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D Metcalf

Publications and source records attributed to D Metcalf.

At least 235 records · Page 13Linked to original sources
PubMed1988

GM-CSF produced by recombinant vaccinia virus or in GM-CSF transgenic mice has no effect in vivo on murine cutaneous leishmaniasis.

The hemopoietic growth and differentiation regulators, granulocyte-macrophage colony-stimulating factor (GM-CSF) and the multipotential stimulating factor (multi-CSF) have been shown to have major effects on the effector function of mature macrophages. In this study we have examined the effect of recombinant GM-CSF and multi-CSF expressed transiently from recombinant vaccinia virus, or constitutively in GM-CSF transgenic mice on the development of cutaneous leishmaniasis, caused by Leishmania major in genetically susceptible or resistant mice. We observed no effect on the development of lesions when GM-CSF or multi-CSF were administered before infection, nor on the healing of lesions when they were administered after appearance of lesions. Although only some of the GM-CSF transgenic mice or their normal littermates developed lesions after infection with L. major, there was no difference between the groups in the rate of lesion development or in the size of lesions.

Animals↗
PubMed1988

Mechanisms contributing to the sex difference in levels of granulocyte-macrophage colony-stimulating factor in the urine of GM-CSF transgenic mice.

Levels of granulocyte-macrophage colony-stimulating factor (GM-CSF) were 30- to 40-fold higher in the urine of male GM-CSF transgenic mice than in female transgenic mice, despite uniform elevations in both sexes of serum GM-CSF levels. Male transgenic bladder tissue produced two to four times more GM-CSF in vitro than female transgenic or control bladder tissue, but no sex differences were observed in the production of GM-CSF in vitro by kidney tissue. No sex differences were observed in the serum half-lives of native or recombinant GM-CSF in C57BL or littermate control mice, and the half-lives of recombinant GM-CSF were shorter than those of native GM-CSF. The studies indicated that some GM-CSF in urine can represent plasma GM-CSF cleared by the kidney, and native GM-CSF was cleared to the urine more efficiently than recombinant GM-CSF. Female transgenic mice exhibited a subnormal capacity to clear injected native GM-CSF to the urine. Although granulomas were present in the bladder wall of some transgenic mice, their presence did not correlate with the GM-CSF levels in the urine.

Animals↗
PubMed1988

Biochemical characterization of murine leukaemia inhibitory factor produced by Krebs ascites and by yeast cells.

A cDNA library was constructed using mRNA from Krebs ascites tumor cells that was shown by Northern blot hybridization to contain mRNA for murine leukemia inhibitory factor (LIF). This library was screened with an oligonucleotide corresponding to the 3' end of a partial LIF cDNA clone, and an overlapping cDNA clone isolated. Nucleotide sequence analysis of this latter clone allowed the complete sequence of LIF to be derived. A cDNA molecule encoding the entire mature LIF protein was installed in a yeast expression vector, and LIF produced up to about 100 ng/ml in the growth medium. The LIF produced by yeast cells has the same biologic properties as native LIF and competes with native 125I-LIF for binding to specific cellular receptors. Two forms of native LIF, distinguishable by their chromatographic behavior on DEAE-Sepharose, were converted by neuraminidase treatment to a form with similar chromatographic behavior, suggesting that the major difference between these two species is the content of sialic acid on the carbohydrate portion. Moreover, yeast-derived recombinant LIF appears to display a different pattern of glycosylation to both forms of native LIF. From in vitro experiments, we conclude that the nature of the glycosylation is not crucial to biologic activity.

Animals↗
PubMed1988

The detection and initial characterization of colony-stimulating factors in synovial fluid.

In this study which included 16 patients with inflammatory or non-inflammatory arthropathies, human granulocyte-macrophage colony-stimulating activity was detected in synovial fluid. This was attributable to the presence of colony-stimulating factor(s) (CSF), as a direct action on human bone marrow progenitor cells was demonstrated using clone transfer experiments. Samples of synovial fluid also stimulated the growth of murine macrophage colonies and induced differentiation in the murine myelomonocytic leukemia cell line, WEHI-3B(D+), which are characteristic properties of human macrophage-CSF or granulocyte-CSF respectively. These findings and the results of preliminary fractionation procedures suggested that the colony-stimulating activity in synovial fluid was not explicable by the presence of any one of the well-characterized human CSF acting in isolation. This provides a new insight into the pathogenesis of inflammatory arthropathies and supports the hypothesis that CSF have important roles in vivo in addition to the regulation of haemopoiesis.

