Dendritic Cells Derived In Vitro From Acute Myeloid Leukemia Cells That Induce Anti-leukemia-specific T Cell Immune Response

Objectives:To explore the feasibility of dendritic cells (DC) being in vitro induced from acute myeloid leukemia (AML) cells with 3 different cytokine cocktails, the biological properties of AML-derived DCs and whether AML-derived DCs can induce anti-leukemia-specific T cell immune response.Methods:T cell-depleted bone marrow or peripheral blood mononuclear cells from 21 patients with AML were cultured in either presence of cytokine cocktails granulocyte-macrophage colony-stimulating factor (GM-CSF) + interleukin-4 (IL-4), GM-CSF + tumor necrosis factor-α (TNF-α), GM-CSF + IL-4 + TNF-α or absence of cytokines. Morphologies and viability of cultured AML cells were examined every day under phase contrast microscopy. The viability of cultured AML cells was also evaluated by Trypan blue exclusion. Cytospin specimens of cultured AML cells were studied by cytochemical staining. Immunophenotyping of uncultured and cultured AML cells were conducted through indirect or direct immunofluorescent staining. Standard 5-day one-way mixed leukocyte culture (MLC) assay examined the allostimulatory abilities of uncultured and cultured AML cells. Fluorescein isothiocyanate-conjugated dextran (FITC-DX) uptake test examined the fluid phase macromolecule uptake function of cultured AML cells. For generation of cytotoxic T lymphocyte (CTL) to the target cells, the uncultured or cultured AML cells were co-cultured with pre-activated auto-T lymphocytes from untreated patients or patients in complete remissions by anti-CD3 monoclonal antibody in the presence of low-dose IL-2 for 7 days. Cytotoxicities were determined with lactate dehydrogenase release. The unstimulated, IL-2 alone-stimulated, uncultured or cultured AML cells-stimulated T cells were...