Granulocyte-Macrophage Colony-Stimulating Factor: An acidic glycoprotein of MW 23 kDa with internal disulfide bonds. The protein is produced in response to a number of inflammatory mediators by mesenchymal cells present in the hemopoietic environment and at peripheral sites of inflammation. GM-CSF is able to stimulate the production of neutrophilic granulocytes, macrophages, and mixed granulocyte-macrophage colonies from bone marrow cells and can stimulate the formation of eosinophil colonies from fetal liver progenitor cells. GM-CSF can also stimulate some functional activities in mature granulocytes and macrophages.Granulocyte Colony-Stimulating Factor: A glycoprotein of MW 25 kDa containing internal disulfide bonds. It induces the survival, proliferation, and differentiation of neutrophilic granulocyte precursor cells and functionally activates mature blood neutrophils. Among the family of colony-stimulating factors, G-CSF is the most potent inducer of terminal differentiation to granulocytes and macrophages of leukemic myeloid cell lines.Colony-Stimulating Factors: Glycoproteins found in a subfraction of normal mammalian plasma and urine. They stimulate the proliferation of bone marrow cells in agar cultures and the formation of colonies of granulocytes and/or macrophages. The factors include INTERLEUKIN-3; (IL-3); GRANULOCYTE COLONY-STIMULATING FACTOR; (G-CSF); MACROPHAGE COLONY-STIMULATING FACTOR; (M-CSF); and GRANULOCYTE-MACROPHAGE COLONY-STIMULATING FACTOR; (GM-CSF).Macrophage Colony-Stimulating Factor: A mononuclear phagocyte colony-stimulating factor (M-CSF) synthesized by mesenchymal cells. The compound stimulates the survival, proliferation, and differentiation of hematopoietic cells of the monocyte-macrophage series. M-CSF is a disulfide-bonded glycoprotein dimer with a MW of 70 kDa. It binds to a specific high affinity receptor (RECEPTOR, MACROPHAGE COLONY-STIMULATING FACTOR).Receptors, Granulocyte Colony-Stimulating Factor: Receptors that bind and internalize GRANULOCYTE COLONY-STIMULATING FACTOR. Their MW is believed to be 150 kD. These receptors are found mainly on a subset of myelomonocytic cells.Receptor, Macrophage Colony-Stimulating Factor: A receptor for MACROPHAGE COLONY-STIMULATING FACTOR encoded by the c-fms proto-oncogene (GENES, FMS). It contains an intrinsic protein-tyrosine kinase activity. When activated the receptor undergoes autophosphorylation, phosphorylation of down-stream signaling molecules and rapid down-regulation.Receptors, Granulocyte-Macrophage Colony-Stimulating Factor: Receptors that bind and internalize the granulocyte-macrophage stimulating factor. Their MW is believed to be 84 kD. The most mature myelomonocytic cells, specifically human neutrophils, macrophages, and eosinophils, express the highest number of affinity receptors for this growth factor.Interleukin-3: A multilineage cell growth factor secreted by LYMPHOCYTES; EPITHELIAL CELLS; and ASTROCYTES which stimulates clonal proliferation and differentiation of various types of blood and tissue cells.Receptors, Colony-Stimulating Factor: Cell surface receptors for colony stimulating factors, local mediators, and hormones that regulate the survival, proliferation, and differentiation of hemopoietic cells.Recombinant Proteins: Proteins prepared by recombinant DNA technology.Hematopoietic Stem Cells: Progenitor cells from which all blood cells derive.Granulocytes: Leukocytes with abundant granules in the cytoplasm. They are divided into three groups according to the staining properties of the granules: neutrophilic, eosinophilic, and basophilic. Mature granulocytes are the NEUTROPHILS; EOSINOPHILS; and BASOPHILS.Hematopoiesis: The development and formation of various types of BLOOD CELLS. Hematopoiesis can take place in the BONE MARROW (medullary) or outside the bone marrow (HEMATOPOIESIS, EXTRAMEDULLARY).Bone Marrow Cells: Cells contained in the bone marrow including fat cells (see ADIPOCYTES); STROMAL CELLS; MEGAKARYOCYTES; and the immediate precursors of most blood cells.Growth Substances: Signal molecules that are involved in the control of cell growth and differentiation.Colony-Forming Units Assay: A cytologic technique for measuring the functional capacity of stem cells by assaying their activity.Bone Marrow: The soft tissue filling the cavities of bones. Bone marrow exists in two types, yellow and red. Yellow marrow is found in the large cavities of large bones and consists mostly of fat cells and a few primitive blood cells. Red marrow is a hematopoietic tissue and is the site of production of erythrocytes and granular leukocytes. Bone marrow is made up of a framework of connective tissue containing branching fibers with the frame being filled with marrow cells.Neutropenia: A decrease in the number of NEUTROPHILS found in the blood.Neutrophils: Granular leukocytes having a nucleus with three to five lobes connected by slender threads of chromatin, and cytoplasm containing fine inconspicuous granules and stainable by neutral dyes.Leukocyte Count: The number of WHITE BLOOD CELLS per unit volume in venous BLOOD. A differential leukocyte count measures the relative numbers of the different types of white cells.Macrophages: The relatively long-lived phagocytic cell of mammalian tissues that are derived from blood MONOCYTES. Main types are PERITONEAL MACROPHAGES; ALVEOLAR MACROPHAGES; HISTIOCYTES; KUPFFER CELLS of the liver; and OSTEOCLASTS. They may further differentiate within chronic inflammatory lesions to EPITHELIOID CELLS or may fuse to form FOREIGN BODY GIANT CELLS or LANGHANS GIANT CELLS. (from The Dictionary of Cell Biology, Lackie and Dow, 3rd ed.)Hematopoietic Stem Cell Mobilization: The release of stem cells from the bone marrow into the peripheral blood circulation for the purpose of leukapheresis, prior to stem cell