The receptor for the human granulocyte-macrophage colony-stimulating factor (GM-CSF) (GM-R) is a heterodimeric complex consisting of two subunits, GM-R alpha and GM-R beta. Structural analyses have shown a number of highly conserved amino acid motifs present in both GM-R alpha and GM-R beta. These motifs include QYFLY, CXW, XW, and WSXWS motifs in the extracellular domain; a conserved cysteine in the transmembrane domain; and the entire cytoplasmic domain, including the LXVLX box in the carboxy terminal region of the cytoplasmic domain.
View Article and Find Full Text PDFA new strategy in the treatment of acute myelogenous leukemia is to attempt to increase the growth fraction of clonal leukemic cells prior to administration of chemotherapeutic agents by the administration of hematopoietic growth factors. We have studied the effect of GM-CSF on the cell cycle status and Ki67 nuclear antigen expression of AML blasts in vitro. The effect of growth factors and stromal cell co-culture on Ki67 expression in leukemic cell lines was also examined.
View Article and Find Full Text PDFThe isolation and characterization of primitive hematopoietic cells and their purification in sufficient numbers is important in clinical and research marrow transplantation settings. As systems for large-scale isolation and amplification of such cells are developed, they may assume importance in transplantation, treatment of marrow failure and for gene therapy applications. Such cells have been isolated by numerous techniques and in this work, small-scale isolation of CD34+ cells by two immunoadsorption purification methods is compared with isolation by flow cytometry.
View Article and Find Full Text PDFMultiple adhesion receptors are involved in the interaction of hematopoietic cells with the marrow microenvironment. This work characterizes the expression of various adhesive receptors on normal early hematopoietic precursors and reviews how they might be altered in leukemic states. Early hematopoietic CD34+ cells express CD18, CD11a, CD49d, CD49e, CD44, ICAM-1, and ICAM-3.
View Article and Find Full Text PDFTwo partial cDNAs encoding the human interleukin-3 receptor alpha subunit (IL-3R alpha) were cloned from KG-1 leukemic cells using the polymerase chain reaction. Sequence analysis of these cDNAs predicted two single-amino-acid (aa) changes as compared with the published TF-1 leukemic cell IL-3R alpha sequence [Kitamura et al., Cell 66 (1991) 1165-1174].
View Article and Find Full Text PDFPatients with chronic myelogenous leukemia (CML) can be cured with allogeneic bone marrow transplantation. Over the past decade, it has become clear that immunological mechanisms, in the form of graft-versus-leukemia, constitute an integral part of this therapy. Because of limitations imposed by a lack of suitable donors, age, and toxicity, only a minority of patients can be offered allogeneic bone marrow transplantation (BMT).
View Article and Find Full Text PDFTumor metastasis is the primary cause of death for cancer patients. The metastatic cascade requires successful tumor cell invasion into and through vascular and parenchymal barriers. We have shown that autocrine motility factor (AMF, autotaxin) and the insulin-like growth factors (IGFs) induce tumor-cell migration.
View Article and Find Full Text PDFNine patients with relapsed or refractory Hodgkin disease or non-Hodgkin lymphoma underwent peripheral stem cell autografting because of a history of marrow involvement with visible lymphoma. Peripheral stem cells were collected during a process of unstimulated leukapheresis. Recovery to a neutrophil count of 0.
View Article and Find Full Text PDFGranulocyte-macrophage colony-stimulating factor (GM-CSF) and granulocyte colony-stimulating factor (G-CSF) are two of the growing number of recognized cytokines involved in the regulation of hematopoiesis. The purification of these factors and the subsequent cloning of the cDNAs which encode these proteins have led to their widespread clinical use in the setting of therapy or disease-induced myelosuppression. Although originally purified on the basis of their colony-stimulating properties, GM-CSF and G-CSF may also play important roles in the regulation of effector cell function.
