The Effect of the Cultivation Conditions of Mesenchymal Stem Cells on Their Viability upon Being Transplanted into the Subretinal Space

Abstract

The use of mesenchymal stem cells is an effective treatment strategy for a number of retinal degenerative diseases. The poor survival of these cells after transplantation is the limiting factor of this approach. It was shown previously that the cultivation of mesenchymal stem cells under hypoxia can increase their proliferative activity. We assumed that this method of cultivation will improve the viability of these cells after their transplantation into the subretinal space. To this end, we isolated mesenchymal stem cells from the red bone marrow of mice, characterized their phenotype, their ability to differentiate in the chondrogenic, osteogenic, and adipogenic directions, as well as their proliferative activity after cultivation under hypoxia (5% oxygen in the atmosphere) and normoxia (21% oxygen in the atmosphere). Red bone marrow cells were obtained in the same way from C57 Black mice carrying the GFP gene. These cells were loaded with magnetic microparticles after preliminary cultivation under normoxia (the control) and hypoxia (the experiment) and injected subretinally to rabbits. The cells were held at the injection site using a magnetic implant that prevented their migration. Cell survival was evaluated on the 3rd, 5th, 9th, 12th, and 15th days using fluorescence microscopy and optical coherence tomography. According to the obtained data, the cells grown under hypoxic conditions remained viable in the subretinal space for 9 days, while the cells that grew under normoxia conditions died after 6 days. Thus, pre-cultivation of mesenchymal stem cells under hypoxic conditions can increase their viability after transplantation into the subretinal space, which can be used in the treatment of degenerative diseases of the retina.