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PubMed1991

Megakaryocyte potentiating activity of IL-1, IL-6 and GM-CSF as evaluated by their action on in vitro human megakaryocytic colonies.

We examined whether recombinant cytokines enhance the in vitro platelet production of interleukin-3 (IL-3)-induced human megakaryocytic colonies (Meg-colony). We classified Meg-colonies into four categories based on platelet production during in situ observation on day 14: type 0, absence of cytoplasmic processes in a colony; type 1, one to three processes in at least one megakaryocyte in a colony; type 2, four to eight processes; type 3, more than nine processes or division of cytoplasm. Type 3 colonies were considered to be platelet-producing. In control cultures, type 1 Meg-colonies were dominant, followed by type 2, type 3 and type 0. Of the cytokines added at the initiation of culture, interleukin-1 alpha (IL-1 alpha), interleukin-6 (IL-6), and granulocyte/macrophage colony stimulating factor (GM-CSF) significantly increased the number of colonies. Furthermore, these three cytokines significantly elevated the proportion of type 3 colonies. Interleukin-4 (IL-4), granulocyte-CSF, macrophage-CSF and erythropoietin did not affect the colony count or distribution of colony type. IL-1 alpha, IL-6 and GM-CSF also significantly elevated the proportion of type 3 colonies, even when added to the culture on days 8 or 11. These results indicate that IL-1 alpha, IL-6 and GM-CSF promote platelet production of in vitro Meg-colonies.

Blood Platelets↗
PubMed1984

A model of intramedullary hematopoietic microenvironments based on stereologic study of the distribution of endocloned marrow colonies.

Hematopoietic colonies were studied in the marrow of alternate fraction-irradiated mice by light microscopic stereology to investigate the microenvironmental organization of marrow. Separate analyses of the relative colony cell density of undifferentiated, granulocytic, erythrocytic, and macrophage colonies in four marrow zones were carried out at 3, 4, and 5 days postirradiation (PI) for all colonies, all periarterial colonies, and all non-periarterial colonies. The results demonstrate a differential colony cell distribution that does not appear to be due to a preferential distribution of certain colony types around arteries. Undifferentiated colony cells showed a consistent predilection for endosteal and periarterial regions, with the majority of colony cells occurring along bone. Erythrocytic colony cells proliferated initially in intermediate and central marrow zones and along arteries. Granulocytic colony cells occurred in all areas at 3 days PI, but increased in density along bone thereafter. Macrophage colony cells occurred in all zones at 4 days PI, but at 5 days were concentrated in subosteal and central regions. Macrophage colonies also occurred periarterially. To explain these findings and the organization of normal bone marrow, we present a detailed model of the microenvironmental organization of intramedullary hematopoiesis. This model portrays the stroma as engendering distinct microenvironments for stem cell replication, stem cell commitment, and early progenitor cell proliferation.

Animals↗
PubMed1982

Clonal origin of murine hemopoietic colonies with apparent restriction to granuclocyte-macrophage-megakaryocyte (GMM) differentiation.

We characterized murine hemopoietic colonies consisting of granulocytes, macrophages, megakaryocytes, and blast cells and yet lacking erythroid elements. Mouse marrow or spleen cells were cultured in methylcellulose media in the presence of 10% (v/v) pokeweek mitogen-stimulated spleen cell-conditioned medium (PWM-SCM) and 2 units/ml erythropoietin for 8 days. Granulocyte-macrophage-megakaryocyte (GMM) colonies could be distinguished from granulocyte-erythrocyte-macrophage-megakaryocyte (GEMM) colonies because the former lacked the typical appearance of bursts with red color. Analysis of Y-chromosomes in mixing experiments with male and female marrow cells confirmed the clonal nature of the GMM colonies. Differential counts of GMM colonies revealed varying, but significant, numbers of blast cells in all of the day-8 and day-12 colonies and in seven out of ten day-14 GMM colonies. In general, the percentages of blast cells were inversely related to the length of incubation in culture. Replating experiments confirmed the absence of late erythroid precursors such as CFU-E and normoblasts in all of the 50 day-8 GMM colonies. However, six out of the 50 GMM colonies contained early progenitors capable of erythroid expression, such as BFU-E, CFU-EM, CFU-GEM, and CFU-GEMM. In contrast, the three day-14 GMM colonies which did not reveal blast cells failed to produce secondary colonies. Thus, while the progenitors for the latter colonies are restricted to only granulocyte-macrophage-megakaryocyte differentiation, some of the apparent GMM colonies containing blast cells may have originated in early progenitors close to pluripotent stem cells. Detailed cytological analyses and replating experiments are necessary for characterization of true differentiation potentials of mixed colonies in culture.

