Bronchial Challenge With Tri a 14 as an Alternative Diagnostic Test for Baker's Asthma

BACKGROUND: Baker's asthma (BA) is the most prevalent occupational respiratory disease in developed countries. It is caused by inhalation of wheat dust in the working environment and affects 1%-10% of workers in the baking industry. Diagnosis of BA is based on bronchial challenge with wheat, a technique that carries a high risk for patients. The wheat lipid transfer protein Tri a 14 is a major allergen in BA. OBJECTIVE: The aim of our study was to characterize Tri a 14 as a marker of BA in order to prevent patients from having to undergo bronchial challenge with wheat. METHODS: The study population comprised 55 patients selected at the Rio Hortega Hospital, Valladolid, Spain. Patients with BA were diagnosed using a skin prick test (SPT) with wheat and Tri a 14 and bronchial challenge test (BCT) with wheat. Patients with food allergy had a clear clinical history of allergy to peach confirmed by positive SPT to peach extract and Pru p 3. RESULTS: All patients in the BA group had a positive SPT result with wheat (100%), and most had positive results with Tri a 14 (95%). A positive BCT result with Tri a 14 was also observed in 22 of 27 of the patients with BA (82%). The response to Tri a 14 was specifically associated with BA. CONCLUSION: Tri a 14 is a good marker of BA and can be used in SPT and BCT as an alternative diagnostic method, thus avoiding bronchial challenge with wheat and reducing the risk associated with this technique

LPS promotes Th2 dependent sensitisation leading to anaphylaxis in a Pru p 3 mouse model

Pru p 3 is the major peach allergen in the Mediterranean area. It frequently elicits severe reactions, limiting its study in humans, raising the need for animal models to investigate the immunological mechanisms involved. However, no anaphylaxis model exists for Pru p 3. We aimed to develop a model of peach anaphylaxis by sensitising mice with Pru p 3 in combination with lipopolysaccharide (LPS) as an adjuvant. Four groups of mice were sensitised intranasally: untreated; treated with Pru p 3; treated with LPS; treated with Pru p 3 + LPS. After sensitisation mice were intraperitoneally challenged with Pru p 3 and in vivo and in vitro parameters were evaluated. Only mice in the Pru p 3 + LPS group showed anaphylaxis symptoms, including a decrease in temperature. Determination of in vitro parameters showed a Th2 response with an increase of Pru p 3-specific IgE and IgG1. Moreover, at the cellular level, we found increased levels of IgE and IgG1 secreting Pru p 3-specific cells and a proliferative CD4+ T-cell response. These results demonstrate that Pru p 3-specific anaphylaxis can be generated after nasal sensitisation to Pru p 3 in combination with LPS. This is a promising model for evaluating food allergy immunotherapies.Unión Europea, Ministerio de Economía y Competitividad, Instituto de Salud "Carlos III" PI12 / 02481Unión Europea, Ministerio de Economía y Competitividad, Instituto de Salud "Carlos III" PI15 / 00559Unión Europea, Ministerio de Economía y Competitividad, Instituto de Salud "Carlos III" RD 07/0064Unión Europea, Ministerio de Economía y Competitividad, Instituto de Salud "Carlos III" RD12 / 0013/0001Unión Europea, Ministerio de Economía y Competitividad, Instituto de Salud "Carlos III" RD07 / 0064/0003Unión Europea, Ministerio de Economía y Competitividad, Instituto de Salud "Carlos III" RD12 / 0013/0016Unión Europea, Ministerio de Andalucía Economía y Conocimiento CTS-7433Unión Europea, Ministerio de Andalucía Economía y Conocimiento C-0044-2012 SAS2013Unión Europea, Ministerio de Andalucía Economía y Conocimiento Ref. CD14 / 00242Unión Europea, Ministerio de Andalucía Economía y Conocimiento BIO2013- 41403-

Impact of quality-indicator-based measures to improve the treatment of acute poisoning in pediatric emergency patients

