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1.
J Clin Invest ; 85(4): 1024-35, 1990 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2318962

RESUMEN

Antigen-antibody complexes were made from allergens of the common house dust mite, Dermatophagoides pteronyssinus (Dpt) and an excess of purified autologous specific antibodies. These complexes have been used to treat Dpt-hypersensitive patients who suffered from chronic bronchial asthma. Clinical symptoms and medication intake were followed by filling in diary cards. Peak expiratory flow, measured four times a day, was also followed. Intradermal skin tests and bronchial challenge tests were performed with allergen together with an evaluation of nonspecific bronchial reactivity. Specific IgE and IgG antibodies were assayed after separation from the bulk of serum immunoglobulins by immunoadsorption. The study was carried out over two years according to a double-blind protocol. Intradermal inoculation of antigen-antibody complexes resulted in a marked reduction of both clinical and medication scores. No systemic side-effects were observed and only mild wheal and flare reactions were noted at the injection site. The treatment showed a drastic reduction of specific skin and bronchial reactivities with only marginal effects on nonspecific bronchial reactivity. Concentrations of specific IgE antibodies decreased significantly during the first weeks of treatment and remained at these lower values throughout the study. Specific IgG antibodies actually decreased in the majority of treated patients. The total amount of allergen used in this study was less than 1% of the amount currently used for conventional hyposensitization with the same allergen. These findings show that antigen-antibody complex inoculation is an efficient and safe means of treating allergic bronchial asthma and that the mechanism of action is likely to differ from conventional hyposensitization.


Asunto(s)
Alérgenos/inmunología , Complejo Antígeno-Anticuerpo/inmunología , Asma/terapia , Hipersensibilidad/terapia , Inmunoterapia/métodos , Ácaros/inmunología , Adolescente , Adulto , Animales , Asma/inmunología , Asma/fisiopatología , Pruebas de Provocación Bronquial , Femenino , Humanos , Inmunoglobulina E/análisis , Inmunoglobulina G/análisis , Masculino , Flujo Espiratorio Máximo , Persona de Mediana Edad , Cooperación del Paciente , Pruebas Cutáneas
2.
Mech Ageing Dev ; 29(1): 35-51, 1985 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3982081

RESUMEN

The alteration of superoxide dismutase (SOD) defined as the change occurring in its thermostability and observed in ageing cells, concerned the cytoplasmic but not the mitochondrial enzymes. Altered SOD disappeared if it was incubated in a supernatant from the young cells whereas supernatants from the old cells induced the alteration. The alteration induced on purified SOD was found to be associated with the appearance of thermolabile tetramers. Cytoplasmic SOD tetramers were also observed in the supernatants of the old cells. The addition of NADPH into the incubation medium could reverse this alteration; also when cultivated in the presence of vincamine the alteration, normally present in the old cells, disappears. The alteration of SOD is therefore associated with the formation of tetramers; it is a reversible process influenced by the cytoplasmic composition of the old cells.


Asunto(s)
Envejecimiento , Fibroblastos/enzimología , Superóxido Dismutasa/metabolismo , Supervivencia Celular , Células Cultivadas , Fenómenos Químicos , Química , Ambiente , Humanos , Vincamina/farmacología
3.
Appl Environ Microbiol ; 48(6): 1181-5, 1984 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16346679

RESUMEN

The alpha- and beta-glucosidase activity in natural samples can be readily measured during short incubation times (20 min) by using the artificial substrates 4-methylumbelliferyl-alpha-d-glucoside and 4-methylumbelliferyl-beta-d-glucoside. The apparent K(m) of both alpha- and beta-glucosidase for these respective substrates is 0.01 muM. The homologous disaccharides maltose and cellobiose competitively inhibit alpha- and beta-glucosidase, respectively. Absolute substrate specificity of the alpha- and beta-glucosidase is observed with respect to the configuration of carbon atoms 1 and 4. Enrichment cultures on either alpha- and beta-glucoside result in increasing activity of the corresponding glucosidase, both in absolute terms and with respect to the other glucosidase.