Animals↗
PubMed2000

Colony sound facilitates sexual and agonistic activities in royal penguins.

A unique playback system was used to exaggerate continuously the number of calls heard in royal penguin, Eudyptes schlegeli, colonies to determine whether social facilitation increases a female's exposure to both sexual and agonistic activities, a process that could influence the timing of reproduction in colonies. We also determined whether the source of colony sound or the phase of the breeding cycle influenced the facilitation of sexual or agonistic activities. The system recorded and then played a new 12-min colony sound sample every 24 min throughout the first four phases of the breeding cycle. Because each broadcast was unique, this playback system avoids the possibility of habituation and can modify the acoustic environment in social groups for extended periods of time. The activities of penguins in control colonies (with no playback) were compared with those in colonies that heard samples derived from either their own or a different colony. Colony sound facilitated both sexual and agonistic activities from male and female royal penguins during all four phases of the cycle that we examined. Playbacks from the perceiver's own colony facilitated a greater response than sound originating from a different colony. Studies comparing egg-laying dates in colonies exposed continuously to the sounds of agonistic activities with those in control colonies, or colonies exposed continuously to the sounds of sexual activities are now needed to determine whether the facilitation of agonistic activities opposes the effects of social stimulation on the hormonal changes leading to ovulation in colony-dwelling birds. Copyright 2000 The Association for the Study of Animal Behaviour.

Journal Article↗
PubMed2002

Sex-ratio dependent execution of queens in polygynous colonies of the ant Formica exsecta.

Formica exsecta has become an important model system for studying intraspecific variation in sex ratios. Patterns of sex allocation in polygynous (multiple queen per nest) populations of F. exsecta are generally consistent with the queen-replenishment hypothesis. This hypothesis states that colonies produce gynes (reproductive females) in order to increase queen number and enhance colony survival and/or productivity when the number of resident queens is low. However, the small proportion of colonies that raise gynes produce more than necessary for simple queen replenishment. It has been hypothesized that excess production of gynes may occur to reduce the frequency of accepting foreign unrelated gynes into the colony when workers cannot distinguish nestmate from non-nestmate queens. This explanation for excess gynes requires weak or no aggression between non-nestmates and is expected to lead to the selective execution of new queens by colonies that do not invest in the production of gynes. Experimental studies where gynes were introduced into natal and foreign colonies indeed suggested that polygynous populations of F. exsecta have a poor nestmate recognition system. Although gynes were significantly more likely to be accepted in their parental colony compared to another foreign female-producing colony, the difference was small. Moreover, encounters between workers from different colonies within the population showed very little aggression and were no more aggressive than encounters between nestmates, again suggesting a weak capacity for nestmate recognition. Our experiment also showed that colonies that produced only males executed most of the gynes that were experimentally introduced into the colony, whereas female-producing colonies accepted most gynes. This is consistent with ants using a simple rule of thumb to decrease parasitism by unrelated queens, whereby colonies selectively destroy gynes whenever gynes are not produced in the colonies.

Aggression↗
PubMed2005

Transmission of Vairimorpha invictae (Microsporidia: Burenellidae) infections between red imported fire ant (Hymenoptera: Formicidae) colonies.

Red imported fire ant, Solenopsis invicta, colonies were successfully infected with the microsporidium Vairimorpha invictae by introducing live larvae, pupae, or dead adults from V. invictae-infected field colonies collected in Argentina. Introductions with 4th instar larvae or non-melanized pupae obtained from infected field colonies, resulted in infection of 40% of the inoculated colonies. Introductions of 4th instars or melanized pupae produced from colonies that were initially infected in the laboratory, resulted in infections of 83% of the colonies, thus perpetuating the infection in other colonies. Infection was detected in 2 of 6 colonies after introducing adult worker caste ants that had died with V. invictae. The average number of adults and the volume of immature ants per colony were significantly lower in the infected than in the control colonies. Infected colonies had 86% fewer adults per colony and 82% less immature ants than the controls. A portion of the 16S rRNA gene of the V. invictae identified from these studies was amplified, cloned, and sequenced; the 1251 nucleotide amplicon was 100% identical to the 16S rRNA gene sequence recorded previously in the GenBank database, thus verifying the species as V. invictae. This is the first report of the artificial transmission of this pathogen to uninfected ant colonies, and demonstration of its ability to hinder growth in individual colonies.

