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PubMed1989

Interleukin-3 is significantly more effective than other colony-stimulating factors in long-term maintenance of human bone marrow-derived colony-forming cells in vitro.

Human bone marrow cells cultured for 21 days in the presence of recombinant human interleukin-3 (IL-3) produced up to 28 times more colony-forming cells (CFC) than could be obtained from cultures stimulated with granulocyte colony stimulating factor (G-CSF) or granulocyte-macrophage CSF (GM-CSF). IL-3-cultured cells retained a multipotent response to IL-3 in colony assays but were restricted to formation of granulocyte colonies in G-CSF and granulocyte or macrophage colonies in GM-CSF. Culture of bone marrow cells in IL-3 also led to accumulation of large numbers of eosinophils and basophils. These data contrast with the effects of G-CSF, GM-CSF, and IL-3 in seven-day cultures. Here both GM-CSF and IL-3 amplified total CFC that had similar multipotential colony-forming capability in either factor. G-CSF, on the other hand, depleted IL-3-responsive colony-forming cells dramatically, apparently by causing these cells to mature into granulocytes. The data suggest that a large proportion of IL-3-responsive cells in human bone marrow express receptors for G-CSF and can respond to this factor, the majority becoming neutrophils. Furthermore, the CFC maintained for 21 days in IL-3 may be a functionally distinct population from that produced after seven days culture of bone marrow cells in either IL-3 or GM-CSF.

Bone Marrow↗
PubMed1988

Effects of granulocyte-macrophage colony-stimulating factor and colony-stimulating factor-1 on the proliferation and differentiation of murine alveolar macrophages.

Murine alveolar macrophages (AM) were shown to have proliferative ability and to form colonies in vitro. The factors in lung-conditioned medium (CM) and L929-CM which stimulate the proliferation of AM were considered to be granulocyte-macrophage colony-stimulating factor (GM-CSF) and CSF-1, respectively, because recombinant murine (rm)GM-CSF and recombinant human (rh)CSF-1 could replace the activities of lung-CM and L929-CM, respectively. The phenotype of the cells in the colonies formed by AM incubated with rmGM-CSF or lung-CM was AM-like; more than 90% of the cells were stained by anti-asialo GM1 but not by FITC-LPS, and had AM-like morphology. Expression of Mac-1 Ag determined by M1/70HL in these cells as well as original AM was low. However, the phenotype of the cells in the colonies formed by AM incubated with rhCSF-1 or L929-CM was peritoneal macrophage (PM)-like; more than 90% of the cells were stained by FITC-LPS and M1/70HL, but not by anti-asialo GM1, and showed PM-like morphology. The cells in the colonies formed by AM incubated with rmGMCSF changed their phenotype after treatment with rhCSF-1; the percentage of cells stained by anti-asialo GM1 decreased, and that of cells stained by FITC-LPS increased. The cells in the colonies formed by AM incubated with rhCSF-1 never changed their phenotype after incubation with rmGM-CSF. In contrast to AM, more than 90% of the cells in all colonies formed by PM incubated with either rmGM-CSF, rhCSF-1, lung-CM, or L929-CM were stained by FITC-LPS but not by anti-asialo GM1. These results show that although AM and PM can proliferate, AM, in contrast to PM, are bipotential cells that can differentiate into two types of macrophages responding to distinct types of CSF, and that one of the molecular mechanisms controlling macrophage heterogeneity may be based on the type of CSF produced at distinct tissues.

Animals↗
PubMed1985

Human B-lymphocyte colony responses: suboptimal colony responsiveness in aged humans associated with defective function of B cells and monocytes.

The abilities of human B cells from young and aged subjects to form colonies in semisolid cultures stimulated with Staphylococcus protein A were investigated. Approximately three-fourths of aged adults had significantly diminished colony responses compared to young adults. In 55% of these aged adults, the in vitro blocking of monocyte prostaglandin synthesis lead to a 1.5-fold or greater augmentation of the depressed colony responses. Other experiments showed that the improvement with indomethacin could not be explained by the greater sensitivity of aged versus young B-cell colony precursors to prostaglandin suppression. However, indomethacin failed to improve the depressed colony responses of the remaining aged adults. This failure could not be attributed to deficient interleukin 1 production, detectable alterations in accessory cell subsets of monocytes, or the lack of potential colony precursors bearing sIgD/M. Instead, the B cells from these aged subjects demonstrated a substantial decrease in the capping of sIgD/M compared to the B cells of aged subjects which displayed improved colony responses with indomethacin and compared to the B cells from young adults. Thus, these data indicate that the diminished B-cell colony responses of aged humans represent aberrancies within both the B-cell and monocyte lineages which might coexist.

