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1.
J Immunol Methods ; 522: 113557, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37689389

RESUMEN

Polybia paulista is a neotropical social wasp related to severe accidents and allergic reactions cases, including anaphylaxis, in southeastern Brazil. Antigen 5 (Poly p 5) is a major allergenic protein from its venom with potential use for component-resolved diagnostic. Therefore, the previous characterization of the immune response profile triggered by Poly p 5 should be evaluated. Recombinant Poly p 5 (rPoly p 5) was used to sensitize BALB/c mice with six weekly intradermal doses, and the specific antibody production and the functional profile of CD4+ T cells were assessed. rPoly p 5 induced the production of specific immunoglobulins (sIg) sIgE, sIgG1 and sIgG2a, which could recognize natural Poly p 5 presented in the venom of four different wasp species. rPoly p 5 stimulated in vitro the CD4+ T cells from immunized mice, which showed a significant proliferative response. These antigen-specific CD4+T cells produced IFN-γ and IL-17A cytokines and increased ROR-γT transcription factor expression. No differences between the control group and sensitized mice were found in IL-4 production and GATA-3 and T-bet expression. Interestingly, increased CD25+FoxP3+ regulatory T cells (Tregs) frequency was observed in the splenocyte cell cultures from rPoly p 5 immunized mice after the in vitro stimulation with both P. paulista venom extract and rPoly p 5. Here we showed that rPoly p 5 induces antigen-specific antibodies capable of recognizing Antigen 5 in the venom of four wasp species and modulates antigen-specific CD4+ T cells to IFN-γ production response associated with a Th17 profile in sensitized mice. These findings emphasize the potential use of rPoly p 5 as an essential source of a major wasp allergen with significant immunological properties.


Asunto(s)
Anafilaxia , Avispas , Animales , Ratones , Avispas/metabolismo , Venenos de Avispas/metabolismo , Formación de Anticuerpos , Alérgenos , Linfocitos T CD4-Positivos
2.
Toxins (Basel) ; 12(6)2020 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-32521656

RESUMEN

Insect venom can cause systemic allergic reactions, including anaphylaxis. Improvements in diagnosis and venom immunotherapy (VIT) are based on a better understanding of an immunological response triggered by venom allergens. Previously, we demonstrated that the recombinant phospholipase A1 (rPoly p 1) from Polybia paulista wasp venom induces specific IgE and IgG antibodies in sensitized mice, which recognized the native allergen. Here, we addressed the T cell immune response of rPoly p 1-sensitized BALB/c mice. Cultures of splenocytes were stimulated with Polybia paulista venom extract and the proliferation of CD8+ and CD4+ T cells and the frequency of T regulatory cells (Tregs) populations were assessed by flow cytometry. Cytokines were quantified in cell culture supernatants in ELISA assays. The in vitro stimulation of T cells from sensitized mice induces a significant proliferation of CD4+ T cells, but not of CD8+ T cells. The cytokine pattern showed a high concentration of IFN-γ and IL-6, and no significant differences to IL-4, IL-1ß and TGF-ß1 production. In addition, the rPoly p 1 group showed a pronounced expansion of CD4+CD25+FoxP3+ and CD4+CD25-FoxP3+ Tregs. rPoly p 1 sensitization induces a Th1/Treg profile in CD4+ T cell subset, suggesting its potential use in wasp venom immunotherapy.


Asunto(s)
Alérgenos/farmacología , Linfocitos T CD4-Positivos/efectos de los fármacos , Desensibilización Inmunológica , Proteínas de Insectos/farmacología , Fosfolipasas A1/farmacología , Venenos de Avispas/farmacología , Alérgenos/inmunología , Animales , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Citocinas/metabolismo , Femenino , Hipersensibilidad/inmunología , Hipersensibilidad/metabolismo , Hipersensibilidad/terapia , Mordeduras y Picaduras de Insectos/inmunología , Mordeduras y Picaduras de Insectos/metabolismo , Mordeduras y Picaduras de Insectos/terapia , Proteínas de Insectos/inmunología , Activación de Linfocitos/efectos de los fármacos , Ratones Endogámicos BALB C , Fosfolipasas A1/inmunología , Venenos de Avispas/inmunología
3.
3 Biotech ; 10(5): 217, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32355591