Animals↗
PubMed1982

The psychology of colonialism: sex, age, and ideology in British India.

It is becoming more and more obvious that colonialism--as we have come to know it during the last two hundred years--cannot be identified with only economic gain and political power. In Manchuria, Japan consistently lost money, and for many years colonial Indochina, Algeria and Angola, instead of increasing the political power of France and Portugal, sapped it. This did not make Manchuria, Indochina, Algeria or Angola less important as colonies. Nor did it disprove the point that economic gain and political power are important motives in a colonial situation. It only showed that colonialism could be characterized by the search for economic and political advantage without concomitant real economic or political gains, and sometimes even with economic or political losses. This essay argues that the first differentia of colonialism is a state of mind in the colonizers and the colonized, a colonial consciousness which includes the sometimes unrealizable wish to make economic and political profits from the colonies, but other elements, too. The political economy of colonization is of course important, but the vulgarity and insanity of colonialism are principally expressed in the sphere of psychology. The following pages will explore some of these psychological contours of colonialism in the rulers and the ruled and try to define colonialism as a shared culture which may not always begin with the establishment of alien rule in a society and end with the departure of the alien rulers from the colony. The example I shall use will be that of India, where a colonial political economy began to operate seventy-five years before the full-blown ideology of British imperialism became dominant, and where thirty years after the formal ending of the raj, the ideology of colonialism is still triumphant in many sectors of life.

Cultural Characteristics↗
PubMed1993

Intercellular communication in colonies of Syrian hamster embryo cells and the susceptibility for morphological transformation.

The levels of gap junctional intercellular communication (GJIC) were studied in normal, morphologically altered and morphologically transformed colonies formed in the Syrian hamster embryo (SHE) cell transformation assay. The colonies were selected from non-exposed dishes or dishes exposed to 12-O-tetradecanoylphorbol-13-acetate (TPA, 0.16 microM), di(2-ethylhexyl)phthalate (DEHP, 77 microM), Na-orthovanadate (vanadate, 3.4 microM) or dieldrin (25 microM) for 7 days during colony formation. TPA, DEHP and vanadate induced increased frequencies of morphological transformation of colonies. At the same time, TPA and DEHP decreased GJIC in the colonies by approximately 30% under the conditions used. All categories of colonies were equally affected. Vanadate did not change the level of GJIC in any of the categories of colonies compared to unexposed control. Dieldrin strongly suppressed GJIC in all colonies without increasing the frequency of transformation. The compounds affected GJIC after short-term exposures (4 and 24 h) to cell monolayers rather similarly to that found after long-term exposure to the colonies. Transformation assays with coexposure of dieldrin together with the transforming agents vanadate, DEHP or benzo[a]pyrene did not increase transformation frequencies compared to the transforming agents alone. The GJIC level in all coexposure groups was similar to that of dieldrin alone. Furthermore, regardless of whether dieldrin was present or not, removal of vanadate 24 h before fixation of the colonies caused a slight decrease in the transformation frequency. The results suggest that: (i) morphologically transformed colonies have the same ability of intercellular communication as normal colonies; (ii) decreased GJIC is probably not either sufficient or necessary to induce transformation of SHE cell colonies; (iii) a decreased level of GJIC does not necessarily increase the susceptibility of SHE cells for transformation; and (iv) inhibition of GJIC may not have an impact on the maintenance of the transformed phenotype of SHE cell colonies.

Animals↗
PubMed2003

Nutritional ecology of the Formosan subterranean termite (Isoptera: Rhinotermitidae): growth and survival of incipient colonies feeding on preferred wood species.

