Macrophage-bacteria interactions: a 3d microfluidics-based approach
- Autores: Sandra Pérez Rodríguez
- Directores de la Tesis: Jesús Gonzalo Asensio (dir. tes.), José Manuel García Aznar (dir. tes.)
- Lectura: En la Universidad de Zaragoza ( España ) en 2022
- Idioma: inglés
- Tribunal Calificador de la Tesis: Mª Henar Alonso Ezcurra (presid.), Juan Ignacio Aguiló Anento (secret.), Mar Cóndor Salgado (voc.)
- Programa de doctorado: Programa de Doctorado en Ingeniería Biomédica por la Universidad Politécnica de Catalunya y la Universidad de Zaragoza
- Materias:
- Enlaces
- Tesis en acceso abierto en: Zaguán
- Resumen
Bacterial infections cause numerous deaths annually, so it is essential to understand the infection processes in order to develop prevention and cure strategies. Usually, in vitro studies are performed with traditional methods that, despite providing great knowledge, do not realistically recreate physiological environments and the results obtained do not always agree with in vivo studies. Therefore, in this thesis we propose microfluidic devices as a novel in vitro model for the study of these processes. Microfluidics allows the incorporation of three-dimensionality, flow and co-cultures, among others, to achieve scenarios that are more realistic. Since pathogenic infections are long multistage processes, in this thesis, we focused on the macrophage-pathogen interaction.
First, the extravasation of monocytes from the endothelial lumen into the extracellular matrix was studied. This process is necessary for immune cells to reach bacteria. For this purpose, a microfluidic device was used that allowed the development of an endothelial vessel through which monocytes were passed, allowing the quantification of adherent and extravasated monocytes after 24 hours. The effect of mechanical stimuli on this process was analyzed: the application of oscillatory flow and environmental stiffness. It was determined that flow increased the membrane integrity of the vessel, hindering monocyte extravasation. However, higher stiffness of the extracellular matrix, due to high collagen concentration, reduced the barrier integrity of the vessel, increasing monocyte extravasation.
Second, macrophage migration was studied in response to bacterial fractions obtained from pathogenic bacteria, Salmonella typhimurium and Mycobacterium tuberculosis, and non-pathogenic bacteria, Escherichia coli and Mycobacterium smegmatis. The results show that macrophages migrate directionally attracted to fractions of all bacteria, both pathogenic and non-pathogenic, suggesting the existence of pathogen-associated molecular patterns in the sample molecules.
