This study investigates the therapeutic potential of human placental mesenchymal stem cells (P-MSCs) and their extracellular vesicles (EVs) in a murine model of acute respiratory distress syndrome (ARDS), a condition with growing relevance due to its association with severe COVID-19. We induced ARDS-like lung injury in mice using intranasal LPS instillation and evaluated histological changes, neutrophil accumulation via immunohistochemistry, bronchoalveolar lavage fluid cell count, total protein, and cytokine concentration, as well as lung gene expression changes at three time points: 24, 72, and 168 h. We found that both P-MSCs and EV treatments reduced the histological evidence of lung injury, decreased neutrophil infiltration, and improved alveolar barrier integrity.
View Article and Find Full Text PDFBackground: Although BRAF/MEK inhibitors improved the treatment of melanoma patients, resistance is acquired almost inevitably.
Methods: Trametinib withdrawal/rechallenge and MCL-1 inhibition in trametinib-resistance models displaying distinct p-ERK1/2 levels were investigated.
Results: Trametinib withdrawal/rechallenge caused reversible changes in ERK1/2 activity impacting the balance between pro-survival and pro-apoptotic proteins.
Despite significant advances in targeted therapies against the hyperactivated BRAF/MEK pathway for patients with unresectable metastatic melanoma, acquired resistance remains an unsolved clinical problem. In this study, we focused on melanoma cells resistant to trametinib, an agent broadly used in combination therapies. Molecular and cellular changes were assessed during alternating periods of trametinib withdrawal and rechallenge in trametinib-resistant cell lines displaying either a differentiation phenotype (MITF/NGFR) or neural crest stem-like dedifferentiation phenotype (NGFR/MITF).
View Article and Find Full Text PDFExtracellular vesicles (EVs) are a heterogeneous group of cell-secreted particles that carry cargo of functional biomolecules crucial for cell-to-cell communication with both physiological and pathophysiological consequences. In this review, we focus on evidence demonstrating that the EV-mediated crosstalk between melanoma cells within tumor, between melanoma cells and immune and stromal cells, promotes immune evasion and influences all steps of melanoma development from local progression, pre-metastatic niche formation, to metastatic colonization of distant organs. We also discuss the role of EVs in the development of resistance to immunotherapy and therapy with BRAF/MEK inhibitors, and shortly summarize the recent advances on the potential applications of EVs in melanoma diagnostics and therapy.
View Article and Find Full Text PDFSmall extracellular vesicles (sEVs) including exosomes are produced by all cell types and can be isolated from biological fluids and cell culture supernatants. The separation of exosomes with high purity from protein-rich media remains challenging. Besides contaminating proteins, small microvesicles (MVs) and apoptotic bodies are usually co-isolated with exosomes.
View Article and Find Full Text PDFExtracellular vesicles (EVs) have attracted considerable interest due to their role in cell-cell communication, disease diagnosis, and drug delivery. Despite their potential in the medical field, there is no consensus on the best method for separating micro- and nanovesicles from cell culture supernatant and complex biological fluids. Obtaining a good recovery yield and preserving physical characteristics is critical for the diagnostic and therapeutic use of EVs.
View Article and Find Full Text PDFBackground: Exosomes open exciting new opportunities for advanced drug transport and targeted release. Furthermore, exosomes may be used for vaccination, immunosuppression or wound healing. To fully utilize their potential as drug carriers or immune-modulatory agents, the optimal purity of exosome preparations is of crucial importance.
View Article and Find Full Text PDFAtherogenesis is associated with chronic gut infections; however, the mechanisms are not clear. The aim of the study was to determine whether lipopolysaccharide of E. coli (E.
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