transplantation. Hematopoietic growth factors or chemotherapeutic agents often are used to stimulate the mobilization.Cells, Cultured: Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.Receptors, Interleukin-3: High affinity receptors for INTERLEUKIN-3. They are found on early HEMATOPOIETIC PROGENITOR CELLS; progenitors of MYELOID CELLS; EOSINOPHILS; and BASOPHILS. Interleukin-3 receptors are formed by the dimerization of the INTERLEUKIN-3 RECEPTOR ALPHA SUBUNIT and the CYTOKINE RECEPTOR COMMON BETA SUBUNIT.Cell Division: The fission of a CELL. It includes CYTOKINESIS, when the CYTOPLASM of a cell is divided, and CELL NUCLEUS DIVISION.Monocytes: Large, phagocytic mononuclear leukocytes produced in the vertebrate BONE MARROW and released into the BLOOD; contain a large, oval or somewhat indented nucleus surrounded by voluminous cytoplasm and numerous organelles.Stem Cell Factor: A hematopoietic growth factor and the ligand of the cell surface c-kit protein (PROTO-ONCOGENE PROTEINS C-KIT). It is expressed during embryogenesis and is a growth factor for a number of cell types including the MAST CELLS and the MELANOCYTES in addition to the HEMATOPOIETIC STEM CELLS.Hematopoietic Cell Growth Factors: These growth factors comprise a family of hematopoietic regulators with biological specificities defined by their ability to support proliferation and differentiation of blood cells of different lineages. ERYTHROPOIETIN and the COLONY-STIMULATING FACTORS belong to this family. Some of these factors have been studied and used in the treatment of chemotherapy-induced neutropenia, myelodysplastic syndromes, and bone marrow failure syndromes.Cytokines: Non-antibody proteins secreted by inflammatory leukocytes and some non-leukocytic cells, that act as intercellular mediators. They differ from classical hormones in that they are produced by a number of tissue or cell types rather than by specialized glands. They generally act locally in a paracrine or autocrine rather than endocrine manner.Cell Differentiation: Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.Antigens, CD34: Glycoproteins found on immature hematopoietic cells and endothelial cells. They are the only molecules to date whose expression within the blood system is restricted to a small number of progenitor cells in the bone marrow.Genes, fms: Family of genes originally isolated from the Susan McDonough strain of feline sarcoma virus (SARCOMA VIRUSES, FELINE). The proto-oncogene fms (c-fms) codes for the MCSF receptor (RECEPTOR, MACROPHAGE COLONY-STIMULATING FACTOR). The oncogene fms (v-fms) codes for ONCOGENE PROTEIN GP140(V-FMS) which is a mutated form of the MCSF. The human c-fms gene is located between 5q33.2 and 5q33.3.Osteopetrosis: Excessive formation of dense trabecular bone leading to pathological fractures; OSTEITIS; SPLENOMEGALY with infarct; ANEMIA; and extramedullary hemopoiesis (HEMATOPOIESIS, EXTRAMEDULLARY).Cell Line: Established cell cultures that have the potential to propagate indefinitely.RNA, Messenger: RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.Leukemia, Myeloid: Form of leukemia characterized by an uncontrolled proliferation of the myeloid lineage and their precursors (MYELOID PROGENITOR CELLS) in the bone marrow and other sites.Leukapheresis: The preparation of leukocyte concentrates with the return of red cells and leukocyte-poor plasma to the donor.Cyclophosphamide: Precursor of an alkylating nitrogen mustard antineoplastic and immunosuppressive agent that must be activated in the LIVER to form the active aldophosphamide. It has been used in the treatment of LYMPHOMA and LEUKEMIA. Its side effect, ALOPECIA, has been used for defleecing sheep. Cyclophosphamide may also cause sterility, birth defects, mutations, and cancer.Interleukin-1: A soluble factor produced by MONOCYTES; MACROPHAGES, and other cells which activates T-lymphocytes and potentiates their response to mitogens or antigens. Interleukin-1 is a general term refers to either of the two distinct proteins, INTERLEUKIN-1ALPHA and INTERLEUKIN-1BETA. The biological effects of IL-1 include the ability to replace macrophage requirements for T-cell activation.Mice, Inbred C57BLReceptors, Interleukin-5: Cell surface receptors that are specific for INTERLEUKIN-5. They are heterodimeric proteins consisting of the INTERLEUKIN-5 RECEPTOR ALPHA SUBUNIT and the CYTOKINE RECEPTOR COMMON BETA SUBUNIT. Signaling from interleukin-5 receptors can occur through interaction of their cytoplasmic domains with SYNTENINS.Tumor Necrosis Factor-alpha: Serum glycoprotein produced by activated MACROPHAGES and other mammalian MONONUCLEAR LEUKOCYTES. It has necrotizing activity against tumor cell lines and increases ability to reject tumor transplants. Also known as TNF-alpha, it is only 30% homologous to TNF-beta (LYMPHOTOXIN), but they share TNF RECEPTORS.Interleukin-6: A cytokine that stimulates the growth and differentiation of B-LYMPHOCYTES and is also a growth factor for HYBRIDOMAS and plasmacytomas. It is produced by many different cells including T-LYMPHOCYTES; MONOCYTES; and FIBROBLASTS.Interleukin-5: A cytokine that promotes differentiation and activation of EOSINOPHILS. It also triggers activated B-LYMPHOCYTES to differentiate into IMMUNOGLOBULIN-secreting cells.Agranulocytosis: A decrease in the number of GRANULOCYTES; (BASOPHILS; EOSINOPHILS; and NEUTROPHILS).Antigens, CD: Differentiation antigens residing on mammalian leukocytes. CD stands for cluster of differentiation, which refers to groups of monoclonal antibodies that show similar reactivity with certain subpopulations of antigens of a particular lineage or differentiation stage. The subpopulations of antigens are also known by the same CD designation.Flow Cytometry: Technique using an instrument system for making, processing, and displaying one or more