Adult↗
PubMed1988

Effects of recombinant human granulocyte colony-stimulating factor on hematopoietic progenitor cells in cancer patients.

Hematopoietic progenitor cell levels were monitored in the peripheral blood and bone marrow of 30 cancer patients receiving recombinant human granulocyte-colony stimulating-factor (rG-CSF) in a phase I/II clinical trial. The absolute number of circulating progenitor cells of granulocyte-macrophage, erythroid, and megakaryocyte lineages showed a dose-related increase up to 100-fold after four days of treatment with rG-CSF and often remained elevated two days after the cessation of therapy. The relative frequency of different types of progenitor cells in peripheral blood remained unchanged. The frequency of progenitor cells in the marrow was variable after rG-CSF treatment but in most patients was slightly decreased. The responsiveness of bone marrow progenitor cells to stimulation in vitro by rG-CSF and granulocyte-macrophage colony-stimulating factor did not change significantly during rG-CSF treatment. In patients nine days after treatment with melphalan and then rG-CSF, progenitor cell levels were very low with doses of rG-CSF at or below 10 micrograms/kg/d, but equaled or exceeded pretreatment values when 30 or 60 micrograms/kg/d of rG-CSF was given.

Bone Marrow↗
PubMed1988

A model system for leukemic transformation of immortalized hemopoietic cells in irradiated recipient mice.

Proliferation in vitro of the murine hemopoietic cell line FDC-P1 is dependent on stimulation by granulocyte-macrophage colony stimulating factor or multipotential colony stimulating factor. Although immortalized, the cells are not tumorigenic on subcutaneous inoculation. Intravenous injection of FDC-P1 cells into syngeneic DBA/2 mice was followed by the development of transplantable leukemias in 15% of nonirradiated animals and in virtually all animals that had received 100-350 rad whole-body irradiation prior to injection. Karyotypic analysis showed that the leukemias originated from FDC-P1 cells, and primary tumor cells from different animals displayed a wide spectrum of altered growth patterns when cultured in agar. In most cases, colony formation by leukemic cells in vitro exhibited autonomy with respect to stimulation by exogenous colony stimulating factors. These observations indicate that leukemic transformation of FDC-P1 cells is enhanced by irradiation of recipient mice and document a useful model for analyzing the mechanisms by which irradiation induces leukemia.

Animals↗
PubMed1987

Molecular cloning and expression of cDNA encoding a murine myeloid leukaemia inhibitory factor (LIF).

Leukaemia inhibitory factor (LIF) can induce macrophage differentiation in M1 murine myeloid leukaemic cells and suppress their proliferation in vitro. It does not stimulate the proliferation of normal progenitor cells and is apparently distinct from known colony-stimulating factors. We have used oligo-nucleotides complementary to partial amino acid sequence of LIF to isolate a LIF clone from a T lymphocyte cDNA library. When this cDNA was coupled to a yeast expression vector (YEpsec1) and introduced into yeast cells, a molecule with the biological properties characteristic of native LIF was secreted into the growth medium. The amino acid sequence of LIF established it to be a unique molecular entity, distinct from the other known haemopoietic growth factors. Since LIF is encoded by a unique gene, two biochemically separable forms of LIF probably represent post-transcriptional or posttranslational variants of the same gene product. In contrast to several other haemopoietic regulators, the 0.8- to 1-kb LIF mRNA was expressed constitutively in two murine T lymphocyte cell lines examined, and its abundance was not enhanced by stimulation with concanavalin A. Cloning, sequencing and expressing LIF has resolved several discrepancies in the literature concerning the identity of factors capable of inducing differentiation of murine myeloid leukaemic cells in vitro.

Amino Acid Sequence↗
PubMed1987

The in vitro behavior of hemopoietic cells transformed by polyoma middle T antigen parallels that of primary human myeloid leukemic cells.

A retrovirus encoding polyoma middle T antigen has been used to infect a murine hemopoietic cell line (FDC-P1) dependent on either granulocyte-macrophage colony-stimulating factor (GM-CSF) or multipotential colony-stimulating factor (Multi-CSF). A number of cell lines have been established on the basis of their initial ability to proliferate in the absence of added colony-stimulating factor (CSF). The transformed lines display one of three patterns of growth in vitro: those able to grow fully autonomously; those whose proliferation depends on cell density; and those displaying dependence on added CSF regardless cell density. This latter class of cells are reminiscent of the majority of primary myeloid leukemic cells. Unlike parental FDC-P1 cells, all three classes of transformed cells are leukemogenic in syngeneic mice; moreover, they produce variable amounts of GM-CSF which we believe underlies their neoplastic behavior.

