Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P05231 (interleukin-6)
 23,907 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Normal murine bone marrow (BM) cells were sorted on the basis of low forward and orthogonal light scatter properties, Sca-1 expression (Sca-1+), lack of staining with a cocktail of mature hematopoietic lineage markers (Lin-), and binding of wheat germ agglutinin (WGA+). This approach allowed the reproducible isolation of a very small subpopulation (0.037% +/- 0.023% of all nucleated BM cells) that was approximately 400-fold enriched in cells capable of reconstituting both lymphoid and myeloid lineages in lethally irradiated recipients. Transplantation of 30 or 10 of these Sca-1+Lin-WGA+ cells resulted in > or = to 20% donor-derived nucleated peripheral blood cells 3 months posttransplantation in 100% and 22% of the recipients, respectively. When Sca-1+Lin-WGA+ cells were cultured in serum-free medium supplemented with Steel factor, interleukin-6 (IL-6), and erythropoietin (with or without IL-3), a large increase in total cell number, including cells with an Sca-1+Lin-WGA+ phenotype was observed. Single cell cultures showed that 90% to 95% of the input cells underwent at least one division during the first 2 weeks and the remainder died. Interestingly, this proliferative response was not accompanied by a parallel increase in the number of cells with both lymphoid and myeloid repopulating potential in vivo, as quantitation of these by limiting dilution analysis showed they had decreased slightly (1.3-fold) but not significantly below the number initially present. These results demonstrate that Sca-1+Lin-WGA+ cells with long-term repopulating potential can be maintained for 2 weeks in a serum- and stroma cell-free culture, providing a simple in vitro system to study their behavior under well-defined conditions. The observed expansion of Sca-1+Lin-WGA+ cells in vitro without a concomitant increase in reconstituting cells also shows that extensive functional heterogeneity exists within populations of cells with this surface phenotype.
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PMID:Amplification of Sca-1+ Lin- WGA+ cells in serum-free cultures containing steel factor, interleukin-6, and erythropoietin with maintenance of cells with long-term in vivo reconstituting potential. 750 75

Multilineage differentiation of human fetal bone marrow CD34+ cell subsets was examined using a single-cell liquid culture assay. Four CD34+ cell populations, ie, (1) CD38-, HLA-DR+, (2) CD38-, HLA-DR-, (3) CD38+, HLA-DR-, and (4) CD38+, HLA-DR+ cells, were sorted as single cells into 96-well flat-bottom culture plates containing long-term culture medium supplemented with interleukin-3, interleukin-6, stem cell factor (SCF), granulocyte-macrophage colony-stimulating factor, erythropoietin, basic fibroblast growth factor (bFGF), and insulin-like growth factor-1 (IGF-1). Single CD34+, CD38-, HLA-DR+ cells had the highest replating efficiency as well as the highest replating efficiency. The cellular composition of the single-cell progeny was studied by morphologic and/or flow cytometric examination. Only the progeny of single CD34+ cells that lacked CD38 could give rise to each of the hematopoietic cell lineages. The expansion of the progeny of single CD34+, CD38-, HLA-DR+ cells was examined in more detail and showed three clearly distinguishable growth patterns: 28% (SD, +/- 10%; n = 14) of the single cells formed cell clusters/colonies; 9% (SD, +/- 4%; n = 14) formed dispersed cells; and 11% (SD, +/- 6%; n = 14) gave rise to a mixture of cell clusters and dispersed cells. The dispersed cell growth pattern was reduced when SCF or bFGF and IGF-1 was absent in the growth factor cocktail. The replating ability of the dispersed cells was considerably larger than that of cells with other growth patterns, in that 76% of the cells that gave rise to dispersed cells and 54% of the cells that gave rise to dispersed cells as well as cell clusters gave rise to a second generation, but only 7% of the cells that gave rise to cell clusters gave rise to a second generation. The second generation of cells continued to produce third and fourth generations after repetitive replating, except for the replated cells from cell clusters. In contrast with the first-generation progeny, SCF did not have an influence on the replating ability of the cells. Only in the progeny of single CD34+, CD38-, HLA-DR+ cells that gave rise to dispersed cells was each of the hematopoietic cell lineages found, ie, B lymphocytes, neutrophils, monocytes, macrophages, osteoclasts, basophils/mast cells, eosinophils, erythrocytes, megakaryocytes, and platelets.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Lymphoid and myeloid differentiation of single human CD34+, HLA-DR+, CD38- hematopoietic stem cells. 751 Jan 44

