Person:
García-Fojeda García-Valdecasas, María Belén

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First Name
María Belén
Last Name
García-Fojeda García-Valdecasas
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Ciencias Químicas
Department
Bioquímica y Biología Molecular
Area
Bioquímica y Biología Molecular
Identifiers
UCM identifierORCIDScopus Author IDWeb of Science ResearcherIDDialnet IDGoogle Scholar ID

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Now showing 1 - 5 of 5
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    Project number: 163
    The Phantom Menace: Cómo salvar el mundo de una pandemia mediante Ingeniería Genética cooperativa
    (2021) Navarro LLorens, Juana María; Baldanta Callejo, Sara; Bénitez Prian, Mario; Blázquez Ortiz, Cristina; Bruñen Alfaro, Francisco; Cañadas Benito, Olga; Chinarro Sánchez, Adrián; García de la Camacha Selgas, Nuria; García-Fojeda García-Valdecasas, María Belén; Guevara Acosta, Flor Govinda; Leaño Hinojosa, Ariana; López Conejo, Maria Teresa; Lorente Pérez, Maria del Mar; Nogués Vera, Laura; Penalba Iglesias, Diana; Raisman, Andrea; Ranz Valdecasa, Maria Regina; Ruiz Ortega, Marta; Sánchez-Escalonilla Relea, Jose luis; Velasco Díez, Guillermo; Sánchez Torralba, Antonio
    El año pasado se llevó a cabo un proyecto de innovación (PIMCD-2019 174) basado en el modelo pedagógico de la clase invertida o “Flipped Classroom” y en el juego de mesa PANDEMIC (ASMODEE IBÉRICA). Brevemente, este proyecto consistió en una propuesta didáctica sobre los contenidos de FIGG en el que tomando como partida un entorno lúdico, los alumnos de FIGG en equipos preparaban contenidos y reforzaban conocimientos adquiridos en clase. Para llevarlo a cabo, a los alumnos se les planteaba una hipotética situación en la que cuatro enfermedades mortales aparecen en la tierra. Los alumnos divididos en equipos de 5 personas, deben cooperar desarrollando una serie de acciones que les permitan ir conociendo a qué patógeno se enfrentan y desarrollar herramientas que les permita controlar la epidemia dentro de un tiempo dado. Así cada equipo debe frenar el avance de las infecciones y a la vez encontrar una cura para la misma. Curiosamente, todo este escenario fue planteado antes de que la crisis del COVID-19 impactara en nuestra sociedad. En cualquier caso, la situación vivida en los últimos meses ha motivado a los estudiantes de FIGG por lo que en su mayor parte han participado en su desarrollo de manera entusiasta. En este nuevo proyecto, hemos tomado como base el proyecto del curso pasado, pero introduciendo algunos elementos innovadores. Entre estas innovaciones destaca la incorporación de dos alumnos por grupo de FIGG que ya lo hubieran realizado en la edición pasada por cada uno de los grupos de FIGG como mentores.
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    Project number: PIMCD327/23-24
    El poder de la nanotecnología lipídica: aplicaciones biotecnológicas de la asignatura Estructura de Membranas Biológicas
    (2024) Cañadas Benito, Olga; Ballesteros Aparicio, Sara; Cruz Rodríguez, Antonio; Espada Espinar, Adrián; Fuertes Vázquez, Lucía; García-Fojeda García-Valdecasas, María Belén; Gutiérrez Ramos, Irene
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    The collectin SP-A and its trimeric recombinant fragment protect alveolar epithelial cells from the cytotoxic and proinflammatory effects of human cathelicidin in vitro
    (Frontiers in Immunology, 2022) De Tapia Hernández, Lidia Consuelo; García-Fojeda García-Valdecasas, María Belén; Kronqvist, Nina; Johansson, Jan; Casals Carro, María Cristina
    Human cathelicidin (LL-37) is a defense peptide with antimicrobial activity against various pathogens. However, LL-37 can also trigger tissue injury by binding to host cell membranes. The cytotoxic effects of LL-37 may be especially relevant in chronic respiratory diseases characterized by increased LL-37. The aim of this study was to investigate whether the human collectin SP-A and a trimeric recombinant fragment thereof (rfhSP-A) can regulate the activities of LL-37. To this end, we studied the interaction of LL-37 with SP-A and rfhSP-A by intrinsic fluorescence, dynamic light scattering, and circular dichroism, as well as the effects of these proteins on the antimicrobial and cytotoxic activities of LL-37. Both SP-A and rfhSP-A bound LL-37 with high affinity at physiological ionic strength ( 0.45 ± 0.01 nM for SP-A and 1.22 ± 0.7 nM for rfhSP-A). Such interactions result in the reduction of LL-37-induced cell permeability and IL-8 release in human pneumocytes, mediated by P2X7 channels. Binding of LL-37 to SP-A did not modify the properties of SP-A or the antibacterial activity of LL-37 against respiratory pathogens (Pseudomonas aeruginosa, and nontypeable Haemophilus influenzae). SP-A/LL-37 complexes showed a greater ability to aggregate LPS vesicles than LL-37, which reduces endotoxin bioactivity. These results reveal the protective role of native SP-A in controlling LL-37 activities and suggest a potential therapeutic effect of rfhSP-A in reducing the cytotoxic and inflammatory actions of LL-37, without affecting its microbicidal activity against Gram-negative pathogens.
