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PubMed1975

The influence of mouse sera on colony formation and on the production of colony stimulating factor in vitro.

Results of studies on the in vitro production and release of colony stimulating factor (CSF), by bone associated cells cultivated in the presence or absence of mouse sera, are presented. Tissues from three strains of mice were shown to be equally effective in the production of CSF in vitro. Priming of the tissue donors by endotoxin 4 hours previously, or by irradiation 1, 7 or 15 days previously, significantly increased the CSF production. The addition of serum from normal mice to the culture medium had no effect on CSF production by tissue from normal mice but regularly inhibited CSF production by bones from irradiated animals. The inhibition was not due to the toxic effect of the sera on the CSF producing cells and was more pronounced in the cultures of NMRI than in the C57BL tissues. Some inhibition was also observed in cultures of tissue from endotoxin-primed NMRI mice. Extraction of the sera with ether removed the inhibitory material. The sera which inhibited the CSF production in vitro also inhibited the growth of granulocytic and macrophage colonies in soft agar cultures but did not inhibit the growth and DNA synthesis of cultured L-cells.

Animals↗

PubMed1990

[The humoral nature of the colony-stimulating action of bone marrow cells on stromal colony formation in bone marrow cultures].

In 24 hours adherent marrow cell cultures (AMCC) were represented by single stretched fibroblasts. In non-feeder-supplemented AMCC most of the CFU-f remained single fibroblasts or passed through 1-3 cell doublings [correction of dudlings]. The colony stimulating activity of irradiated marrow cells was found to be diffuse across the Millipore filter, which seems to indicate that haemopoietic marrow cells produce a colony stimulating factor which is required for triggering the CFU-f from the Go-period of the cell cycle into cell proliferation.

Animals↗

PubMed1977

Effect of Corynebacterium parvum on colony-stimulating factor and granulocyte-macrophage colony formation.

Because Corynebacterium parvum has tumor-inhibitory properties and stimulates granulocyte-macrophage production, it may have clinical value in combination with chemotherapy. The leukopoietic effect of killed suspensions of C. parvum was studied in mice using the technique of in vitro clonal culture of hematopoietic cells. After C. parvum injection, there was a prompt, sustained elevation of serum colony-stimulating factor followed by an increase in granulocyte-macrophage precursor cells in the spleen and increases in blood mononuclear and granulocyte cells. Colony-stimulating factor production is suggested as a major mechanism of stimulation of granulocyte-macrophage proliferation by C. parvum. Since rapidly proliferating hematopoietic cells may have increased sensititity to cytotoxic agents, the details of hematopoietic stimulation by C. parvum may be critical in the sequential timing of combined C. parvum and chemotherapy treatment to obtain maximal tumor inhibition and minimal hematopoietic toxicity.

Animals↗

PubMed1986

Purified colony-stimulating factors enhance the survival of human neutrophils and eosinophils in vitro: a rapid and sensitive microassay for colony-stimulating factors.

The survival of purified human blood neutrophils and eosinophils was monitored using microwell cultures. Survival was enhanced in cultures containing human or murine colony-stimulating factors (CSFs). The survival of both cell types was enhanced by purified recombinant human granulocyte-macrophage CSF and partially purified preparations of the native molecule, CSF alpha. Neutrophil but not eosinophil survival was enhanced by murine granulocyte-CSF and its human analogue CSF beta. Eosinophil but not neutrophil survival was enhanced by murine eosinophil differentiation factor (eosinophil CSF). The mature cell survival provided an assay system for CSF that was 10(2) to 10(3) more sensitive than the standard assay of stimulation of colony formation in agar cultures and could be completed within 48 hours. These results demonstrated that CSF induced and enhanced survival of mature human neutrophils and eosinophils in vitro. Furthermore, the lineage specificity of purified murine CSFs was retained in their action on human cells.

Animals↗

PubMed1979

Influence of classic immunosuppressants on spleen colony formation in mice. 3. Concentration of colony forming units in bone marrow and spleens of cyclophosphamide-treated mice.

The concentration of colony forming units (CFU) increased nonsignificantly in bone marrow, and significantly in spleens of cyclophosphamide-treated mice, but there was no increase in the absolute number of CFU in these organs due to decreased celullarity. The serum of mice pretreated with cyclophosphamide seems to have colony-stimulating activity.

