INTRODUCTION: The question of efficient preservation of cells, especially Mesenchymal stem cells (MSC) becomes more and more urgent due to the impetuous development of cell therapy in clinics. There are two main problems in the improvement of mixtures used for cells cryopreservation. First is the application of DMSO as cryoprotectant, which is known to cause different side effects, and the second is the necessity to exclude xenogeneic materials. So, the aim of this work was to minimize DMSO concentration in cryo-freeze mixture and to change fetal bovine serum (FBS) usually used in laboratories for allogeneic materials.
METHODS:MSC were isolated from human umbilical cord (UC) using explant method. After obtaining of 2nd passage, cells were frozen in different mixtures that contained from 1% to 10 % of DMSO and different additives, including trehalose, ethylene glycol and sucrose. To avoid xenogeneic material FBS was replaced with platelet lysate obtained from human plate concentrate with triple freezing. The result was evaluated by comparison of cell survival after de-freezing in one month, cell morphology and their potential for multiplication.
RESULTS: It has been shown that the best mixture for cell cryopreservation with reduced concentration of DMSO is 4% DMSO, 6% trehalose and 90%FBS. In this variant the survival rate was 94,3±0,2 compared to 95,9±0,1 in control variant with 10% DMSO. MSC morphology and growth potential were also similar. Study of the possibility to use platelet lysate instead of FBS confirmed the ability of the lysate to support cells during cryoconcervation, but this work requires more long observation as store time should be extended.
CONCLUSION: The data obtained showed that cryopreservation of MSC in the cryo-freeze mixture with a reduced concentration of DMSO provides a high survival rate of cells, does not change their biological and morphological properties. FBS in the mixture for MSC cryopreservation can be replaced by human platelet lysate.