measurements on individual cells obtained from a cell suspension. Cells are usually stained with one or more fluorescent dyes specific to cell components of interest, e.g., DNA, and fluorescence of each cell is measured as it rapidly transverses the excitation beam (laser or mercury arc lamp). Fluorescence provides a quantitative measure of various biochemical and biophysical properties of the cell, as well as a basis for cell sorting. Other measurable optical parameters include light absorption and light scattering, the latter being applicable to the measurement of cell size, shape, density, granularity, and stain uptake.Antineoplastic Combined Chemotherapy Protocols: The use of two or more chemicals simultaneously or sequentially in the drug therapy of neoplasms. The drugs need not be in the same dosage form.Tumor Cells, Cultured: Cells grown in vitro from neoplastic tissue. If they can be established as a TUMOR CELL LINE, they can be propagated in cell culture indefinitely.Injections, Subcutaneous: Forceful administration under the skin of liquid medication, nutrient, or other fluid through a hollow needle piercing the skin.Blood Cell Count: The number of LEUKOCYTES and ERYTHROCYTES per unit volume in a sample of venous BLOOD. A complete blood count (CBC) also includes measurement of the HEMOGLOBIN; HEMATOCRIT; and ERYTHROCYTE INDICES.Mice, Inbred BALB CDendritic Cells: Specialized cells of the hematopoietic system that have branch-like extensions. They are found throughout the lymphatic system, and in non-lymphoid tissues such as SKIN and the epithelia of the intestinal, respiratory, and reproductive tracts. They trap and process ANTIGENS, and present them to T-CELLS, thereby stimulating CELL-MEDIATED IMMUNITY. They are different from the non-hematopoietic FOLLICULAR DENDRITIC CELLS, which have a similar morphology and immune system function, but with respect to humoral immunity (ANTIBODY PRODUCTION).Erythropoietin: Glycoprotein hormone, secreted chiefly by the KIDNEY in the adult and the LIVER in the FETUS, that acts on erythroid stem cells of the BONE MARROW to stimulate proliferation and differentiation.Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.Drug Synergism: The action of a drug in promoting or enhancing the effectiveness of another drug.Eosinophils: Granular leukocytes with a nucleus that usually has two lobes connected by a slender thread of chromatin, and cytoplasm containing coarse, round granules that are uniform in size and stainable by eosin.Pulmonary Alveolar Proteinosis: A PULMONARY ALVEOLI-filling disease, characterized by dense phospholipoproteinaceous deposits in the alveoli, cough, and DYSPNEA. This disease is often related to, congenital or acquired, impaired processing of PULMONARY SURFACTANTS by alveolar macrophages, a process dependent on GRANULOCYTE-MACROPHAGE COLONY-STIMULATING FACTOR.Dose-Response Relationship, Drug: The relationship between the dose of an administered drug and the response of the organism to the drug.Leukocytosis: A transient increase in the number of leukocytes in a body fluid.Platelet Count: The number of PLATELETS per unit volume in a sample of venous BLOOD.Signal Transduction: The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.Leukemia, Myeloid, Acute: Clonal expansion of myeloid blasts in bone marrow, blood, and other tissue. Myeloid leukemias develop from changes in cells that normally produce NEUTROPHILS; BASOPHILS; EOSINOPHILS; and MONOCYTES.Hematopoietic Stem Cell Transplantation: Transfer of HEMATOPOIETIC STEM CELLS from BONE MARROW or BLOOD between individuals within the same species (TRANSPLANTATION, HOMOLOGOUS) or transfer within the same individual (TRANSPLANTATION, AUTOLOGOUS). Hematopoietic stem cell transplantation has been used as an alternative to BONE MARROW TRANSPLANTATION in the treatment of a variety of neoplasms.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Mice, Inbred C3HGene Expression Regulation: Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control (induction or repression) of gene action at the level of transcription or translation.Interleukin-4: A soluble factor produced by activated T-LYMPHOCYTES that induces the expression of MHC CLASS II GENES and FC RECEPTORS on B-LYMPHOCYTES and causes their proliferation and differentiation. It also acts on T-lymphocytes, MAST CELLS, and several other hematopoietic lineage cells.T-Lymphocytes: Lymphocytes responsible for cell-mediated immunity. Two types have been identified - cytotoxic (T-LYMPHOCYTES, CYTOTOXIC) and helper T-lymphocytes (T-LYMPHOCYTES, HELPER-INDUCER). They are formed when lymphocytes circulate through the THYMUS GLAND and differentiate to thymocytes. When exposed to an antigen, they divide rapidly and produce large numbers of new T cells sensitized to that antigen.Spleen: An encapsulated lymphatic organ through which venous blood filters.Cytokine Receptor Common beta Subunit: A receptor subunit that is a shared component of the INTERLEUKIN-3 RECEPTOR; the INTERLEUKIN-5 RECEPTOR; and the GM-CSF RECEPTOR. High affinity receptor complexes are formed with each of these receptors when their respective alpha subunits are combined with this shared beta subunit.Interferon-gamma: The major interferon produced by mitogenically or antigenically stimulated LYMPHOCYTES. It is structurally different from TYPE I INTERFERON and its major activity is immunoregulation. It has been implicated in the expression of CLASS II HISTOCOMPATIBILITY ANTIGENS in cells that do not normally produce them, leading to AUTOIMMUNE DISEASES.