Animals↗

PubMed1983

CCNU toxicity after an overdose in a patient with Hodgkin's disease. Effects on colony-forming cells (CFU-C) and colony-stimulating activity (CSA).

An overdose of CCNU (600 mg over a 15-d period) was unintentionally ingested by a patient with advanced Hodgkin's disease subjected to combination chemotherapy. A severe bone marrow depression occurred 3 weeks after the start of the CCNU treatment. The nadir of the platelet count was reached after 4 weeks and that of the granulocyte count after 5 weeks. At the nadir of the white blood cell count, colony-forming cells (CFU-C) were found in significantly reduced numbers in the bone marrow, and were not found at all in the peripheral blood; the amount of colony-stimulating activity (CSA) produced by peripheral blood cells was reduced. However, the cells producing CSA recovered earlier than the CFU-C, and the CSA peak value was reached about 1 week before the peak value for CFU-C in the bone marrow. Thus, in vivo CSA-producing cells appeared to be more resistant to CCNU than were CFU-C, and their recovery appeared to be a prerequisite for the recovery of CFU-C and myelopoietic cells.

Animals↗

PubMed1980

Studies on in vitro colony formation by mouse bone marrow cells using different inflammatory pleural exudates. Relation to colony stimulating factor (CSF).

An inflammatory exudate obtained in Swiss mice 3 hours after intrapleural injection of dextran was able to increase the number of cultivated peritoneal macrophages in S phase. This exudate was also able to stimulate the formation of colonies from mice bone marrow progenitors of macrophages and granulocytes in methylcellulose culture. The stimulating activity of this acute inflammatory exudate was compared with that of colony stimulating factor (GM.CSF). The qualitative and quantitative results showed that the biological activity of the mitogenic factor of this inflammatory exudate, inflammatory mitogenic factor (IMF) was very close to GM.CSF at optimal concentration, but when used at the same concentration, the exudate was less active than GM.CSF. A stimulating activity was also found with another inflammatory pleural exudate induced by calcium pyrophosphate. The comparative kinetics of the action of the two exudates on CFUc appeared alike but the rise was earlier with calcium pyrophosphate. These results suggest the release of a growth factor for monocyte-macrophage in different acute inflammatory exudates.

Animals↗

PubMed1981

Human placental conditioned medium (from different phase of pregnancy) as a source of colony-stimulating activity for cultures of human and mouse. granulocyte-macrophage colony-forming cells in semisolid agar.

We have investigated the effect of conditioned medium derived from cultures of human placental tissue from different phases of pregnancy on in vitro growth of human and mouse granulocyte-macrophage colony forming cells in semisolid agar. We have confirmed that the colony-stimulating activity of human placental conditioned (normal delivery) medium was equivalent to the activity of peripheral blood leucocyte underlayers when medium was added at a 5%-20% concentration to the semisolid agar. Placentas from the 12th amd 10th week of gestation were found not convenient for preparation of medium with high CSA; the activity of media prepared from their cultures was not significantly higher than the autostimulating activity of bone marrow alone. Human placental conditioned medium proved inconvenient for cultures of mouse GM-CFC in semisolid agar containing foetal calf serum.

Agar↗

PubMed1982

Colony-forming cell proliferation: a rapid and sensitive assay system for murine granulocyte and macrophage colony-stimulating factors.

A microculture assay for murine granulocyte-macrophage colony-stimulating factor (GM-CSF) has been developed using fetal liver GM colony-forming cells (CFC) isolated by fluorescence-activated cell sorting. These GM-CFC are free of mature hemopoietic cells, such as granulocytes and macrophages, which may interfere with direct assays for GM-CSF. The assay procedure allows the quantitation of GM-CSF within 48 hr by measuring the number of cells produced from 50 GM-CFC in microcultures (15 microliter). The assay is particularly simple to set up and score and yet, because of the reduced volumes, this assay is still capable of detecting 0.2 pg (i.e., 0.2 U) of GM-CSF within 48 hr, i.e., 100 times less GM-CSF than the conventional soft agar assay. By allowing the microcultures to develop for 7 days, the extra proliferation allows a further tenfold increase in the sensitivity of CSF detection. The time and cost of setting up hundreds of GM-CSF assays for fractions from chromatographic columns, e.g., reverse phase high performance liquid chromatography, is reduced by at least five-fold. Enough GM-CFC can be isolated and stored frozen in one afternoon to provide sufficient cells for the daily assay of 200 samples of GM-CSF for several months. Microassay results for several sources of GM-CSF at different stages of purification are compared to the results obtained from the soft agar assay.

