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PubMed1987

Effect of human recombinant granulocyte/macrophage colony-stimulating factor and native granulocyte colony-stimulating factor on clonogenic leukemic blast cells.

The effects of human recombinant granulocyte/macrophage colony-stimulating factor (GM-CSF) and human native purified granulocyte colony-stimulating factor (G-CSF) on the growth of clonogenic leukemic blast cells from eight Japanese patients with acute myeloblastic leukemia were studied, using an in vitro leukemic blast colony assay. The results showed that GM-CSF stimulated leukemic blast colony formation in all cases examined, whereas G-CSF stimulated colony formation in four of the eight cases. The maximum stimulating activity of GM-CSF on the growth of clonogenic leukemic blast cells was higher than that of G-CSF in the majority of cases, while sometimes GM-CSF and G-CSF worked synergistically. Thus, the clonogenic leukemic blast cell populations seemed to be heterogeneous with respect to their in vitro response to growth regulators.

Colony-Stimulating Factors↗
PubMedDate not supplied

[The stromal colony-forming cell (CFUf) count in the bone marrow of mice and the clonal nature of the fibroblast colonies they form].

The clonal nature of FCFC-derived stromal colonies was tested by chromosomal analysis in mixed cultures of CBA and CBAT6T6 bone marrow cells depleted of macrophages and myeloid cells. Inoculation of the bone marrow cell suspensions in flasks coated with poly-l-lysine has revealed practically no stromal aggregates among the explanted cells. The coincidence of karyotypes within the stromal colonies in the mixed cultures proved that the FCFC-derived colonies were cell clones. It was shown by indirect immunofluorescence with antibodies to type 1 collagen that the mouse bone marrow FCFC-derived colonies consisted of stromal fibroblasts. The cloning efficiency of the bone marrow FCFS depends on the explantation density of cells; a stable colony-forming efficiency could be reached only in the presence of feeder cells (irradiated bone marrow). In the bone marrow cells suspensions obtained by trypsinization the amount of FCFC is markedly higher than in the suspensions of mechanically disaggregated bone marrow cells.

Animals↗
PubMed1981

Hapten-specific murine colony-forming B cells. II. Delineation of a tolerogen-sensitive subpopulation of colony-forming B cells.

B cell subpopulations were studied by using B cell cloning procedures and an in vitro tolerance induction model. Fluorescein- (FL) specific B cells from normal spleens were isolated by using FL gelatin plates and were then cultured in semisolid agar in the presence or absence of tolerogen. Hapten-specific cells grew in soft agar to form discrete colonies. Colony growth is dependent on "mitogens" present in agar, sheep red blood cells (SRBC), and lipopolysaccharide (LPS). For example, SRBC plus LPS potentiate the growth of an increased number of colony-forming B cells (CFU-B) compared to either additive alone. These CFU-B could be triggered by a specific antigen to yield plaque-forming cells (PFC). With tolerogen (FL-sheep gamma-globulin) present in the agar, the number of FL-specific CFU-B was reduced by 25 to 50%. The ability of the remaining colonies to form PFC upon antigenic stimulation was also reduced. This reduction in CFU-B numbers, however, was observed only when the agar contained both SRBC and LPS as mitogenic potentiators of growth; no effect of tolerogen on CFU-B numbers was seen when cells were grown with either additive alone. Interestingly, the effect of tolerogen on CFU-B numbers was abrogated when peritoneal macrophages, in addition to SRBC plus LPS, were present during cloning. It is postulated that unique subpopulations of B cells form colonies under varied cloning conditions and that those CFU-B grown with SRBC plus LPS display an increased sensitivity to growth inhibition by tolerogen.

Animals↗
PubMed1984

Mouse B- and T-cell colony formation in vitro. I. Separation of colony-promoting and -inhibiting activities in concanavalin A rat spleen conditioned medium.

Rat spleen cell cultures exposed for 24 h to concanavalin A (Con A-CM) contain, in addition to interleukin 2 (IL-2), factors that promote colony formation in vitro by mouse T cells (TCPA) and B cells (BCPA). TCPA and BCPA are separable on a Sephadex G-75 column. TCPA has a molecular weight of 15,000 daltons and shows the same elution profile as IL-2. Absorption studies with Con A-activated T cells suggested that TCPA and IL-2 are the same entity. BCPA has an apparent molecular weight of 45,000 daltons and stimulates colony formation by B lymphocytes seeded at very low cell density (10(4) - 5 X 10(4) cells/ml). In contrast to TCPA, BCPA can only be demonstrated in gel-filtered material owing to the presence of B colony suppressor activities in crude Con A-CM. Two B colony inhibitory activities were demonstrated by AcA 34 chromatography of crude Con A-CM with molecular weights of 80,000-130,000 and about 50,000, respectively. Because of the specificity, simplicity and sensitivity of B and T colony formation these assay systems should be valuable tools for in vitro testing of biological activities regulating the immune system.