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Blood Component Removal: Any procedure in which blood is withdrawn from a donor, a portion is separated and retained and the remainder is returned to the donor.Osteoclasts: A large multinuclear cell associated with the BONE RESORPTION. An odontoclast, also called cementoclast, is cytomorphologically the same as an osteoclast and is involved in CEMENTUM resorption.Bone Marrow Transplantation: The transference of BONE MARROW from one human or animal to another for a variety of purposes including HEMATOPOIETIC STEM CELL TRANSPLANTATION or MESENCHYMAL STEM CELL TRANSPLANTATION.Proto-Oncogene Proteins: Products of proto-oncogenes. Normally they do not have oncogenic or transforming properties, but are involved in the regulation or differentiation of cell growth. They often have protein kinase activity.Gene Expression: The phenotypic manifestation of a gene or genes by the processes of GENETIC TRANSCRIPTION and GENETIC TRANSLATION.Leukemia, Megakaryoblastic, Acute: An acute myeloid leukemia in which 20-30% of the bone marrow or peripheral blood cells are of megakaryocyte lineage. MYELOFIBROSIS or increased bone marrow RETICULIN is common.LeukopeniaMegakaryocytes: Very large BONE MARROW CELLS which release mature BLOOD PLATELETS.Bone Marrow DiseasesCancer Vaccines: Vaccines or candidate vaccines designed to prevent or treat cancer. Vaccines are produced using the patient's own whole tumor cells as the source of antigens, or using tumor-specific antigens, often recombinantly produced.Immunophenotyping: Process of classifying cells of the immune system based on structural and functional differences. The process is commonly used to analyze and sort T-lymphocytes into subsets based on CD antigens by the technique of flow cytometry.Kinetics: The rate dynamics in chemical or physical systems.Drug Administration Schedule: Time schedule for administration of a drug in order to achieve optimum effectiveness and convenience.Etoposide: A semisynthetic derivative of PODOPHYLLOTOXIN that exhibits antitumor activity. Etoposide inhibits DNA synthesis by forming a complex with topoisomerase II and DNA. This complex induces breaks in double stranded DNA and prevents repair by topoisomerase II binding. Accumulated breaks in DNA prevent entry into the mitotic phase of cell division, and lead to cell death. Etoposide acts primarily in the G2 and S phases of the cell cycle.Transplantation, Autologous: Transplantation of an individual's own tissue from one site to another site.Lipopolysaccharides: Lipid-containing polysaccharides which are endotoxins and important group-specific antigens. They are often derived from the cell wall of gram-negative bacteria and induce immunoglobulin secretion. The lipopolysaccharide molecule consists of three parts: LIPID A, core polysaccharide, and O-specific chains (O ANTIGENS). When derived from Escherichia coli, lipopolysaccharides serve as polyclonal B-cell mitogens commonly used in laboratory immunology. (From Dorland, 28th ed)Transfection: The uptake of naked or purified DNA by CELLS, usually meaning the process as it occurs in eukaryotic cells. It is analogous to bacterial transformation (TRANSFORMATION, BACTERIAL) and both are routinely employed in GENE TRANSFER TECHNIQUES.Myelopoiesis: Formation of MYELOID CELLS from the pluripotent HEMATOPOIETIC STEM CELLS in the BONE MARROW via MYELOID STEM CELLS. Myelopoiesis generally refers to the production of leukocytes in blood, such as MONOCYTES and GRANULOCYTES. This process also produces precursor cells for MACROPHAGE and DENDRITIC CELLS found in the lymphoid tissue.Thrombocytopenia: A subnormal level of BLOOD PLATELETS.Doxorubicin: Antineoplastic antibiotic obtained from Streptomyces peucetius. It is a hydroxy derivative of DAUNORUBICIN.Treatment Outcome: Evaluation undertaken to assess the results or consequences of management and procedures used in combating disease in order to determine the efficacy, effectiveness, safety, and practicability of these interventions in individual cases or series.Interleukin-2: A soluble substance elaborated by antigen- or mitogen-stimulated T-LYMPHOCYTES which induces DNA synthesis in naive lymphocytes.Lymphoma, Non-Hodgkin: Any of a group of malignant tumors of lymphoid tissue that differ from HODGKIN DISEASE, being more heterogeneous with respect to malignant cell lineage, clinical course, prognosis, and therapy. The only common feature among these tumors is the absence of giant REED-STERNBERG CELLS, a characteristic of Hodgkin's disease.N-Formylmethionine Leucyl-Phenylalanine: A formylated tripeptide originally isolated from bacterial filtrates that is positively chemotactic to polymorphonuclear leucocytes, and causes them to release lysosomal enzymes and become metabolically activated.Leukemia, Myelomonocytic, Chronic: A myelodysplastic-myeloproliferative disease characterized by monocytosis, increased monocytes in the bone marrow, variable degrees of dysplasia, but an absence of immature granulocytes in the blood.Receptors, Interleukin: Cell surface proteins that bind interleukins and trigger intracellular changes influencing the behavior of cells.Recombinant Fusion Proteins: Recombinant proteins produced by the GENETIC TRANSLATION of fused genes formed by the combination of NUCLEIC ACID REGULATORY SEQUENCES of one or more genes with the protein coding sequences of one or more genes.Cell Count: The number of CELLS of a specific kind, usually measured per unit volume or area of sample.Antibodies, Monoclonal: Antibodies produced by a single clone of cells.Cell Survival: The span of viability of a cell characterized by the capacity to perform certain functions such as metabolism, growth, reproduction, some form of responsiveness, and adaptability.Interleukins: Soluble factors which stimulate growth-related activities of leukocytes as well as other cell types. They enhance cell proliferation and differentiation, DNA synthesis, secretion of other biologically active molecules and responses to immune and inflammatory stimuli.Leukopoiesis: The process of