Objetivo. Analizar el impacto de la aplicación de medidas de mejora implementadas a partir de la evaluación de indicadores de calidad (IC) en la atención prestada a los pacientes pediátricos con intoxicación aguda. Método. Se compara el resultado actual de los IC con el estándar deseado y con el resultado obtenido en dos estudios previos. Estudio-1: evaluación de 6 IC básicos en los servicios de urgencias pediátricas (SUP) participantes en el Grupo de Trabajo de Intoxicaciones de la Sociedad Española de Urgencias Pediátricas (GTI-SEUP). Estudio-2: evaluación de los 20 IC en uno de los servicios de urgencias del GTI-SEUP. Tras la realización de los mismos se implementaron medidas correctoras: grupo de seguimiento de lavado gástrico, reedición del manual de intoxicaciones del GTI-SEUP, implementación del protocolo de atención al paciente intoxicado y creación de campos específicos en la historia clínica informatizada. Resultados. Estudio-1: se alcanza el estándar en 4 IC y mejora la disponibilidad de protocolos (el IC supera el estándar en el 100% de SUP vs el 29,2% previo; p < 0,001) sin cambios significativos en el resto de IC. Estudio-2: se alcanza el estándar en 13 IC y mejora de los IC sobre cumplimentación de parte judicial (44,4% vs 19,2%; p = 0,036), registro del Conjunto Mínimo de Datos (51,0% vs 1,9%; p < 0,001) y tendencia al aumento de administración de carbón activado en las primeras 2 horas (93,1% vs 83,5%; p = 0,099). No existen cambios significativos en el resto de IC. Conclusiones. La implementación de medidas correctoras ha dado lugar a una mejora en el resultado de algunos IC. La calidad de la asistencia de estos pacientes es aún mejorable

Characterization of the Biological Activity of Pru p 3 in Plant and Intestinal Epithelium