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    Airway allergy causes alveolar macrophage death, profound alveolar disorganization and surfactant dysfunction
    (Frontiers in Immunology, 2023) Feo-Lucas, Lidia; Godio, Cristina; Minguito de la Escalera, María ; Alvarez-Ladrón, Natalia ; Villarrubia, Laura; Vega-Pérez, Adrián ; González-Cintado, Leticia ; Domínguez-Andrés, Jorge; García-Fojeda García-Valdecasas, María Belén; Montero Fernández, Carlos; Casals Carro, María Cristina; Autilio, Chiara; Pérez Gil, Jesús; Crainiciuc, Georgiana ; Hidalgo, Andrés ; López-Bravo, María ; Fernández-Ardavín Castro, Carlos
    Respiratory disorders caused by allergy have been associated to bronchiolar inflammation leading to life-threatening airway narrowing. However, whether airway allergy causes alveolar dysfunction contributing to the pathology of allergic asthma remains unaddressed. To explore whether airway allergy causes alveolar dysfunction that might contribute to the pathology of allergic asthma, alveolar structural and functional alterations were analyzed during house dust mite (HDM)-induced airway allergy in mice, by flow cytometry, light and electron microscopy, monocyte transfer experiments, assessment of intra-alveolarly-located cells, analysis of alveolar macrophage regeneration in Cx3cr1cre:R26-yfp chimeras, analysis of surfactant-associated proteins, and study of lung surfactant biophysical properties by captive bubble surfactometry. Our results demonstrate that HDM-induced airway allergic reactions caused severe alveolar dysfunction, leading to alveolar macrophage death, pneumocyte hypertrophy and surfactant dysfunction. SP-B/C proteins were reduced in allergic lung surfactant, that displayed a reduced efficiency to form surface-active films, increasing the risk of atelectasis. Original alveolar macrophages were replaced by monocyte-derived alveolar macrophages, that persisted at least two months after the resolution of allergy. Monocyte to alveolar macrophage transition occurred through an intermediate stage of pre-alveolar macrophage and was paralleled with translocation into the alveolar space, Siglec-F upregulation, and downregulation of CX3CR1. These data support that the severe respiratory disorders caused by asthmatic reactions not only result from bronchiolar inflammation, but additionally from alveolar dysfunction compromising an efficient gas exchange.
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    Cooperative action of SP-A and its trimeric recombinant fragment with polymyxins against Gram-negative respiratory bacteria
    (Frontiers in Immunology, 2022) Coya, Juan Manuel ; Fraile Ágreda, Víctor; Tapia, Lidia de; García-Fojeda García-Valdecasas, María Belén; Sáenz, Alejandra ; Bengoechea, José; Kronqvist, Nina ; Johansson, Jan ; Casals Carro, María Cristina
    The exploration of therapies combining antimicrobial lung proteins and conventional antibiotics is important due to the growing problem of multidrug-resistant bacteria. The aim of this study was to investigate whether human SP-A and a recombinant trimeric fragment (rfhSP-A) have cooperative antimicrobial activity with antibiotics against pathogenic Gram-negative bacteria. We found that SP-A bound the cationic peptide polymyxin B (PMB) with an apparent dissociation constant (KD) of 0.32 ± 0.04 µM. SP-A showed synergistic microbicidal activity with polymyxin B and E, but not with other antibiotics, against three SP-A-resistant pathogenic bacteria:Klebsiella pneumoniae, non-typable Haemophilus influenzae (NTHi), and Pseudomonas aeruginosa. SP-A was not able to bind toK. pneumoniae, NTHi, or to mutant strains thereof expressing long-chain lipopolysaccharides (or lipooligosaccharides) and/or polysaccharide capsules. In the presence of PMB, SP-A induced the formation of SP-A/PMB aggregates that enhance PMB-induced bacterial membrane permeabilization. Furthermore, SP-A bound to a molecular derivative of PMB lacking the acyl chain (PMBN) with aKDof 0.26 ± 0.02 μM, forming SP-A/PMBN aggregates. PMBN has no bactericidal activity but can bind to the outer membrane of Gram-negative bacteria. Surprisingly, SP-A and PMBN showed synergistic bactericidal activity against Gram-negative bacteria. Unlike native supratrimeric SP-A, the trimeric rfhSP-A fragment had small but significant direct bactericidal activity against K. pneumoniae, NTHi, and P. aeruginosa. rfhSP-A did not bind to PMB under physiological conditions but acted additively with PMB and other antibiotics against these pathogenic bacteria. In summary, our results significantly improve our understanding of the antimicrobial actions of SP-A and its synergistic action with PMB. A peptide based on SP-A may aid the therapeutic use of PMB, a relatively cytotoxic antibiotic that is currently being reintroduced into clinics due to the global problem of antibiotic resistance.