The observation of the effect of different cell concentration on peripheral blood stem cells (PBSC) cryopreservation under -80℃

Objective To observe the effect of cell concentration on peripheral blood stem cells (PBSC) cryopreservation under -80℃. Methods Under -80℃ with protective agent which final density was 5%DMSO, 3%HES, 4%HAS, PBSC were cryopreserved at cell concentration recommended (1.3 3.9)×10 7/ml),cell concentration adjusted (8.0 29.9)×10 7/ml) and high cell concentration (30.1 70.1)×10 7/ml).After thawing, the cell viability including the number of MNC and the recovery of CFU GM and CD34 + cells were measured at the different time (1,3,6,9,12 months after cryopreservation). Results Cell viability had no significant decline within 12months in each group. The recovery of MNC,CFU GM and CD34 + cells at cell concentration recommended, cell concentration adjusted and high cell concentration was above 80% respectively in 9 months, which were no significantly decreased( P 0.05), compared with those in 1 month; There was no significant difference in the recovery of MNC,CFU GM and CD34 + cells among cell concentration recommended , cell concentration adjusted and high cell concentration of PBSC cryopreserved at the same time. It is enough to make sure that the PBSC transplantation be successful by cryopreservation of PBSC in -80℃ freezer with different cell concentration. Conclusion It was suggested that, the cryopreservation method of PBSC in -80℃ freezer with 5%DMSO, 3%HES, 4%HSA as its protective agent be effective to the different cell concentration. The concentration of cell suspension to be cryopreserved may be raised appropriately and the total volume decreased properly in order to alleviate the clinical side reaction.