Animals↗

PubMed1993

Effect of recombinant human granulocyte colony-stimulating factor treatment of mice on spleen colony-forming unit number and self-renewal capacity.

The aim of this investigation was to find out whether the self-renewal capacity of spleen colony-forming units (CFU-S) changed after treatment of CBF1 (CBA-LacxC57B1/6) F1 female mice with granulocyte colony-stimulating factor (G-CSF). In addition, the possibility of synergism between erythropoietin (Epo) and G-CSF in blood stem cell mobilization was studied. Twenty-five and 250 micrograms/kg/d injections of recombinant human (rh) G-CSF expanded the number of CFU-S in peripheral blood four- and 32-fold. The self-maintenance potential of CFU-S did not change significantly. The treatment of mice with 250 micrograms/kg/d rhG-CSF resulted in a two-fold increase of spleen cellularity and a 15-fold augmentation of CFU-S number, without noticeable changes in their self-renewal capacity. Moderate changes in CFU-S number were observed after Epo administration in spleen and peripheral blood; however, no significant synergistic effect of Epo was detected with either dose of rhG-CSF. The multifold increase of CFU-S number in peripheral blood following rhG-CSF administration, with no reduction in their generating potential, suggests that rhG-CSF-mobilized blood stem cells provide an appropriate source for reconstitution of the hematopoietic system.

Animals↗

PubMed1988

Granulocyte/macrophage colony-stimulating factor stimulates monocyte and tissue macrophage proliferation and enhances their responsiveness to macrophage colony-stimulating factor.

Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a specific humoral growth factor that stimulates both neutrophilic granulocyte and macrophage production by bone marrow hematopoietic progenitor cells. GM-CSF also stimulates the proliferation and clonal growth of both tissue macrophages and blood monocytes. Although at low concentrations GM-CSF was unable to support the long-term growth of tissue macrophages, it greatly enhanced their responsiveness to macrophage CSF (M-CSF, or CSF-1). This effect was also observed by treating macrophages with GM-CSF for a short time. GM-CSF did not compete with M-CSF for binding to M-CSF receptors nor was it inactivated by treatment with anti-M-CSF antiserum. Treatment of tissue macrophages with GM-CSF led to a rapid but transient downregulation of M-CSF receptors; prolonged incubation at 37 degrees C, however, resulted in a restoration and upregulation of M-CSF receptors. Identical effects were observed with both native or recombinant GM-CSF. This study suggests that GM-CSF regulates tissue macrophage production by two modes of action: (a) direct stimulation of macrophage proliferation, and (b) enhancement of their responsiveness to M-CSF.

Animals↗

PubMed1994

Cytotoxicity of white blood cells activated by granulocyte-colony-stimulating factor, granulocyte/macrophage-colony-stimulating factor and macrophage-colony-stimulating factor against tumor cells in the presence of various monoclonal antibodies.

Unconjugated monoclonal antibodies (mAb) kill tumor cells in vivo by activating immune functions. One of these is ADCC (antibody-dependent cellular cytotoxicity). The efficacy of mAbs might be augmented if the cytotoxic capacity of the effector cells could be increased. In this study the augmenting effect of granulocyte-colony-stimulating factor (G-CSF), granulocyte/macrophage(GM)-CSF and macrophage(M)-CSF was analyzed. Effector cells [peripheral blood mononuclear cells (PBMC) or granulocytes] were activated for 4-6 h by the respective CSF and assayed in an 18-h Cr51-release assay. Human colorectal, lymphoma, glioma and melanoma cell lines were target cells. Mouse mAbs of different isotypes, as well as chimeric and humanized mAbs, were used. mAbs having the human Fc part of the IgG molecule were the most effective. The killing capacity of PBMC as well as of granulocytes was statistically significantly enhanced when mAbs were added. M-CSF and GM-CSF were the best CSF for augmenting the lytic capacity of PBMC in ADCC. G-CSF had no significant effect on PBMC. Spontaneous cytolysis of PBMC was significantly augmented only by M-CSF. Granulocytes were, in general, significantly less effective than PBMC but may be equally effective killer cells together with mouse or human mAbs of the IgG1 isotype, particularly against melanoma cells. Granulocytes may also be significantly stimulated to increased lytic capacity when activated with G-CSF or GM-CSF. On the basis of the present evaluation, clinical trials in tumor patients are warranted, combining mAbs with GM-CSF or M-CSF. Preference might be given to GM-CSF as this cytokine activates both PBMC and granulocytes.