View Article and Find Full Text PDFImmunol Ser
September 1992
A hypothetical pathway of GM-CSF-induced signaling in human neutrophils is presented in Figure 4. The earliest postreceptor events leading to activation of cellular kinases and phosphorylation of c-raf on tyrosine and serine remain a mystery. It is conceivable that downstream events such as the production of LTB4 and PAF as well as other autocrine or paracrine activators of neutrophil-activation function may be involved in neutrophil activation and priming, or they may be downstream events irrelevant in the signaling cascade.
View Article and Find Full Text PDFA rapid (2.5 h) direct enzyme immunoassay (EIA) for Clostridium difficile toxin A was developed for clinical use. Specimen centrifugation and filtration were not required.
View Article and Find Full Text PDFVeno-occlusive disease (VOD) of the liver is a serious and often lethal sequela to bone marrow transplantation. Although a history of prior hepatitis moderately increases the risk of VOD, reliable screening methods for identifying high risk patients are not available. New approaches to managing patients who develop serious VOD are needed.
View Article and Find Full Text PDFThe aim of the present study is to evaluate the involvement of human neutrophil tyrosine kinase(s) in the signal transduction mechanism of granulocyte-macrophage colony-stimulating factor (GM-CSF). Stimulation of neutrophils with GM-CSF resulted in a time- and dose-dependent phosphorylation of several proteins having estimated molecular weights of approximately 40, 55, 74, 97, 118, and 155 Kd, detected by immunoblot using a monoclonal antibody directed against phosphotyrosine. GM-CSF-induced tyrosine phosphorylation was inhibited in a dose- and time-dependent manner by the tyrosine kinase inhibitor erbstatin.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
September 1991
Granulocyte-macrophage colony-stimulating factor (GM-CSF) plays an important role in hematopoiesis and host defense via interaction with specific cell-surface receptors in target tissues. We identified a truncated, soluble form of the low-affinity GM-CSF receptor (GMR) in chorio-carcinoma cells. Low-affinity GMR cDNAs encoding both the membrane-bound and soluble receptors were obtained by PCR using primers corresponding to the published sequence.
View Article and Find Full Text PDFThe human granulocyte-macrophage colony-stimulating factor (GM-CSF) receptor (GM-R) is expressed on both hematopoietic and non-hematopoietic tissues. Although the receptor has been identified by cross-linking studies as an 84,000-dalton protein, very little is known about its biochemistry. In this report, we describe a soluble binding assay for the human GM-R which allowed us to characterize the receptor complex from various sources, including plasma membranes of placenta, neutrophils, and human myeloid leukemia cell lines.
View Article and Find Full Text PDFHuman granulocyte colony-stimulating factor (G-CSF) is a regulatory glycoprotein that stimulates the production of neutrophilic granulocytes from committed hematopoietic progenitor cells both in vitro and in vivo. In this report, we show that biosynthetic (recombinant) human G-CSF enhances colony formation by normal human bone marrow and the human myeloid leukemic cell lines, HL-60 and KG-1, as well as nonhematopoietic small cell lung cancer lines, H128 and H69. G-CSF also modulates multiple differentiated functions of human neutrophils, including enhanced oxidative metabolism in response to f-Met-Leu-Phe (f-MLP), increased antibody-dependent cell-mediated cytotoxicity (ADCC), and augmented arachidonic acid release in response to ionophore and chemotactic agents.
View Article and Find Full Text PDFHaemopoietic growth factors both stimulate the growth and maturation of marrow precursor cells and enhance the functional activities of mature myelomonocytic effector cells. These biological effects are consistent with the expression of functional colony stimulating factor receptors on granulocytes and monocytes as well as on those immature marrow cells with proliferative potential. As the number of defined haemopoietic growth factors increases, both general perspectives of effector cell function and pathways of growth factor-induced signal transduction become more complex and less clearly understood.
