Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 45
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Int J Fertil Steril ; 10(1): 1-10, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27123194

RESUMO

Immune infertility, in terms of reproductive failure, has become a serious health issue involving approximately 1 out of 5 couples at reproductive age. Semen that is defined as a complex fluid containing sperm, cellular vesicles and other cells and components, could sensitize the female genital tract. The immune rejection of male semen in the female reproductive tract is explained as the failure of natural tolerance leading to local and/or systemic immune response. Present active immune mechanism may induce high levels of anti-seminal/sperm antibodies. It has already been proven that iso-immunization is associated with infertility. Comprehensive studies with regards to the identification of antibody-targets and the determination of specific antibody class contribute to the development of effective immuno-therapy and, on the other hand, potential immuno-contraception, and then of course to complex patient diagnosis. This review summarizes the aspects of female immune infertility.

2.
ScientificWorldJournal ; 2015: 940243, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26819967

RESUMO

This review summarizes the available data related to the effects of air pollution on pollen grains from different plant species. Several studies carried out either on in situ harvested pollen or on pollen exposed in different places more or less polluted are presented and discussed. The different experimental procedures used to monitor the impact of pollution on pollen grains and on various produced external or internal subparticles are listed. Physicochemical and biological effects of artificial pollution (gaseous and particulate) on pollen from different plants, in different laboratory conditions, are considered. The effects of polluted pollen grains, subparticles, and derived aeroallergens in animal models, in in vitro cell culture, on healthy human and allergic patients are described. Combined effects of atmospheric pollutants and pollen grains-derived biological material on allergic population are specifically discussed. Within the notion of "polluen," some methodological biases are underlined and research tracks in this field are proposed.


Assuntos
Poluição do Ar/efeitos adversos , Pólen/efeitos adversos , Rinite Alérgica Sazonal/imunologia , Animais , Humanos , Pólen/imunologia , Rinite Alérgica Sazonal/epidemiologia , Rinite Alérgica Sazonal/etiologia
3.
Pan Afr Med J ; 19: 284, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25870739

RESUMO

INTRODUCTION: Maize and rice are two crops constituting the main food supply in many under-developed and developing countries. Despite the large area devoted to the culture, the sensitization to the pollen from these plants is reported to be low and often considered as an occupational allergy. METHODS: Sixty five Malagasy pollen allergic patients were clinically and immunochemically investigated with regard to maize and rice pollen allergens. Pollen extracts were electrophoretically separated in 1 and 2 dimensions and IgE and IgG reactivities detected upon immunoblotting. RESULTS: When exploring the sensitization profile of Malagasy allergic patients to maize and rice pollen, it appears that a high proportion of these patients consulting during grass pollinating season were sensitized to both pollen as revealed by skin prick testing (62 vs. 59%) and IgE immunoblotting (85 vs. 40%). Several clinically relevant allergens were recognized by patients' serum IgE in maize and rice pollen extracts. CONCLUSION: The high levels of maize and rice pollen sensitization should be related, in this tropical region, to a specific environmental exposure including i) a proximity of the population to the allergenic sources and ii) a putative exacerbating effect of a highly polluted urban atmosphere on pollen allergenicity. Cross-reactivities between wild and cultivated grasses and also between rice and maize pollen are involved as well as some specific maize sensitizations. The presence of dense urban and peri-urban agriculture, in various African regions and worldwide, could be a high environmental risk factor for people sensitive to maize pollen.


Assuntos
Imunoglobulina E/imunologia , Oryza/imunologia , Pólen/imunologia , Zea mays/imunologia , Adolescente , Adulto , Idoso , Alérgenos/imunologia , Criança , Pré-Escolar , Feminino , Humanos , Immunoblotting/métodos , Imunoglobulina G/imunologia , Madagáscar , Masculino , Pessoa de Meia-Idade , Testes Cutâneos/métodos , Adulto Jovem
4.
J Chromatogr A ; 1267: 231-8, 2012 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-22883161

