CRYO PRESERVATION OF HUMAN DENDRITIC CELLS FOR CLINICAL USE

. The increasing clinical use of cellular technologies suggests the possibility of long-term storage of the cellular product while maintaining its viability and basic properties. The procedures of cell’s cryopreservation used in laboratory as well in clinical practice differ a lot. Each method includes two tasks to solve: what is the optimal freezing medium to use and what cryopreservation procedure to prefer. In this paper, we present the method utilized in our center for bone marrow cell cryopreservation. The freezing was carried out in nitrogen vapor after adding the medium containing 95 % dextran [average mw 50 000–70 000] and 5 % dimethylsulfoxid. Purpose. To show that the proposed method of cryopreservation of dendritic cells is highly effective, simple, reproducible and most convenient for clinical use. Materials and methods . Viability, expression of surface antigens and stimulating activity towards allogeneic T lymphocytes of cryopreserved mature dendritic cells cultured from peripheral blood monocytes were evaluated. Results. The first cryopreservation resulted in the death of a small amount of cells. The second freezing procedure increased the proportion of dead cells. Meanwhile, the difference in the expression of the surface antigens in fresh, cryopreserved and re-cryopreserved dendritic cells was not statistically significant. The level of stimulating activity of fresh and cryopreserved dendritic cells did not significantly differ. Conversely the proliferation of allogeneic T lymphocytes was decreased after stimulation with re-cryopreserved dendritic cells. Conclusion . The presented method of cryopreservation allows to preserve the viability and basic functions of dendritic cells. After thawing dendritic vaccine could be administered to patients after being diluted in an isotonic saline without washing, which makes this method the most convenient for clinical use.