lipid-a and Leukemia--Myeloid--Acute

Generation of monocyte-derived dendritic cells (MDDC) is induced in the presence of GM-CSF and IL-4, and a maturation stimulus is added to the monocyte culture to obtain mature Dendritic Cells (DCs) suitable for therapy. TNF-α is the most common cytokine used for activating DCs and generating mature MDDC either alone or in combination with other cytokines.. To compare effects of traditional cytokine cocktail (TNF-α + IL-1β) versus TLR4-agonist monophosphoryl lipid A on the viability, phenotype, cytokine profile and functionality of MDDC.. The study included 32 individuals; twenty Acute Myeloid Leukaemia (AML) cases in complete remission and 12 healthy volunteers. They were divided into 3 groups: Group 1: control group: 12 subjects to measure the baseline levels of all markers in the monocytic preparation. Group 2: cytokine cocktail (TNF-α) group, which included 10 AML subjects. Group 3: MPLA group which included 10 AML subjects.. TNF-α group showed higher expression of CD83 than MPLA group indicating higher capacity to induce DC maturation but both were similar in CD86, CCR7 and IL-10 expression. Preparation of dendritic cells from AML cases in remission and loading them with tumor peptides was successful.. MPLA effect in DC maturation is comparable with traditional DC maturation cocktail.

Topics: Antigens, Neoplasm; B7-2 Antigen; Cell Differentiation; Cells, Cultured; Dendritic Cells; Humans; Immunotherapy, Adoptive; Interleukin-10; Interleukin-1beta; Leukemia, Myeloid, Acute; Lipid A; Peptide Fragments; Receptors, CCR7; Toll-Like Receptor 4; Tumor Necrosis Factor-alpha

Leukemic cells in the myeloblastic stage from a murine myeloid leukemia cell line (M1) were induced to differentiate to macrophages by lipopolysaccharide (LPS) from Gram-negative bacteria. A granulocyte-macrophage colony-stimulating factor (CSF) was produced only during differentiation. After induction of differentiation, the continued presence of LPS was necessary to stimulate the macrophages to release CSF. In contrast, a macrophage cell line (Mm-1) derived from the M1 line produced CSF without LPS-stimulation, but CSF release was stimulated by the presence of LPS.

Topics: Animals; Cell Differentiation; Cells, Cultured; Colony-Stimulating Factors; Granulocytes; Leukemia, Myeloid, Acute; Lipid A; Lipopolysaccharides; Macrophages; Mice; Mice, Inbred C57BL

Normal myeloid and MGI(+)D(+) clones of myeloid leukemic cells can be induced for Fc and complement component 3 rosettes, lysozme, and mature macrophages and granulocytes by a protein with macrophage- and granulocyte-inducing (MGI) activity, whereas MGI(+)D(-) clones can be induced by this protein for rosettes and lysozme but not mature cells. Lipopolysaccharides (LPS) from different bacteria induced the appearance of rosettes, lysozyme, and macrophages in some MGI(+)D(+) clones but did not induce any of these changes in MGI(+)D(-) clones. Lipid A gave the same results as LPS. Incubation of MGI(+)D(+) cells with LPS also induced an MGI activity detectable in the culture medium. This activity behaved like MGI in inducing (i) rosettes, lysozyme, and mature cells in MGI(+)D(+) leukemic cells including a clone resistant to LPS, (ii) rosettes and lysozyme in MGI(+)D(-) leukemic cells, and (iii) differentiation of normal myeloid cells to mature macrophages and granulocytes. This activity was induced in MGI(+)D(+) cells by LPS before the induction of rosettes or lysozyme. The results indicate that the lipid A portion of LPS indirectly induces differentiation of MGI(+)D(+) myeloid leukemic cells by inducing MGI protein. It is suggested that induction of specific regulatory proteins may be a more general mechanism for the induction of differentiation by surface-acting compounds.

Topics: Animals; Binding Sites; Cell Differentiation; Complement C3; Growth Substances; Immunoglobulin Fc Fragments; Leukemia, Experimental; Leukemia, Myeloid, Acute; Lipid A; Lipopolysaccharides; Macrophages; Muramidase; Species Specificity