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Termite colony ontogeny: a long-term assessment of reproductive lifespan, caste ratios and colony size in Reticulitermes flavipes (Isoptera: Rhinotermitidae).

Thirty Reticulitermes flavipes (Kollar) colonies established by alates collected from two separate field sites were raised in the laboratory for eight years. Twenty-one of the colonies were founded by alates from one field source and nine from another, providing demographic data from two unrelated parental lineages. Colony totals ranged from 3620 to 11641 individuals, with no significant difference in size between lineages. Soldier caste proportion of the colony total and mean wet weights for workers, soldiers and kings were significantly different between the two lineages. This suggests that at least a portion of the variability observed in caste ratios and body size may be heritable. One founding reproductive had died in five of the colonies (17%); none lost both parents. The queenless colonies contained exclusively female replacement reproductives (neotenics); the kingless colony contained a female-skewed mixture of male and female neotenics. All the nests that lost a founding parent contained significantly more pre-alate nymphs than the nests with both a king and a queen. Comparisons with published reports of ontogenetic patterns in other termites and social insects are discussed.

Animals↗

Human granulocytopoietic colonies in diffusion chambers in mice: growth of colonies and the effect of host irradiation.

Normal human non-separated bone marrow cells were cultured in fibrin clots in diffusion chambers implanted intraperitoneally in mice, and harvested at different intervals by a previously described chamber centrifugation technique. This method demonstrates the presence of cell aggregates in the diffusion chambers. When the chambers are implanted in irradiated mice (450 R) and retransplantated into newly irradiated mice every seventh day, a continous increase in number of cells per granulocytopoietic aggregate is observed from day 8 to day 21. This is compatible with the view that the aggregate is observed from day 8 to day 21. This is compatible with the view that the aggregates are colonies. The term 'colony forming unit diffusion chamber' (CFUD) is suggested to denote the ancestor(s) of the colonies. However, formal proof that one colony is derived from one cell is lacking. Preirradiation of mice with 450 R significantly increases the number of neutrophilic granulocytopoietic colonies at day 14, provided the chambers are retransplantated to newly irradiated mice at day 7, indicating that the neutrophilic colony forming unit or its progeny is involved as at least one of the targets of the stimulating effect of host irradiation. In contrast, no effect of host irradiation on the numbers of eosinophilic colonies was observed.

Adult↗

The statistical distribution of colony counts in the spleen colony assay.

The statistical distribution of colony counts in the spleen colony assay was determined in C57BL/6 and C3H mice under varying conditions of the assay procedure. Assay mice were given syngeneic bone marrow cells from normal or irradiated donors. The mice were injected intravenously with marrow cells either immediately or 3 days after irradiation. Eight days after engraftment, spleen colonies were counted and the statistical distribution of colony counts was determined using a mean to variance ratio criterion. Analysis of the data indicated that the statistical distribution of colony counts was different in the two strains of mice. In addition, delaying time of injection of mice with bone marrow cells or injecting bone marrow cells form irradiated donors also changed the statistical distribution. The significance of this work lies in the fact that modification of the usual assay procedure can alter the statistical distribution of colony counts, thus changing the statistical accuracy of the assay. Modification in the assay procedure, such that an increase occurs in the variance of the distribution of colony counts, must be compensated for by increasing the number of spleens counted in order to maintain a constant level of statistical accuracy in experiments.

Animals↗

Characterization of in vitro T lymphocyte colonies from normal mouse spleen cells: colonies containing cytotoxic lymphocyte precursors.

The functional activity of T cell colonies grown from normal murine spleen cells has been examined. Up to 75% of the T cell colonies contain cytotoxic lymphocyte precursors (CLP). One out of three colonies contains CLP, which can respond to a given foreign H-2 haplotype. The CLP from the T cell colonies appear identical to the CLP in lymph node tissues in their degree of cross-reactivity and requirement for accessory cells. The effector cells produced were shown to be T lymphocytes. Karyotypic analysis of the cells in colonies grown from a mixture of T6-marked and normal spleen cells indicated that individual colonies were formed from an initial small aggregate of cells. Radiation survival data indicated that the colony-forming unit contains three or fewer proliferating cells.

Animals↗

Human T-lymphocyte colonies: generation of colonies in different lymphocyte subpopulations.

