A hypothermal storage solution for cytokine-induced killer cells derived from cord blood

We measured the killing activities of cytokine-induced killer cells (CIK) cells after hypothermal storage of such cells to identify an effective freezing solution. Fourteen days after induction of CIK cells from cultured umbilical cord blood, cells were frozen and stored in a new storage solution (10% [v/v] dimethyl sulphoxide [DMSO]; 10% [w/v] Dextran; and lymphocytes, but without serum) and traditional cell freezing solution (15% [v/v] DMSO; 10% [w/v] human albumin; and lymphocytes, also without serum). Cells were thawed and cultured after 180 days, and cell morphology and proliferation were investigated. Flow cytometric measurement (FCM) was used to define the immune phenotype. The lactate dehydrogenas (LDH) method was employed to test the ability of stored and freshly induced CIK cells to kill The myelogenous leukemia cell line K562. The morphologies and immune phenotypes of freshly induced and stored (in either solution) cells were similar. The proliferative activity and killing capacity of fresh CIK cells and those stored in the new solution were similar, and higher than those of cells stored in the traditional solution.