The wood of 11 plant species was evaluated as a food source significantly impacting the growth and survival of incipient colonies of the Formosan subterranean termite, Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae). Colonies of C. formosanus feeding on pecan, Carya illinoensis (Wangenh.), and red gum, Liquidambar styraciflua L., produced significantly more progeny than colonies feeding on other wood species tested. Progeny of colonies feeding on pecan and American ash, Fraxinus americana L., had significantly greater survival than progeny of colonies feeding on other wood species. Colonies feeding on a nutritionally supplemented cellulose based matrix showed similar fitness characteristics as colonies feeding on the best wood treatments. These results indicate that differences observed in colony fitness can be partially explained by nutritional value of the food treatment, raising the possibility that wood from different tree species have different nutritional values to the Formosan subterranean termites. Colonies feeding on loblolly pine, Pinus taeda L., and ponderosa pine, Pinus ponderosa Laws., had significantly lower survival and produced significantly fewer workers and soldiers than colonies feeding on other wood species. Colony survival from 90 to 180 d of age and from 90 to 360 d of age was significantly correlated with the number of workers present at 90 d of colony age, indicating that colony survival depends on the presence of workers. Wood consumption in a multiple-choice study was significantly correlated with colony fitness value. This suggests that feeding preference of C. formosanus is at least partially influenced by the nutritional value of the food source.

Animal Nutritional Physiological Phenomena↗
PubMed1986

Relationship between IL-2 and human T cell colony formation.

We have tested the reliability of a standard IL-2 microassay (3H-thymidine uptake by IL-2-dependent T cell lines) as a measure of the colony promoting activity (CPA) required for PHA-induced T cell colony growth in semi-solid cultures. Colonies were obtained from freshly isolated mononuclear cells (PBL) (primary colonies) or pooled cells of primary colony (secondary colonies). PHA-stimulated PBL generated primary colonies in the absence of exogenous CPA which, however, when added to the cultures enhanced colony growth. In contrast, primary colonies failed to form PHA-induced secondary colonies in the absence of exogenously supplied CPA. There was a close correlation between the colony forming capacity of PBL and primary colonies from the same donors plated in the presence of added CPA (r = 0.98). When CPA was measured in the secondary colony growth assay and the data compared to IL-2 measurement in the standard IL-2 microassay, CPA and IL-2 levels did not correlate, suggesting that IL-2 and CPA may represent distinct factors. The usefulness of primary colonies as target cells for the measurement of CPA levels in a variety of conditioned media is discussed.

Cell Division↗
PubMed1984

Quantitation of the number of cells within tumor colonies in semisolid medium and their growth as oblate spheroids.

The number of cells within tumor colonies has not been determined accurately in prior reports because, in all but small clusters, cells grow too closely and stacked to allow direct counting of cells by inverted microscopy. Therefore, we stained colonies formed in agar from 38 tumor cell samples of diverse histological origin, removed them with a micropipet, and directly counted the number of cells. The number of cells within colonies increased geometrically with colony diameter and inversely with the size of the cells within the colonies. The relationship can be described using linear regression: [In(no. of cells/colony) = 0.87 - 2.80 In (colony cell diameter) + 2.38 In (colony diameter)] which gave an R2 of 0.92. Measurements of colonies in agar showed that they grew as oblate spheroids rather than spheroids. In an average sample, 60-micron-diameter colonies contained eight to 10 cells; the range for the 38 samples was 1.2 to 48.5. These results precisely define colonies in terms of cell number. They allow calculation of the total number of cells formed from clonogenic cells, a more complete estimate of proliferation than conventional cloning efficiencies which only measure initial proliferation. Furthermore, because of the dependence on the size of the colony cells, if colonies are defined only by a specific diameter then they do not contain similar numbers of cells. Calculations which assume spherical colonies, rather than the oblate spheroid shape we found, greatly overestimate the number of cells within colonies. Our data can increase the accuracy of quantitation in the clonogenic system and thus improve the interpretation of the proliferation of clonogenic tumor cells.

Cell Count↗
PubMed1981

Single or multicellular origin of human T lymphocyte colonies in vitro: modification by 12-o-tetradecanoylphorbol 13-acetate (TPA).

The assumption that human T lymphocyte colonies have a unicellular origin has been directly tested with peripheral blood mononuclear cells from 2 women heterozygous for the common X-linked glucose-6-phosphate dehydrogenase (G-6-PD) gene (GdB) and the variant GdA. T cells were cultured in semisolid medium in the presence of phytohemagglutinin (PHA) and T lymphocyte growth factor with or without preincubation in suspension culture with PHA (2-stage and 1-stage assays, respectively). The enzyme type of individual T cell colonies was then determined electrophoretically at the lowest colony density with adequate growth (usually less than 100 colonies/dish). In the 2-stage system, 90 of 97 tested colonies had equal amounts of A and B enzyme activities suggesting multicellular origin of the colonies. Similarly, in the single-stage system, 21 of 31 colonies had both A and B enzymes. Increasing the density of the soft agar did not influence the frequency of A/B colonies. However, when 12-O-tetradecanoylphorbol 13-acetate (TPA), a promoter of T cell colony growth shown in other systems to inhibit metabolic cooperation, was added, a striking decrease in frequency of colonies with both G-6-PD types was found. In the 2-stage culture, 0 of 9 colonies had a double-enzyme type and in the single-stage system, the frequency of A/B colonies declined to 9 of 34 (p less than 0.025). The data suggest that despite the apparent multicellular origin of T cell colonies in cultures with TPA, most colonies do originate from single cells when cultured with TPA at low colony densities. Stimulation of cell growth or inhibition of metabolic cooperation between cells by TPA are possible explanations for these differences.