Animals↗
PubMed1987

Mutagenesis of murine granulocyte/macrophage-colony-stimulating factor reveals critical residues near the N terminus.

A number of cDNAs encoding mutant forms of the murine haemopoietic growth factor, granulocyte/macrophage-colony-stimulating factor (GM-CSF), have been derived by in vitro mutagenesis and expressed in simian COS cells. Determination of the biological activity of the mutant factors revealed that residues within the regions 11-15, 24-37, 47-49 and 81-89 are required for generating a functional GM-CSF molecule. In particular, truncation of either of two strongly predicted alpha helices near the N terminus of the molecule severely depresses the activity of the factor.

Amino Acid Sequence↗
PubMed1987

Transgenic mice expressing a hemopoietic growth factor gene (GM-CSF) develop accumulations of macrophages, blindness, and a fatal syndrome of tissue damage.

Transgenic mice carrying the murine granulocyte-macrophage colony stimulating factor (GM-CSF) gene expressed from a retroviral promoter exhibit elevated levels of GM-CSF in the serum, urine, peritoneal cavity, and eye. The eyes of transgenic mice are opaque, contain accumulations of macrophages, and develop retinal damage. Similarly, lesions containing macrophages develop in striated muscle. The mice also display an accumulation of large, often multinucleate, activated macrophages in the peritoneal and pleural cavities. The transgene is transcribed in peritoneal cells, as well as in eyes and infiltrated striated muscle. A high proportion of transgenic mice die with muscle wasting when aged 2-4 months, possibly because of macrophage activation resulting from the high levels of GM-CSF.

Animals↗
PubMed1987

The Wellcome Foundation lecture, 1986. The molecular control of normal and leukaemic granulocytes and macrophages.

The development of semisolid culture methods supporting the clonal proliferation and maturation of granulocytes and macrophages led to the discovery of a group of specific glycoproteins, the colony-stimulating factors (CSFs), whose function it is to control the proliferation and functional activity of granulocytes, macrophages and associated blood cells. The four known CSFs in the mouse and man have been purified and complementary DNAs (cDNAs) for each have been cloned. The injection of bacterially synthesized recombinant CSF into mice has demonstrated that these CSFs can function in vivo to regulate granulocyte and macrophage formation. A major physiological role played by these CSFs is to control resistance to invading microorganisms through mechanisms capable of extremely rapid activation. Because the CSFs are the only known proliferative factors for these cells, the CSFs are involved in the initiation and the emergence of myeloid leukaemia but, conversely, at least one of the CSFs, G-CSF, is able to suppress myeloid leukaemic populations because of the ability of the CSFs to initiate differentiation commitment in responding granulocytic and macrophage populations. The CSFs are promising agents for clinical use in the treatment of infections in patients with depressed granulocyte-macrophage formation and possibly in the management of some types of myeloid leukaemia.

Animals↗
PubMed1987

Purified colony stimulating factors (G-CSF and GM-CSF) induce differentiation in human HL60 leukemic cells with suppression of clonogenicity.

Purified recombinant human granulocyte-macrophage colony-stimulating factor (rHGM-CSF) and purified native murine granulocyte-CSF (G-CSF) both induced differentiation in HL60 cells as evidenced by expression of granulocyte and macrophage membrane antigens, although this was not accompanied by morphological evidence of differentiation. Both types of CSF suppressed clonogenic HL60 cells with evidence of complete clonal extinction. The suppression of clonogenic HL60 cells was preceded in some experiments by CSF-stimulated proliferation of HL60 cells, and this was most evident in cultures containing low concentrations of fetal calf serum (FCS).

Antigens, Surface↗
PubMed1987

Hemopoietic growth factors and oncogenes in myeloid leukemia development.

Most primary myeloid leukemias are dependent for proliferative stimulation on the glycoprotein colony-stimulating factors. These agents are therefore mandatory co-factors in the development of myeloid leukemia. The CSFs also modify oncogene transcription, and in model leukemogenesis experiments GM-CSF has been shown to be a proto-oncogene. However, most evidence is against an autocrine hypothesis of myeloid leukemia based solely on CSF production by emerging leukemic cells. Because the CSFs also have differentiation commitment actions, they can induce differentiation in myeloid leukemic cells, and G-CSF in particular has an impressive capacity to suppress myeloid leukemic populations by this action. The antagonistic actions of the CSFs on myeloid leukemic cells make it difficult to predict whether they will prove to be useful agents in the management of myeloid leukemias.

Animals↗
PubMed1987

The role of the colony-stimulating factors in resistance to acute infections.