The generation of human T-lymphocyte colonies from different lymphocyte subpopulations in the presence of PHA alone, or PHA plus media conditioned by PHA-stimulated lymphocytes (PHA-LCM) has been investigated. The separation technique consisted of phagocytic cell depletion by carbonyl iron treatment and fractionation of non-phagocytic cells (NP cells) into B cells and T + null cells by affinity chromatography on an anti-F(ab')2 column. The T cells were separated from the null cells by E-rosette sedimentation. Under these conditions, we showed that: no T-lymphocyte colonies were obtained from the null-cell subset in the presence of PHA of PHA + PHA-LCM; T-lymphocyte-colony formation potential was retained in the T-cell subset. Some variability was observed in the production of T colonies using peripheral blood lymphocytes (PBL) from different donors. Low producers and high producers of T-lymphocyte colonies were encountered. The low production of T-lymphocyte colonies observed in some donors was due to a suppressive effect mediated by the phagocytic cells, probably monocytes. The anti-F(ab')2 immunoadsorbent retained a cell population necessary for T-lymphocyte colony growth.

Adult↗

Comparative studies of the colony-promoting activity of porcine kidney extract with several interleukins and colony-stimulating factors.

Porcine kidney extracts (PKE) possess colony-promoting activity (CPA) which stimulates primitive hematopoietic cells in the presence of granulocyte/macrophage colony-stimulating factor (GM-CSF), but PKE itself does not stimulate colony formation on murine bone marrow cells. We have compared the CPA of PKE with that of recombinant cytokines or CSFs such as interleukin-1 alpha (IL-1 alpha), IL-3, IL-6, granulocyte colony-stimulating factor (G-CSF), GM-CSF and macrophage colony-stimulating factor (CSF-1). All of these factors were less potent than PKE. Furthermore, the combinations of IL-1 alpha or PKE with G-CSF, GM-CSF, IL-3 or IL-6 were examined in the presence of one of these factors such as CSF. It is found that PKE acts synergistically with G-CSF, GM-CSF, IL-3 and IL-6, showing enhancement ratios of 10, 2.5, 4.2 and 30, respectively. The combination of IL-1 alpha resulted in poor colony formation in contrast with those of PKE, except for CSF-1. These results suggest that the CPA of the factor(s) in PKE differ from the cytokines and CSFs tested in this study, and is significantly affected by various types of CSF.

Abdominal Muscles↗

Stimulatory effects of granulocyte colony-stimulating factor on colony-forming units-spleen (CFU-S) differentiation and pre-CFU-S proliferation in mice.

Granulocyte colony-stimulating factor (G-CSF) was reported to increase the number of colony-forming units-spleen (CFU-S) and multilineage colonies as well as myeloid-committed cells. We investigated the effects of G-CSF on myeloid progenitors and primitive stem cells in a mouse bone marrow transplantation (BMT) system. Lethally irradiated mice received BM cells from untreated or 5-fluorouracil-treated mice, and then were administered G-CSF or carrier buffer (control) for 5 days from immediately after BMT. A pre-CFU-S assay was performed by the repeated transplantation of BM cells from the first BMT recipients to other mice. By the method of polymerase chain reaction, most of the spleen colonies in the secondary recipients were confirmed to be derived from the first donors. G-CSF did not increase the peripheral white blood cell count significantly, but did increase the number of immature myeloid cells and granulocyte-macrophage colony-forming cells in the BM. The number of erythroid cells in the BM was initially suppressed and then increased by G-CSF treatment. In addition, the pre-CFU-S assay showed an increase in pre-CFU-S cells due to G-CSF administration. The number of spleen colonies of first BMT recipients did not increase, but a higher percentage of them were committed to a certain lineage by G-CSF treatment. These findings suggest that G-CSF has important roles in the early stages of hematopoiesis.

Animals↗

Hemopoietin-1 activity of interleukin-1 (IL-1) on acute myeloid leukemia colony-forming cells (AML-CFU) in vitro: IL-1 induces production of tumor necrosis factor-alpha which synergizes with IL-3 or granulocyte-macrophage colony-stimulating factor.

