Comparison of Hematopoietic Stem Cell Containing Fractions between Cryopreserved-thawed Cord Blood and Mobilized Peripheral Blood / 대한소아혈액종양학회지

ABSTRACT

PURPOSE: Discordance with expectation there are a few differences in hematopoietic stem cells according to their source. The purpose of this study is to compare the cryopreservative potential of hematopoiectic stem cell containing fractions between cord blood (CB) and mobilized peripheral blood (mPB) during long term cryopreservation. METHODS: Nineteen CB and seven mPB were frozen with a programed freezer and stored in liquid phase of nitrogen from 1 to 4 years. After thawing the viability of mononuclear cells (MNCs) and the recovery rate of MNC, CD34 positive cell, colony form unit-granulocyte/monocyte was measured by CD34 flow cytometry and colony formation in semisolid methycellulose culture. CD34 positive cell was purified from cryopreserved-thawed or fresh mPB using magnetic associated cell sorting (MACS) CD34 selection kit. RESULTS: Though there is no difference in the viability and the recovery rate of CFU-GM between cryopreserved-thawed CB and mPB, the recovery rate of MNCs and CD34 positive cells is much higher in CB. Cell aggregation during the thawing process of long term cryopreserved mPB was effectively prevented by using high viscosity thawing buffer like as 10% dextran and 20% human serum albumin. We can also purify the CD34 positive cells from the long term cryopreserved mPB in the purity of more than 90%. CONCLUSION: Contrary to mPB long term cryopreserved CB can maintain the hematopoietic stem cell fraction without considerable loss, so it can be clinically used for hematopoietic stem cell transplantation.