RESUMEN

Phospholipase A1 (PLA1) is one of the three major allergens identified in the venom of P. paulista (Hymenoptera: Vespidae), a clinically relevant wasp from southeastern Brazil. The recombinant form of this allergen (rPoly p 1) could be used for the development of molecular diagnostic of venom allergy. Early attempts to produce rPoly p 1 using Escherichia coli BL21 (DE3) cells rendered high yields of the insoluble rPoly p 1 but with low levels of solubilized protein recovery (12%). Here, we aimed to improve the production of rPoly p 1 in E. coli by testing different conditions of expression, solubilization of the inclusion bodies and protein purification. The results showed that the expression at 16 °C and 0.1 mM of IPTG increased the production of rPoly p 1, still in the insoluble form, but with high solubilized protein yields after incubation with citrate-phosphate buffer with 0.15 M NaCl, 6 M urea, pH 2.6 at 25 ºC for 2 h. The venom allergen was also cloned in pPICZαA vector for soluble expression as a secreted protein in Pichia pastoris X-33 cells, rendering almost undetectable levels (nanograms) in the culture supernatant. In contrast, a sevenfold increase of the solubilized and purified rPoly p 1 yields (1.5 g/L of fermentation broth) was obtained after improved production in E. coli. The identity of the protein was confirmed with an anti-His antibody and MS spectra. Allergen-specific IgE (sIgE)-mediated recognition was evaluated in immunoblotting with sera of allergic patients (n = 40). Moreover, rPoly p 1 showed high levels of diagnostic sensitivity (95%). The optimized strategy for rPoly p 1 production described here, will provide the amounts of allergen necessary for the subsequent protein refolding, immunological characterization steps, and ultimately, to the development of molecular diagnostic for P. paulista venom allergy.

4.
Toxins (Basel) ; 10(8)2018 07 24.
Artículo en Inglés | MEDLINE | ID: mdl-30042313

RESUMEN

Although systemic reactions caused by allergenic proteins present in venoms affect a small part of the world population, Hymenoptera stings are among the main causes of immediate hypersensitivity responses, with risk of anaphylactic shock. In the attempt to obtain therapeutic treatments and prophylaxis to hypersensitivity responses, interest in the molecular characterization of these allergens has grown in the scientific community due to the promising results obtained in immunological and clinical studies. The present review provides an update on the knowledge regarding the immune response and the therapeutic potential of Antigen 5 derived from Hymenoptera venom. The results confirm that the identification and topology of epitopes, associated with molecular regions that interact with antibodies, are crucial to the improvement of hypersensitivity diagnostic methods.


Asunto(s)
Alérgenos/inmunología , Venenos de Avispas/inmunología , Animales , Humanos , Hipersensibilidad/terapia , Mordeduras y Picaduras de Insectos/complicaciones , Mordeduras y Picaduras de Insectos/terapia
5.
Mol Immunol ; 93: 87-93, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29156294

RESUMEN

Molecular cross-reactivity caused by allergen homology or cross-reactive carbohydrate determinants (CCDs) is a major challenge for diagnosis and immunotherapy of insect venom allergy. Venom phospholipases A1 (PLA1s) are classical, mostly non-glycosylated wasp and ant allergens that provide diagnostic benefit for differentiation of genuine sensitizations from cross-reactivity. As CCD-free molecules, venom PLA1s are not causative for CCD-based cross-reactivity. Little is known however about the protein-based cross-reactivity of PLA1 within vespid species. Here, we address PLA1-based cross-reactivity among ten clinically relevant Hymenoptera venoms from Neotropical and temperate regions including Polybia paulista (paulistinha) venom and Vespula vulgaris (yellow jacket) venom. In order to evaluate cross-reactivity, sera of mice sensitized with recombinant PLA1 (rPoly p 1) from P. paulista wasp venom were used. Pronounced IgE and IgG based cross-reactivity was detected for wasp venoms regardless the geographical region of origin. The cross-reactivity correlated well with the identity of the primary sequence and 3-D models of PLA1 proteins. In contrast, these mice sera showed no reaction with honeybee (HBV) and fire ant venom. Furthermore, sera from patients monosensitized to HBV and fire ants did not recognize the rPoly p 1 in immunoblotting. Our findings reveal the presence of conserved epitopes in the PLA1s from several clinically relevant wasps as major cause of PLA1-based in vitro cross-reactivity. These findings emphasize the limitations but also the potential of PLA1-based HVA diagnostics.


