Quantification and cytokine production of circulating lymphoid and myeloid cells in acute myelogenous leukaemia

Abstract

A simple assay was developed to assess the potential of patients with acute myelogenous leukaemia (AML) to respond to immunotherapy. Lymphocytes, monocytes and leukaemic blasts with their corresponding intracellular cytokine profiles were evaluated by four-colour flow cytometry. In 50 ll samples of whole blood, surface labelling for CD45, CD8 and CD3 was used for cell identification prior to intracellular staining for interleukin (IL)-4, IL-10, IL-12 and interferon (IFN)-c. Absolute numbers of CD8 + and CD8 À (putative CD4 + ) T-cells, NK cells (CD8 + /CD3 À ) and monocytes were determined by reference to a fixed number of added fluorescent beads. The absolute numbers of CD8 À and CD8 + T-cells in the blood of patients with AML were similar to those of normal controls. More of the lymphocytes in the blood of leukaemic patients spontaneously produced cytokines compared with those of controls. Furthermore, primary AML blasts secreted predominantly IFN-c. After recovery from chemotherapy, lymphocyte counts tended to be lower than in normals and reduction of NK cells reached significance after the second chemotherapy (P ¼ 0.01). A prominent CD8 lo /CD3 lo-int lymphocyte subset appeared after recovery in some patients. This laboratory application of the study of cell subsets and intracellular cytokines in patients undergoing treatment may be helpful in monitoring immunological responses in AML.

Cytosine arabinoside induces costimulatory molecule expression in acute myeloid leukemia cells

“…AML cells naturally secrete interferon-g and IL-12 and it seems possible, at least in some cases, to differentiate blast cells in vitro into dendritic cells able to stimulate Induced costimulatory molecules by Ara-C in AML R Vereecque et al autologous CTL expansion, with specific activity against AML cells. [29][30][31][32][33][34] Expansion of specific CTL has also been reported using nonleukemic dendritic cells. 35 However, the optimal schedule to reinject these expanded CTL remained to be defined.…”

Peripheral blood T cells in acute myeloid leukemia (AML) patients at diagnosis have abnormal phenotype and genotype and form defective immune synapses with AML blasts

“…Only 2 previous studies have addressed the issue of absolute T-cell numbers in the PB at the time of diagnosis with AML. 17,18 We report here our findings characterizing T cells in PB of newly diagnosed AML patients compared with age-matched healthy controls. Surprisingly, we report that the absolute number of PB T cells in AML patients is increased, as are CD3 ϩ 56 ϩ cells.…”

Innate immune-induced depletion of bone marrow neutrophils aggravates systemic bacterial infections

“…Dihydrorhodamine 123 (DHR, Sigma) was used for measuring NADPH oxidase activity by measuring cellular fluorescence in FL1 channel (emission 534 nm). A fixed number of fluoroescent APC beads were used to measure cell number per sample volume and have been described before (31). ␣-GR1 (NimpR14) hybridoma was a generous gift from Tacchini-Cottier (Epalinges, Switzerland) (20).…”