[Influence of cryopreservation on leukemic dendritic cells derived from leukemia patients].

This study was aimed to investigate the influence of cryopreservation on biological properties and function of leukemic dendritic cells (L-DCs) derived from patients with acute or chronic leukemia. Some fresh leukemic cells were detected immediately; some were cultured immediately; some were cryopreserved in -80 degrees C with 5% DMSO-6% HES as cryopreservor. After being thawed, they were cultured. The combination of rhGM-CSF, rhIL-4, rhTNF-alpha and other cytokines were added into the culture system. 12 days later, L-DCs were assayed for morphology, immunophenotype, mixed lymphocytic reaction (MLR) and CTL cytotoxicity on autologous leukemic cells. The results showed that both fresh and cryopreserved leukemic cells obtained from patients with acute or chronic leukemia revealed typical DC morphologically by means of using combinations of cytokines in culture, but there was no significant difference between pre-or post cryopreservations. L-DCs also upregulated the expression of CD80, CD54, HLA-DR, CD1a, CD83 and CD86, and downregulated the expression of CD14, but there was also no difference as compared with L-DCs befor cryopreservation. L-DCs derived from leukemic cells were also capable of stimulating MLR and inducing CTL which could kill autologous leukemic cells obviously. It is concluded that leukemic cells, regardless of fresh or frozen, can induce L-DCs after culture with cytokine combination. The L-DCs can induce CTL targeting autologous leukemic cells, and may be used to treat MRD as immunotherapy. The induction and biological properties of L-DCs are not influenced by cryopreservation.