RESUMO

Capillary zone electrophoresis (CZE) in classical buffer-based background electrolytes (BGEs) and carrier ampholytes-based capillary electrophoresis (CABCE) using narrow pH cuts of carrier ampholytes (CA) as constituents of quasi-isoelectric BGEs have been applied to separation and characterization of synthetic human and salmon gonadotropin-releasing hormones (GnRH) and their derivatives and fragments. The selectivity, separation efficiency, resolution and speed of CZE and CABCE analyses have been compared within a wide pH range of the BGEs (3.50-9.75) using two mixtures of structurally related GnRH peptides as model analytes. A baseline separation of mixture 1 (human GnRH and its three fragments) was achieved in CA-based BGEs at pH 3.5 and in both classical and CA-based BGEs within the pH range 7.00-9.75. Full separation of mixture 2 (salmon GnRH, its two fragments and human GnRH fragment) was obtained in both types of BGEs at acidic pH values 3.5 and 4.00 and at neutral pH 7.00. In addition to the separation of related GnRHs, their effective electrophoretic mobilities were determined and from the dependences of mobilities on pH, the isoelectric points (pI) of analyzed peptides were estimated. The pI values obtained by CABCE were in a good agreement with those determined by CZE in classical BGEs but in some cases rather different from those predicted by theoretical calculations.


Assuntos
Eletroforese Capilar/métodos , Hormônio Liberador de Gonadotropina/química , Misturas Anfolíticas/química , Eletrólitos/química , Eletroforese Capilar/instrumentação , Hormônio Liberador de Gonadotropina/isolamento & purificação , Humanos
5.
Electrophoresis ; 33(3): 462-9, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22287175

RESUMO

Italian cypress (Cupressus sempervirens, Cups) pollen causes allergic diseases in inhabitants of many of the cities surrounding the Mediterranean basin. However, allergens of Cups pollen are still poorly known. We introduce here a novel proteomic approach based on double one-dimensional gel electrophoresis (D1-DE) as an alternative to the 2-DE immunoblot, for the specific IgE screening of allergenic proteins from pollen extracts. The sequential one-dimensional combination of IEF and SDS-PAGE associated with IgE immunoblotting allows a versatile multiplexed immunochemical analysis of selected groups of allergens by converting a single protein spot into an extended protein band. Moreover, the method appears to be valuable for MS/MS identification, without protein purification, of a new Cups pollen allergen at 43 kDa. D1-DE immunoblotting revealed that the prevalence of IgE sensitization to this allergen belonging to the polygalacturonase (PG) family was 70% in tested French allergic patients. In subsequent triple one-dimensional gel electrophoresis, the Cups pollen PG was shown to promote lectin-based protein-protein interactions. Therefore, D1-DE could be used in routine work as a convenient alternative to 2-DE immunoblotting for the simultaneous screening of allergenic components under identical experimental conditions, thereby saving considerable amounts of sera and allergen extracts.


Assuntos
Alérgenos/análise , Cupressus/química , Eletroforese em Gel de Poliacrilamida/métodos , Immunoblotting/métodos , Pólen/química , Alérgenos/química , Alérgenos/imunologia , Eletroforese em Gel Bidimensional , Humanos , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Focalização Isoelétrica , Pólen/imunologia , Proteômica/métodos , Rinite Alérgica Sazonal , Espectrometria de Massas em Tandem
6.
Proc Natl Acad Sci U S A ; 108(47): 18995-9000, 2011 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-22065791

RESUMO

Immune suppressive activities exerted by regulatory T-cell subsets have several specific functions, including self-tolerance and regulation of adaptive immune reactions, and their dysfunction can lead to autoimmune diseases and contribute to AIDS and cancer. Two functionally distinct regulatory T-cell subsets are currently identified in peripheral tissues: thymus-developed natural T regulatory cells (nTregs) controlling self-tolerance and antiinflammatory IL-10-secreting type 1 regulatory T cells (Tr1) derived from Ag-stimulated T cells, which regulate inflammation-dependent adaptive immunity and minimize immunopathology. We establish herein that cell contact-mediated nTreg regulatory function is inhibited by inflammation, especially in the presence of the complement C3b receptor (CD46). Instead, as with other T-cell subsets, the latter inflammatory conditions of stimulation skew nTreg differentiation to Tr1 cells secreting IL-10, an effect potentiated by IFN-α. The clinical relevance of these findings was verified in a study of 152 lupus patients, in which we showed that lupus nTreg dysfunction is not due to intrinsic defects but is rather induced by C3b stimulation of CD46 and IFN-α and that these immune components of inflammation are directly associated with active lupus. These results provide a rationale for using anti-IFN-α Ab immunotherapy in lupus patients.