We have previously shown that the most primitive human hematopoietic cells are included within a cell subpopulation expressing high levels of CD34 and low or undetectable levels of CD45RA and CD71. In this study, cord blood cells with this phenotype were sorted and further separated based on their expression on the Thy-1 antigen. The proliferation and differentiation of the purified cell fractions in response to a mixture of hematopoietic cytokines was analyzed in serum- and stroma-free liquid cultures. Thy-1+ cells (25% of CD34+ CD45RAlo CD71lo cells) were particularly enriched for high proliferative potential colony-forming cells (HPP-CFC; up to 45% of the clonogenic cells), whereas Thy-1- cells were enriched for multipotential colony-forming cells (CFU-MIX; up to 46% of the clonogenic cells). When both subpopulations were cultured in serum-free liquid cultures supplemented with a cytokine mixture that included steel factor, interleukin-6 (IL-6), granulocyte-macrophage colony-stimulating factor (GM-CSF)/IL-3 fusion protein, M-CSF, G-CSF, and erythropoietin, Thy-1+ cells showed a much higher numerical expansion of CD34+ cells (30,000-fold) and colony-forming cells (4,700-fold) than was observed in cultures initiated with Thy-1- cells (900-fold increase in CD34+ cell numbers and 241-fold increase in CFC numbers). Cells coexpressing CD34 and Thy-1 were only transiently expanded (up to 29-fold) and were not detected after day 22 of culture. When CD34+ CD45RAlo CD71lo Thy-1+ cells were cultured, either in semi-solid or liquid cultures, in the presence of anti-Thy-1 antibody, a significant reduction in progenitor cell numbers (particularly HPP-CFC) was observed. In contrast, CD34+ CD45RAlo CD71lo Thy-1- cells were not affected by anti-Thy-1. The results of this study indicate that Thy-1 is expressed on primitive cord blood progenitors with the highest in vitro proliferative potential, and further suggest that Thy-1 is involved in hematopoietic cell development, possibly by mediating a negative signal that results in inhibition of primitive cell proliferation.
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PMID:Thy-1 expression is linked to functional properties of primitive hematopoietic progenitor cells from human umbilical cord blood. 751 97

Colony-stimulating factors (CSFs) are proteins that play normal roles in human hematopoietic physiology. Many of these factors have been cloned and sequences. This has led to recombinant DNA technology that now allows for production of large quantities of pharmacologically pure compounds. Granulocyte colony-stimulating factor (G-CSF) and granulocyte-macrophage colony-stimulating factor (GM-CSF) are two such compounds that have been approved by the US Food and Drug Administration for human use in specific medical circumstances. This article summarizes the experience of one institution in using these two CSFs and adds brief commentary on four other CSFs that are expected to come to general use in the near future--interleukin-1, interleukin-3, interleukin-6, and erythropoietin. Both G-CSF and GM-CSF are effective in protecting patients from the leukotoxic effects of cancer chemotherapy, but GM-CSF appears to have a comparatively narrow "dosing window," wherein the agent is effective and tolerable. Future studies should address combining these agents with platelet protective compounds to improve patient safety.
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PMID:The use of colony-stimulating factors as bone marrow support for systemic anticancer chemotherapy. 752 98

Cytokines and growth factors elicit responses in target cells through induction of gene expression. Signaling mechanisms leading to gene transcription from cell surface receptors often require tyrosine phosphorylation. A family of transcription factors comprising the interferon (IFN)-stimulated gene factor 3 (ISGF3) multimeric complex are phosphorylated and activated in response to interferon. We describe a protein 50% identical to the 91-kDa subunit of ISGF3 that constitutes the acute phase response factor (APRF). This protein was rapidly activated by interleukin-6 to bind an enhancer element common to genes activated in liver cells during the acute phase response to inflammation. Remarkably, APRF was also activated by IFN alpha, IFN gamma, epidermal growth factor, platelet-derived growth factor, colony stimulating factor-1, and the cytokines leukemia inhibitory factor and oncostatin M. The growth factors also activated a third, distinct but related, DNA-binding protein in addition to APRF and p91. This novel factor or a closely related one, but neither APRF nor p91, was also activated in lymphoid cells by interleukin-2, erythropoietin, and interleukin-3. Activation of APRF, p91, and additional members of the ISGF3 family is thus a general feature of a wide variety of signaling pathways, integrating diverse signals through common transcriptional regulators.
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PMID:Acute phase response factor and additional members of the interferon-stimulated gene factor 3 family integrate diverse signals from cytokines, interferons, and growth factors. 752 73

