Role of mesenchymal stromal cells and their secretory products in kidney regeneration

Kidney diseases are an important medical problem. Kidney injuries are accompanied by oxidative stress, cell death, capillary destruction, inflammation and fibrosis. Mesenchymal stromal cells (MSCs) have a complex effect on the regeneration by producing various regulatory molecules, including those inside extracellular vesicles, and therefore are considered as a promising therapeutic resource for cell therapy of kidney diseases. Their renoprotective effect has been shown in different experimental models, but the results of the clinical trials are ambiguous. Clinical use of MSCs is complicated by their low survival rate in the injured kidney, potential immunogenicity, tumorogenicity and fibrogenicity. Cell-free therapy with the secretory products of MSCs such as conditioned environments or extracellular vesicles is a promising direction for using their regenerative potential. However, introduction of MSCs and their secretory products into medical practice requires further research into the mechanisms of their proregenerative action, improvement of cultivation protocols, and more clinical trials.