Asunto(s)
Venenos de Hormiga/inmunología , Venenos de Abeja/inmunología , Hipersensibilidad/inmunología , Proteínas de Insectos/inmunología , Fosfolipasas A1/inmunología , Venenos de Avispas/inmunología , Alérgenos/inmunología , Animales , Hormigas/enzimología , Hormigas/inmunología , Abejas/enzimología , Abejas/inmunología , Brasil , Reacciones Cruzadas , Europa (Continente) , Femenino , Humanos , Hipersensibilidad/sangre , Hipersensibilidad/etiología , Inmunoglobulina E/sangre , Inmunoglobulina E/inmunología , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Pruebas Intradérmicas , Ratones , Ratones Endogámicos BALB C , Modelos Moleculares , Conformación Proteica , Proteínas Recombinantes/inmunología , Avispas/enzimología , Avispas/inmunología
6.
Toxins (Basel) ; 9(9)2017 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-28837089

RESUMEN

Polybia paulista (Hymenoptera: Vespidae) is responsible for a high number of sting accidents and anaphylaxis events in Southeast Brazil, Argentina and Paraguay. The specific detection of allergy to the venom of this wasp is often hampered by the lack of recombinant allergens currently available for molecular diagnosis. Antigen 5 (~23 kDa) from P. paulista venom (Poly p 5) is a highly abundant and glycosylated allergenic protein that could be used for development of component-resolved diagnosis (CRD). Here, we describe the cloning and heterologous expression of the antigen 5 (rPoly p 5) from P. paulista venom using the eukaryotic system Pichia pastoris. The expression as a secreted protein yielded high levels of soluble rPoly p 5. The recombinant allergen was further purified to homogeneity (99%) using a two-step chromatographic procedure. Simultaneously, the native form of the allergen (nPoly p 5) was purified from the wasp venom by Ion exchange chromatography. The rPoly p 5 and nPoly p 5 were then submitted to a comparative analysis of IgE-mediated immunodetection using sera from patients previously diagnosed with sensitization to wasp venoms. Both rPoly p 5 and nPoly p 5 were recognized by specific IgE (sIgE) in the sera of the allergic individuals. The high levels of identity found between nPoly p 5 and rPoly p 5 by the alignment of its primary sequences as well as by 3-D models support the results obtained in the immunoblot. Overall, we showed that P. pastoris is a suitable system for production of soluble rPoly p 5 and that the recombinant allergen represents a potential candidate for molecular diagnosis of P.paulista venom allergy.


Asunto(s)
Alérgenos , Venenos de Avispas/química , Alérgenos/química , Alérgenos/genética , Alérgenos/inmunología , Alérgenos/aislamiento & purificación , Humanos , Hipersensibilidad/diagnóstico , Inmunoglobulina E/sangre , Inmunoglobulina E/inmunología , Modelos Moleculares , Pichia/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/aislamiento & purificación , Venenos de Avispas/genética , Venenos de Avispas/inmunología , Venenos de Avispas/aislamiento & purificación
7.
Toxins (Basel) ; 7(7): 2551-70, 2015 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-26184309

RESUMEN

Along with food and drug allergic reactions, a Hymenoptera insect Sting (Apoidea, Vespidae, Formicidae) is one of the most common causes of anaphylaxis worldwide. Diagnoses of Hymenoptera venom allergy (HVA) and specific immunotherapy (SIT) have been based on the use of crude venom extracts. However, the incidence of cross-reactivity and low levels of sensibility during diagnosis, as well as the occurrence of nonspecific sensitization and undesired side effects during SIT, encourage the search for novel allergenic materials. Recombinant allergens are an interesting approach to improve allergy diagnosis and SIT because they circumvent major problems associated with the use of crude venom. Production of recombinant allergens depends on the profound molecular characterization of the natural counterpart by combining some "omics" approaches with high-throughput screening techniques and the selection of an appropriate system for heterologous expression. To date, several clinically relevant allergens and novel venom toxins have been identified, cloned and characterized, enabling a better understanding of the whole allergenic and envenoming processes. Here, we review recent findings on identification, molecular characterization and recombinant expression of Hymenoptera venom allergens and on the evaluation of these heterologous proteins as valuable tools for tackling remaining pitfalls on HVA diagnosis and immunotherapy.