Multiple cycles of high-dose chemotherapy can be hematologically supported by repeated administration of peripheral blood progenitors obtained after mobilization using cytokine alone or in combination with chemotherapy. We have explored the quality of such cells and their potential to undergo ex vivo expansion. Twenty-five leukapheresis samples from 19 patients who had received extensive prior chemotherapy for stage IV breast cancer were subjected to CD34+ cell selection using immunoaffinity columns of immunomagnetic bead separation. Cells were cultured in suspension in the presence of c-kit ligand, interleukin-3, interleukin-6, erythropoietin, and granulocyte colony-stimulating factor. Ten experiments were performed using weekly exchange of media and cytokines (Delta assay). Median myeloid and erythroid progenitors expanded 15-fold at 7 days (range, 7 to 43), 40-fold at 14 days (range, 18 to 470), 46-fold at 21 days (range, 0 to 118), and 21-fold at 28 days (range, 0 to 61). In a system using gas-permeable bags without exchange of media or cytokine, median progenitors expanded 13-fold at 7 days (range, 7 to 36), 14-fold at 10 days (range, 4 to 61), 14-fold at 12 days (range, 3 to 46), and 10-fold at 14 days (range, 1 to 35). Progenitor expansion less than 10-fold occurred in 8% of experiments at day 7, in 17% at day 10, in 43% at day 12, and in 50% at day 14. When autologous plasma, autologous plasma processed (removal of cryoprecipitate, centrifugation, then filtration), or human serum were substituted for 20% fetal calf serum, the ratio of progenitor expansion at 7 days relative to 20% fetal calf serum for 10% human serum, 20% human serum, and 1% autologous plasma processed was 1.01 (range, 0.62 to 1.33), 0.88 (range, 0.61 to 1.20), and 0.96 (range, 0.55 to 1.64), respectively. These findings support the feasibility of ex vivo expansion in a system free of nonhuman proteins of CD34(+)-derived progenitors obtained from the peripheral blood of patients who have received prior chemotherapy.
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PMID:Optimization of conditions for ex vivo expansion of CD34+ cells from patients with stage IV breast cancer. 752 42

The use of the recombinant hematopoietic growth factors G-CSF and GM-CSF have shortened the period of neutropenia, or avoided this problem, in many cancer patients who have received cytotoxic therapy. Although these benefits have been particularly striking in the autologous bone marrow and/or autologous peripheral blood progenitor cell transplant setting, most data suggest that the use of G-CSF and GM-CSF only marginally enhance recovery of the neutrophil count when administered after allogeneic bone marrow infusion. Furthermore, in the allograft setting these expensive agents have not provided benefit in the form of enhanced platelet count recovery, lessening the incidence of graft-versus-host disease, or improvement in overall survival. These data do not justify routine widespread use of G-CSF and GM-CSF and suggest that these agents should be reserved for patients who experience delay in engraftment after allogeneic bone marrow infusion. Administration of erythropoietin, on the other hand, may reduce the need for homologous red blood cell transfusions, and may increase the safety margin for both the allogeneic bone marrow recipient and as well as the donor. Recombinant hematopoietic growth factors targetted specifically to enhance platelet recovery after transplantation (such as interleukin-3, interleukin-6, and interleukin-11) have shown promise after autotransplantation and after conventional dose chemotherapy, and likely will be evaluated in the allogeneic transplant patient.
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PMID:Clinical use of hematopoietic growth factors in allogeneic bone marrow transplantation. 752 6

We have previously shown that early human CD34high hematopoietic progenitors are maintained quiescent in part through autocrine transforming growth factor-beta 1 (TGF-beta 1). We also demonstrated that, in the presence of interleukin-3, interleukin-6, granulocyte colony-stimulating factor, and erythropoietin, TGF-beta 1 antisense oligonucleotides or anti-TGF-beta serum have an additive effect with KIT ligand (Steel factor [SF]), which suggests that they control different pathways of regulation in these conditions. This finding also suggests that autocrine TGF-beta 1 might suppress c-kit expression in primitive human hematopoietic progenitors. We have now distinguished two subpopulations of CD34high cells. One subpopulation expresses a c-kit mRNA that can be downmodulated by exogenous TGF-beta 1 within 6 hours. Another subpopulation of early CD34high cells expresses a low or undetectable level of c-kit mRNA, but its expression can be upmodulated within 6 hours by anti-TGF-beta. These effects disappear 48 hours after induction and cannot be maintained longer than 72 hours, even if TGF-beta 1 or anti-TGF-beta serum are added every day. Similar kinetics, although delayed, are observed with KIT protein expression. On the contrary, no specific effect of TGF-beta 1 was observed on c-fms, GAPDH, and transferrin receptor gene expression in these early progenitors. These results clarify the complex interaction between TGF-beta 1 and SF in normal early hematopoietic progenitors. SF does not switch off the TGF-beta 1 inhibitory pathway. Autocrine TGF-beta 1 appears to maintain these cells in a quiescent state, suppressing cell division by downmodulating the receptor of SF, a key cytokine costimulator of early progenitors.
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PMID:Early CD34high cells can be separated into KIThigh cells in which transforming growth factor-beta (TGF-beta) downmodulates c-kit and KITlow cells in which anti-TGF-beta upmodulates c-kit. 754 39