Adult↗
PubMed1990

Enhanced stimulation of human bone marrow macrophage colony formation in vitro by recombinant human macrophage colony-stimulating factor in agarose medium and at low oxygen tension.

Recombinant (r) and natural human (h) macrophage colony-stimulating factor (M-CSF, CSF-1) have been considered poor stimulators of macrophage progenitor cells present in human marrow, although they are potent stimulators of these cells in mouse marrow. We compared the growth characteristics of rhM-CSF-responsive human macrophage progenitor cells placed in semisolid agarose or agar culture medium and incubated for 14 days at ambient (approximately 20%) or lowered (5%) O2 tension. By itself, rhM-CSF was found to be a good stimulator of macrophage colony formation by human bone marrow cells cultured in agarose but not in agar; this growth was enhanced by incubation at 5% O2. Maximal numbers (up to 115/10(5) nonadherent low density cells plated) of macrophage colonies (50 to greater than 500 cells per colony) were stimulated by 500 to 1,000 units rhM-CSF/mL, with 1/2 maximal numbers stimulated by 250 to 500 units/mL. With agarose as the support medium, rhM-CSF was two- to fourfold more active on mouse than on human macrophage colony formation, in contrast to previous reports of 10- to 100-fold greater activity when agar was used as the support medium. Using nonadherent low density T lymphocyte-depleted human bone marrow cells growing in agarose at 5% O2, greater than additive effects on colony formation were observed when 31 to 500 units rhM-CSF were used in combination with either 10 ng rh interleukin-1 alpha (IL-1 alpha), 20, or 200 units rh granulocyte-macrophage (GM)-CSF or rhG-CSF. The agarose assay system should be useful for evaluating factors regulating the proliferation of human macrophage progenitor cells in vitro and during clinical trials with rhM-CSF.

Agar↗
PubMed1989

Colony-stimulating factors in B-cell colony formation in patients with B-cell chronic lymphocytic leukemia.

A new in vitro colony growth assay system method was found to be reliable in its use for evaluating B-cell proliferation in normal subjects and in 9 patients with B-cell chronic lymphocytic leukemia (B-CLL). The method is based on a phytohemagglutinin (PHA)-stimulated monocyte and T-cell-conditioned medium (PHA-MTCM) composed of PHA, silica, normal monocytes and normal T cells. The number of colonies proliferated was significantly greater in 5 patients who had not undergone treatment than in normal subjects (1,417 +/- 660 vs. 661 +/- 119) (p less than 0.002). Normal cultured B-cell colonies were shown to be 71% surface IgM colonies, and 6% cytoplasmic IgA colonies with the appearance of blastic cells. B-CLL colonies, on the other hand, were demonstrated to be monoclonal with the same CLL circulating cells being retained. We also studied the effect of interleukin-2 (IL-2) on B-cell colony growth assay in 4 patients with B-CLL cells. Only 1 patient with M protein responded to IL-2, proliferated and expressed IL-2 receptors. Although 3 patients without M protein did not respond to IL-2, they did respond to the supernatant, and they proliferated but expressed no IL-2 receptors.

Adult↗
PubMed1991

Interactions among granulocyte-macrophage colony-stimulating factor, macrophage colony-stimulating factor, and IFN-gamma lead to enhanced proliferation of murine macrophage progenitor cells.