Animals↗
PubMed1984

Macrophage colony-stimulating factor and granulocyte colony-stimulating factor separated from fibrosarcoma tissue in mice.

Large increases of granulocytes and monocytes were found in the blood of mice bearing fibrosarcoma. Extraction of the tumor tissue with isotonic saline yielded a colony-stimulating factor (CSF). Further extraction of the saline-insoluble materials with 0.1% sodium dodecyl sulfate afforded another pool of CSF. Incubation of the tumor cells in vitro resulted in the accumulation of CSF activity in the culture medium. The CSF from these sources produced both granulocyte colonies and macrophage colonies in murine bone marrow cell culture. Subsequently, the activity producing granulocyte colonies was separated from that producing macrophage colonies by isoelectrofocusing and repeated gel-filtration chromatography. It was also shown that anti-L cell CSF antiserum neutralized the macrophage CSF activity but not the granulocyte CSF activity. These results show that the granulocytosis-inducing tumor produces two types of CSF.

Animals↗
PubMed1996

Macrophage-colony forming cells (M-CFC), with different sensitivities to colony stimulating factors, from peritoneal exudates and tissues of chronically inflamed mice.

OBJECTIVE AND DESIGN: To determine whether nonadherent macrophage precursors are present within the inflamed peritoneal cavity in mice, we analysed the mononuclear cell populations from different peritoneal tissues. OBJECTS: A group of 90 female mice BDF1 (C57BL/ 6 x DBA/2) was used for the study. Mononuclear cells were harvested from the peripheral blood, bone marrow, peritoneal exudate, omentum, mesentery, parietal peritoneum and diaphragm. TREATMENT: Mice were injected intraperitoneally with 0.2 ml of Freund's incomplete adjuvant. Animals were sacrificed at 6, 13, 16, 21 and 30 days. Three to six animals were examined for each time period. METHODS: Progenitor cell assay was performed in 1 ml of semi-solid agarose (0.3% Seakem GTG) DMEM which was supplied either with recombinant colony stimulating factors or with mesothelial cell-conditioned medium. RESULTS: Nonadherent macrophage-colony forming cells were present in all peritoneal compartments (35-140 precursor cells/5 x 10(4) mononuclear cells). Granulocyte/ macrophage-colony forming cells were found in the inflamed omentum. Combined simultaneous treatment with GM-CSF and M-CSF blocked the proliferation of the exudate and mesentery-derived macrophage precursors, but not other peritoneal tissue-derived macrophage precursors. Sequential stimulation with GM-CSF and M-CSF did not inhibit macrophage colony formation. CONCLUSIONS: GM-CSF can possibly influence the proliferative response induced by M-CSF. Nonadherent macrophage precursors recovered from different tissue compartments seem to differ in their sensitivity to growth regulation.

Animals↗
PubMed1997

Identification of an autocrine chondrocyte colony-stimulating factor: chondromodulin-I stimulates the colony formation of growth plate chondrocytes in agarose culture.

Chondrocytes are unique among non-transformed cells in that they are capable of anchorage-independent growth in soft agar. Fibroblast growth factor (FGF) is known as a potent colony-stimulating factor for chondrocytes. However, cartilage extracts contain a potent colony-stimulating activity which is not explicable only by contaminating FGF. We previously isolated the 25 kDa cartilage-specific glycoprotein chondromodulin-I (ChM-I) which stimulates the growth of chondrocytes. In the present study, we observed that ChM-I stimulates the colony formation of rabbit growth plate chondrocytes in agarose culture. ChM-I alone weakly stimulated the formation of chondrocyte colonies, but it markedly stimulated colony formation synergistically in the presence of an optimal dose of FGF-2. This effect was dependent on the dose of ChM-I. These results suggest that ChM-I participates in an autocrine signaling mechanism for the anchorage-independent growth of chondrocytes in vitro.

Animals↗
PubMed1983

Gonococcal pilus subunit size heterogeneity correlates with transitions in colony piliation phenotype, not with changes in colony opacity.