4.
Appl Environ Microbiol ; 47(2): 424-6, 1984 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-6712213

RESUMEN

Nitrifying activity measurements, carried out on freshly collected samples from an estuarine environment, show that the composition of the nitrifier population undergoes a progressive modification during the mixing of freshwater masses in seawater, with increasing tolerance to salt. As a result, the overall effect of increasing salinity on nitrification is much less severe than the direct effect of salt on the freshwater nitrifying population.


Asunto(s)
Nitratos/biosíntesis , Plancton/metabolismo , Agua de Mar , Aguas del Alcantarillado , Microbiología del Agua , Contaminación del Agua , Agua Dulce , Oxidación-Reducción
5.
Allergy ; 46(5): 335-48, 1991 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1928657

RESUMEN

We have prepared antigen-antibody complexes from grass pollen allergens and autologous specific antibodies isolated by immunoadsorption from the serum of allergic patients. These complexes were inoculated into patients in a double-blind trial to evaluate their effect on grass pollen-related rhinitis and bronchial asthma. Thirty-eight grass pollen-hypersensitive patients were allocated to three groups; patients in the first two groups were treated with antigen-antibody complexes at different ratios and dosages and were compared with the third group who received the placebo carrier buffer alone. In addition, we treated a fourth group who had already received antigen-antibody complex inoculation during the previous pollen season. Injections were given every 2 weeks during the pollen season, starting 5 weeks prior to it. Tolerance was excellent with no signs of local or systemic side effects. The treatment prevented nasal symptoms while enabling the patients to reduce antihistamine intake. Bronchial asthma was virtually absent in the treated groups even though no bronchodilators or corticosteroids had to be taken. Specific IgE antibodies did not increase during the pollen season nor did IgG "blocking" antibodies. Inoculation of allergen-antibody complexes could provide a valuable alternative for the treatment of immediate hypersensitivity to airborne allergens as it appears to be safe and rapidly efficacious. This treatment offers several advantages compared to conventional hyposensitization and is characterized by the absence of an increase in specific IgG antibodies.


Asunto(s)
Complejo Antígeno-Anticuerpo/uso terapéutico , Asma/prevención & control , Inmunoterapia , Polen/inmunología , Rinitis Alérgica Estacional/prevención & control , Adolescente , Adulto , Asma/terapia , Niño , Desensibilización Inmunológica , Método Doble Ciego , Femenino , Humanos , Hipersensibilidad Inmediata/terapia , Inmunoglobulina E/análisis , Inmunoglobulina G/análisis , Masculino , Persona de Mediana Edad , Rinitis Alérgica Estacional/inmunología
6.
J Allergy Clin Immunol ; 83(2 Pt 1): 486-94, 1989 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2918188

RESUMEN

To evaluate parameters that determine the serum titer of specific antiallergen IgE antibodies, we graded the clinical symptoms of 78 grass-pollen hypersensitive patients during two consecutive seasons, while serum total and specific antigrass-pollen IgE antibodies were titrated every 2 weeks. Correlation studies of clinical symptoms, grass-pollen counts, and specific IgE antibodies demonstrated that (1) bronchial asthma and nasal symptoms cannot be predicted on the basis of preseasonal IgE titers, (2) clinical symptoms are not related to seasonal antigrass-pollen IgE antibodies, (3) antigrass pollen and total IgE antibodies are not directly dependent on the air pollen point concentration, (4) increase in specific IgE antibodies during the pollen season is strongly correlated to preseasonal specific IgE titers, and (5) individual fluctuations of specific IgE antibody titers during the pollen season are proportional to preseasonal specific IgE titers. These findings suggest that titration of serum-specific IgE antibodies is of little use in predicting or monitoring the clinical symptoms of grass-pollen hypersensitive patients, since IgE titers strongly depend on individual immune responsiveness.