This report examines the actions of IFN-gamma on monocytopoiesis in murine liquid and semisolid bone marrow cultures. The proliferative response of bone marrow cells to macrophage CSF and granulocyte-macrophage CSF was assayed by measuring [3H]TdR uptake in a range of mouse strains. No interstrain difference in kinetics was observed for CSF-1 action, but GM-CSF acted significantly more rapidly on C57B1/6, Swiss, and to a lesser extent A/J mice than on BALB/c or CBA. IFN-gamma inhibited [3H]TdR incorporation elicited by CSF-1, and to a much lesser extent, GM-CSF. When the two CSF were added together, the effects were not additive; in fact, the response was the same as that seen with GM-CSF alone. When IFN-gamma was also added, the response was restored to the level seen with CSF-1 alone. In essence, the inhibitory actions of GM-CSF and IFN-gamma were mutually exclusive. The mechanism of these actions was investigated using colony assays. As expected, CSF-1 caused the formation of pure macrophage colonies, whereas GM-CSF stimulated production of macrophage, granulocyte, and mixed granulocyte macrophage colonies. When the two CSF were added in combination, the total colony count was greater than with either alone, but less than additive. The number of pure macrophage colonies was reduced to the number seen with GM-CSF alone. IFN-gamma reduced the number of colonies in the presence of CSF-1, but slightly increased the number with GM-CSF. In the presence of both CSF, IFN-gamma increased the colony count by around 25 to 40%, so that the numbers were greater than the combined total of CSF-1 plus GM-CSF added separately. Similar results were obtained in all mouse strains tested. The results suggest that the thymidine uptake data reflect changes in the number of progenitor cells responding rather than changes in cell cycle time. The results are discussed in terms of the possibility that coadministration of GM-CSF and CSF-1 could ameliorate the myelosuppressive actions of IFN-gamma in vivo, leading to more effective use of this agent as a biologic response modifier.

Animals↗
PubMed1990

Opposite effect of tumor necrosis factor alpha on granulocyte colony-stimulating factor and granulocyte-macrophage colony-stimulating factor-dependent growth of normal and leukemic hemopoietic progenitors.

The effect of recombinant human tumor necrosis factor alpha (TNF-alpha) on normal and chronic myeloid leukemia granulocyte-macrophage progenitors (CFU-GM) growing in semisolid agar cultures in the presence of recombinant granulocyte colony-stimulating factor and granulocyte-macrophage colony-stimulating factor was studied. Granulocyte-macrophage colony-stimulating factor-dependent growth of normal and chronic myeloid leukemia bone marrow CFU-GM was greatly enhanced by TNF-alpha at doses of 0.1 to 100 units/ml. Growth enhancement included neutrophil, eosinophil, and monocyte-macrophage colonies and clusters at 7 and 14 days of culture. Since similar results were achieved with highly enriched progenitor cell populations, devoid of accessory cells, an indirect effect on CFU-GM growth through the release by accessory cells of other cytokines upon TNF-alpha stimulation was thus ruled out. By contrast, the same doses of TNF-alpha inhibited the growth of normal CFU-GM in granulocyte colony-stimulating factor-dependent cultures. Taken together, our findings indicate that the final effect of TNF-alpha on normal bone marrow granulocyte-macrophage progenitor growth is dependent on the specific growth factor interacting with it, and that both normal and chronic myeloid leukemia CFU-GM are equally responsive to the combined effects of TNF-alpha and a given colony-stimulating factor.

Bone Marrow↗
PubMed1994

Direct and indirect effects of recombinant human granulocyte-colony stimulating factor on in vitro colony formation of human bladder cancer cells.

