated, nonoverlapping epitopes on Der p I, a single species-specific epitope on Der f I and a cross-reacting epitope present on each allergen. All but one of the 53 Mab bound to one of these six epitopes. Seventy percent (25/35) of anti-Der p I Mab were directed to the same epitope, suggesting that this epitope is immunodominant for BALB/c mice. Similarly, 88% (16/18) of anti-Der f I Mab bound to the same epitope on Der f I. Parallel cross-inhibition curves were obtained using the species-specific Mab, 10B9, and the cross-reacting Mab, 4C1, to compete for binding to Der p I, suggesting that the epitopes defined by these two Mab on Der p I are adjacent to one another. Both murine Mab and polyclonal rabbit IgG antibodies to cross-reacting sites on both allergens were used to inhibit binding of human IgE antibodies to Der p I by using 19 sera from mite allergic patients. Cross-reacting rabbit IgG antibodies strongly inhibited all sera tested (mean 79.5% +/- 7.7) and two Mab, 10B9 and 4C1, partially inhibited (38% +/- 12). However, the four Mab directed against separate species-specific epitopes (including murine immunodominant sites) showed little or no inhibition (less than or equal to 20%). Our results suggest that most of the epitopes defined by Mab are not the same as, or close to, those defined by human IgE antibody. The striking differences in the repertoires of murine IgG and human IgE antibody responses to Der p I and Der f I could be explained by genetic differences or by altered antigen processing and presentation occurring as a result of different modes of immunization in mice and in mite allergic humans.

Allergens↗

The hair follicle mites (Demodex spp.). Could they be vectors of pathogenic microorganisms?

The hair follicle mites Demodex folliculorum and D. brevis are the most common permanent ectoparasites of Man. Ordinarily they are harmless to their human host and appear to be of no medical significance. We present, however, an unusual finding regarding this mite, namely, that in a potassium hydroxide mount of a skin scraping from a mycotic plaque we found numerous Demodex mites containing inside them spores of Microsporum canis. This could mean that the putatively inoffensive Demodex has the potential to ingest various microorganisms that are found in its niche and transport them to other areas of the skin or possibly to other individuals.

Acari↗

[Nest ectoparasites (gamasid mites) as vectors for rickettsia under experimental conditions].

The author gives a review of occurrence of rickettsiae (Coxiella burnetii, R. slovaca, R. sibirica, R. prowazekii, R. mooseri, R. akari) in gamasid mites, investigated in laboratory or in nature. The results of our experiments and from literature also are summarized in tables. The experimental infection with C. burnetii was investigated by natural route of infection in the following species of mites: Haemogamasus nidi, H. hirsutus, Androlaelaps casalis. We found C. burnetii in smears, stained with Gimenez and IMF, with whole bodies as well as in their excrements. The white mice injected with the suspension from these mites gave the positive serological response.

Animals↗

[Effect of a visit in an eradication environment on reactivity to mites in the respiratory mucus].

33 asthmatic children, stabilised and allergic to mites on a long-term stay at Font-Romeu, were included in a protocol that was intended to show the effect of stay in an environment of natural eradication on the reactivity of the nasal mucosae. 3 groups were formed: A. To receive every day several microgrammes of mites on the nasal mucosae, lasting one month P. Physiological saline T. Left untreated. The reactivity was measured before the test, after one month, then after about another month during which each group was left untreated. The reactivity remained stable in A and T, and reduced in P. The indications were: 1. That the mites (the stay in the infested environment) augmented the reactivity. 2. In the eradication environment it decreased then stabilised itself at a basal level. 3. It then decreased again, due to the effect of the saline.

Adolescent↗

Skin and serum reactivity to some storage mites in children sensitive to Dermatophagoides pteronyssinus.

The incidence of skin test and RAST positivity for Dermatophagoides farinae and storage mites (Glycyphagus privatus, Lepidoglyphus destructor, Tyrophagus putrescentiae, Acarus siro, and Gohieria fusca) have been evaluated in children with bronchial asthma and positive prick test to Dermatophagoides pteronyssinus. The storage mite with highest incidence of skin and RAST positivity was Gohieria fusca, which caused a positive response in more than 50% of the children evaluated. This antigen appears to possess allergenic determinants not present in Dermatophagoides pteronyssinus. The sensitivity to this antigen might be considered in house dust mite-allergic children who do not improve after specific immunotherapy with Dermatophagoides pteronyssinus extracts.

Adolescent↗

[Inhalation mite provocation in atopic patients in relation to high altitude conditions].

The clinical diagnosis of allergy of the respiratory system caused by flour or dust mites--i.e. perennial bronchial asthma and/or allergic rhinitis--hat to be proved by the case history, prick test, RAST, as well as provocative inhalation, before any hyposensitization measures are taken. The mountain climate (above 1500 m) is especially appropriated for these procedures since mites cannot live here. With regard to the pulmonary function and the correlation to RAST, we evaluated 83 specific bronchial and nasal provocative inhalation tests with dust or flour mites performed on patients suffering from atopic dermatitis and allergies of the respiratory system.

Adult↗

House dust mites.

The significant role of house dust mites responsible for health hazards such as respiratory allergy, nasobronchial, and nasal allergy in sensitive individual is well documented. Critical investigations, however, of house dust mite allergy in the tropics are few. The present investigations have helped in locating the source, assessment, quantitative and qualitative estimation, seasonal variations, and effect of meteorologic variables on house dust mite allergy and its relevance to clinical data of patients.

Allergens↗

Dogs hypersensitive to house dust mite.

Active intradermal skin reaction, respiratory resistance and respiratory patterns were examined in five dogs after intradermal injection or inhalation of house dust mite (Dermatophagoides farinae) extract and the results obtained were as follows: 1. Three out of the five dogs exhibited positive skin reactions against house dust mite extract solution at concentrations of 0.1 micrograms/ml to 10 micrograms/ml. 2. Inhalation of mite extract at a concentration of 1 mg/ml by the dogs that had positive skin reactions produced a marked increase in respiratory resistance and changes in spirogram. These results suggest that the dogs that exhibited positive skin reactions were spontaneously sensitized to D. farinae.

Animals↗

[Role of rhinomanometry in childhood mite allergy apropos of 76 cases].

Place for Passive Anterior Rhinomanometry (PAR) in mite allergic children. PAR is a simple method to investigate chronic or recurrent rhinopathies in children. Among 59 investigations with a Dermatophagoides pteronyssinus extract, we found 27 positive responses, 3 doubtful results and 32 negative explorations. Nasal sensitization is usually important: the liminal dose is less than 250 mcg in 17/28 cases. Most children have no bronchial sensitivity. None of 14 children with negative cutaneous and RAST tests have nasal sensitivity. When cutaneous and RAST tests are both positive, 12/16 positive PAR are found. We note a nasal sensitivity in 3/5 cases with only cutaneous test positive and 12/26 cases with only RAST tests positive. For other mites a nasal sensitivity is found in 8 out of 14 explorations (Tyrophagus and Glyciphagus especially). Among all patients when cutaneous tests, RAST tests and history are doubtful for the real part played by mites in the child rhinopathy, nasal exploration allows more explicit diagnostic and therapy.

Adolescent↗