Use of human albumin as an additional cryoprotective agent in freeze preservation of hematopoietic stem cells

: 14 bone-marrow samples of healthy donors were cryopreserved with 5% of DMSO in combination with different volume percentages of 20% human albumin, with the protective impact of the respective freezing mixture on the proliferating capacity of early hemotopoietic precursor cells being determined by means of CFU-c-technique. A combination of 5% of DMSO with 20% of human albumin with an addition of 20% of autologous serum proved to be the most favourable freezing protection. CFU-c-recovery which was achieved in this way amounted to 78 +/- 7%. A protective impact of human albumin for CFU-c during incubation with the freezing medium at room temperature was statistically not significant. Thus, the method presented is suitable for cryopreservation of bone marrow for autologous transplantation. The advantages over the traditional procedure results from the slight degree of toxicity by reducing the DMSO percentage from the common 10% to 5% as well as from the fact that the thawed cell suspension may be directly infused with the substance for freezing protection, thus avoiding an additional loss of proliferative material. The procedure may be used especially for autologous transplantation in childhood.