Asunto(s)
Especificidad de Anticuerpos , Inmunoglobulina E/biosíntesis , Poaceae/inmunología , Polen/inmunología , Rinitis Alérgica Estacional/sangre , Estaciones del Año , Adolescente , Adulto , Niño , Femenino , Humanos , Lolium/inmunología , Masculino , Persona de Mediana Edad , Mucosa Nasal/fisiopatología
7.
Dermatologica ; 182(2): 98-106, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-2050242

RESUMEN

Atopic dermatitis (AD) can be exacerbated by contact with airborne allergens, amongst which Dermatophagoides pteronyssinus (Dpt) appears to be potentially important. Specific IgE antibodies towards Dpt are often found in AD, and it can therefore be speculated that suppression of the production of anti-Dpt IgE might result in a significant clinical improvement. Complexes of antigen and specific antibodies have been shown to suppress the production of antibody in other systems; we report here the evaluation in an open trial of the capacity of such complexes to improve symptoms of AD. Ten adult patients were enrolled in this study. In addition to satisfying the criteria of AD, they all suffered from a severe disease (more than 20% of the body surface involved) that had been stable for at least the last 2 years. The patients had high titers of total IgE antibodies and specific anti-Dpt antibodies. Allergen-antibody complexes were prepared from Dpt allergens and an excess of autologous specific anti-Dpt antibodies obtained by immunoadsorption. The patients received regular injections of these complexes throughout 1 year, during which clinical parameters of disease intensity, percentage of body surface affected and intensity of pruritus were regularly monitored. A significant clinical improvement was obtained after 3-4 months of therapy and was maintained through the 9th month. After 1 year of treatment, 2 patients were completely free of disease, 4 had residual lesions which continued to improve and 4 patients had a partial recurrence of dermatitis.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Alérgenos/administración & dosificación , Anticuerpos/administración & dosificación , Dermatitis Atópica/terapia , Desensibilización Inmunológica , Adolescente , Adulto , Animales , Especificidad de Anticuerpos , Dermatitis Atópica/inmunología , Dermatitis Atópica/patología , Desensibilización Inmunológica/métodos , Femenino , Humanos , Inmunoglobulina E/análisis , Inyecciones Intradérmicas , Masculino , Persona de Mediana Edad , Ácaros/inmunología
8.
Clin Exp Allergy ; 20(6): 653-60, 1990 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2083405

RESUMEN

Complexes made from antigen and specific antibodies have been used to suppress specific antibody production. This property is of potential therapeutic interest in immediate hypersensitivity states which are characterized by hyperproduction of IgE antibodies. We report here on the use of antigen-antibody complexes in patients with hypersensitivity to grass pollen. Specific anti-allergen antibodies were prepared by immunoadsorption from the serum of hypersensitive individuals and mixed with grass pollen allergens to form complexes in antibody excess. These complexes were used in a strictly autologous manner for inoculating patients prior to and during a pollen season. The study comprised two randomly defined groups of 15 patients who were inoculated intradermally either with a preparation of allergen-antibody complexes or with the carrier buffer, according to a double-blind protocol. Diary cards were used to follow nasal and ocular symptoms, bronchial asthma and medication intake. Specific IgE antibodies were assayed during the trial and 1 year afterwards. Inoculation of allergen-autologous antibody complexes was well tolerated. It significantly reduced ocular symptoms (Mann-Whitney U-test, P less than 0.05), bronchial asthma during the first part of the season (Mann-Whitney U-test, P less than 0.001) and drug intake (Mann-Whitney U-test, P less than 0.001). This treatment prevented the seasonal increase in specific IgE antibodies, whose production continued to decrease after the pollen season. These effects were obtained within a few weeks of treatment, using a cumulative amount of allergen 100-fold lower than the amount which would have been used for a conventional hyposensitization.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Alérgenos/administración & dosificación , Complejo Antígeno-Anticuerpo/administración & dosificación , Desensibilización Inmunológica , Rinitis Alérgica Estacional/terapia , Adolescente , Adulto , Especificidad de Anticuerpos , Método Doble Ciego , Femenino , Humanos , Inmunoglobulina E/biosíntesis , Masculino , Persona de Mediana Edad , Polen/inmunología , Rinitis Alérgica Estacional/inmunología
9.
Eur J Immunol ; 24(9): 2134-40, 1994 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7522162