Although the present experimental use of recombinant human granulocyte-colony-stimulating factor (rG-CSF) has been proven to alleviate the myelosuppression induced by antitumor chemotherapy, it is also believed to stimulate growth of some nonhematopoietic tumor cells. We investigated both the direct and indirect effects of rG-CSF on in vitro colony formation of human bladder cancer cell lines using a modified human tumor clonogenic assay. Peripheral blood mononuclear cells (PBMC) were used as feeder cells (a mixture of 5 x 10(4) monocytes/dish and 5 x 10(5) lymphocytes/dish obtained from healthy donors). Human bladder cancer cell lines KK-47, TCCSUP and T24, all derived from human transitional-cell carcinomas, were incubated continuously with various concentrations of rG-CSF ranging from 0.01 ng/ml to 10 ng/ml both with and without PBMC for 7-21 days. The concentrations of rG-CSF used were chosen as being in the range of achievable serum concentrations in patients treated with rG-CSF. At the end of incubation, colonies were counted under an inverted phase-contrast microscope, and an increase in the number of colonies in comparison with the control was used to evaluate the effects of rG-CSF. Results were expressed as a percentage of controls. rG-CSF in the upper layer at concentrations ranging from 0.1 ng/ml to 10 ng/ml stimulated the colony formation of all the cancer cell lines tested in the absence of PBMC in the feeder layer, whereas cells with PBMC in the feeder layer were significantly stimulated more than those without PBMC in the feeder layer (P < 0.05) up to a certain concentration, which varied from cell line to cell line. At higher concentrations of rG-CSF, no further stimulation but, on the contrary, a decrease in colony formation was observed in cells with PBMC in the feeder layer in all the cell lines tested. Colony formation in KK-47 and T24 cell lines was significantly inhibited at 5 ng/ml and/or 10 ng/ml rG-CSF compared with cells without PBMC in the feeder layer. Our results suggest that rG-CSF may have both direct and indirect stimulatory effects on the growth of human bladder cancer cell lines in vitro. The results obtained also raise the possibility of adverse effects of rG-CSF in bladder cancer patients whose malignant cells may be directly and indirectly stimulated by this factor while it is being used clinically to alleviate the myelosuppression induced by antitumor chemotherapy.

Cell Division↗
PubMed1977

The in vitro differentiation of density sub-populations of colony-forming cells under the influence of different types of colony-stimulating factor.

The in vitro proliferation and differentiation of myeloid progenitor cells (CFU-c) in agar culture from CBA/Ca mouse bone marrow cells was studied. Density subpopulations of marrow cells were obtained by equilibrium centrifugation in continuous albumin density gradients. The formation of colonies of granulocytes and/or macrophages was studied under the influence of three types of colony-stimulating factor (CSF) from mouse lung conditioned medium CSFMLCM), post-endotoxin mouse serum (CSFES) and from human urine (CSFHu). The effect of the sulphydryl reagent mercaptoethanol on colony development was also examined. The density distribution of CFU-c was dependent on the type of CSF. Functional heterogeneity was found among CFU-c with partial discrimination between progenitor cells forming pure granulocytic colonies and those forming pure macrophage colonies. Mercaptoethanol increased colony incidence but had no apparent effect on colony morphology or the density distribution of CFU-c.

Animals↗
PubMed1995

Polymerase chain reaction for verification of fluorescent colonies of Erwinia chrysanthemi and Pseudomonas putida WCS358 in immunofluorescence colony staining.

The potential of polymerase chain reaction (PCR) for verifying the identity of colonies stained by the immunofluorescence colony-staining (IFC) procedure was investigated. Using primers directed against conserved sequences of the pectate lyase-genes coding for isozymes PLa, PLd and PLe of Erwinia chrysanthemi, the authors confirmed the identity of 96% of 20 fluorescent target colonies, punched from IFC-stained samples with pure cultures. In pour plates with mixtures of Erw. chrysanthemi and non-target colonies from potato peel extracts, the identity of 90% of 113 target colonies was confirmed. Using primers directed against sequences of the ferric-pseudobactin receptor gene pupA of Pseudomonas putida WCS358, the identity of 96% of 22 target colonies was confirmed in IFC-stained samples with pure cultures. In pour plates with mixtures of Ps. putida WCS358 and non-target bacteria from compost extracts, the identity of 59% of 108 fluorescent colonies was confirmed by PCR. It was shown that components from non-target bacteria lowered the threshold level of PCR for Ps. putida WCS358 100-fold.

Colony Count, Microbial↗
PubMed1993

Quantitative and qualitative characteristics of colony-forming unit-erythroid colonies in myelodysplastic syndrome patients.

