Optimization of the Amplification of Equine Muscle-Derived Mesenchymal Stromal Cells in a Hollow-Fiber Bioreactor.

The main causes of mortality in horses are the gastrointestinal pathologies associated with septic shock. Stem cells have shown, through systemic injection, a capacity to decrease inflammation and to regenerate injured tissue faster. Nevertheless, to achieve this rapid and total regeneration, systemic injections of 1 to 2 million cells per kilogram of body weight must be considered. Here, we demonstrate for the first time the feasibility and expansion capacity of equine muscle-derived mesenchymal stromal cells (mdMSCs) in a functionally closed, automated, perfusion-based, hollow-fiber bioreactor (HFBR) called the Quantum™ Cell Expansion System (Terumo Blood and Cell Technologies). This feature greatly increases the number of generated cells with a surface area of 1.7 m2. The expansion of mdMSCs is very efficient in this bioreactor. The maximum expansion generated twenty times more cells than the initial seeding in nine days. The best returns were observed with an optimal seeding between 10 and 25 million mdMSCs, using the Bull's eye loading method and with a run duration between 7 and 10 days. Moreover, all the generated cells kept their stem properties: the ability to adhere to plastic and to differentiate into chondroblasts, osteoblasts and adipocytes. They also showed the expression of CD-44 and CD-90 markers, with a positive rate above 93%, while CD-45 and MHCII were non-expressed, with a positive rate below 0.5%. By capitalizing on the scalability, automation and 3D culture capabilities of the Quantum™, it is possible to generate large quantities of high-quality equine mdMSCs for gastrointestinal disorders and other clinical applications.

Equine Muscle Derived Mesenchymal Stem Cells Loaded with Water-Soluble Curcumin: Modulation of Neutrophil Activation and Enhanced Protection against Intracellular Oxidative Attack.

We investigated the antioxidant potential of equine mesenchymal stem cells derived from muscle microbiopsies (mdMSCs), loaded by a water-soluble curcumin lysinate incorporated into hydroxypropyl-ß-cyclodextrin (NDS27). The cell loading was rapid and dependent on NDS27 dosage (14, 7, 3.5 and 1 µM). The immunomodulatory capacity of loaded mdMSCs was evaluated by ROS production, on active and total myeloperoxidase (MPO) degranulation and neutrophil extracellular trap (NET) formation after neutrophil stimulation. The intracellular protection of loaded cells was tested by an oxidative stress induced by cumene hydroperoxide. Results showed that 10 min of mdMSC loading with NDS27 did not affect their viability while reducing their metabolism. NDS27 loaded cells in presence of 14, 7 µM NDS27 inhibited more intensively the ROS production, the activity of the MPO released and bound to the NET after neutrophil stimulation. Furthermore, loaded cells powerfully inhibited intracellular ROS production induced by cumene as compared to control cells or cyclodextrin-loaded cells. Our results showed that the loading of mdMSCs with NDS27 significantly improved their antioxidant potential against the oxidative burst of neutrophil and protected them against intracellular ROS production. The improved antioxidant protective capacity of loaded mdMSCs could be applied to target inflammatory foci involving neutrophils.