Asunto(s)
Alérgenos/inmunología , Venenos de Artrópodos/inmunología , Himenópteros/inmunología , Hipersensibilidad/diagnóstico , Hipersensibilidad/terapia , Alérgenos/genética , Alérgenos/uso terapéutico , Animales , Venenos de Artrópodos/genética , Venenos de Artrópodos/uso terapéutico , Clonación Molecular , Desensibilización Inmunológica , Humanos , Himenópteros/metabolismo , Proteoma , Proteínas Recombinantes , Transcriptoma
8.
Toxicon ; 82: 104-11, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24593966

RESUMEN

To date, there are no allergenic extracts or components available in Brazil to diagnosis and treatment of patients with venom allergy from social wasp (Vespidae Family; Polistinae Subfamily) despite of the great number of existing species. We evaluated the immunogenic potential of the Hyal recombinant protein (Pp-Hyal-rec) which was expressed in an insoluble form in comparison with the allergenic native protein (Pp-Hyal-nat) for recognition of immunoglobulin E (IgE) in the serum of allergic patients to venom of the endemic social wasp Polybia paulista from São Paulo State, Brazil. Hyal cDNA from the venom of the social wasp P. paulista (Pp-Hyal) (GI: 302201582) was cloned into the expression vector pET-28a in Escherichia coli DE3 (BL21) cells. Solubilization and purification of Pp-Hyal-rec from inclusion bodies were performed using Ni(2+) affinity chromatography (Ni-NTA-Agarose) under denaturing conditions. Both the native (Pp-Hyal-nat) and the recombinant (Pp-Hyal-rec) purified allergens were used for Western blotting to assess the levels of Pp-Hyal-IgE specific in the serum of 10 patients exclusively reactive to the venom of the social wasp P. paulista. The immune sera specifically recognized the band corresponding to the Pp-Hyal-rec protein (40 kDa) at a higher intensity than the native allergen (39 kDa). The sera recognized other proteins in P. paulista crude venom extract to a lesser extent, likely corresponding to other venom allergens such as phospholipase (34 kDa), Antigen 5 (25 kDa), and proteases. The recognition pattern of the immune sera to the Pp-Hyal-rec allergen strongly suggests that this recombinant antigen could be used for developing a diagnostic allergy test as well as for specific immunotherapy (IT).


Asunto(s)
Alérgenos/genética , Alérgenos/inmunología , Hialuronoglucosaminidasa/inmunología , Inmunoglobulina E/inmunología , Venenos de Avispas/enzimología , Venenos de Avispas/inmunología , Avispas/inmunología , Animales , Especificidad de Anticuerpos , Clonación Molecular , Reacciones Cruzadas , Humanos , Hipersensibilidad/inmunología , Cuerpos de Inclusión/inmunología , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/inmunología , Venenos de Avispas/genética
9.
Toxicon ; 64: 70-80, 2013 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-23305623

RESUMEN

In this study, we describe the cDNA cloning, sequencing, and 3-D structure of the allergen hyaluronidase from Polybia paulista venom (Pp-Hyal). Using a proteomic approach, the native form of Pp-Hyal was purified to homogeneity and used to produce a Pp-specific polyclonal antibody. The results revealed that Pp-Hyal can be classified as a glycosyl hydrolase and that the full-length Pp-Hyal cDNA (1315 bp; GI: 302201582) is similar (80-90%) to hyaluronidase from the venoms of endemic Northern wasp species. The isolated mature protein is comprised of 338 amino acids, with a theoretical pI of 8.77 and a molecular mass of 39,648.8 Da versus a pI of 8.13 and 43,277.0 Da indicated by MS. The Pp-Hyal 3D-structural model revealed a central core (α/ß)(7) barrel, two sulfide bonds (Cys 19-308 and Cys 185-197), and three putative glycosylation sites (Asn79, Asn187, and Asn325), two of which are also found in the rVes v 2 protein. Based on the model, residues Ser299, Asp107, and Glu109 interact with the substrate and potential epitopes (five conformational and seven linear) located at surface-exposed regions of the structure. Purified native Pp-Hyal showed high similarity (97%) with hyaluronidase from Polistes annularis venom (Q9U6V9). Immunoblotting analysis confirmed the specificity of the Pp-Hyal-specific antibody as it recognized the Pp-Hyal protein in both the purified fraction and P. paulista crude venom. No reaction was observed with the venoms of Apis mellifera, Solenopsis invicta, Agelaia pallipes pallipes, and Polistes lanio lanio, with the exception of immune cross-reactivity with venoms of the genus Polybia (sericea and ignobilis). Our results demonstrate cross-reactivity only between wasp venoms from the genus Polybia. The absence of cross-reactivity between the venoms of wasps and bees observed here is important because it allows identification of the insect responsible for sensitization, or at least of the phylogenetically closest insect, in order to facilitate effective immunotherapy in allergic patients.


