Biomedical subjects

K Mouchián

Publications and source records attributed to K Mouchián.

10 recordsLinked to original sources

PubMedDate not supplied

[Hypersensitiviy to Trichophyton rubrum antigens in atopic and non-atopic podiatrists].

BACKGROUND: Podiatrists as well as manicurists are exposed to inhale nail dust contaminated with mycotic particles when filing and burring the onychomycotic nails of their patients. As some of them with atopic background suffered worsening of their symptoms we decided to study the immune response to the fungus Trichophyton rubrum (Tr) that was isolated from the nail dust obtained from the podiatrists office. METHODOLOGY AND RESULTS: A detailed clinical record, intracutaneous skin tests with a extract of Tr and the serum levels of total and specific IgE were performed in rhinitis-asthma as well as control patients. As the asthmatic group refused to perform the challenge bronchial test with Tr we developed a guinea pig experimental model with daily aerosolization of Tr during 12 weeks studying the levels of specific IgE and IgG as well as the lung's histopathology. Atopic patients showed positive immediate skin tests with Tr and both groups revealed delayed hypersensitivity to the antigen.RAST-IgE-anti-Tr and RAST-inhibition confirmed the specificity of the antibodies. Guinea pigs also synthetized IgG and IgE anti-Tr and suffered different degrees of lung lesions similar to those of hypersensitivity pneumonitis. CONCLUSION: Atopic podiatrists are exposed to fungal allergens that may participate or aggravate their previous respiratory conditions.

Adult↗

PubMedDate not supplied

[Hypersensitivity pneumonitis induced in guinea pigs by antigens to bat feces].

A bat feces extract was able to induce the synthesis of specific IgG in rabbits and IgE in atopics. These findings were corroborated by skin tests, RAST and RAST-inhibition. Nowadays, data concerning the experimental induction of hypersensitivity pneumonitis using a glycoprotein of bat feces are presented. This antigen was aerosolized for inhalation by adult guinea pigs for 12 weeks to detect specific serum IgM, IgG and IgE antibodies as well as sensitized T-CD4 cells. Histopathological studies of the lungs showed interstitial infiltrates of macrophages and lymphocytes, cellular bronchiolitis and single non-necrotizing granulomas from the seventh to the ninth weeks. From the tenth week to the end of the experiment the lesions of the lungs progressively worsened. The results from this animal model suggest that the chronic contact with the bat feces'antigen can induce other inflammatory lung reactions than those IgE dependant.

Aerosols↗

PubMedDate not supplied

Immunological changes during cockroach immunotherapy.

Data obtained in a 3-year survey of specific immunotherapy (SIT) with a Periplaneta americana antigen (Pa-1) are presented. Parameters such as serum IgE-paperadioimmunosorbent test, specific IgE and IgG, interleukin (IL)-2, IL-4 and IL-4R levels were recorded before and after SIT. While serum IgE levels and IgE-RAST-anti-Pa-1 did not change throughout SIT (p = not significant), IgG-RAST-anti-Pa-1 showed a marked increase from the first year (p < 0.002 to p < 0.001). Only after 3 years of SIT did the serum levels of IL-2, IL-4 and IL-4R show lower values than before this period (p = 0.05, p = 0.05, p = 0.01, respectively). The comparative statistical analysis of the cytokine data between the nonatopic subjects and the atopic treated patients revealed no significant differences (p = 0.02). The symptomatic scores showed significant results at the third year of SIT in sneezing attacks, nose blowing and nasal obstruction (p = 0.001, p < 0.001, p = 0.001, respectively).

Adolescent↗

PubMedDate not supplied

Interstitial pneumonitis induced in guinea-pigs by the antigens of Periplaneta americana.

Data concerning the experimental induction in guinea-pigs of hypersensitivity pneumonitis with a cockroach antigen are presented. A glycoprotein obtained from the chitinous structures of Periplaneta americana was aerosolized daily to guinea-pigs during 12 weeks. The presence of specific antibodies (IgG) was detected by serological techniques; histopathological studies of the lungs showed interstitial infiltrates of macrophages and LT-CD8+ cells, as revealed by the MoAb used. Single non-necrotizing granulomas were characteristic from the 10th week to the end of the experiment. The results from this animal model suggest that this hypersensitivity pneumonitis is a typical delayed-type reaction due to chronic contact with the heterologous glycoproteins of P. americana.

Alveolitis, Extrinsic Allergic↗

PubMedDate not supplied

Antigenicity of Penicillium notatum in animals and in atopic patients.

A mycelial and metabolic extract of Penicillium notatum (PN) was passed through Sephadex G-50 and DEAE-cellulose columns in order to separate soluble fractions that revealed a complex composition. Their proteins and hexoses were recorded with a LKB Uvicord spectrophotometer and quantified by the Lowry and the indol techniques. On the other hand an animal model was developed in rabbits and an IgG precipitin and hemagglutinating antibodies were obtained. The PN extract as well as those fractions with the higher protein content appeared positive when they were checked against the antiserum by means of Ouchterlony, Boyden and immunoelectrophoresis. The molecular weight of PN was established in 52,000 daltons approximately in comparison with well known marker proteins. Adult human beings suffering perennial rhinitis and bronchial asthma showed positive type I skin tests with PN and its most conspicuous fractions (glycoproteins). A RAST-IgE-anti-PN was prepared following Ceska's procedure and challenged against all human sera. Only 40% of the patients revealed a positive RAST IgE-anti-PN which correlated significatively with the protein fractions (35%) and with the skin tests (43% and 39%, respectively). These results reinforced the idea that PN is a potent antigenic mold both in animals and in humans in whom we detected an IgE specific antibody presumably related to their atopic clinical condition.

