ovalbumin and Leukemia--Myeloid

Co-transplantation of hematopoietic stem cells with those engineered to express leukemia-reactive T-cell receptors (TCRs) and differentiated ex vivo into precursor T cells (preTs) may reduce the risk of leukemia relapse. As expression of potentially self-(leukemia-) reactive TCRs will lead to negative selection or provoke autoimmunity upon thymic maturation, we investigated a novel concept whereby TCR expression set under the control of an inducible promoter would allow timely controlled TCR expression. After in vivo maturation and gene induction, preTs developed potent anti-leukemia effects. Engineered preTs provided protection even after repeated leukemia challenges by giving rise to effector and central memory cells. Importantly, adoptive transfer of TCR-transduced allogeneic preTs mediated anti-leukemia effect without evoking graft-versus-host disease (GVHD). Earlier transgene induction forced CD8(+) T-cell development was required to obtain a mature T-cell subset of targeted specificity, allowed engineered T cells to efficiently pass positive selection and abrogated the endogenous T-cell repertoire. Later induction favored CD4 differentiation and failed to produce a leukemia-reactive population emphasizing the dominant role of positive selection. Taken together, we provide new functional insights for the employment of TCR-engineered precursor cells as a controllable immunotherapeutic modality with significant anti-leukemia activity.

Topics: Adoptive Transfer; Animals; Flow Cytometry; Genetic Engineering; Graft vs Host Disease; Graft vs Leukemia Effect; Hematopoietic Stem Cell Transplantation; Humans; Leukemia, Myeloid; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Mice, Transgenic; Ovalbumin; Precursor Cells, T-Lymphoid; Promoter Regions, Genetic; Receptors, Antigen, T-Cell; Transplantation, Homologous

The aim of the present study is to investigate the effects of Vam3 which is one of the dihydroxystilbene compounds on expressions of ICAM-1 in the lungs of OVA-induced asthmatic mice and the mechanisms of anti-airway inflammation. Balb/c mice were challenged with OVA inhalation. Lung tissues were stained with Mayer's hematoxylin and eosin for histopathologic examination. The expression of ICAM-1 in the lungs of mice was analyzed by Western blotting and immunohistochemistry method. The NF-kappaB activities were detected by NF-kappaB-luc reporter genetic transient transfection method. The activities of MMP-9 induced by LPS, TNF-alpha and PMA in THP-1 cells were determined by gelatin zymography method. The results showed that Vam3 could inhibit the expression of ICAM-1 in the OVA-induced mouse model. In addition, Vam3 could significantly suppress the activities of NF-kappaB in A549 cells and MMP-9 in THP-1 cells induced by LPS, TNF-alpha and PMA. These results suggested that Vam3 could alleviate the asthmatic inflammation by decreasing ICAM-1 expression in asthmatic mice, down regulating NF-kappaB and MMP-9 activities. Compound Vam3 showed inhibitory effects on inflammatory signal pathways involved in asthma.

Topics: Animals; Anti-Asthmatic Agents; Anti-Inflammatory Agents; Asthma; Benzofurans; Cell Line, Tumor; Humans; Inflammation; Intercellular Adhesion Molecule-1; Leukemia, Myeloid; Lung; Lung Neoplasms; Male; Matrix Metalloproteinase 9; Mice; Mice, Inbred BALB C; NF-kappa B; Ovalbumin; Stilbenes

Defects in apoptosis mechanisms contribute to chemoresistance in malignancy. However, correlations of apoptosis-regulating proteins with clinical outcome in cancer patients are variable, presumably reflecting the difficulty of using static tests of gene expression in a scenario influenced by a dynamic interplay of multiple pro- and antiapoptotic molecules. Therefore, we assessed the functional integrity of apoptosis pathways in intact primary leukemia cells and correlated the functional status of these pathways with clinical outcome. Active apoptogenic proteins were introduced into primary leukemia cells by electroporation followed by measurement of active caspases by flow cytometric techniques. Cytochrome c was introduced to activate the intrinsic (mitochondrial) pathway, whereas caspase-8 was introduced to activate the extrinsic (death receptor) pathway. In a series of 24 patients with acute myeloid leukemia, 79% had a block in at least one pathway, indicating that defects in caspase activation mechanisms are common in patients with leukemia. Simultaneous blocks in both pathways correlated with chemoresistant disease (92% of patients with chemoresistant disease versus 33% of patients with chemosensitive disease; P = 0.005) and decreased overall patient survival (35% versus 89% 1-year survival; P = 0.02). Simultaneous blockage of the intrinsic and extrinsic pathways could be explained by a defect located at a point of convergence of the two pathways, probably related to overexpression of endogenous inhibitors of the effector-caspases, rather than decreased levels of these proteases. This study supports the importance of apoptosis pathways in determining response to chemotherapy and suggests that functional defects in caspase activation are prognostic in patients with leukemia.