View Article and Find Full Text PDFHuman granulocyte-macrophage colony-stimulating factor (GM-CSF) both stimulates hematopoietic precursor cells to grow as well as enhances the function of mature effector cells, such as neutrophils, eosinophils and macrophages. All of the biological actions of GM-CSF appear to be mediated via binding to a single class of high-affinity receptors present on all responsive cells. Affinity cross-linking experiments demonstrate that the same 98 kDa cross-linked species seen on other GM-CSF-responsive cells is also detected on a choriocarcinoma cell line, JAR.
View Article and Find Full Text PDFJ Clin Microbiol
October 1989
Antimicrobial elution disks containing amoxicillin-clavulanic acid (Augmentin), cefotetan, ciprofloxacin, or norfloxacin were tested in the Avantage automated susceptibility test system. Performance was compared against an agar diffusion procedure in a three-site collaborative study. Results of 1,500 comparison with amoxicillin-clavulanic acid showed a full accord (agreement of both systems) of 93.
View Article and Find Full Text PDFSeven commonly used antimicrobial susceptibility testing methods were used to test the susceptibility of 150 isolates of Pseudomonas aeruginosa against gentamicin, tobramycin, amikacin, carbenicillin, and piperacillin. Results were compared with respect to the susceptibility characteristics of the population of isolates as defined by each method. Conventional methods included agar disk diffusion and agar dilution, carried out in accordance with current recommendations of the National Committee for Clinical Laboratory Standards, as well as broth microdilution testing with cation-supplemented Mueller-Hinton broth (CSMHB).
View Article and Find Full Text PDFHuman granulocyte-macrophage colony-stimulating factor (GM-CSF) stimulates multiple differentiated functions of mature neutrophils. Increased expression of leukocyte adhesion molecules and chemotactic receptors on GM-CSF-treated neutrophils suggested that GM-CSF may stimulate neutrophil degranulation. were assessed by quantitating the release of an exclusive component of the specific granules, vitamin B12 binding protein.
View Article and Find Full Text PDFHuman granulocyte-macrophage colony-stimulating factor (GM-CSF) stimulates the colony growth of myeloid progenitors in semisolid media, and enhances the function of mature effector cells, including neutrophils, monocytes, and eosinophils. Small cell carcinoma lines (SCCL) have properties of amine precursor uptake and decarboxylation (APUD) cells and express high levels of the enzyme, L-aromatic amino acid decarboxylase. We looked for possible expression of GM-CSF receptors on nonhematopoietic cells and found specific high-affinity binding of human GM-CSF to SCCL and to the SV40-transformed African green monkey kidney cell line, COS.
View Article and Find Full Text PDFPre-incubation of human neutrophils with pertussis toxin significantly inhibited the neutrophil-directed biologic actions of granulocyte-macrophage colony-stimulating factor (GM-CSF) in three separate assays: the induction of c-fos mRNA, the enhancement of both platelet-activating factor-induced mobilization of intracellular calcium, and stimulation of leukotriene synthesis by the calcium ionophore A23187. Cholera toxin did not have an effect on the latter two assays. Pre-treatment of human neutrophils with pertussis toxin did not affect the binding of GM-CSF to its surface receptor.
View Article and Find Full Text PDFHuman granulocyte-macrophage colony-stimulating factor (GM-CSF) is an in vitro and in vivo stimulator of human bone marrow myelomonocytic precursor cells and mature granulocyte and macrophage effector cells. We have compared the effect of GM-CSF on the synthesis of 5-lipoxygenase products induced by the chemotactic peptide fMet-Leu-Phe and the calcium ionophore A23187 in human neutrophils. Although GM-CSF alone did not stimulate detectable synthesis of products of the 5-lipoxygenase pathway, pre-incubation of neutrophils with 200 pM GM-CSF for 1 hour at 23 degrees C enhanced synthesis of leukotriene B4, its all-trans isomers and omega-oxidation products, and 5-hydroxyeicosatetraenoic acid in response to both the calcium ionophore A23187 (1.
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