Adolescent↗

PubMedDate not supplied

Immunochemical properties of the antigens involved in the pigeon breeder's disease.

The pigeon breeder's disease is a form of extrinsic allergic alveolitis caused by the exposure to pigeon droppings. Chemical analysis of this antigen was carried out employing column fractionation techniques. Sephadex G-50 and DEAE cellulose were performed and several proteins and hexoses peaks were recorded. Molecular weights were determined by comparison with standardized marker proteins passed through a drop counting fraction collector. The whole extract revealed a molecular weight of 100 Kd while fraction 1 showed 66 Kd and fraction 2 only 30 Kd. A guinea pig experimental model was developed with the whole extract injected by the intradermal route, administered by an intragastric catheter or aerosolized in a glass chamber. Histopathological studies were carried out with the lungs, kidneys, liver and spleen obtained by the necropsy of the animals. The lungs and the kidneys showed the paramount changes in their structures with lymphomononuclear infiltrates and an Arthus-like phenomenon surrounding the vessels. Immunological techniques were applied to the sera and the lymphocytes obtained from the animals. Precipitin and hemagglutinating IgG antibodies were detected against the whole extract and the fractions obtained by column fractionation. Sensitized lymphocytes were also detected. This experimental model represents a guide in the approach to the human allergic alveolitis whose immunological findings will be presented in a forth-coming report.

Alveolitis, Extrinsic Allergic↗

PubMedDate not supplied

Immunochemical properties of the antigens of Blattaria sudamericana.

An extract of the cockroach Blattaria sudamericana (BS), a very common insect in Argentina, was passed through Sephadex G-200 and DEAE cellulose ion exchange columns. This method yielded 2 proteins and 6 hexoses whose quantities were determined by absorbance in a LKB Uvicord spectrophotometer at 280 nm and 470 nm respectively. Protein contents were also recorded by the Lowry method and the micro-Kjehldal technique. Adult albino rabbits were immunized with a mixture of BS and complete Freund's adjuvant over a period of thirteen weeks. The antisera obtained were studied by the Ouchterlony method, the immunoelectrophoresis and the passive hemagglutination technique against BS and the eluated fractions with the highest protein content. Molecular weights were studied with the usual marker proteins subjected to gel filtration by a Sephadex G-200 column. Each protein concentration was 13.5 mg/ml in a volume of 1.5 ml meanwhile BS was 42 mg/ml. This antigen showed a molecular weight of 180,000 daltons. Fifty untreated atopic patients of both sexes with ages between 19 and 74 years suffering perennial rhinitis and bronchial asthma were chosen according to the American Thoracic Society criteria. Their IgE levels ranged between 110 and 3000 KU/L with an average of 620 KU/L. IgE anti-BS-RAST showed positive results in half of the patients while type I positive skin tests with BS 1:100 appeared in 62% of the atopic group.

Adult↗

PubMedDate not supplied

Cross reactivity between the antigens of Periplaneta americana and Triatoma infestans.

The cockroach Periplaneta americana (Pa) and the reduviid Triatoma infestans (Ti) are two very common insects in Argentina that pollute indoor and outdoor environments. They are also strongly immunogenic in animals and in atopic men. Several immunological methods such as serological absorption procedures, diffusion gel methods and capillary electrophoresis were applied in order to establish the existence of common glycoprotein epitopes in the cockroach and in the reduviid. The presence of specific antibodies (IgG & IgE) were detected in rabbits as well as in human sera. The RAST and RAST-inhibition confirmed the cross-reactivity between these two antigens. Capillary electrophoresis evoked similar patterns among Pa, Ti and the moults of the nymphs of Ti. All these findings have clinical and epidemiological importance.

Adolescent↗

PubMedDate not supplied

Interstitial pneumonitis induced in guinea pigs by the antigens of Rhizopus nigricans.

Rhizopus nigricans (Rn) is one of the most common members of the Mucorales that produces opportunistic infections and hypersensitivity states. Data concerning experimental induction in guinea pigs of hypersensitivity pneumonitis with a glycoprotein antigen are presented. This antigen was obtained from the mycelial and metabolic products of the cultures and was aerosolized during 12 weeks. The presence of specific antibodies (IgG and/or IgE) was detected by serological techniques; histopathological studies of the lungs showed interstitial infiltrates of macrophages and LTCD8+ cells, as revealed by the MoAb used. Single non-necrotizing granulomas were characteristic from the tenth week to the end of the experiment. The results from this animal model suggest that hypersensitivity pneumonitis is a typical delayed-type reaction due to chronic contact with the heterologous glycoprotein of Rn. The relation of Rn antigen and the development of occupational diseases of the lung such as malt-worker's lung and wood-trimmer's disease is proposed and discussed.

Administration, Inhalation↗

PubMedDate not supplied

Hypersensitivity pneumonitis induced by Penicillium notatum antigens in guinea pigs.

Data concerning the experimental induction of hypersensitivity pneumonitis in guinea pigs using a glycoprotein derived from Penicillium notatum are presented. This antigen was obtained from the mycelial and metabolic products of the cultures passed through a Sephadex G-50 column. It was aerosolized for inhalation by adult guinea pigs for 12 weeks to detect specific serum IgM, IgG and IgE antibodies as well as sensitized leukotriene CD4 cells. Histopathological studies of the lungs showed interstitial infiltrates of macrophages and leukotriene cells, cellular bronchiolitis and single non-necrotizing granulomas. The results from this animal model suggest that this hypersensitivity pneumonitis is a typical delayed-type reaction due to chronic contact with the heterologous glycoprotein of Penicillium.

Administration, Inhalation↗