Interleukin-1 (IL-1) has hemopoietin-1 (H-1) activity, i.e., it synergizes with macrophage-colony stimulating factor (M-CSF), granulocyte-macrophage-CSF (GM-CSF) and interleukin-3 (IL-3) in stimulating in vitro colony formation of hematopoietic progenitor cells. In this study the synergistic activity of IL-1 was investigated on IL-3 and GM-CSF induced growth of acute myeloid leukemia colony forming cells (AML-CFU) in vitro. Among 12 cases of human AML, IL-1 significantly elevated IL-3 stimulated colony numbers in eight instances and enhanced GM-CSF induced colony growth in five cases. As IL-1 is an inducer of cytokine production and since tumor necrosis factor (TNF) elevates IL-3 or GM-CSF induced proliferation of AML-CFU, we examined whether IL-1 enhanced AML-CFU growth via the induction of TNF production. Neutralizing anti-TNF-alpha antibodies significantly decreased IL-1/IL-3 or IL-1/GM-CSF stimulated colony numbers in six of seven cases studied, whereas anti-TNF-beta had no effect, indicating that endogenously produced TNF-alpha costimulated the growth of AML-CFU. Furthermore, AML blast cells stimulated by IL-1 released increased amounts of TNF-alpha (between 25 and 533 pg/ml; median 255 pg/ml) into the culture medium (TNF-alpha specific radioimmunoassay) as compared with noninduced AML cells (less than 1 to 149 pg TNF-alpha/ml; median 31 pg/ml). Thus, the effect of IL-1 on AML-CFU proliferation is not the result of direct activation of AML progenitors, but IL-1 stimulates the release of TNF-alpha by AML cells and endogenous TNF subsequently synergizes with IL-3 or GM-CSF.

Antibodies↗

Lineage commitment of hemopoietic progenitor cells in developing blast cell colonies: influence of colony-stimulating factors.

In clonal cultures of normal mouse marrow cells, combination of granulocyte, granulocyte-macrophage, or multipotential colony-stimulating factor (G-CSF, GM-CSF, or multi-CSF, respectively) with stem cell factor (SCF) did not alter the number of blast colonies stimulated to develop compared with SCF alone but induced an up to 25-fold increase in their mean cell content and an up to 6-fold increase in their mean progenitor cell content. Costimulation of blast colony formation by SCF plus G-CSF did not change the relative frequency of progenitor cells of different types within the colonies compared with colonies stimulated by SCF alone. However, combination of GM-CSF or multi-CSF with SCF significantly increased the relative frequency of granulocytic progenitors and, for multi-CSF, also of eosinophil progenitor cells. These changes in the relative frequencies of progenitor cells committed to the various lineages support the hypothesis that hemopoietic regulators have some ability to induce selective lineage commitment in the progeny of multipotential cells.

Animals↗

Incidence and characteristics of colony-forming units fibroblasts (CFU-F) in the bone marrow of weanling mice treated with cytosine arabinoside and phenylhydrazine: correlation with CFU-S, progenitors of diffusion-chamber colonies (CFU-D), and CFU-C.

A study of murine adherent marrow cells (AMC) under conditions of high and low concentrations of hematopoietic stem cells and progenitors was carried out. In one group of weanling mice, decreased marrow cellularity and increased concentrations of CFU-S, CFU-D, and CFU-C were observed two days after administration of two consecutive intraperitoneal (i.p.) cytosine arabinoside (Ara-C) injections (2 x 200 ng/kg, at 6 h interval). Fibroblast colony-forming units (CFU-F) of this marrow were studied. In a second group of mice, which were given three i.p. phenylhydrazine (PHZ) injections (3 x 60 mg/kg on days 0, 1, and 3), CFU-S and CFU-C levels were unchanged or lowered 6 days after the start of PHZ administration. In these animals, however, the number of CFU-D was four times higher than in controls. The study of CFU-F in experiments of groups 1 and 2 indicated a high concentration of these progenitors in group 1 and lower concentration in group 2. Furthermore, fibroblastoid colonies produced in vitro by CFU-F of Ara-C-treated marrow were significantly larger than colonies from control marrow, and they markedly inhibited G/M colonies in split-phase agar cultures. By contrast, fibroblastoid colonies produced by PHZ-treated marrow were of regular size and did not inhibit G/M colonies from test bone marrow.

Animals↗

Radioresistant pseudo-colony formation in the PHA-leukocyte feeder colony assay.