RESUMEN

Human melanoma cell line MZ2-MEL expresses several antigens recognized by autologous cytolytic T lymphocyte (CTL) clones. We reported previously the identification of a gene, named MAGE-1, which codes for antigen MZ2-E which is presented by HLA-A1. Gene MAGE-1 is expressed in many tumors of several types but not in normal tissues except for testis. We show here that gene MAGE-1 directs the expression of another antigen recognized by CTL on the MZ2-MEL cells. This antigen, which was named MZ2-Bb, consists of MAGE-1-encoded peptide SAYGEPRKL bound to major histocompatibility molecule HLA-Cw*1601. The HLA-Cw*1601 allele was found to be expressed by 7 out of 99 individuals from a Caucasian population. Our results extend the range of tumor patients who could be eligible for immunization against MAGE antigens.


Asunto(s)
Antígenos de Neoplasias/inmunología , Epítopos/inmunología , Antígenos HLA-C/inmunología , Melanoma/inmunología , Proteínas de Neoplasias , Linfocitos T Citotóxicos/inmunología , Secuencia de Aminoácidos , Secuencia de Bases , Exodesoxirribonucleasas , Biblioteca Genómica , Antígenos HLA-C/genética , Humanos , Antígenos Específicos del Melanoma , Datos de Secuencia Molecular , Péptidos/inmunología , Receptores de Antígenos de Linfocitos T alfa-beta , Transfección , Factor de Necrosis Tumoral alfa/biosíntesis
10.
Int J Cancer ; 50(2): 289-97, 1992 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-1730522

RESUMEN

Limiting numbers of peripheral-blood mononuclear cells (PBMC) from melanoma patients were stimulated with irradiated autologous tumor cells in the presence of interleukins-2 and -4 and in the absence of feeder cells. The responder cells were restimulated every week. After 2 to 4 weeks, the microcultures were tested for their lytic activity against the autologous tumor cells. Significant lysis of the tumor cells was observed with a fraction of these microcultures, whereas no lysis was observed with control microcultures seeded without stimulator melanoma cells. Because our aim was to measure the precursor frequency of CTL showing specificity for the tumor, and not that of NK-like effectors that were also capable of lysing the melanoma cells, we used cold-target inhibition with an excess of NK target K562 to inhibit the NK-like activity. Microcultures whose lysis on the tumor cells was not abolished by K562 competition were observed. The specificity of these CTL clones was confirmed by the absence of lytic activity on autologous T-cell blasts. The numbers of microcultures with anti-tumor CTL activity fitted the zero-order of the Poisson distribution equation, indicating that they resulted from the activity of single T-cell clones. The frequency of anti-tumor CTL precursor cells (CTL-P) of 7 melanoma patients ranged from 1/900 to 1/33,000. Frequencies of anti-tumoral CTL-P were higher and NK-like effectors were less frequent when sorted CD8+ T lymphocytes were used as responder cells.


Asunto(s)
Melanoma/sangre , Linfocitos T Citotóxicos/inmunología , Relación CD4-CD8 , Citotoxicidad Inmunológica/fisiología , Células Madre Hematopoyéticas/fisiología , Humanos , Interleucina-2/farmacología , Células Asesinas Naturales/fisiología , Melanoma/inmunología , Subgrupos de Linfocitos T/inmunología , Linfocitos T Citotóxicos/fisiología , Células Tumorales Cultivadas
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