The microcytofluorometrical method was applied to determine the relative hemoglobin (Hb) content in the bone marrow colony-forming unit-erythroid (CFU-E) colonies from 6 patients with myelodysplastic syndromes (MDS) and 10 healthy subjects. This method relies on a photochemical reaction, by which intracellular Hb is converted into fluorescent porphyrin using a 0.2 M mercaptoethylamine solution (an SH donor) and violet light (lambda = 405 nm). The relative Hb content was determined as a function of the intensity of emitted porphyrin fluorescence. The number of colonies identified by porphyrin fluorescence was smaller in MDS patients than in normal subjects. The relative Hb content was also lower in MDS patients than in normal subjects. In addition, the coefficient of variation of the relative Hb content in the CFU-E colonies was larger in MDS patients than in normal subjects. These findings suggest that colonies with low relative Hb content undergo impaired erythropoiesis and that the CFU-E colonies undergoing the impaired erythropoiesis are mixed with CFU-E colonies showing normal erythropoiesis in the bone marrow of MDS patients.

Adult↗
PubMed1999

Public health developments in colonial Malaya: colonialism and the politics of prevention.

In both African and Asian colonies until the late 19th century, colonial medicine operated pragmatically to meet the medical needs first of colonial officers and troops, immigrant settlers, and laborers responsible for economic development, then of indigenous populations when their ill health threatened the well-being of the expatriate population. Since the turn of the century, however, the consequences of colonial expansion and development for indigenous people's health had become increasingly apparent, and disease control and public health programs were expanded in this light. These programs increased government surveillance of populations at both community and household levels. As a consequence, colonial states extended institutional oversight and induced dependency through public health measures. Drawing on my own work on colonial Malaya, I illustrate developments in public health and their links to the moral logic of colonialism and its complementarity to the political economy.

Africa↗
PubMed1987

Patterns of acute myeloid leukemia colony growth in response to recombinant granulocyte-macrophage colony-stimulating factor (rGM-CSF).

In order to assess the response of acute myeloid leukemia colony-forming cells (AML-CFU) to recombinant granulocyte-macrophage colony-stimulating factor (rGM-CSF), AML blasts of 20 patients were cultured in a colony assay supplemented with titrated concentrations of rGM-CSF. In 16 cases rGM-CSF was able to induce AML colonies. In eight cases maximal clonogenic cell proliferation was obtained with 100 U rGM-CSF/ml alone (type I response). In eight other cases, however, maximal colony numbers were reached only after the addition of low concentrations of PHA-leukocyte conditioned media (PHA-LCM) to the rGM-CSF containing cultures (type II response). These values could not be obtained with higher doses of rGM-CSF (500 U/ml) or PHA-LCM separately. Thus in this subgroup, optimal AML colony formation depended on rGM-CSF plus an additional factor. Finally, in 4 of 20 cases rGM-CSF alone (100 U, 1000 U/ml) was not capable of inducing any AML colonies in vitro (type III). In these latter cases proliferation of AML-CFU could be achieved only by supplementing PHA-LCM. We conclude that GM-CSF is a stimulator of the in vitro proliferation of AML clonogenic cells. However, in a majority of these cases, i.e., 12 out of 20, AML-CFU require an additional factor for optimal proliferation which is produced by PHA-stimulated leukocytes.

Bone Marrow Cells↗
PubMed1984

Characterization of possible receptor of colony-promoting activity (CPA) by comparison with that of colony-stimulating factor (CSF).

Supernatants of long-term mouse bone marrow cell cultures contain colony-promoting activity (CPA). CPA itself does not stimulate colony formation of granulocyte-macrophage progenitor cells (GM-CFC) when added to a semisolid agar culture of bone marrow cells, but augments colony formation in the presence of colony-stimulating factor (CSF). The CPA-responsive cells are postulated to be pre-GM-CFC, a cell compartment younger than GM-CFC. In absorption experiments, CSF-coated bone marrow cells failed to absorb CPA, whereas normal bone marrow cells absorbed the activity. Cholera toxin (CT) is known to inhibit GM-CFC colony formation of bone marrow cells, probably by binding to GM-CFC-receptors [8, 9]. In the present studies, preincubation of the cells with CPA, before exposure to CT, reduced the suppressive effect of CT on GM-CFC colony formation. CT also inhibited pre-GM-CFC colony formation. Such suppressive effects, however, were reduced by preincubation of the cells not only with CPA but also with CSF. These results suggest that CSF and CPA might share the same receptors. It may also suggest that CT does not bind to specific sites. A difference in the susceptibility of GM-CFC and pre-GM-CFC to suppression by CT was also observed. Incubation of the cells with a low concentration of CT resulted in the substantial decrease of the number of GM-CFC, whereas the number of pre-GM-CFC remained high. Therefore, it seems that CPA shares some but not all of the CSF receptors.