In the PHA-leukocyte feeder colony assay--a fluid assay on top of an agar underlayer--colonies might not be the product of clonogenic cells but rather from aggregates, as was already shown for hairy cell leukemia (Leukemia Res. 11, 911 (1987)). To study the role of aggregation in this colony assay in other B-cell malignancies, we irradiated cells from B-chronic lymphocytic leukemia, B-non-Hodgkin's lymphoma and multiple myeloma. In nearly all cases, viable "colonies" were seen after irradiation, albeit in lower numbers. These data indicate that in the PHA-leukocyte feeder colony assay, a considerable percentage of colonies from a large variety of B-cell malignancies originate from aggregating rather than from proliferating cells.

B-Lymphocytes↗

Growth of macroscopic human megakaryocyte colonies from cord blood in culture with recombinant human thrombopoietin (c-mpl ligand) and the effects of gestational age on frequency of colonies.

We investigated the effects of recombinant human thrombopoietin (rhTPO) on the growth of megakaryocytic (MK) colony derived MK progenitors from human cord blood (CB) in vitro and the effects of gestational age on the number of MK colonies. The results demonstrated that rhTPO alone supports the growth of MK colonies and induces not only proliferation but also differentiation of MK progenitors. CB shows a high frequency of MK colonies; most of which are very large and equivalent to high proliferative potential colony-forming unit-megakaryocyte. The colonies could be macroscopically observed as white spots in the culture dish. Preterm neonates showed greater numbers of MK progenitors than term neonates and there was an inverse correlation between gestational age and concentration of MK progenitors of CB. The effects of gestational age was an important factor on the proliferative capacity of MK progenitors and on the response to rhTPO.

Cell Culture Techniques↗

Task Partitioning in Insect Societies. I. Effect of Colony Size on Queueing Delay and Colony Ergonomic Efficiency.

The collection and handling of colony resources such as food, water, and nest construction material is often divided into subtasks in which the material is passed from one worker to another. This is known as task partitioning. When material is transferred directly from one individual to another, queueing delays frequently occur because individuals must sometimes wait for a transfer partner. A stochastic simulation model was written to study the effect of colony size on these delays. Queueing delay decreases roughly exponentially with colony size because stochastic fluctuations in the arrival of individuals are lower in larger colonies. These results support empirical studies of Polybia occidentalis and other theoretical studies of honeybees. The effect of the relative number of individuals in the two subtask groups was also studied. There is a unique optimal ratio of the number of workers associated with each of the subtasks that simultaneously minimizes mean queueing delay and maximizes colony nectar-processing rate. Deviations from this optimal ratio, for example, as a result of forager mortality or changes in nectar productivity that affect foraging trip duration, increase mean queueing delays greatly, especially in smaller colonies.

colony size↗

The effect of cyclic AMP on human colony forming cell and colony stimulating factor production.

The effect of cyclic AMP (cAMP) and related nucleotides on human colony forming cells (CFC) and those cells producing colony stimulating factor (CSF) was studied in vitro. When added at physiological concentrations (10(-2) to 1 micron), exogenous cAMP stimulated maximum colony formation in cultures without feeder layers. Related nucleotides stimulated colony formation to a lesser extent and in decreasing order of free energy. All nucleotides inhibited colony formation in concentrations above 1 micron. A velocity sedimentation cell separation technique was used to obtain cell fractions rich in CFC but poor in CSF-producing cells. Such fractions did not respond to cAMP stimulation. These studies suggest that exogenous cAMP stimulates human bone marrow to form colonies in vitro by increasing the release and/or production of endogenous CSF.

Adenine↗

Purification of human marrow progenitor cells and demonstration of the direct action of macrophage colony-stimulating factor on colony-forming unit-macrophage.

To facilitate the investigation of the direct interaction between hematopoietic progenitors and colony-stimulating factors, we have developed a method to purify human marrow progenitor cells. Using density centrifugation, negative panning with concanavalin A coated plates, positive selection of CD34-positive cells with immunomagnetic microspheres, overnight adherence to a plastic dish, negative selection with a panel of monoclonal antibodies, and density centrifugation, human marrow progenitor cells were purified from 1.5% to 53.2%, a 42-fold purification, with a 4.8% yield. The purified cells consisted of 38% erythroid, 9% colony forming unit-granulocyte (CFU-G), 29% CFU-macrophage (CFU-M), 12% CFU-eosinophil/basophil (CFU-Eo/Ba), and 4% CFU-mix. The purified cells cultured in serum-free fibrin clots with recombinant human macrophage colony-stimulating factor (rM-CSF) for 14 days developed a pure population of CFU-M colonies. An appearance of CFU-M colonies was present after the addition of 1 U/mL of rM-CSF and the maximum stimulation was found at 100 U/mL. When the purified cells were cultured in serum-free medium with rM-CSF in a limiting dilution assay and the percentage of nonresponder wells for CFU-M colonies was plotted against cell concentration, serum-free cultures yielded a straight line through the origin, indicating that CFU-M development did not depend on accessory cells and that rM-CSF acted directly on the CFU-M.