generating white blood cells (LEUKOCYTES) from the pluripotent HEMATOPOIETIC STEM CELLS of the BONE MARROW. There are two significant pathways to generate various types of leukocytes: MYELOPOIESIS, in which leukocytes in the blood are derived from MYELOID STEM CELLS, and LYMPHOPOIESIS, in which leukocytes of the lymphatic system (LYMPHOCYTES) are generated from lymphoid stem cells.Receptors, Cell Surface: Cell surface proteins that bind signalling molecules external to the cell with high affinity and convert this extracellular event into one or more intracellular signals that alter the behavior of the target cell (From Alberts, Molecular Biology of the Cell, 2nd ed, pp693-5). Cell surface receptors, unlike enzymes, do not chemically alter their ligands.Leukemia, Myelomonocytic, Acute: A pediatric acute myeloid leukemia involving both myeloid and monocytoid precursors. At least 20% of non-erythroid cells are of monocytic origin.Anemia, Aplastic: A form of anemia in which the bone marrow fails to produce adequate numbers of peripheral blood elements.Culture Media: Any liquid or solid preparation made specifically for the growth, storage, or transport of microorganisms or other types of cells. The variety of media that exist allow for the culturing of specific microorganisms and cell types, such as differential media, selective media, test media, and defined media. Solid media consist of liquid media that have been solidified with an agent such as AGAR or GELATIN.Protein-Tyrosine Kinases: Protein kinases that catalyze the PHOSPHORYLATION of TYROSINE residues in proteins with ATP or other nucleotides as phosphate donors.Cell SeparationLeukocytes, Mononuclear: Mature LYMPHOCYTES and MONOCYTES transported by the blood to the body's extravascular space. They are morphologically distinguishable from mature granulocytic leukocytes by their large, non-lobed nuclei and lack of coarse, heavily stained cytoplasmic granules.Clone Cells: A group of genetically identical cells all descended from a single common ancestral cell by mitosis in eukaryotes or by binary fission in prokaryotes. Clone cells also include populations of recombinant DNA molecules all carrying the same inserted sequence. (From King & Stansfield, Dictionary of Genetics, 4th ed)Myelodysplastic Syndromes: Clonal hematopoietic stem cell disorders characterized by dysplasia in one or more hematopoietic cell lineages. They predominantly affect patients over 60, are considered preleukemic conditions, and have high probability of transformation into ACUTE MYELOID LEUKEMIA.Macrophage Activation: The process of altering the morphology and functional activity of macrophages so that they become avidly phagocytic. It is initiated by lymphokines, such as the macrophage activation factor (MAF) and the macrophage migration-inhibitory factor (MMIF), immune complexes, C3b, and various peptides, polysaccharides, and immunologic adjuvants.Thrombopoietin: A humoral factor that stimulates the production of thrombocytes (BLOOD PLATELETS). Thrombopoietin stimulates the proliferation of bone marrow MEGAKARYOCYTES and their release of blood platelets. The process is called THROMBOPOIESIS.Mice, Inbred Strains: Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations, or by parent x offspring matings carried out with certain restrictions. All animals within an inbred strain trace back to a common ancestor in the twentieth generation.Janus Kinase 2: A Janus kinase subtype that is involved in signaling from GROWTH HORMONE RECEPTORS; PROLACTIN RECEPTORS; and a variety of CYTOKINE RECEPTORS such as ERYTHROPOIETIN RECEPTORS and INTERLEUKIN RECEPTORS. Dysregulation of Janus kinase 2 due to GENETIC TRANSLOCATIONS have been associated with a variety of MYELOPROLIFERATIVE DISORDERS.Myeloid Progenitor Cells: Stem cells derived from HEMATOPOIETIC STEM CELLS. Derived from these myeloid progenitor cells are the MEGAKARYOCYTES; ERYTHROID CELLS; MYELOID CELLS; and some DENDRITIC CELLS.Cytarabine: A pyrimidine nucleoside analog that is used mainly in the treatment of leukemia, especially acute non-lymphoblastic leukemia. Cytarabine is an antimetabolite antineoplastic agent that inhibits the synthesis of DNA. Its actions are specific for the S phase of the cell cycle. It also has antiviral and immunosuppressant properties. (From Martindale, The Extra Pharmacopoeia, 30th ed, p472)Tetradecanoylphorbol Acetate: A phorbol ester found in CROTON OIL with very effective tumor promoting activity. It stimulates the synthesis of both DNA and RNA.Interleukin-8: A member of the CXC chemokine family that plays a role in the regulation of the acute inflammatory response. It is secreted by variety of cell types and induces CHEMOTAXIS of NEUTROPHILS and other inflammatory cells.Whole-Body Irradiation: Irradiation of the whole body with ionizing or non-ionizing radiation. It is applicable to humans or animals but not to microorganisms.Phagocytosis: The engulfing and degradation of microorganisms; other cells that are dead, dying, or pathogenic; and foreign particles by phagocytic cells (PHAGOCYTES).Antigens, Differentiation: Antigens expressed primarily on the membranes of living cells during sequential stages of maturation and differentiation. As immunologic markers they have high organ and tissue specificity and are useful as probes in studies of normal cell development as well as neoplastic transformation.Lymphokines: Soluble protein factors generated by activated lymphocytes that affect other cells, primarily those involved in cellular immunity.Biological Factors: Endogenously-synthesized compounds that influence biological processes not otherwise classified under ENZYMES; HORMONES or HORMONE ANTAGONISTS.Adjuvants, Immunologic: Substances that augment, stimulate, activate, potentiate, or modulate the immune response at either the cellular