Adult↗

PubMed1998

Mature and immature myeloid cells decrease the granulocyte colony-stimulating factor level by absorption of granulocyte colony-stimulating factor.

We studied the effects of polymorphonuclear neutrophils (PMN) and immature myeloid cells on the granulocyte colony-stimulating factor (G-CSF) level in vitro to better understand the regulatory mechanisms of neutropoiesis. Intact normal PMN decreased the G-CSF level after incubation with recombinant human (rh) G-CSF in a time- and dose-dependent manner. The percent reduction decreased as the concentration of rhG-CSF increased. However, the cell-free PMN-conditioned medium (PMN-CM) did not decrease the G-CSF level. The intact PMN also decreased the granulocyte-macrophage (GM)-CSF level after culture with rhGM-CSF, but did not affect the monocyte (M)-CSF level after culture with rhM-CSF. Normal bone marrow (BM) immature neutrophilic cells and G-CSF-dependent acute myeloid leukemic cells (OCI/AML la) also decreased the G-CSF level, whereas K-562 cells, which have no detectable G-CSF receptors, did not affect it. Phenylarsine oxide (PhAsO), an inhibitor of endocytosis of ligand receptor complex, abrogated this decreasing effect of intact PMN and OCI/AML la cells. These findings suggest that mature and immature myeloid cells negatively regulate neutropoiesis by, at least in part, decreasing the G-CSF level probably through receptor-mediated continual absorption and metabolism of G-CSF.

Absorption↗

PubMed1990

Differential effects of granulocyte-macrophage colony-stimulating factor and granulocyte colony-stimulating factor in children with severe congenital neutropenia.

Severe congenital neutropenia (SCN) is a disorder of myelopoiesis characterized by severe neutropenia secondary to a maturational arrest at the level of promyelocytes. We treated five patients with SCN with recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) for 42 days and subsequently, between 1 and 3 months later, with rhG-CSF for 142 days. The objective was to evaluate the safety and ability of these factors to elicit a neutrophil response. rhGM-CSF was administered at a dose of 3 to 30 micrograms/kg/d (30 to 60 minutes, intravenously). In all patients, a specific, dose-dependent increase in the absolute granulocyte counts was observed. However, in four patients this increase was due to an increase in eosinophils, and in only one patient it was due to an increase in the absolute neutrophil counts (ANC). Subsequently, all patients received rhG-CSF at a dose of 3 to 15 micrograms/kg/d subcutaneously. In contrast to rhGM-CSF treatment, all five patients responded to rhG-CSF during the first 6 weeks of treatment with an increase in the ANC to above 1,000/microL. The level of ANC could be maintained during maintenance treatment. In one patient, the increase in ANC was associated with an improvement of a severe pneumonitis caused by Peptostreptococcus and resistant to antibiotic treatment. No severe bacterial infections occurred in any of the patients during CSF treatment. All patients tolerated rhGM-CSF and rhG-CSF treatment without severe side effects. These results demonstrate the beneficial effect of rhG-CSF in SCN patients.

Agranulocytosis↗

PubMed1990

Granulocyte-macrophage colony-stimulating factor suppresses induction of neutrophil alkaline phosphatase synthesis by granulocyte colony-stimulating factor.

We evaluated the in vitro effects of recombinant human (rh) granulocyte colony-stimulating factor (G-CSF) and rh granulocyte-macrophage CSF (GM-CSF) on neutrophil alkaline phosphatase (NAP) activity and the incorporation of amino acids into polymorphonuclear leukocytes (PMN) from normal individuals and patients with chronic myelogenous leukemia (CML). Both the NAP activity and incorporation of amino acids into PMN were enhanced by the addition of G-CSF in a dose-dependent manner. NAP activity induced by G-CSF in PMN from CML patients showed a greater increase than that in PMN from normal controls. In contrast to G-CSF, GM-CSF did not affect the NAP activity in PMN in spite of the enhanced incorporation of amino acids into PMN by GM-CSF. Interestingly, both the NAP-inducing ability of G-CSF and its enhancing ability for amino acid incorporation were suppressed by GM-CSF in a dose-dependent manner when PMN were incubated with various concentrations of GM-CSF in addition to 100 ng/ml of G-CSF. These observations suggest that G-CSF and GM-CSF act differently: G-CSF induces NAP synthesis in PMN, whereas GM-CSF negatively modulates the effect of G-CSF. Further, it is suggested that protein synthesis induced by G-CSF is negatively modulated by GM-CSF in a general fashion.