Assuntos
Diferenciação Celular/imunologia , Ativação do Complemento/imunologia , Imunoterapia/métodos , Interferon-alfa/metabolismo , Lúpus Eritematoso Sistêmico/imunologia , Proteína Cofatora de Membrana/metabolismo , Linfócitos T Reguladores/imunologia , Anticorpos Monoclonais , Complemento C3b/imunologia , Primers do DNA/genética , Citometria de Fluxo , Humanos , Interferon-alfa/imunologia , Interleucina-10/imunologia , Leucócitos Mononucleares , Modelos Lineares , Proteína Cofatora de Membrana/imunologia , Reação em Cadeia da Polimerase em Tempo Real
7.
Int Arch Allergy Immunol ; 154(2): 128-36, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-20733321

RESUMO

BACKGROUND: Grass pollen is one of the most important aeroallergens in Europe. It highly contributes to respiratory allergic diseases, mainly allergic rhinitis. In contact to water or airborne pollutants, pollen grains can release pollen cytoplasmic granules (PCGs) containing allergens. Because of their size (<5 µm), PCGs may penetrate deeper into the lungs to induce higher allergic responses, such as asthma. They have been associated with thunderstorm-related asthma. The aim of this study was to evaluate, with Brown Norway rats, the allergenic potential of isolated PCGs and to compare it with the allergenicity of whole timothy grass pollen. METHODS: Rats were sensitized (day 0) and challenged (day 21), in controlled comparative conditions, with pollen grains (0.5 mg) or PCGs (4.5 × 107 and 0.5 mg). At day 25, blood samples, bronchoalveolar lavage fluid (BALF) and bronchial lymph node were collected. IgE and IgG1 levels in sera were assessed by ELISA. Alveolar cells, protein and cytokine concentrations were quantified in BALF. T cell proliferation, in response to pollen or granules, was performed by lymph node assay. RESULTS: The results showed that proliferative responses of lymph node cells were similar in PCG- and pollen-sensitized rats. IgE and IgG1 levels were higher in pollen- than in PCG-sensitized rats. However, eosinophils, lymphocytes and pro-allergy cytokines in BALF were higher in PCG- than in pollen-sensitized rats. CONCLUSIONS: Thus, PCGs, able to deeply penetrate in the respiratory tract, induced local and strong allergic and inflammatory responses more linked with asthma- than rhinitis-related allergic symptoms.


Assuntos
Grânulos Citoplasmáticos/imunologia , Pólen/imunologia , Hipersensibilidade Respiratória/imunologia , Animais , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Citocinas/imunologia , Modelos Animais de Doenças , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Masculino , Distribuição Aleatória , Ratos , Estatísticas não Paramétricas
8.
Lab Chip ; 10(19): 2597-604, 2010 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-20714504

RESUMO

In this paper, we demonstrate the possibility to use a micropillar array to perform molecular immunodiagnosis. A polydimethylsiloxane (PDMS) microdevice consisting of a rectangular array of micropillars (45 µm in height, 100 × 100 µm square cross section) was used to replace microchannels or gels (polyacrylamide or agarose) to perform electrokinetic separation. This microarray was used to mimic highly diluted gel and to maintain electrolyte within the pillar zone by capillary effect. The electrolyte composition (glycerol and agarose content) was investigated in order to improve protein separation by isoelectric focusing (IEF). The influence of glycerol on focusing time and on the different evaporative contributions was further evaluated. In order to perform an immunodiagnostic of milk allergy, different surface treatments were optimized to prevent milk allergen adsorption on PDMS surface. Poly(dimethylacrylamide)-co-allyl glycidyl ether (PDMA-AGE) as well as gelatin led to a satisfactory signal to noise ratio. Finally the possibility to perform protein mixture separation using this micropillar array chip followed by immunoblotting was demonstrated by using the serum from an allergic individual, confirming the great potential of this analytical platform in the field of immunodiagnosis.


