Outlook of Adipose-Derived Stem Cells: Challenges to Their Clinical Application in Horses

SIMPLE SUMMARY: Athletic horses are often exposed to traumatic injuries, resulting in severe financial losses. Adipose tissue possesses a high potential as an easily accessible source and provides a higher yield of mesenchymal stem cells for various applications in regenerative medicine. Concerning the identification of the stemness features of isolated cells, some of the most commonly applied standards are not applicable because of the species-specific responses to the differentiation protocols. In many cases, the cells cannot reveal their multipotent properties, so their stemness features remain questionable. The adaptation, optimization, and standardization of equine-specific protocols for cell isolation and culture conditions are also discussed. The presented new approaches elucidate the possibility of the transition from cell-based to cell-free therapy with regenerative purposes in horses as an alternative treatment to cellular therapy. The current review summarizes aspects of the specificity of equine adipose stem cells concerning their features, immunophenotyping, secretome profile, differentiation abilities, culturing conditions, and consequent possibilities for clinical application in some equine-specific disorders. ABSTRACT: Adipose tissue is recognized as the major endocrine organ, potentially acting as a source of mesenchymal stem cells for various applications in regenerative medicine. Athletic horses are often exposed to traumatic injuries, resulting in severe financial losses. The development of adipose-derived stem cells’ regenerative potential depends on many factors. The extraction of stem cells from subcutaneous adipose tissue is non-invasive, non-traumatic, cheaper, and safer than other sources. Since there is a lack of unique standards for identification, the isolated cells and applied differentiation protocols are often not species-specific; therefore, the cells cannot reveal their multipotent properties, so their stemness features remain questionable. The current review discusses some aspects of the specificity of equine adipose stem cells concerning their features, immunophenotyping, secretome profile, differentiation abilities, culturing conditions, and consequent possibilities for clinical application in concrete disorders. The presented new approaches elucidate the possibility of the transition from cell-based to cell-free therapy with regenerative purposes in horses as an alternative treatment to cellular therapy. In conclusion, their clinical benefits should not be underestimated due to the higher yield and the physiological properties of adipose-derived stem cells that facilitate the healing and tissue regeneration process and the ability to amplify the effects of traditional treatments. More profound studies are necessary to apply these innovative approaches when treating traumatic disorders in racing horses.