La alergia es un problema social que supone una grave disminución de la calidad de vida del paciente, estando considerada como la mayor enfermedad crónica en Europa en la actualidad. Desde mediados del siglo XX, se ha producido un incremento en la prevalencia de esta enfermedad aunque el origen de este incremento es todavía desconocido. Para prevenir y tratar este tipo de enfermedades es necesario conocer el mecanismo por el cual una proteína se convierte en alergénica. El objetivo principal de esta Tesis ha sido estudiar los mecanismos moleculares que están implicados en los procesos de sensibilización alérgica. Evidencias crecientes sugieren que los lípidos transportados por determinados alérgenos pueden ser reconocidos por receptores celulares del sistema inmune, pudiendo tener un papel destacado en la sensibilización alérgica. En este trabajo se ha escogido como modelo Pru p 3, alérgeno principal del melocotón y proteína transportadora de lípidos, (lipid transfer protein, LTP). El ligando lipídico de Pru p 3 se ha caracterizado estructuralmente por primera vez empleando ESI-micrOTOF-QII. Así, el ligando se ha identificado como un derivado hidroxilado de camptotecina unida a fitoesfingosina, segmento que forma una cola hidrocarbonada que se inserta en el túnel hidrofóbico de la proteína. La naturaleza química del ligando ha sido confirmada mediante ensayos de inhibición de la topoisomerasa I y emisión de fluorescencia a 254 nm, ambas características típicas de la camptotecina. Por otra parte, combinando diferentes técnicas in vitro (como RT-PCR e inmunohistoquímica), se ha caracterizado el posible papel del ligando en planta. La máxima expresión de Pru p 3 se detectó en los estilos de flores polinizadas, en contraste con su ausencia en no polinizados donde su expresión disminuye tras la antítesis. Además, la mayor expresión de Pru p 3 se localizó en piel, más concretamente en los tricomas, pero no en la pulpa. Estos datos, junto con la inhibición de la germinación del polen por parte del ligando, sugieren que Pru p 3 puede inhibir una segunda polinización y mantener alejados los herbívoros hasta la maduración de la semilla. Igualmente, se ha evaluado la actividad inmunológica del ligando lipídico empleando diferentes modelos in vitro (como moDC, PBMCs, THP1 y células epiteliales como Caco2) y un modelo de ratón de anafilaxia. Así se ha determinado que el ligando es capaz de modular el sistema inmune a través de una respuesta Th2, siendo el responsable de la activación de las células presentadoras de antígeno y aumenta la capacidad de sensibilización alérgica a Pru p 3 en el modelo de ratón. Además, el ligando es presentado por el receptor CD1d en las células epiteliales, activando a continuación las células iNKT. Estos resultados se han confirmado con un empleo del modelo ex vivo InTESTineTM con fragmentos de tejido de cerdo. De este modo se ha podido observar que el ligando no afecta al transporte de Pru p 3 a través de la barrera intestinal aunque parece que Pru p 3 queda acumulado en las Placas de Peyer. Por otra parte, se ha observado que la presencia del ligando induce la expresión de citoquinas típicas de una respuesta Th2 como IL4 e IL13. Igualmente se ha confirmado que Pru p 3 co-localiza con el receptor CD1d en presencia del ligando y que aumenta la presencia de células iNKT. En resumen, este trabajo representa un nuevo enfoque sobre los mecanismos que caracterizan la alergia, aportando resultados de gran utilidad tanto para la mejora del diagnóstico como para nuevas investigaciones sobre esta enfermedad. ----------ABSTRACT---------- Allergy is a serious social problem that impairs the quality of life of patients and is currently considered the most prevalent chronic disease in Europe. A large increase in its prevalence has occurred since the mid-twentieth century. However, the underlying causes for this increase and the factors that trigger allergy are still unknown. Knowing why a protein becomes an allergen would be essential in the prevention and treatment of allergy diseases. The main aim of this doctoral thesis was to study the molecular mechanisms involved in the allergic sensitization processes. Increasing evidence suggests that lipids transported by certain allergens can be recognized by cellular receptors of the immune system, and may play a prominent role in allergic sensitization. In this work, Pru p 3, the major allergen of the peach and a lipid-transfer protein (LTP), has been chosen as model. The lipid ligand of Pru p 3 has been structurally characterized for the first time using ESI-micrOTOF-QII. The ligand has thus been identified as a hydroxyl derivative of camptothecin bound to phytosphingosine, a hydrocarbon tail which is inserted into the hydrophobic tunnel of the protein. This result was validated by assays of inhibition of topoisomerase I as well as fluorescence emission at 254 nm, both features characteristic of camptothecin. Additionally, different in vitro techniques (such as RT-PCR and immunohistochemistry) were combined to characterize the possible role of the ligand in plant. The highest expression of Pru p 3 was detected in pollinated styles by contrast to its absence in non-pollinated flowers where the expression decreased after the antithesis. Besides, the highest expression of Pru p 3 was localized in the tricomas, but not in the pulp. These data, together with the inhibition of pollen germination by the ligand, suggest that Pru p 3 can inhibit a secondary pollination and keep herbivores away until seed maturation. Additionally, the immunological activity of the lipid ligand was evaluated using different in vitro models (moDC, PBMCs, THP1, and Caco2) and a mouse model of anaphylaxis. Thus, it was determined that the ligand was capable of modulating the immune system through a Th2 response, responsible for the activation of antigen presenting cells, and in increasing the capacity of allergic sensitization to Pru p 3 in a mouse model. Furthermore, the ligand was introduced by the CD1d receptor into the epithelial cells to activate iNKT cells. These results have been validated using the ex vivo model InTESTineTM with fragments of pig tissue. The ligand did not affect the transport of Pru p 3 through the intestinal barrier, but appears to remain accumulated in Peyer's Patches. The presence of the ligand was also observed to induce the expression of cytokines that are typical of a Th2 response like IL4 and IL13. Moreover, it was confirmed that Pru p 3 co-localized with the CD1d receptor in the presence of the ligand, as well as increasing the presence of iNKT cells. In summary, this thesis work represents a novel approach to characterize allergic response mechanisms and presents results which are useful for improving diagnosis and for providing a basis for new investigations related to allergy

Computational study of pH-dependent oligomerization and ligand binding in Alt a 1, a highly allergenic protein with a unique fold