Cells, Cultured↗
PubMed1991

Effect of murine mast cell growth factor (c-kit proto-oncogene ligand) on colony formation by human marrow hematopoietic progenitor cells.

Purified natural (n) and recombinant (r) murine (mu) mast cell growth factor (MGF, a c-kit ligand) were evaluated alone and in combination with r human (hu) erythropoietin (Epo), rhu granulocyte-macrophage colony-stimulating factor (rhuGM-CSF), rhuG-CSF, and/or rhuM-CSF for effects in vitro on colony formation by multipotential (colony-forming unit-granulocyte, erythroid, monocyte, megakaryocyte [CFU-GEMM]), erythroid (burst-forming unit erythroid [BFU-E]) and granulocyte-macrophage (CFU-GM) progenitor cells from normal human bone marrow. MGF was a potent enhancing cytokine for Epo-dependent CFU-GEMM and BFU-E colony formation, stimulating more colonies and of a larger size than either rhu interleukin-3 (rhuIL-3) or rhuGM-CSF. MGF, especially at lower concentrations, also acted with rhuIL-3 or rhuGM-CSF to enhance Epo-dependent CFU-GEMM and BFU-E colony formation. MGF had little stimulating activity for CFU-GM colonies by itself, but in combination with suboptimal to optimal amounts of rhuGM-CSF enhanced the numbers and the size of CFU-GM colonies in an additive to greater than additive manner. While we did not detect an effect of MGF on CFU-G colony numbers stimulated by maximal concentrations of rhuG-CSF, MGF did enhance the size of CFU-G-derived colonies. MGF did not enhance the activity of rhuM-CSF. In a comparative assay, maximal concentrations of rmu and rhuMGF were equally effective in the enhancement of human bone marrow colony formation, but rhuMGF, in contrast to rmuMGF, did not at the concentrations tested enhance colony formation by mouse bone marrow cells. MGF effects on BFU-E, CFU-GM, and CFU-GEMM may be direct acting ones as MGF-enhanced colony formation by these cells in highly enriched progenitor cell populations of CD34 HLA-DR+ and CD34 HLA-DR+CD33- sorted cells in which greater than or equal to 1 of 2 cells was a BFU-E plus CFU-GM plus CFU-GEMM. MGF appears to be an early acting cytokine that preferentially stimulates the growth of immature hematopoietic progenitor cells.

Antigens, CD34↗
PubMed1988

Serum colony stimulating factors in patients undergoing bone marrow transplantation: enhancing effect of recombinant human GM-CSF.

Sera from 11 patients undergoing autologous or allogeneic BMT were tested for their content of megakaryocytic, granulocytic and erythrocytic colony stimulating factors. During the first week after BMT, all patients sera revealed a low/inadequate production of granulocytic, erythrocytic and megakaryocytic colony-stimulating activity (defined as the number of colonies per plate induced by 30% test serum from monocyte and T-lymphocyte depleted bone marrow cells). Thereafter an increase of colony-stimulating activity for all cell lineages tested was observed with peak levels between days 8 to 14 after BMT. The peak level was followed by a decline of colony stimulating activity, which shows an inverse correlation to basal blood leukocyte counts suggesting an adequate counter-regulation during this period. The GM colonies grown in the presence of patient serum were found to consist largely of neutrophilic granulocytes with only single monocytic colony, but without eosinophilic colony formation, suggesting that granulopoietic colony formation during this period is mediated predominantly by G-CSF and not by GM-CSF. All patients undergoing autologous BMT revealed a low/inadequate endogenous CSF production. rh GM-CSF addition in vitro was able to compensate from the impaired endogenous granulopoietic CSA in all patients and resulted in a constant augmentation of granulopoietic colony formation. The percentage of eosinophilic colony formation showed an inverse correlation to endogenous CSF production also suggesting that G-CSF is secreted during this period. In contrast to the granulopoietic colony formation, erythropoietic and megakaryopoietic colony formation was not enhanced by GM-CSF addition in vitro and even showed a slight reduction in some experiments. Our results suggest the treatment with recombinant GM-CSF might be beneficial for a faster reconstitution of granulo-monocytopoiesis after BMT, that rh GM-CSF therapy should be started immediately after bone marrow transplantation and that G-CSF is the main factor secreted in allogeneic bone marrow transplantations in the regeneration period.