A set of specific glycoproteins, the colony-stimulating factors, has been identified as regulating granulocyte and macrophage production and function. These colony-stimulating factors have now been purified and mass produced by recombinant technology. These versatile regulators are capable of providing the body both with an ultrarapid and sustained system for responding to infections. The granulocytes, macrophages and eosinophils involved in these responses appear likely to be key cell populations ensuring adequate resistance to acute infections and the colony-stimulating factors may prove to be valuable agents in the clinic for increasing resistance to life-threatening infections particularly in immunologically compromised patients.

Animals↗
PubMed1987

Primary human myeloid leukemia cells: comparative responsiveness to proliferative stimulation by GM-CSF or G-CSF and membrane expression of CSF receptors.

In vitro clonal culture of leukemic cells from patients with acute myeloid leukemia (AML) showed that cells from all subtypes tested could be stimulated to proliferate clonally either by purified recombinant human granulocyte-macrophage colony stimulating factor (GM-CSF) or by human cross-reactive, purified murine granulocyte CSF (G-CSF). The responsiveness of AML populations to CSF stimulation was quantitatively variable but was within the heterogeneous range exhibited by normal granulocyte-monocyte progenitor cells. A general concordance was noted between the proliferative effects of GM-CSF and G-CSF on the individual leukemic populations. All AML populations tested specifically bound 125I-labeled murine G-CSF; the level of labeling varied widely and correlated with AML subtype. Labeling levels on individual labeled leukemic cells were within the heterogeneous range exhibited by normal cells, but significant numbers of blast cells in M2, M4, and M5 AMLs appeared to lack membrane receptors for G-CSF. The level of labeling with G-CSF did not correlate with the frequency of clonogenic cells able to be stimulated by G-CSF. The data emphasized that GM-CSF and G-CSF are equivalent proliferative stimuli for human myeloid leukemia cells. Further, despite the potential ability of G-CSF to suppress murine leukemic cells, many AML blast cells lack significant numbers of G-CSF receptors. These considerations warrant caution in future attempts to use G-CSF in the therapy of acute myeloid leukemia.

Bone Marrow↗
PubMed1987

Hemopoietic responses in mice injected with purified recombinant murine GM-CSF.

Normal adult BALB/c, C57BL, and C3H/HeJ mice were injected intraperitoneally three times daily for six days with 6-200 ng purified, bacterially synthesized, murine recombinant GM-CSF. Mice injected with 200 ng rGM-CSF developed a twofold increase in blood neutrophils. In the peritoneal cavity, a dose-related rise was observed in macrophages (up to 15-fold), neutrophils (10- to 100-fold) and eosinophils (10- to 100-fold). Peritoneal macrophages exhibited 15-fold increased mitotic activity (to 7.6/10(3) cells) and increased phagocytic activity for antibody-coated erythrocytes. Increased numbers of infiltrating neutrophils and monocytes were observed in the liver and lung. Dose-related rises were observed in spleen weight (up to 50%) and the spleen content of monocytes (twofold) and nonerythroid progenitor cells (up to fourfold). A dose-related fall occurred in total marrow cellularity (40%) and total nonerythroid progenitor cells (37%-66%), but levels of neutrophils and monocytes remained constant. The data indicate that the injection of rGM-CSF to normal mice increases overall numbers of granulocytes and macrophages and the phagocytic activity of macrophages and provides direct evidence for the conclusion that GM-CSF is likely to function in vivo as a regulator of these cell populations.

Animals↗
PubMed1987

Quantitative responsiveness of murine hemopoietic populations in vitro and in vivo to recombinant multi-CSF (IL-3).

Purified, bacterially synthesized, recombinant Multi-CSF (rMulti-CSF) exhibited in vitro proliferative effects identical to those of native Multi-CSF on a broad range of progenitor cells from normal murine bone marrow and on the continuous cell line FD-CP1. The injection into normal adult mice of 6-200 ng purified rMulti-CSF three times daily for six days induced dose-related rises in peritoneal macrophages, neutrophils, and eosinophils, and in the spleen weight and content of megakaryocytes, mast cells, and progenitor cells, some responses being detectable with the lowest dose injected. No Multi-CSF was detected in the serum, organ extracts, or organ-conditioned medium from normal or endotoxin-injected mice. While the data indicate that even small doses of injected rMulti-CSF can produce detectable hemopoietic changes in normal adult mice, the pattern of these changes and the failure to detect Multi-CSF in vivo raise doubts that Multi-CSF plays a significant role as a regulator of hemopoiesis in normal adult life.

Animals↗