Tarusin D. Hypothermic storage and cryopreservation of mesenchymal stromal cells in alginate microspheres.

The research object was cryopreservation and storage at positive temperatures of mesenchymal stromal cells (MSCs) encapsulated in alginate microspheres (AMS) using electrospray. The research aim was to determine the effect of cryopreservation and storage at positive temperatures on the properties of MSCs encapsulated in AMS using electrospray. The research methods were as follows: monolayer and three-dimensional cultivation in vitro; obtaining AMS using electrospray; programmed freezing; volumetry; physical and mathematical modeling; spectrophotometry; fluorescence spectroscopy; light and fluorescence microscopy; morphometric analysis; statistical analysis of results. It was found that MSCs encapsulated in AMS using electrospray retained high viability and functional activity in culture. It was established at first that MSCs in AMS were characterized by a reversible decrease in metabolic activity and membrane potential of mitochondria. Based on osmotic reaction of the MSCs in AMS in the presence of 1 M DMSO solution and using mathematical modeling firstly there were theoretically determined the parameters of the effective regime for cryopreservation, its effectiveness was confirmed experimentally. The new results are relative to the fact that encapsulation in AMS promotes preservation of the MSCs at positive temperatures 22 and 37 °C during storage in the culture medium based on α-MEM for 3 days. The data are new relative to the fact that the use of specialized solutions for hypothermic storage provides high preservation of the MSCs in AMS when they incubated at 4 °C, and also enables to extend preservation time of up to 7 days.