Alt a 1 is a highly allergenic protein from Alternaria fungi responsible for several respiratory diseases. Its crystal structure revealed a unique β-barrel fold that defines a new family exclusive to fungi and forms a symmetrical dimer in a butterfly-like shape as well as tetramers. Its biological function is as yet unknown but its localization in cell wall of Alternaria spores and its interactions in the onset of allergy reactions point to a function to transport ligands. However, at odds with binding features in β-barrel proteins, monomeric Alt a 1 seems unable to harbor ligands because the barrel is too narrow. Tetrameric Alt a 1 is able to bind the flavonoid quercetin, yet the stability of the aggregate and the own ligand binding are pH-dependent. At pH 6.5, which Alt a 1 would meet when secreted by spores in bronchial epithelium, tetramer-quercetin complex is stable. At pH 5.5, which Alt a 1 would meet in apoplast when infecting plants, the complex breaks down. By means of a combined computational study that includes docking calculations, empirical pKa estimates, Poisson–Boltzmann electrostatic potentials, and Molecular Dynamics simulations, we identified a putative binding site at the dimeric interface between subunits in tetramer. We propose an explanation on the pH-dependence of both oligomerization states and protein–ligand affinity of Alt a 1 in terms of electrostatic variations associated to distinct protonation states at different pHs. The uniqueness of this singular protein can thus be tracked in the combination of all these features

Computational study of pH-dependent oligomerization and ligand binding in Alt a 1, a highly allergenic protein with a unique fold

Alt a 1 is a highly allergenic protein from Alternaria fungi responsible for several respiratory diseases. Its crystal structure revealed a unique ?-barrel fold that defines a new family exclusive to fungi and forms a symmetrical dimer in a butterfly-like shape as well as tetramers. Its biological function is as yet unknown but its localization in cell wall of Alternaria spores and its interactions in the onset of allergy reactions point to a function to transport ligands. However, at odds with binding features in ?-barrel proteins, monomeric Alt a 1 seems unable to harbor ligands because the barrel is too narrow. Tetrameric Alt a 1 is able to bind the flavonoid quercetin, yet the stability of the aggregate and the own ligand binding are pH-dependent. At pH 6.5, which Alt a 1 would meet when secreted by spores in bronchial epithelium, tetramer-quercetin complex is stable. At pH 5.5, which Alt a 1 would meet in apoplast when infecting plants, the complex breaks down. By means of a combined computational study that includes docking calculations, empirical pKa estimates, Poisson?Boltzmann electrostatic potentials, and Molecular Dynamics simulations, we identified a putative binding site at the dimeric interface between subunits in tetramer. We propose an explanation on the pH-dependence of both oligomerization states and protein?ligand affinity of Alt a 1 in terms of electrostatic variations associated to distinct protonation states at different pHs. The uniqueness of this singular protein can thus be tracked in the combination of all these features

Identification of the ligand of Pru p 3, a peach LTP

The allergen Pru p 3, a peach lipid transfer protein, has been well studied. However, its physiological function remains to be elucidated. Our results showed that Pru p 3 usually carries a lipid ligand that play an essential role in its function in plants. Using ESI-qToF, we observed that the ligand was a derivative of camptothecin binding to phytosphingosine, wich that is inserted into the hydrophobic tunnel of the protein. In addition, the described ligand displayed topoisomerase I activity inhibition and self-fluorescence, both recognized as camptothecin properties. During flower development, the highest expression of Pru p 3 was detected in the styles of pollinated flowers, in contrast to its non-expression in unpollinated pistils, where expression decreased after anthesis. During ripening, the expression of Pru p 3 were observed mainly in peel but not in pulp. In this sense, Pru p 3 protein was also localized in trichomes covering the fruit epidermis

Impact of quality-indicator-based measures to improve the treatment of acute poisoning in pediatric emergency patients

Objetivo. Analizar el impacto de la aplicación de medidas de mejora implementadas a partir de la evaluación de indicadores de calidad (IC) en la atención prestada a los pacientes pediátricos con intoxicación aguda. Método. Se compara el resultado actual de los IC con el estándar deseado y con el resultado obtenido en dos estudios previos. Estudio-1: evaluación de 6 IC básicos en los servicios de urgencias pediátricas (SUP) participantes en el Grupo de Trabajo de Intoxicaciones de la Sociedad Española de Urgencias Pediátricas (GTI-SEUP). Estudio-2: evaluación de los 20 IC en uno de los servicios de urgencias del GTI-SEUP. Tras la realización de los mismos se implementaron medidas correctoras: grupo de seguimiento de lavado gástrico, reedición del manual de intoxicaciones del GTI-SEUP, implementación del protocolo de atención al paciente intoxicado y creación de campos específicos en la historia clínica informatizada. Resultados. Estudio-1: se alcanza el estándar en 4 IC y mejora la disponibilidad de protocolos (el IC supera el estándar en el 100% de SUP vs el 29,2% previo; p < 0,001) sin cambios significativos en el resto de IC. Estudio-2: se alcanza el estándar en 13 IC y mejora de los IC sobre cumplimentación de parte judicial (44,4% vs 19,2%; p = 0,036), registro del Conjunto Mínimo de Datos (51,0% vs 1,9%; p < 0,001) y tendencia al aumento de administración de carbón activado en las primeras 2 horas (93,1% vs 83,5%; p = 0,099). No existen cambios significativos en el resto de IC. Conclusiones. La implementación de medidas correctoras ha dado lugar a una mejora en el resultado de algunos IC. La calidad de la asistencia de estos pacientes es aún mejorable