Alkaline Phosphatase↗

PubMed1990

Proliferation, macrophage colony-stimulating factor, and macrophage colony-stimulating factor-receptor expression of alveolar macrophages in active sarcoidosis.

Alveolar macrophages (AM) in sarcoidosis display an enhanced mitotic activity. Immunocytochemical detection of the proliferation-associated Ki-67 antigen revealed significant increase in the number of proliferating AM in active sarcoidosis as compared with inactive stages of disease. Macrophage proliferation may provide an additional marker of disease activity. Since growth of macrophages is regulated by hematopoietic growth factors, we examined the expression of macrophage colony-stimulating factor (M-CSF), granulocyte M-CSF, and interleukin-3 by bronchoalveolar lavage cells in active sarcoidosis. Expression of granulocyte M-CSF or interleukin-3 genes could not be detected. AM in active sarcoidosis displayed M-CSF RNA to a comparable level like normal AM. They differed, however, in about 50% of cases analyzed, from normal AM by an enhanced level of c-fms proto-oncogene (M-CSF-receptor) expression. The enlarged proportion of proliferating AM in active sarcoidosis may be the result of an increased influx of strongly fms expressing macrophage precursors into the alveoli and autostimulation of macrophages by M-CSF.

Adult↗

PubMed1990

Comparison of the effects of IL-3, granulocyte-macrophage colony-stimulating factor, and macrophage colony-stimulating factor in supporting monocyte differentiation in culture. Analysis of macrophage antibody-dependent cellular cytotoxicity.

Cultured human monocytes undergo a process of differentiation and maturation lasting 5 to 10 days that ultimately leads to the appearance of large macrophage-like cells. This differentiation is growth factor dependent: of all the cytokines tested, only macrophage colony-stimulating factor (M-CSF), granulocyte/macrophage-CSF (GM-CSF), and IL-3 proved capable of supporting the differentiation and the long term survival of the macrophage-like cells. Although all three cytokines yield cells with macrophage characteristics, cells developed in M-CSF have features distinct from those matured in either IL-3 or GM-CSF. At the morphologic level, the M-CSF-supported monocyte cultures yield elongated, spindle-shaped cells whereas those supported with IL-3 or GM-CSF yielded round cells with distinct nuclei. All three macrophage populations expressed similar levels of HLA-DR, CD11b, and CD11c, but the M-CSF-treated cultures yielded more CD14+ and CD16+ (Fc gamma RIII) cells. All three cell populations developed capacity for antibody-dependent cellular cytotoxicity (ADCC) as well as antibody-independent cytotoxicity with peak activity achieved after 8 to 12 days in culture. ADCC capacity developed earliest and the level of activity was usually greatest in the M-CSF-treated cultures, possibly correlating with the higher level of expression of CD16. Our findings indicate that any of these cytokines, but particularly M-CSF, may be useful clinically in enhancing the tumoricidal capacity of tumor-specific mAb through augmentation of macrophage capacity for ADCC.

Antibody-Dependent Cell Cytotoxicity↗

PubMed1988

Tumor necrosis factor-alpha and tumor necrosis factor-beta (lymphotoxin) stimulate the production of granulocyte-macrophage colony-stimulating factor, macrophage colony-stimulating factor, and IL-1 in vivo.

A number of cell types have been shown to elaborate hematopoietic growth factors in response to inflammatory mediators in vitro. To determine if this response occurs in vivo, we have administered levels of TNF-alpha and TNF-beta (lymphotoxin) found during an inflammatory reaction to mice. Using Northern blot analysis to detect tissue levels of hematopoietic growth factor-specific transcripts, and specific biologic and immunologic assays to detect the presence of colony-stimulating factors in the serum, we have found that TNF-alpha and TNF-beta induce the transcription and production of granulocyte-macrophage-CSF, macrophage-CSF, and IL-1. These findings provide an in vivo mechanism for the hematopoietic response to inflammation.

Animals↗