The apparent subunit sizes for pili of gonococci (Gc) have been visualized by using either Iodogen 125I-labeled whole Gc or immunoblotting with antipilus antiserum. These methods permitted definition of pilus subunit sizes for Gc of a given strain that had undergone changes either in piliation phenotype or in colonial opacity/protein II phenotype. The results indicate that pilus subunit size does not change coincident with changes in colony opacity/protein II phenotypes; but change in pilus subunit size is seen after a change in piliation phenotype (P+ leads to P++, and vice versa). Marked diversity in pilus subunit sizes is found for Gc of individual strains when P+ derivatives of P- colonies are compared. This diversity extends to pilus subunits of Gc found in single colonies; two distinct pilus forms were demonstrated for Gc residing in several single colonies. These findings show that Gc of a given strain are able to express any of a number of different pilus subunit size forms.

Bacterial Proteins↗
PubMed2003

Genetic diversity within honeybee colonies prevents severe infections and promotes colony growth.

Multiple mating by social insect queens increases the genetic diversity among colony members, thereby reducing intracolony relatedness and lowering the potential inclusive fitness gains of altruistic workers. Increased genetic diversity may be adaptive, however, by reducing the prevalence of disease within a nest. Honeybees, whose queens have the highest levels of multiple mating among social insects, were investigated to determine whether genetic variation helps to prevent chronic infections. I instrumentally inseminated honeybee queens with semen that was either genetically similar (from one male) or genetically diverse (from multiple males), and then inoculated their colonies with spores of Ascosphaera apis, a fungal pathogen that kills developing brood. I show that genetically diverse colonies had a lower variance in disease prevalence than genetically similar colonies, which suggests that genetic diversity may benefit colonies by preventing severe infections.

Animals↗
PubMed1983

Colony-forming lymphocytes in man. II. Increased phytohemagglutinin-induced T lymphocyte colony formation in aging humans.

Phytohemagglutinin-induced T cell colony (greater than 50 cells/aggregate) and cluster (10-50 cells/aggregate) formation was studied by one-stage microagar culture in glass capillaries by peripheral blood mononuclear cells from 26 young healthy individuals (20-32 years) and 26 aging subjects (greater than 65 years). The number of colonies developed after phytohemagglutinin (PHA) stimulation of mononuclear cells from aging subjects was significantly increased (p less than 0.05) when compared to those from simultaneously studied young individuals. Increase in the number of PHA-induced colonies by lymphocytes from aging subjects over that of young subjects was observed at different concentrations of PHA. The highest level of colony formation in mononuclear cells from both aging and young subjects was obtained with 10 micrograms/ml of PHA. Possible mechanisms for increased T cell colony formation in aging humans are discussed.

Adult↗
PubMed1982

[Colony formation of solid tumors in in vitro colony assay (human tumor stem cell assay)].

Colony forming ability of solid tumor cells was studied in a tumor colony assay (human tumor stem cell assay). In 50 cases of solid tumors, cloning efficiencies of 5 X 10(5) cells plated were as follows: breast cancer 12/12 (100%), colon cancer 10/11 (91%), ovarian cancer 9/9 (100%), sarcomas 7/9 (78%), gastric cancer 3/6 (50%), endometrial cancer 2/2 and pancreatic cancer 1/1. An overall cloning efficiency was 88% (44/50) and this rate is higher than those reported in literatures. Ovarian cancer showed the highest plating efficiency of 0.07% (number of colonies/number of cells plated X 100%) in various solid tumors tested. Subsequently, plating efficiencies of colon and breast cancer were 0.03 and 0.01%, respectively. In the cases of sarcomas and gastric cancer, low plating efficiencies were seen (0.008%, 0.003%). The overall rate succeeded colony growth of solid tumors was somewhat higher in enzymatically treated tumor cells, that is, cloning efficiencies in mechanical and enzymatic methods were 85 and 90%, respectively. The enzymatic disaggregation is an advantageous method in gastric cancer and sarcomas. Various solid tumors can be formed colonies in soft agar and chemosensitivity test using in vitro colony assay is expected in solid tumors.

Breast Neoplasms↗
PubMed1978

Studies on the morphology of colonies of bacilli of BCG-Poland substrain. I. The influence of iron on the type of BCG-Poland colonies.

