https://phaidra.vetmeduni.ac.at/o:2432 Mesenchymal Stem Cell Conditioned Medium Modulates Inflammation in Tenocytes: Complete Conditioned Medium Has Superior Therapeutic Efficacy than Its Extracellular Vesicle Fraction Soukup, Robert Robert Soukup University of Veterinary Medicine Vienna Jenner, Florien Florien Jenner 0000-0002-6977-1984 University of Veterinary Medicine Vienna / Austrian Cluster for Tissue Regeneration Grillari, Johannes Johannes Grillari 0000-0001-5474-6332 Austrian Cluster for Tissue Regeneration / Ludwig Boltzmann Institute for Traumatology / University of Natural Resources and Life Sciences Vienna Gueltekin, Sinan Sinan Gueltekin 0000-0002-4962-8451 University of Veterinary Medicine Vienna Gerner, Iris Iris Gerner 0000-0001-6618-2669 University of Veterinary Medicine Vienna / Austrian Cluster for Tissue Regeneration Mohr, Thomas Thomas Mohr 0000-0002-1933-847X Science Consult DI Thomas Mohr KG / Medical University of Vienna / University of Vienna MDPI text eng Tendinopathy, a prevalent overuse injury, lacks effective treatment options, leading to a significant impact on quality of life and socioeconomic burden. Mesenchymal stem/stromal cells (MSCs) and their secretome, including conditioned medium (CM) and extracellular vesicles (EVs), have shown promise in tissue regeneration and immunomodulation. However, it remains unclear which components of the secretome contribute to their therapeutic effects. This study aimed to compare the efficacy of CM, EVs, and the soluble protein fraction (PF) in treating inflamed tenocytes. CM exhibited the highest protein and particle concentrations, followed by PF and EVs. Inflammation significantly altered gene expression in tenocytes, with CM showing the most distinct separation from the inflamed control group. Treatment with CM resulted in the most significant differential gene expression, with both upregulated and downregulated genes related to inflammation and tissue regeneration. EV treatment also demonstrated a therapeutic effect, albeit to a lesser extent. These findings suggest that CM holds superior therapeutic efficacy compared with its EV fraction alone, emphasizing the importance of the complete secretome in tendon injury treatment. Bone-Marrow; Tendon Injuries; Ischemic-Heart; In-Vitro; Mechanisms; Migration; Secretome; Collagen; Model; Cytokines http://creativecommons.org/licenses/by/4.0/ https://phaidra.vetmeduni.ac.at/api/object/o:2432/download 10.3390/ijms241310857 https://phaidra.vetmeduni.ac.at/o:605 application/pdf International Journal of Molecular Sciences 24(13) (2023) International Journal of Molecular Sciences 24 13 753.26 kB 2023