Antigens, CD↗

Bovine granulocyte/macrophage and erythroid colony culture: characteristics of the colonies and the assay systems.

Bovine bone marrow granulocyte/macrophage colonies were cultured in vitro in methyl cellulose and in plasma clots using bovine endotoxin-stimulated serum as a source of colony stimulating activity. The endotoxin-stimulated serum was four times as potent as the control serum in the methyl cellulose cultures. No significant increase in the number of colony forming units was observed when bovine marrow cells were maintained in suspension cultures for various periods prior to plating in methyl cellulose. The percentage of glass/plastic adherent cells in bovine marrow cells was observed to be 43% +/- 12 (SD). Benzidine positive erythroid colonies appeared in plasma clot cultures on day 4 and disappeared by day 9. No second population of erythroid colonies appeared either as a function of time or as a function of erythropoietin concentration. The optimum erythropoietin concentration for bovine erythroid cultures was found to be 1.0 unit/mL. A significant difference was observed between animals in their marrow capacity to produce erythroid colonies in culture but no significant difference was observed within individual animals over a period of three months.

Animals↗

Lymphokine(s) from isolated T lymphocyte subpopulations support multilineage hematopoietic colony and megakaryocytic colony formation.

Conditioned medium derived from peripheral mononuclear low-density cells stimulated with phytohemagglutinin (PHA) supports the growth of noncommitted hematopoietic progenitors from marrow and peripheral blood cells. These immature progenitors (CFU-GEMM) can be identified in culture as multilineage hematopoietic colonies containing erythroblasts, eosinophilic, basophilic and neutrophilic granulocytes, megakaryocytes, macrophages, and T and B lymphocytes. In this report, we describe the effect of lymphokines released from purified T lymphocyte preparations of helper (T4) and suppressor/cytotoxic (T8) phenotype derived from peripheral blood on the growth of multilineage hematopoietic colonies and megakaryocytic colonies. It was found that PHA-stimulated lymphocytes of T4 phenotype and, to a lesser extent, of T8 phenotype elaborate lymphokine(s) that support the growth and development of multilineage colonies (CFU-GEMM), granulopoietic colonies (CFU-C), erythroid bursts (BFU-E) and megakaryocytic colonies (CFU-M) by nonadherent and T cell-depleted bone marrow cells.

Animals↗

The role of erythropoietin, megakaryocyte colony-stimulating factor, and T-cell-derived factors on human megakaryocyte colony formation: evidence for T-cell-mediated and T-cell-independent stem cell proliferation.

Recent studies suggest that megakaryocytopoiesis is governed by a dual-level regulatory process, with megakaryocyte colony-stimulating factor (Meg-CSF) primarily influencing proliferation of the committed precursors and thrombopoietin required for megakaryocyte ploidy amplification and for maturation. The authors have examined different sources of Meg-CSF in a microagar culture system with a view to their capacity to enhance megakaryocyte colony formation directly or via an indirect T-lymphocyte- or monocyte-mediated effect. The comparative influences of phytohemagglutinin-stimulated leukocyte-conditioned medium (PHA-LCM), erythropoietin (Epo), sera of patients with severe aplastic anemia, and direct PHA addition to the culture were evaluated for their capacity to enhance megakaryocytic colony formation as well as for the maturation rate of megakaryocytes (Mk) grown in our microagar culture system. Each treatment by itself enhanced colony formation from unseparated low-density cells. Removal of T-lymphocytes and monocytes from the bone marrow sample caused a cessation of the enhancing effect of direct PHA addition to cultures stimulated with Epo, but did not influence the enhancing activities of severe aplastic anemia serum (SAA), PHA-LCM, and Epo. The results show that SAA serum, Epo, and PHA-LCM induced Mk colony formation directly and therefore may act via a common mechanism. Differences, however, were observed concerning their colony-stimulating potency and their influence on the Mk maturation rate.

Anemia, Aplastic↗