Assuntos
Colorimetria/instrumentação , Imunoensaio/instrumentação , Análise em Microsséries/instrumentação , Técnicas Analíticas Microfluídicas/instrumentação , Kit de Reagentes para Diagnóstico , Desenho de Equipamento , Análise de Falha de Equipamento
9.
J Proteomics ; 73(7): 1368-80, 2010 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-20226888

RESUMO

The proteome of Hevea brasiliensis latex has been explored in depth via combinatorial peptide ligand libraries. A total of 300 unique gene products have been identified in this latex, whose proteome has been largely unknown up to the present. In search for unknown allergens, control latex and eluates from the ligand libraries have been fractionated by two-dimensional mapping, blotted and confronted with sera of 18 patients. In addition to the already known and named Hevea major allergens, we have unambiguously detected several others like, for instance: heat shock protein (81 kDa), proteasome subunit (30 kDa), protease inhibitor (8 kDa), hevamine A (43 kDa) and glyceraldehyde-3-phosphate dehydrogenase (37 kDa). Gene Ontology analysis of analyzed fractions has shown that major functions are substantially unchanged after sample treatment, while novel biological functions appeared that were undetectable in the crude sample.


Assuntos
Antígenos de Plantas/química , Antígenos de Plantas/imunologia , Hevea/imunologia , Látex/imunologia , Biblioteca de Peptídeos , Proteoma/química , Proteoma/imunologia , Técnicas de Química Combinatória/métodos , Humanos , Hipersensibilidade ao Látex/imunologia
11.
World Allergy Organ J ; 3(8): 229-234, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23282715

RESUMO

BACKGROUND: : Cypress pollen is becoming an increasing cause of respiratory allergy in some regions worldwide. OBJECTIVE: : The aim of this study was to determine some of the main allergens implicated in the common cypress (C. sempervirens) pollen allergy. METHODS: : Pollen extracts were optimized by using some detergents and chaotropes in order to solubilize both water and non-water soluble proteins. C. sempervirens pollen extracts were resolved by one and two dimensional electrophoresis and assayed with sera of allergic subjects. RESULTS: : Five predominant allergens with apparent molecular masses ranging from 14 to 94 kDa were detected. Two principal IgE-binding patterns were clearly distinguishable: a first one represents patients with a heterogeneous IgE reactivity to several allergens (pI 3.5-8.5) with molecular masses ranging from 35 to 94 kDa (HMW). The second one corresponds to little less than 50 percent of tested patients with specific IgE binding to 2-3 spots (pI 10-11) of about 14 kDa and weak or no reactivity to HMW allergens. CONCLUSION: : The extraction of water insoluble proteins allows the revelation of novel allergens as well as different allergen sensitization patterns in the C. sempervirens pollen allergy. These novel IgE reactive components may subsequently be applied to expand the panel of well-defined cypress pollen molecules for a more efficient allergen-based diagnosis and therapy.

12.
Electrophoresis ; 30(24): 4256-63, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20013909

RESUMO

The use of glass and PDMS microchips has been investigated to perform rapid and efficient separation of allergenic whey proteins by IEF. To decrease EOF and to limit protein adsorption, two coating procedures have been compared. The first one consists in immobilizing hydroxypropyl cellulose (HPC) and the second one poly(dimethylacrylamide-co-allyl glycidyl ether) (PDMA-AGE). EOF limitation has been evaluated using frontal electrophoresis of a fluorescent marker of known effective mobility. EOF velocity was decreased by a factor about 100 and 30, respectively. pH gradient formation has been evaluated for each microchip using fluorescent pI markers. It was demonstrated that as expected a coating was essential to avoid pH gradient drift. Both coatings were efficient on glass microchips, but only PDMA-AGE allowed satisfying focusing of pI markers on PDMS microchips. Fluorescent covalent and noncovalent labelings of milk proteins have been compared by IEF on slab-gels. IEF separation of three major allergenic whey proteins [beta-lactoglobulin A (pI 5.25) and B (pI 5.35) and alpha-lactalbumin (pI 4.2-4.5)] was performed in both microchips. Milk proteins were separated with better resolution and shorter analysis time than by classical CIEF. Finally, better resolutions for milk allergens separation were obtained on glass microchips.