Characterisation of a flavonoid ligand of the fungal protein Alt a 1

Spores of pathogenic fungi are virtually ubiquitous and cause human disease and severe losses in crops. The endophytic fungi Alternaria species produce host-selective phytotoxins. Alt a 1 is a strongly allergenic protein found in A. alternata that causes severe asthma. Despite the well-established pathogenicity of Alt a 1, the molecular mechanisms underlying its action and physiological function remain largely unknown. To gain insight into the role played by this protein in the pathogenicity of the fungus, we studied production of Alt a 1 and its activity in spores. We found that Alt a 1 accumulates inside spores and that its release with a ligand is pH-dependent, with optimum production in the 5.0-6.5 interval. The Alt a 1 ligand was identified as a methylated flavonoid that inhibits plant root growth and detoxifies reactive oxygen species. We also found that Alt a 1 changes its oligomerization state depending on the pH of the surrounding medium and that these changes facilitate the release of the ligand. Based on these results, we propose that release of Alt a 1 should be a pathogenic target in approaches used to block plant defenses and consequently to favor fungal entry into the plant

Pru p 3‐Epitope‐based sublingual immunotherapy in a murine model for the treatment of peach allergy

[Scope] Food‐specific immunotherapy (SIT) is a promising treatment for lipid transfer protein (LTP)‐syndrome. We propose a novel sublingual‐SIT (SLIT) that combines a Pru p 3 T‐cell peptide and an oligodeoxyribonucleotide (ODN) with CpG motifs (ODN‐CpG) as adjuvants to induce a specific Th1/Treg response.[Methods and results] LTP‐peach allergic mice were treated sublingually with a combination of a CpG sequence and mono‐ or tetravalent systems including a Pru p 3 peptide, D1(Prup3) or D4(Prup3). Mice were challenged intraperitoneally with Pru p 3 one or three weeks after SLIT and tolerance was assessed. Mice treated with D1(Prup3)+CpG were protected from anaphylaxis after Pru p 3 challenge. They showed no change in body temperature, lower levels of Pru p 3‐specific IgE and IgG1 antibodies and higher levels of sIgG2a compared to the untreated group. They had fewer IgE and IgG1 secreting cells and more sIgG2a secreting cells. Moreover, a significantly lower number of Pru p 3‐specific CD4+T cells and a higher number of Treg cells were found, alongside a Th1 cytokine pattern. These changes were maintained for three weeks after stopping treatment.[Conclusion] D1Prup3+CpG represents a promising SIT for food allergy. It is easily synthesized and induces protection from anaphylaxis to Pru p 3 that is maintained for at least three weeks.The study was funded by the Institute of Health “Carlos III” of the Ministry of Economy and Competitiveness: PI12/02481 and PI15/00559, RETICS RIRAAF (RD12/0013/0001, RD12/0013/0014, RD12/0013/0016), RETICS ARADyAL (RD16/0006/0001 RD16/0006/0003 and RD16/0006/0011) and Sara Borrell Program (CD14/00242). Andalusian Regional Ministry of Economy and Knowledge: CTS‐7433), Nicolas Monardes Program (C‐0044‐2012 SAS2013) and the Spanish Ministry of Economy and Competitiveness (CTQ2014‐52328‐P and AGL2014‐52395‐C2‐2). Grants were cofunded by the European Regional Development Fund (ERDF).Peer reviewe