Comparison of biological activity in vitro by the secretion of mesenchymal stem cells isolated from adipose tissue

Today, regenerative medicine, traditionally reliant on stem cell therapy, is shifting toward a new type of biological regulation based on intercellular interactions via secreted substances known as the secretome. The use of mesenchymal stem cell (MSC) secretomes in regenerative therapy offers several advantages over living cells, including the ability to modify the secretome composition to achieve specific therapeutic goals. This study describes for the first time a procedure for obtaining equine mesenchymal stem cell secretomes using two distinct methods and conducts a comparative study of their biological activity in an in vitro wound model. Using ToupView 3.7 software, the wound width was measured in photographs at each of six points for each well after 0 hours of incubation (immediately after the scratch) and 24 hours of incubation. The average "scratch" width was calculated at 0:00 and 24:00. The ratio of the average "scratch" width after 24 hours of incubation to the average "scratch" width after 0:00 was then calculated. The wound closure rate relative to "K" was then calculated for each sample. The result was expressed as a percentage relative to the control. For the first time, the stability of the biological activity of the MSC secretome was assessed during storage at temperatures ranging from +4 to +8°C for two months. Based on the results of these studies, a promising candidate MSC secretome will be selected for further testing: first in laboratory animals to assess safety using various routes of administration, and then in horses to analyze its effects on cardiovascular and respiratory parameters in pathological conditions both at rest and after exercise.

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