Topics: Adult; Aged; Caspase 3; Caspase 8; Caspase 9; Caspase Inhibitors; Caspases; Cytochrome c Group; Drug Resistance, Neoplasm; Electroporation; Enzyme Activation; Granzymes; Humans; K562 Cells; Leukemia, Myeloid; Middle Aged; Mitochondria; Ovalbumin; Serine Endopeptidases

The use of antigen-presenting dendritic cells (DCs) is currently proposed for tumor immunotherapy through generation of CTLs to tumor antigens in cancer patients. In this study, DCs were differentiated using granulocyte-macrophage colony-stimulating factor and tumor necrosis factor-alpha from CD34+ hematopoietic progenitor cells that had been mobilized into the peripheral blood. To use the phagocytic activity of DCs for processing and presentation of tumor antigens, we established DC clusters containing immature DCs by preserving proliferating cell clusters without mechanical disruption. After an 11-day culture, the developed clusters contained not only typical mature DCs but also immature DCs that showed active phagocytosis of latex particles, suggesting that the clusters consisted of DCs of different maturational stages. These heterogeneous clusters could present an exogenous protein antigen, keyhold limpet hemocyanin, to both CD4+ and CD8+ T lymphocytes. Furthermore, in three acute myelogeneous leukemia patients, clusters pulsed with autologous irradiated leukemic cells could also induce antileukemic CTLs. The mechanical disruption of clusters abrogated the induction of CTLs to leukemic cells as well as to hemocyanin. This observation gives an important information for the use of heterogeneous DC clusters derived from autologous peripheral blood CD34+ cells in the case of immunotherapy for leukemia.

Topics: Acute Disease; Antigen Presentation; Antigens, CD34; Antigens, Neoplasm; CD4-Positive T-Lymphocytes; CD8-Positive T-Lymphocytes; Cell Adhesion; Cells, Cultured; Dendritic Cells; Hematopoietic Stem Cells; Hemocyanins; Humans; Immunotherapy; Leukemia, Myeloid; Lymphocyte Culture Test, Mixed; Neoplastic Stem Cells; Ovalbumin; Phagocytosis; Stress, Mechanical; T-Lymphocytes, Cytotoxic

Regulation of in-vivo differentiation of myeloid leukemic cells by response to antigen was analysed with different clones of mouse myeloid leukemic cells and human myeloid leukemic cells (HL-60). Differentiation was studied in diffusion chambers implanted into the peritoneal cavity of mice and the antigens used were bovine serum albumin and chicken ovalbumin. It is shown that the presence of either of these antigens in the diffusion chambers can induce differentiation in MGI+D+ mouse and human myeloid leukemic cells, and that pre-immunization with antigen enhanced this in-vivo differentiation. This enhancement showed immunological specificity and was transferred from immunized to non-immunized mice by spleen cells enriched for T lymphocytes. In contrast to these results with MGI+D+ clones of myeloid leukemic cells, clones of WEHI-3B myeloid leukemic cells were induced to differentiate in vivo to the same extent either in the presence or absence of antigen. The results indicate: that in-vivo differentiation of MGI+D+ clones of myeloid leukemic cells can be induced by response to antigen and that in-vivo differentiation of different clones of myeloid leukemic cells can be regulated in different ways.

Topics: Animals; Antigens; Cell Differentiation; Cells, Cultured; Humans; Immunization, Passive; Leukemia, Myeloid; Mice; Mice, Inbred ICR; Ovalbumin; Serum Albumin, Bovine

Topics: Binding Sites; Chromatography, Ion Exchange; Glucosamine; Glycosides; Humans; Hydrogen-Ion Concentration; Leukemia, Myeloid; Muramidase; Ovalbumin; Protein Binding; Spectrometry, Fluorescence