The influence of iron concentration in Sauton's medium solidified with agar on the type of colonies of BCG-Poland substrains, BCG-Rio de Janeiro, BCG-France, BCG-Denmark and BCG-Japan substrains has been examined. Of all the studied BCG substrains only the BCG-Poland substrain formed rough (R) and smooth (S) colonies. In the investigated substrains rough colonies became smaller with the decrease of iron concentration but they retained their characteristic surface roughness. The smooth colonies which in the same conditions appeared only in BCG-Poland substrain did not display such dependency on iron concentration. When the incubation period was prolonged secondary rough colonies appeared among the smooth ones, regardless of the iron concentration in the medium.

BCG Vaccine↗
PubMed1996

Role of endogenous polyamines in the proliferation of normal hematopoietic progenitor cells: high-proliferative potential colony-forming cells (HPP-CFC), and low-proliferative potential colony-forming cells (LPP-CFC). Studies "in vitro".

This study concerns the role of endogenous polyamines in the proliferation of normal hematopoietic progenitor cells: high-proliferative potential colony-forming cells (HPP-CFC), and low-proliferative potential colony-forming cells (LPP-CFC) in CFW/ep mouse bone marrow cells in the agar culture system. DL-a-difluoromethylornithine (DFMO) was used as a selective and irreversible inhibitor of ornithine decarboxylase which is the first limiting step in polyamine biosynthesis. The polyamines have been implicated in cell proliferation and differentiation. The results showed that DFMO significantly inhibited the formation of LPP-CFC colonies and completely inhibited the growth of the HPP-CFC colonies. Addition of exogenous putrescine at the concentration of 10(-7) M reverses the suppressive action of DFMO in both progenitor cells. At this concentration putrescine alone had no affect on the number or the size of the colonies. It was then concluded that endogenous polyamines appear to be essential for HPP-CFC proliferation and an important requirement for LPP-CFC proliferation.

Animals↗
PubMed1992

Response of CFU-GM (colony forming units for granulocytes and macrophages) from intact and pinealectomized rat bone marrow to murine recombinant interleukin-3 (rIl-3), recombinant granulocyte-macrophage colony stimulating factor (rGM-CSF) and human recombinant erythropoietin (rEPO).

The present study provides evidence, for the first time, of a role of the pineal gland in the proliferation of CFU-GM under the influence of different cytokines. The degree of colony formation in different cytokine groups was evaluated after 24 h, 3, 7 and 10 days. The colony growth in the present type of bone marrow cell cultures slows after the 10th day and ceases after the 14th day of incubation. The results show that rGM-CSF and the combination of rGM-CSF with rIl-3 and with rEPO stimulate the colony formation of granulocytes and macrophages. A 50% general reduction in the colony number was noted in the pinealectomy group. Their pattern of response to the different cytokines was similar to that of the intact group. It is suggested that the pineal activity has a physiological role in important aspects of host defence mechanisms, such as the proliferation of CFU-GM.

Animals↗
PubMed1995

Granulocyte colony-stimulating factor and granulocyte-macrophage colony-stimulating factor in the treatment of myeloid leukemia.

Hematopoietic growth factors primarily used in patients with acute myelogenous leukemia after chemotherapy could reduce significantly the neutrophil recovery time in all patients. In high-risk acute myelogenous leukemia, trials also reported a reduction in the incidence of documented infections and early mortality rate. Thus in elderly patients with acute myelogenous leukemia and in high-risk patients with acute myelogenous leukemia the use of hematopoietic growth factors seems justified. Whether the rate of infections, particularly of life-threatening fungal infections, can be reduced by granulocyte colony-stimulating factor or granulocyte-macrophage colony-stimulating factor after chemotherapy cannot be known without larger studies. A novel strategy in the treatment of acute myelogenous leukemia is the attempt to increase the growth fraction of clonal leukemic cells prior to administration of chemotherapeutic agents by the administration of hematopoietic growth factors. Evidence shows that hematopoietic growth factors enhance anti-leukemic activity of cytosine arabinoside against leukemic cells by recruitment of leukemic cells into cell cycle, an increase of intracellular cytosine arabinoside triphosphate:deoxcytidine 5' triphosphate pool ratios, or by an enhanced cytosine arabinoside incorporation into the DNA of acute myelogenous leukemia blasts. Whether these mechanisms lead to an increase in the complete remission rate and eventually to an improvement in survival must be answered in ongoing larger acute myelogenous leukemia trials using granulocyte colony-stimulating factor or granulocyte-macrophage colony-stimulating factor in such a setting.