or humoral level. The classical agents (Freund's adjuvant, BCG, Corynebacterium parvum, et al.) contain bacterial antigens. Some are endogenous (e.g., histamine, interferon, transfer factor, tuftsin, interleukin-1). Their mode of action is either non-specific, resulting in increased immune responsiveness to a wide variety of antigens, or antigen-specific, i.e., affecting a restricted type of immune response to a narrow group of antigens. The therapeutic efficacy of many biological response modifiers is related to their antigen-specific immunoadjuvanticity.Mice, Inbred DBANeutrophil Activation: The process in which the neutrophil is stimulated by diverse substances, resulting in degranulation and/or generation of reactive oxygen products, and culminating in the destruction of invading pathogens. The stimulatory substances, including opsonized particles, immune complexes, and chemotactic factors, bind to specific cell-surface receptors on the neutrophil.Blood Cells: The cells found in the body fluid circulating throughout the CARDIOVASCULAR SYSTEM.Receptors, IgG: Specific molecular sites on the surface of various cells, including B-lymphocytes and macrophages, that combine with IMMUNOGLOBULIN Gs. Three subclasses exist: Fc gamma RI (the CD64 antigen, a low affinity receptor), Fc gamma RII (the CD32 antigen, a high affinity receptor), and Fc gamma RIII (the CD16 antigen, a low affinity receptor).Culture Media, Conditioned: Culture media containing biologically active components obtained from previously cultured cells or tissues that have released into the media substances affecting certain cell functions (e.g., growth, lysis).Ifosfamide: Positional isomer of CYCLOPHOSPHAMIDE which is active as an alkylating agent and an immunosuppressive agent.Macrophage-1 Antigen: An adhesion-promoting leukocyte surface membrane heterodimer. The alpha subunit consists of the CD11b ANTIGEN and the beta subunit the CD18 ANTIGEN. The antigen, which is an integrin, functions both as a receptor for complement 3 and in cell-cell and cell-substrate adhesive interactions.Amino Acid Sequence: The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.Blotting, Northern: Detection of RNA that has been electrophoretically separated and immobilized by blotting on nitrocellulose or other type of paper or nylon membrane followed by hybridization with labeled NUCLEIC ACID PROBES.Leukocytes: White blood cells. These include granular leukocytes (BASOPHILS; EOSINOPHILS; and NEUTROPHILS) as well as non-granular leukocytes (LYMPHOCYTES and MONOCYTES).Antigens, CD14: Glycolipid-anchored membrane glycoproteins expressed on cells of the myelomonocyte lineage including monocytes, macrophages, and some granulocytes. They function as receptors for the complex of lipopolysaccharide (LPS) and LPS-binding protein.Phosphorylation: The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.Erythroid Precursor Cells: The cells in the erythroid series derived from MYELOID PROGENITOR CELLS or from the bi-potential MEGAKARYOCYTE-ERYTHROID PROGENITOR CELLS which eventually give rise to mature RED BLOOD CELLS. The erythroid progenitor cells develop in two phases: erythroid burst-forming units (BFU-E) followed by erythroid colony-forming units (CFU-E); BFU-E differentiate into CFU-E on stimulation by ERYTHROPOIETIN, and then further differentiate into ERYTHROBLASTS when stimulated by other factors.Neoplasms: New abnormal growth of tissue. Malignant neoplasms show a greater degree of anaplasia and have the properties of invasion and metastasis, compared to benign neoplasms.Combined Modality Therapy: The treatment of a disease or condition by several different means simultaneously or sequentially. Chemoimmunotherapy, RADIOIMMUNOTHERAPY, chemoradiotherapy, cryochemotherapy, and SALVAGE THERAPY are seen most frequently, but their combinations with each other and surgery are also used.Vincristine: An antitumor alkaloid isolated from VINCA ROSEA. (Merck, 11th ed.)Fetal Blood: Blood of the fetus. Exchange of nutrients and waste between the fetal and maternal blood occurs via the PLACENTA. The cord blood is blood contained in the umbilical vessels (UMBILICAL CORD) at the time of delivery.Leukemia: A progressive, malignant disease of the blood-forming organs, characterized by distorted proliferation and development of leukocytes and their precursors in the blood and bone marrow. Leukemias were originally termed acute or chronic based on life expectancy but now are classified according to cellular maturity. Acute leukemias consist of predominately immature cells; chronic leukemias are composed of more mature cells. (From The Merck Manual, 2006)Tyrosine: A non-essential amino acid. In animals it is synthesized from PHENYLALANINE. It is also the precursor of EPINEPHRINE; THYROID HORMONES; and melanin.Mice, Knockout: Strains of mice in which certain GENES of their GENOMES have been disrupted, or "knocked-out". To produce knockouts, using RECOMBINANT DNA technology, the normal DNA sequence of the gene being studied is altered to prevent synthesis of a normal gene product. Cloned cells in which this DNA alteration is successful are then injected into mouse EMBRYOS to produce chimeric mice. The chimeric mice are then bred to yield a strain in which all the cells of the mouse contain the disrupted gene. Knockout mice are used as EXPERIMENTAL ANIMAL MODELS for diseases (DISEASE MODELS, ANIMAL) and to clarify the functions of the genes.DNA-Binding Proteins: Proteins which bind to DNA. The family includes proteins which bind to both double- and single-stranded DNA and also includes specific DNA binding proteins in serum which can be used as markers for malignant diseases.Membrane Glycoproteins: Glycoproteins found on the membrane or surface of cells.Heterocyclic Compounds: Ring compounds having atoms other than