Impact of pro-inflammatory cytokine preconditioning on metabolism and extracellular vesicles in feline mesenchymal stromal cells: a preliminary study.

Abstract

Extracellular vesicles (EVs) derived from mesenchymal stem cells have shown promise in treating inflammation. This study investigates whether preconditioning feline adipose-derived stem cells (FeASCs) with inflammatory cytokines, specifically IFN-γ and TNF-α, enhances the anti-inflammatory efficacy of MSC-derived EVs. We hypothesize that cytokine-primed FeASCs will produce EVs with improved anti-inflammatory properties and that this preconditioning will affect mitochondrial dynamics to enhance EV therapy effectiveness. FeASCs were exposed to a TNF-α/IFN-γ combination to mimic a pro-inflammatory milieu favoring ASCs' immunosuppressive phenotype. We analyzed morphological, metabolic, and immunomodulatory characteristics of native and cytokine-primed FeASCs. EVs were assessed for anti-inflammatory and mitochondrial-related markers. We also evaluated mitochondrial function and apoptosis markers in cytokine-primed cells. Cytokine priming led to significant morphological changes in FeASCs, including enhanced cell projections and increased apoptosis. EVs from cytokine-primed FeASCs exhibited a heightened immunomodulatory profile, with increased expression of both pro-inflammatory and anti-inflammatory mediators. Transcriptomic analysis of these EVs revealed the upregulation of genes associated with cell proliferation, survival, and apoptosis. Mitochondrial function was impaired in cytokine-primed cells, but mitochondrial morphology remained unchanged. EVs from these cells contained higher levels of mitochondrial-related transcripts, indicating a compensatory response. Cytokine-primed FeASCs generate EVs with enhanced immunomodulatory potential, highlighting their therapeutic promise. However, further research is needed to validate their efficacy and safety and refine preconditioning strategies to optimize EV-based therapies for inflammatory conditions. These advancements could pave the way for broader applications in regenerative medicine.