Assuntos
Alérgenos/análise , Focalização Isoelétrica/métodos , Dispositivos Lab-On-A-Chip , Proteínas do Leite/análise , Concentração de Íons de Hidrogênio
13.
J Proteome Res ; 8(8): 3925-36, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19499900

RESUMO

The use of combinatorial peptide ligand libraries, containing hexapeptides terminating with a primary amine, or modified with a terminal carboxyl group, allowed discovering and identifying a large number of previously unreported proteins in cow's whey. Whereas comprehensive whey protein lists progressively increased in the last 6 years from 17 unique gene products to more than 100, our findings have considerably expanded this list to a total of 149 unique protein species, of which 100 were not described in previous proteomics studies. As an additional interesting result, a polymorphic alkaline protein was observed with a strong positive signal when blotted from an isoelectric focusing separation in gel and tested with sera of allergic patients. This polymorphic protein, found only after treatment with the peptide library, was identified as an immunoglobulin (Ig), a minor allergen that had been largely amplified. The list of cow's whey components here reported is by far the most comprehensive at present and could serve as a starting point for the functional characterization of low-abundance proteins possibly having novel pharmaceutical, diagnostic, and biomedical applications.


Assuntos
Proteínas do Leite/análise , Leite/química , Proteômica/métodos , Alérgenos/análise , Animais , Bovinos , Cromatografia Líquida , Análise por Conglomerados , Técnicas de Química Combinatória/métodos , Bases de Dados de Proteínas , Eletroforese em Gel Bidimensional , Immunoblotting , Biblioteca de Peptídeos , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem , Proteínas do Soro do Leite
14.
Proc Natl Acad Sci U S A ; 106(13): 5294-9, 2009 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-19279210

RESUMO

A major involvement of IFNalpha in the etiopathogenesis of systemic lupus erythematosus has been suggested by clinical observations, including the increase of serum levels of this cytokine in patients with active disease. Supporting this hypothesis, we have shown that expression of IFNalpha from a recombinant adenovirus (IFNalpha Adv) precipitates lupus manifestations in genetically susceptible New Zealand Black (NZB) x New Zealand White (NZW)F(1) mice (NZB/W) but not in BALB/c mice. In the present investigation, we have prepared an IFNalpha immunogen, termed IFNalpha kinoid, which, appropriately adjuvanted, induces transient neutralizing antibodies (Abs) but no cellular immune response to the cytokine and without apparent side effects. Using this preparation, we also showed that, in kinoid-vaccinated NZB/W mice, lupus manifestations, including proteinuria, histological renal lesions, and death triggered by IFNalpha Adv challenge were delayed/prevented as long as an effective threshold of anti-IFNalpha inhibitory capacity was present in the serum.


Assuntos
Formação de Anticorpos , Interferon-alfa/imunologia , Lúpus Eritematoso Sistêmico/terapia , Vacinas/uso terapêutico , Animais , Anticorpos , Morte , Modelos Animais de Doenças , Nefropatias , Camundongos , Camundongos Endogâmicos , Proteinúria , Especificidade da Espécie , Resultado do Tratamento , Vacinas/imunologia
15.
Mol Immunol ; 46(6): 1058-66, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18992943