Absorption↗
PubMed1978

Effect of myleran on murine hemopoiesis. III. Changes in the density distribution of spleen colony forming (CFU-S) and agar gel colony forming cells (CFU-C).

Spleen colony forming cells (CFU-S) and agar-gel colony forming cells (CFU-C) are separate but heterogeneous cell populations, as measured by buoyant density. Myleran (MY) abrogated the major (lighter density) components of the CFU-S and CFU-C compartments, thus shifting the surviving CFU-S and CFU-C density profiles into the higher density region. The normal spleen colony erythrocytic : granulocytic (E:G) ratio profile showed three density regions with different distributions of erythroid and granulocytic colonies. The preponderantly erythrocytic colony-generating CFU-S of the intermediate density regions were eradicated by MY. Comparison of the density distribution of erythrocytic and granulocytic colony-generating CFU-S of normal bone marrow showed that the erythrocytic CFU-S profile paralleled that of total CFU-S, while most of the granulocytic CFU-S were contained in the major (and lowest density) peak. MY eradicated the two main (and lowest density) peaks of CFU-S; surviving CFU-S occurred preponderantly in a minor (higher density) peak which has a high potential for generating erythrocytic colonies.

Animals↗
PubMed1989

Lithium stimulation of diffusion chamber colony growth is mediated by factors other than colony-stimulating factor.

Lithium is a recognized, potent stimulator of granulopoiesis. The present study used the model of clonal growth of granulopoietic precursors in diffusion chambers to investigate the relevance of certain colony-stimulating factors to lithium stimulation in vivo. In this system, lithium stimulation of granulopoiesis could not be attributed to changes in serum or chamber fluid colony-stimulating factor levels. Antibody to colony-stimulating factor-1 administered during culture markedly reduced morphologic expression of colonies in control and lithium-pretreated host mice, yet subculture of chamber contents revealed that lithium stimulation of a granulopoietic progenitor, perhaps of primitive potentiality, had nevertheless occurred. Therefore, we hypothesize that lithium acts in an indirect, hormonal fashion and that these colony-stimulating factors, while necessary for morphologic expression, play no role in the stimulatory effect. This hypothesis raises the possibility that lithium in combination with recombinant colony-stimulating factors may result in clinically effective synergistic stimulation of granulopoiesis.

Animals↗
PubMed1990

Human granulocyte colony formation in serum-free cultures stimulated with purified recombinant granulocyte colony-stimulating factor.

Granulocyte colony formation by human bone marrow cells in serum-free cultures was studied using purified recombinant granulocyte colony-stimulating factor (rG-CSF). The cloning efficiency of the serum-free cultures was about 80% that of the serum-containing cultures. In addition to purified G-CSF, four ingredients were found to be essential to granulocyte colony formation: bovine serum albumin (BSA), iron-saturated human transferrin, cholesterol, and L-alpha-phosphatidylcholine. Their optimal concentrations were also investigated. Insulin was not indispensable for granulocyte colony formation, but its addition did increase the number of granulocyte colonies. Hydrocortisone was found to be inhibitory to granulocyte colony formation at high concentrations.

Blood↗
PubMed1987

Tetrazolium staining by optical scanning overestimates colony size and number of colonies counted.

We measured the effect that staining with 2-(P-iodophenyl)-3-(p-nitrophenyl)-5-phenyl tetrazolium chloride (INT) had on the number and size distribution of tumor colonies counted using an optical image analyzer (FAS II). Staining increased the number of tumor colonies counted. By using opaque tumor cells or pigmented melanoma cells and measuring colony growth kinetics, we demonstrated that the use of INT staining to assist in counting tumor colonies artificially increased the size of viable tumor cell aggregates by adding a red precipitate to the outside surface of the cells. Laboratories that are using the INT method for drug screening are probably measuring colonies down to and below 42 microns in diameter. These small colonies could result from as few as one or two divisions. Thus, potentially useful drugs may be missed in the screen because of the presence of abortive colonies: i.e., lethally damaged cells completing only one or two divisions.

Cell Count↗