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Leon Icaza, S. A.

Publications and source records attributed to Leon Icaza, S. A..

2 recordsLinked to original sources

Cystic fibrosis patient-derived bronchial organoids unveil druggable pathways against Mycobacterium abscessus infection.

Mycobacterium abscessus (Mabs) drives life-shortening mortality in cystic fibrosis (CF) patients, primarily because of its resistance to chemotherapeutic agents. To date, our knowledge on the host and bacterial determinants driving Mabs pathology in CF patient lung remains rudimentary. Here, we used human airway organoids (AOs) microinjected with smooth (S) or rough (R-)Mabs to evaluate bacteria fitness, host responses to infection, and new treatment efficacy. We show that S Mabs formed biofilm, R Mabs formed cord serpentines and displayed a higher virulence. While Mabs infection triggers enhanced oxidative stress, pharmacological activation of antioxidant pathways resulted in better control of Mabs growth. Genetic and pharmacological inhibition of the CFTR is associated with better growth and higher virulence of S and R Mabs. Finally, pharmacological activation of antioxidant pathways inhibited Mabs growth and improved efficacy in combination with cefoxitin, a first line antibiotic. In conclusion, we have established AOs as a suitable human system to decipher mechanisms of CF-driven respiratory infection by Mabs and propose antioxidants as a potential host-directed strategy to improve Mabs infection control.

cell biology↗

Mycobacteria-host interactions in human bronchiolar airway organoids

Tuberculosis, one of the oldest human pathogens remains a major global health threat. Recent advances in organoid technology offer a unique opportunity to grow different human "organs" in vitro, including the human airway, that faithfully recapitulate tissue architecture and function. We have explored the potential of human airway organoids (AOs) as a novel system in which to model tuberculosis infection. To this end, we adapted biosafety containment level 3-approved procedures to allow successful microinjection of Mycobacterium tuberculosis, the causative agent of tuberculosis, into AOs. We reveal that mycobacteria infected epithelial cells with low efficiency, and that the organoid microenvironment was able to control, but not eliminate the pathogen. We demonstrate that AOs responded to infection by inducing cytokine and antimicrobial peptide production, and inhibiting mucins. Given the importance of myeloid cells in tuberculosis infection, we co-cultured mycobacteria-infected organoids with human monocyte-derived macrophages, and found that these cells were recruited to the organoid epithelium. We conclude that adult stem cell-derived airway organoids can be used to model early events of tuberculosis infection and offer new avenues for fundamental and therapeutic research.

systems biology↗