RESUMO

In milk, kappa-, beta-, alphas(1)- and alphas(2)-casein (CN) are associated into a supramolecular assembly, the micelle. In this work, CN micelles contained in fresh skim milk were used to produce over 100 monoclonal antibodies. The specificity of these probes was determined using libraries of synthetic peptides and peptides fractionated from tryptic hydrolysis of purified CNs. Although kappa-CN and alphas(2)-CN are minor proteins in the micelle (ratio 1:1:4:4 for kappa, alphas(2), alphas(1), beta) a proportionally high number of clones were produced towards these two proteins (32 for each), compared to 9 and 29 for alphas(1)-CN and beta-CN, respectively. Most of the beta-CN and kappa-CN epitopes were identified, while about 50% of alphas(1)-CN and alphas(2)-CN antibodies were suspected to react to conformational linear or discontinuous epitopes, since no peptide binding could be identified. Antibody binding to the phosphoserine rich regions of the three calcium sensitive CNs was weak or non-existing, suggesting them to be hidden in the micelle structure together with alphas(1)-CN. The C-terminal glycomacropeptide of kappa-CN and the C-terminal moiety of beta-CN were well exposed generating the majority of the antibodies specific for these two proteins. The two major antigenic sites of alphas(2) were alphas(2)-CN (f96-114) and (f16-35). Cross-reaction between alphas(2)-CN specific antibodies with alphas(1)-CN illustrated the tangled structure between the two proteins. Immuno-dominant epitopes identified in the present study totally differ from those known for the purified caseins suggesting they were specific for the micelle supramolecular structure.


Assuntos
Anticorpos Monoclonais/imunologia , Caseínas/imunologia , Epitopos/imunologia , Leite/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/biossíntese , Bovinos , Reações Cruzadas , Mapeamento de Epitopos/métodos , Feminino , Camundongos , Micelas , Dados de Sequência Molecular , Peptídeos/imunologia , Multimerização Proteica
16.
World Allergy Organ J ; 2(9): 201-7, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23283149

RESUMO

BACKGROUND: : Grass pollen is one of the most important aeroallergen vectors in Europe. Under some meteorological factors, pollen grains can release pollen cytoplasmic granules (PCGs). PCGs induce allergic responses. Several studies have shown that during a period of thunderstorms the number of patients with asthma increases because of higher airborne concentrations of PCGs. OBJECTIVE: : The aims of the study were to assess the allergenicity of interactive effects between pollen and PCGs and to compare it with allergenicity of Timothy grass pollen and PCGs in Brown Norway rats. METHODS: : Rats were sensitized (day 0) and challenged (day 21) with pollen grains and/or PCGs. Four groups were studied: pollen-pollen (PP), PCGs-PCGs (GG), pollen-PCGs (PG), and PCGs-pollen (GP). Blood samples, bronchoalveolar lavage fluid, and bronchial lymph node were collected at day 25. IgE and IgG1 levels in sera were assessed by enzyme-linked immunosorbent assay. Alveolar cells, protein, and cytokine concentrations were quantified in bronchoalveolar lavage fluid. T-cell proliferation, in response to pollen or granules, was performed by lymph node assay. RESULTS: : Interactive effects between pollen and PCGs increased IgE and IgG1 levels when compared with those of the negative control. These increases were lower than those of the PP group but similar to the levels obtained by the GG group. Whatever was used in the sensitization and/or challenge phase, PCGs increased lymphocyte and Rantes levels compared with those of the pollen group. The interactive effects increased IL-1α and IL-1ß compared with those of the PP and GG groups. CONCLUSIONS: : Immunologic interactive effects have been shown between pollen and PCGs. For humoral and cellular allergic responses, interactive effects between the 2 aeroallergenic sources used in this study seem to be influenced mainly by PCGs.

17.
Anal Chem ; 80(24): 9583-8, 2008 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-18991389

RESUMO

A magnetic beads based immunoaffinity capillary electrophoresis method for total Immunoglobulin E quantification in serum has been developed. The method combines speed, automation ability, and minimal sample consumption. Only 1 microL of serum is required while the whole immunoaffinity capillary electrophoresis method is performed in less than 50 min. The concomitant use of online immunocapture, transient isotachophoresis, and laser-induced fluorescence detection provides a sensitivity in the low picomolar range and a highly linear fluorescence response over 4 orders of magnitude (IgE concentration ranging from 2.4 to 2400 ng/mL). After validation with a reference material, the method has been successfully applied to the quantification of total IgEs in patient sera. The results compared well with classical ImmunoCap data.