Acute Disease↗
PubMed1997

Role of granulocyte colony-stimulating factor and granulocyte-macrophage colony-stimulating factor in the treatment of patients with HIV infection.

The recombinant human colony-stimulating factors, granulocyte colony-stimulating factor (G-CSF) and granulocyte-macrophage colony-stimulating factor (GM-CSF) are hematopoietic cytokines that increase neutrophil number and enhance their function. In patients with HIV infection, G-CSF and GM-CSF have reversed or prevented neutropenia even during periods of full-dose myelotoxic therapy. Both colony-stimulating factors (CSFs) also have improved defects in neutrophil function in the setting of HIV infection. In non-neutropenic animal models of opportunistic bacterial or fungal infections, use of CSFs has increased survival. Future clinical applications of CSFs may include the adjunctive treatment of specific HIV-related opportunistic infections in addition to an expanding role in the treatment of HIV-associated neutropenia and defects in neutrophil function.

AIDS-Related Opportunistic Infections↗
PubMed1980

Response to treatment in acute non-lymphatic leukaemia: prognostic value of colony forming and colony stimulating capacities of bone marrow and blood cells compared to other parameters.

Growth of bone marrow and mononuclear white blood cells (MWBC) in soft-agar cultures was studied in 26 patients with untreated acute non-lymphocytic leukaemia (ANLL). Marrow and MWBC from 30 healthy volunteers served as controls. All ANLL patients revealed an abnormal growth in vitro. Patients with an increased number of clones in marrow cultures and large cluster predominance ('excessive growth') responded poorly to therapy with only one of 10 patients entering remission. On the contrary, only two of the 15 patients with a decreased clone number ('low growth') failed to achieve remission. The number of colonies and clusters in both bone marrow and blood cultures was significantly lower at presentation in patients who later entered remission than in those who did not. The correlations between the number of colonies and clusters in the blood and the marrow cultures were statistically significant. No significant correlations were found between prognosis or colony formation, on one hand, and the production of colony stimulating activity (CS)bA), by bone marrow and blood cells of ANLL patients, on the other. Nor could such correlations be found between prognosis, blood cell counts, and age. It is concluded that the growth pattero cytostatic drugs and particularly in selecting patients with a high probability to respond poorly to current cytostatic regimes.

Acute Disease↗
PubMed1996

Phase I/II study of combined granulocyte colony-stimulating factor and granulocyte-macrophage colony-stimulating factor administration for the mobilization of hematopoietic progenitor cells.

PURPOSE: To study the toxicity and efficacy of combined granulocyte colony-stimulating factor (G-CSF) and granulocyte-macrophage colony-stimulating factor (GM-CSF) administration for mobilization of hematopoietic progenitor cells (HPCs). MATERIALS AND METHODS: Cohorts of a minimum of five patients each were treated subcutaneously as follows: G-CSF 5 micrograms/kg on days 1 to 12 and GM-CSF at .5, 1, or 5 micrograms/kg on days 7 to 12 (cohorts 1, 2, and 3); GM-CSF 5 micrograms/kg on days 1 to 12 and G-CSF 5 micrograms/kg on days 7 to 12 (cohort 4); and G-CSF and GM-CSF 5 micrograms/kg each on days 1 to 12 (cohort 5). Ten-liter aphereses were performed on days 1 (baseline, pre-CSF), 5, 7, 11, and 13. Colony assays for granulocyte-macrophage colony-forming units (CFU-GM) and erythroid burst-forming units (BFU-E) were performed on each harvest. RESULTS: The principal toxicities were myalgias, bone pain, fever, nausea, and mild thrombocytopenia, but none was dose-limiting. Four days of treatment with either G-CSF or GM-CSF resulted in dramatic and sustained increases in the numbers of CFU-GM per kilogram collected per harvest that represented 35.6 +/- 8.9- and 33.7 +/- 13.0-fold increases over baseline, respectively. This increment was attributable both to increased numbers of mononuclear cells collected per 10-L apheresis and to increased concentrations of progenitors within each collection. The administration of G-CSF to patients already receiving GM-CSF (cohort 4) caused the HPC content to surge to nearly 80-fold the baseline (P = .024); the reverse sequence, ie, the addition of GM-CSF to G-CSF, was less effective. The CFU-GM content of the baseline aphereses correlated with the maximal mobilization achieved (r = .74, P = .001). CONCLUSION: Combined G-CSF and GM-CSF administration effectively and predictably mobilizes HPCs and facilitates apheresis.

Adolescent↗