Previously, it was believed that megakaryocytopoiesis was regulated by two types of humoral factors: megakaryocyte colony-stimulating factor (MK-CSF), which acts on progenitors inducing their proliferation, and thrombopoietin (TPO), a megakaryocyte(s) (MK) maturational factor that induces platelet formation. The recently cloned Mpl-ligand (Mpl-L) seems to have both properties in vivo and in vitro and has also been called TPO. However, it cannot be excluded that a part of these activities is due to a synergistic effect with growth factors present in the serum or synthesized by accessory cells. To delineate the precise TPO (Mpl-L) biologic activities, we performed serum-free cultures at limiting cell dilution. Target cells were adult human marrow CD34+CD41+ cells, which represent a highly selected population of late MK progenitor or transitional cells. Cells were purified using a flow cytometer equipped with an automatic cloning design unit. We determined that the recombinant molecule had a biologic activity that reached a plateau at 10 ng/mL. At this concentration, a linear relationship between the average MK number per well and the number of cells seeded (between 1 to 50 cells per well) was observed. At one cell per well, 60% of the wells contained a single MK at day 5 of culture. Half of these wells contained only one large MK, whereas the other half contained several MK (up to 25), demonstrating that TPO has direct proliferative biologic activity. In contrast, at limiting dilution, none of the other cytokines tested (stem cell factor [SCF], interleukin-6 [IL-6], and erythropoietin [Epo]) were effective, whereas IL-3 showed a mild effect. However, a combination of SCF plus IL-6 plus IL-3 produced similar results as TPO alone. Addition of the other cytokines to TPO did not enhance the cloning efficiency of the CD34+CD41+ cells but increased twofold the average number of MKs per clone. MKs reached a ploidy of 32N and 64N in the presence of TPO. The mean ploidy value was approximately 6 and was not modified by addition of the other cytokines. At the ultrastructural level, a majority of the MKs showed maturational defects related to an imbalance between the synthesis of alpha-granules and demarcation membranes. However, a fraction (about 30%) had a cytoplasmic maturation that exactly mimicked that of marrow MKs. In addition, proplatelet-shedding MKs were observed in the cultures, even at limiting dilution. Such a result was not observed with any other individual cytokines, including the combination of three cytokines.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:The Mpl-ligand or thrombopoietin or megakaryocyte growth and differentiative factor has both direct proliferative and differentiative activities on human megakaryocyte progenitors. 754 60

A new human multilineage myeloid leukemia cell line, MHH225, has been established in our laboratory from the bone marrow of a 60-year-old patient suffering from acute megakaryoblastic leukemia (M7); it provides a unique model for studying the effect of biologic and chemical agents on the lineage specificity of a multipotent myeloid leukemia clone containing a mixed population of megakaryoblast, erythroblast, and myeloblast cells in a serum-free culture. Morphologically, all 225 cells are large blast cells with basophilic cytoplasm containing no granules, large round nucleus containing 2-3 prominent nucleoli, and fine chromatin structure and a large nuclear/cytoplasm ratio. The MHH225 cells are CD34+HLA-DR+CD33+CD13+ with 57.6%, 28.3%, and 7.8% of them being CD41+, glycophorin A+, and CD15+, respectively, and all lymphoid-specific antigens are negative. The karyotype analysis of MHH225 cells revealed a deletion of the short arm of chromosome 7: del(7)(p13)-, a whole-arm translocation between the long arms of chromosomes 9 and 21: t(9;21)(q10;q10), and a chromosome 11 with an elongated long arm due to duplication of chromosome 11 material as well as to translocation of part of chromosome 9 onto 11q+. Also, chromosome 21 was deleted in some metaphases or showed a ring formation in other metaphases. Utrastructurally, MHH25 cells display a strong platelet peroxidase activity in the nuclear envelope and the endoplasmic reticulum. The MHH25 cells have been grown exponentially without growth factors or conditioned media or serum only in RPMI1640 culture medium. None of the myelopoietic growth factors, i.e., interleukin-3, GM-CSF, G-CSF, erythropoietin, or interleukin-6, has any effect on the proliferation and differentiation of MHH25 cells. The two, hematopoietic inhibitory cytokines, interferon-alpha and tumor necrosis factor-alpha, have only minimal growth inhibitory effect. Stem cell factor showed only weak growth-stimulatory effect on MHH225 cells but significantly inhibited chemotherapy-induced apoptosis in these cells. The new cell line MHH225 should constitute a useful model for studying stem cell antigen (CD34)-positive human multilineage myeloid leukemia cells carrying a deletion in the short arm of chromosome 7 and an aberration in chromosome 11 and provide a unique tool for investigating human hematopoietic stem cell biology and its cytokine regulation in serum-free cultures. To our knowledge, the MHH225 cell line is the first human CD34-positive leukemia cell line growing in serum-free cultures to be established.
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PMID:Establishment and characterization of a novel CD34-positive human myeloid leukemia cell line: MHH225 growing in serum-free culture. 754 28


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