Assuntos
Eletroforese Capilar , Imunoensaio/métodos , Imunoglobulina E/sangue , Lasers , Magnetismo , Cromatografia de Afinidade , Estudos de Viabilidade , Fluorescência , Humanos
18.
Electrophoresis ; 29(18): 3759-67, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18850645

RESUMO

Carrier ampholyte-based capillary electrophoresis (CABCE) has recently been introduced as an alternative to CE (CZE) in the classical buffers. In this study, isoelectric BGEs were obtained by fractionation of Servalyt pH 4-9 carrier ampholytes to cuts of typical width of 0.2 pH unit. CABCE feasibility was examined on a series of insect oostatic peptides, i.e. proline-rich di- to decapeptides, and phosphinic pseudopeptides--tetrapeptide mimetics synthesized as a mixture of four diastereomers having the -P(O)(OH)-CH(2)- moiety embedded into the peptide backbone. With identical selectivity, the separation efficiency of CABCE proved to be as good as classical CE for the insect oostatic peptides and better for diastereomers of the phosphinic pseudopeptides. In addition, despite the numerous species present in the narrow pH cuts of carrier ampholytes, CABCE seems to be free of system zones that could hamper the analysis. Peak symmetry was good for moderately to low mobile peptides, whereas some peak distortion due to electromigration dispersion, was observed for short peptides of rather high mobility.


Assuntos
Misturas Anfolíticas/química , Eletroforese Capilar/métodos , Peptídeos/isolamento & purificação , Concentração de Íons de Hidrogênio , Peptídeos/análise , Ácidos Fosfínicos/química
19.
Electrophoresis ; 29(15): 3164-7, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18618459

RESUMO

The use of quasi-isoelectric buffers consisting of narrow pH cuts of carrier ampholytes (NC) has been investigated to limit protein adsorption on capillary walls during capillary zone electrophoresis experiments. To quantify protein adsorption on the silica surface, a method derived from that of Towns and Regnier has been developed. alpha-Lactalbumin (14 kDa, pI 4.8) and alpha-chymotrypsinogen A (25 kDa, pI 9.2) have been used as model proteins. Acidic narrow pH cuts of carrier ampholytes (NC, pH 3.0) obtained from fractionation of Serva 4-9 carrier ampholytes were used as BGE in bare-silica capillaries, and allowed to decrease significantly protein adsorption, as compared to experiments performed with classical formate buffer. The use of NC as BGE appeared to be as efficient as the use of polydimethylacrylamide coating to prevent protein adsorption. This increase of protein recovery when using NC was attributed to the interaction of carrier ampholytes with the silica surface, leading to a shielding of the capillary wall.


Assuntos
Eletroforese Capilar/métodos , Proteínas/química , Acrilamidas , Adsorção , Misturas Anfolíticas , Animais , Soluções Tampão , Quimotripsinogênio/análise , Quimotripsinogênio/química , Ponto Isoelétrico , Lactalbumina/análise , Lactalbumina/química , Proteínas/análise , Dióxido de Silício
20.
Electrophoresis ; 29(16): 3414-21, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18651703

RESUMO

Protein A-coated magnetic beads (0.3 mum) have been trapped in a small portion of a neutrally coated capillary (50 mum id). Anti-beta-lactoglobulin (beta-LG) antibodies have then been immobilized on the beads through strong affinity with protein A to subsequently capture beta-LG from model or real samples. Once the immunocomplexes formed at physiological pH, a discontinuous buffer system has been used to release the partners and preconcentrate them by transient ITP. The antigens and antibodies have finally been separated by CZE and detected by UV absorbance. An LOQ of 55 nM has been achieved. This methodology has been applied to quantify native beta-LG in pasteurized and ultra-high-temperature-treated bovine milk. All the described procedures, including immunosorbent preparation, sample extraction, cleanup, preconcentration, and separation are completely automated on a commercial CE instrument. As this CE immunoassay method is simple, rapid, selective, and sensitive, it should be a practical and attractive technology for the analysis of complicated biological samples.


Assuntos
Anticorpos/imunologia , Lactoglobulinas/imunologia , Eletroforese Capilar/métodos , Imunoensaio , Separação Imunomagnética/métodos , Lactoglobulinas/análise , Proteína Estafilocócica A/imunologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...