Asunto(s)
Clonación Molecular/métodos , Hialuronoglucosaminidasa/genética , Hialuronoglucosaminidasa/metabolismo , Venenos de Avispas/enzimología , Avispas/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Abejas/inmunología , Abejas/metabolismo , Reacciones Cruzadas , ADN Complementario/genética , Hialuronoglucosaminidasa/análisis , Datos de Secuencia Molecular , Peso Molecular , Estructura Terciaria de Proteína , Proteómica , Alineación de Secuencia , Especificidad de la Especie , Venenos de Avispas/química
10.
Braz. j. microbiol ; Braz. j. microbiol;40(2): 404-410, Apr.-June 2009. graf, tab
Artículo en Inglés | LILACS | ID: lil-520230

RESUMEN

Trichoderma is one of the fungi genera that produce important metabolites for industry. The growth of these organisms is a consequence of the nutritional sources used as also of the physical conditions employed to cultivate them. In this work, the automated Bioscreen C system was used to evaluate the influence of different nutritional sources on the growth of Trichoderma strains (T. hamatum, T. harzianum, T. viride, andT. longibrachiatum) isolated from the soil in the Juréia-Itatins Ecological Station (JIES), São Paulo State - Brazil. The cultures were grown in liquid culture media containing different carbon- (2%; w/v) and nitrogen (1%; w/v) sources at 28ºC, pH 6.5, and agitated at 150 rpm for 72 h. The results showed, as expected, that glucose is superior to sucrose as a growth-stimulating carbon source in the Trichoderma strains studied, while yeast extract and tryptone were good growth-stimulating nitrogen sources in the cultivation of T. hamatum and T. harzianum.


Trichoderma é um dos gêneros de fungos produtores de metabólitos de interesse industrial. O crescimento destes organismos é conseqüência das fontes nutricionais utilizadas, juntamente com as condições físicas de cultivo. Neste trabalho, o sistema automatizado Bioscreen C foi utilizado para avaliar a influência de diferentes fontes nutricionais sobre o crescimentode linhagens de Trichoderma (T. hamatum, T. harzianum, T. viride e T. longibrachiatum) isoladas do solo da Estação Ecológica da Juréia-Itatins (JIES), São Paulo - Brasil. Os cultivosforam feitos em meios líquidos de cultura contendo diferentes fontes de carbono (2%; w / v) e nitrogênio (1%; w / v) a 28ºC, pH 6,5 e agitados a 150 rpm durante 72 h. Os resultados mostraram, conforme esperado, que a glicose é melhor do que a sacarose como fonte de carbono indutora de crescimento das linhagens de Trichoderma testadas, enquanto que, o extrato de leveduras e a triptona foram boas fontes de nitrogênio indutorasde crescimento para os cultivos de T. hamatum e T. harzianum.


Asunto(s)
Fuentes Generadoras de Energía , Fungicidas Industriales/análisis , Medios de Cultivo/análisis , Trichoderma/crecimiento & desarrollo , Levaduras , Zonas Agrícolas/análisis , Ecología , Métodos , Evaluación Nutricional , Linaje , Métodos
11.
Braz J Microbiol ; 40(2): 404-10, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24031380

RESUMEN

Trichoderma is one of the fungi genera that produce important metabolites for industry. The growth of these organisms is a consequence of the nutritional sources used as also of the physical conditions employed to cultivate them. In this work, the automated Bioscreen C system was used to evaluate the influence of different nutritional sources on the growth of Trichoderma strains (T. hamatum, T. harzianum, T. viride, and T. longibrachiatum) isolated from the soil in the Juréia-Itatins Ecological Station (JIES), São Paulo State - Brazil. The cultures were grown in liquid culture media containing different carbon- (2%; w/v) and nitrogen (1%; w/v) sources at 28ºC, pH 6.5, and agitated at 150 rpm for 72 h. The results showed, as expected, that glucose is superior to sucrose as a growth-stimulating carbon source in the Trichoderma strains studied, while yeast extract and tryptone were good growth-stimulating nitrogen sources in the cultivation of T. hamatum and T. harzianum.

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