carbon in their nuclei. (Grant & Hackh's Chemical Dictionary, 5th ed)Fever: An abnormal elevation of body temperature, usually as a result of a pathologic process.Immunotherapy: Manipulation of the host's immune system in treatment of disease. It includes both active and passive immunization as well as immunosuppressive therapy to prevent graft rejection.Myeloid Cells: The classes of BONE MARROW-derived blood cells in the monocytic series (MONOCYTES and their precursors) and granulocytic series (GRANULOCYTES and their precursors).Enzyme-Linked Immunosorbent Assay: An immunoassay utilizing an antibody labeled with an enzyme marker such as horseradish peroxidase. While either the enzyme or the antibody is bound to an immunosorbent substrate, they both retain their biologic activity; the change in enzyme activity as a result of the enzyme-antibody-antigen reaction is proportional to the concentration of the antigen and can be measured spectrophotometrically or with the naked eye. Many variations of the method have been developed.Transcription, Genetic: The biosynthesis of RNA carried out on a template of DNA. The biosynthesis of DNA from an RNA template is called REVERSE TRANSCRIPTION.Monokines: Soluble mediators of the immune response that are neither antibodies nor complement. They are produced largely, but not exclusively, by monocytes and macrophages.Antibodies: Immunoglobulin molecules having a specific amino acid sequence by virtue of which they interact only with the ANTIGEN (or a very similar shape) that induced their synthesis in cells of the lymphoid series (especially PLASMA CELLS).Lymphocyte Activation: Morphologic alteration of small B LYMPHOCYTES or T LYMPHOCYTES in culture into large blast-like cells able to synthesize DNA and RNA and to divide mitotically. It is induced by INTERLEUKINS; MITOGENS such as PHYTOHEMAGGLUTININS, and by specific ANTIGENS. It may also occur in vivo as in GRAFT REJECTION.Respiratory Burst: A large increase in oxygen uptake by neutrophils and most types of tissue macrophages through activation of an NADPH-cytochrome b-dependent oxidase that reduces oxygen to a superoxide. Individuals with an inherited defect in which the oxidase that reduces oxygen to superoxide is decreased or absent (GRANULOMATOUS DISEASE, CHRONIC) often die as a result of recurrent bacterial infections.Growth Inhibitors: Endogenous or exogenous substances which inhibit the normal growth of human and animal cells or micro-organisms, as distinguished from those affecting plant growth (= PLANT GROWTH REGULATORS).Peritoneal Cavity: The space enclosed by the peritoneum. It is divided into two portions, the greater sac and the lesser sac or omental bursa, which lies behind the STOMACH. The two sacs are connected by the foramen of Winslow, or epiploic foramen.Drug Evaluation: Any process by which toxicity, metabolism, absorption, elimination, preferred route of administration, safe dosage range, etc., for a drug or group of drugs is determined through clinical assessment in humans or veterinary animals.STAT5 Transcription Factor: A signal transducer and activator of transcription that mediates cellular responses to a variety of CYTOKINES. Stat5 activation is associated with transcription of CELL CYCLE regulators such as CYCLIN KINASE INHIBITOR P21 and anti-apoptotic genes such as BCL-2 GENES. Stat5 is constitutively activated in many patients with acute MYELOID LEUKEMIA.Erythropoiesis: The production of red blood cells (ERYTHROCYTES). In humans, erythrocytes are produced by the YOLK SAC in the first trimester; by the liver in the second trimester; by the BONE MARROW in the third trimester and after birth. In normal individuals, the erythrocyte count in the peripheral blood remains relatively constant implying a balance between the rate of erythrocyte production and rate of destruction.Coculture Techniques: A technique of culturing mixed cell types in vitro to allow their synergistic or antagonistic interactions, such as on CELL DIFFERENTIATION or APOPTOSIS. Coculture can be of different types of cells, tissues, or organs from normal or disease states.Phosphotyrosine: An amino acid that occurs in endogenous proteins. Tyrosine phosphorylation and dephosphorylation plays a role in cellular signal transduction and possibly in cell growth control and carcinogenesis.Paclitaxel: A cyclodecane isolated from the bark of the Pacific yew tree, TAXUS BREVIFOLIA. It stabilizes MICROTUBULES in their polymerized form leading to cell death.Interleukin-11: A lymphohematopoietic cytokine that plays a role in regulating the proliferation of ERYTHROID PRECURSOR CELLS. It induces maturation of MEGAKARYOCYTES which results in increased production of BLOOD PLATELETS. Interleukin-11 was also initially described as an inhibitor of ADIPOGENESIS of cultured preadipocytes.Apoptosis: One of the mechanisms by which CELL DEATH occurs (compare with NECROSIS and AUTOPHAGOCYTOSIS). Apoptosis is the mechanism responsible for the physiological deletion of cells and appears to be intrinsically programmed. It is characterized by distinctive morphologic changes in the nucleus and cytoplasm, chromatin cleavage at regularly spaced sites, and the endonucleolytic cleavage of genomic DNA; (DNA FRAGMENTATION); at internucleosomal sites. This mode of cell death serves as a balance to mitosis in regulating the size of animal tissues and in mediating pathologic processes associated with tumor growth.Mice, Mutant Strains: Mice bearing mutant genes which are phenotypically expressed in the animals.Receptors, Cytokine: Cell surface proteins that bind cytokines and trigger intracellular changes influencing the behavior of cells.Trans-Activators: Diffusible gene products that act on homologous or heterologous molecules of viral or cellular DNA to regulate the expression of proteins.Antibody-Dependent Cell Cytotoxicity: The phenomenon of antibody-mediated target cell destruction by non-sensitized effector cells. The identity of the target cell varies, but it must possess surface IMMUNOGLOBULIN G whose Fc portion is intact. The effector cell is a "killer" cell possessing Fc receptors. It may be a lymphocyte lacking conventional B- or T-cell markers, or a monocyte, macrophage, or polynuclear leukocyte, depending on the identity of the target cell. The reaction is complement-independent.STAT3 Transcription Factor: A signal transducer and activator of transcription that mediates cellular responses to INTERLEUKIN-6 family members. STAT3 is constitutively activated in a variety of TUMORS and is a major downstream transducer for the CYTOKINE RECEPTOR GP130.DNA: A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).Up-Regulation: A positive regulatory effect on physiological processes at the molecular, cellular, or systemic level. At the molecular level, the major regulatory sites include membrane receptors, genes (GENE EXPRESSION REGULATION), mRNAs (RNA, MESSENGER), and proteins.Milk Proteins: The major protein constituents of milk are CASEINS and whey proteins such as LACTALBUMIN and LACTOGLOBULINS. IMMUNOGLOBULINS occur in high concentrations in COLOSTRUM and in relatively lower concentrations in milk. (Singleton and Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed, p554)Drug Therapy, Combination: Therapy with two or more separate preparations given for a combined effect.Peripheral Blood Stem Cell Transplantation: Transplantation of stem cells collected from the peripheral blood. It is a less invasive alternative to direct marrow harvesting of hematopoietic stem cells. Enrichment of stem cells in peripheral blood can be achieved by inducing mobilization of stem cells from the BONE MARROW.Cell Culture Techniques: Methods for maintaining or growing CELLS in vitro.Macrophages, Alveolar: Round, granular, mononuclear phagocytes found in the alveoli of the lungs. They ingest small inhaled particles resulting in degradation and presentation of the antigen to immunocompetent cells.Cell Adhesion: Adherence of cells to surfaces or to other cells.Remission Induction: Therapeutic act or process that initiates a response to a complete or partial remission level.Genetic Vectors: DNA molecules capable of autonomous replication within a host cell and into which other DNA sequences can be inserted and thus amplified. Many are derived from PLASMIDS; BACTERIOPHAGES; or VIRUSES. They are used for transporting foreign genes into recipient cells. Genetic vectors possess a functional replicator site and contain GENETIC MARKERS to facilitate their selective recognition.Infection: Invasion of the host organism by microorganisms that can cause pathological conditions or diseases.Mitoxantrone: An anthracenedione-derived antineoplastic agent.Breast Neoplasms: Tumors or cancer of the human BREAST.Polymerase Chain Reaction: In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.Cell Lineage: The developmental history of specific differentiated cell types as traced back to the original STEM CELLS in the embryo.Acute Disease: Disease having a short and relatively severe course.Mice, Inbred CBALymphocyte Culture Test, Mixed: Measure of histocompatibility at the HL-A locus. Peripheral blood lymphocytes from two individuals are mixed together in tissue culture for several days. Lymphocytes from incompatible individuals will stimulate each other to proliferate significantly (measured by tritiated thymidine uptake) whereas those from compatible individuals will not. In the one-way MLC test, the lymphocytes from one of the individuals are inactivated (usually by treatment with MITOMYCIN or radiation) thereby allowing only the untreated remaining population of cells to proliferate in response to foreign histocompatibility antigens.Proto-Oncogene Proteins c-kit: A protein-tyrosine kinase receptor that is specific for STEM CELL FACTOR. This interaction is crucial for the development of hematopoietic, gonadal, and pigment stem cells. Genetic mutations that disrupt the expression of PROTO-ONCOGENE PROTEINS C-KIT are associated with PIEBALDISM, while overexpression or constitutive activation of the c-kit protein-tyrosine kinase is associated with tumorigenesis.Stem Cells: Relatively undifferentiated cells that retain the ability to divide and proliferate throughout postnatal life to provide progenitor cells that can differentiate into specialized cells.Bronchoalveolar Lavage Fluid: Washing liquid obtained from irrigation of the lung, including the BRONCHI and the PULMONARY ALVEOLI. It is generally used to assess biochemical, inflammatory, or infection status of the lung.Epirubicin: An anthracycline which is the 4'-epi-isomer of doxorubicin. The compound exerts its antitumor effects by interference with the synthesis and function of DNA.Antigens, Differentiation, Myelomonocytic: Surface antigens expressed on myeloid cells of the granulocyte-monocyte-histiocyte series during differentiation. Analysis of their reactivity in normal and malignant myelomonocytic cells is useful in identifying and classifying human leukemias and lymphomas.Chemokines: Class of pro-inflammatory cytokines that have the ability to attract and activate leukocytes. They can be divided into at least three structural branches: C; (CHEMOKINES, C); CC; (CHEMOKINES, CC); and CXC; (CHEMOKINES, CXC); according to variations in a shared cysteine motif.Antineoplastic Agents: Substances that inhibit or prevent the proliferation of NEOPLASMS.RANK Ligand: A transmembrane protein belonging to the tumor necrosis factor superfamily that specifically binds RECEPTOR ACTIVATOR OF NUCLEAR FACTOR-KAPPA B and OSTEOPROTEGERIN. It plays an important role in regulating OSTEOCLAST differentiation and activation.