Bone Marrow Transplantation↗
PubMed1987

Modest stimulatory effect of recombinant human GM-CSF on colony growth from peripheral blood human megakaryocyte progenitor cells.

Recombinant human granulocyte-macrophage colony-stimulating factor (rGM-CSF) has been previously demonstrated to stimulate colony formation from human myeloid, erythroid, and multipotential stem cells. In this investigation, we evaluated the effects of rGM-CSF on colony growth by human megakaryocyte progenitors (CFU-Meg). rGM-CSF was tested at concentrations of 0.1-100 U/ml in plasma clot cultures of adherent-depleted normal peripheral blood mononuclear cells. Control cultures were concurrently prepared containing either no stimulator or megakaryocyte colony-stimulating factor (Meg-CSF) partially purified from aplastic canine serum. rGM-CSF increased megakaryocyte colony numbers from a baseline of 4.3 +/- 1.4 (+/- SEM) in the unstimulated cultures to a maximum of 21.0 +/- 5.3 colonies at an rGM-CSF concentration of 1.0 U/ml. Corresponding megakaryocytic colony size increased from 4.4 to 8.3 cells/colony. Further increasing the rGM-CSF concentration resulted in decreasing megakaryocyte colony growth, reaching 6.8 +/- 2.9 colonies at 100 U/ml. The maximum number of megakaryocyte colonies stimulated by rGM-CSF was only 23.3% of that achieved in the control cultures containing optimal concentrations of serum-derived Meg-CSF protein (2.0 mg/ml). Megakaryocyte colonies stimulated by rGM-CSF consisted of predominantly low ploidy cells approximately equally distributed in 2N, 4N, and 8N ploidy classes. There was no increase in ploidy with any rGM-CSF concentration. These data indicate that rGM-CSF has modest activity in stimulating human megakaryocyte colony growth that is substantially less than that present in serum-derived Meg-CSF. rGM-CSF appears to primarily affect the early mitotic phase of megakaryocyte colony development with little influence on megakaryocyte endoreduplication.

Cell Division↗
PubMed1984

Augmentation of neutrophilic granulocyte progenitors in the bone marrow of mice with tumor-induced neutrophilia: cytochemical study of in vitro colonies.

Transplantation of CE mammary carcinoma into mice has been shown to produce marked neutrophilia. Previous studies in vivo indicated a significant increase in marrow neutrophil production in these mice, but regulatory mechanisms of this neutrophilia have not been well understood. In order to obtain information about neutrophil production mechanisms at the progenitor cell level, the profile of marrow granulocyte-macrophage progenitors in mice with neutrophilia induced by this tumor was quantitatively analyzed by cytochemical staining of in vitro colonies to distinguish colonies of neutrophils (N-colony), macrophages (M-colony), and mixed cells (NM-colony). Cell cycle kinetics of progenitors were studied by in vivo administration of cytocidal drugs. The absolute number of N-colonies in a femur increased significantly and reached three times normal three to four weeks after tumor implantation. The number of NM-colonies also increased significantly by the fourth week, but the number of M-colonies was unchanged. The number of N-colonies in a femur related directly to the degree of neutrophilia. The increased number of N-colonies from the marrow of tumor-bearing mice was not attributed to a different time course of colony growth nor to a different sensitivity to CSA; instead, a significantly larger fraction of neutrophilic progenitors from the tumor-bearing mice were in active cell cycle than were those of normal mice. The day 14 tumor-bearing mouse serum demonstrated N-colony stimulating activity while the sera of normal mice and day 7 tumor-bearing mice were inhibitory for in vitro colony growth. These studies demonstrated an increase in the numbers and turnover rate of marrow neutrophilic progenitors in CE tumor-induced neutrophilia, suggesting that this tumor stimulates proliferation of these progenitors in vivo.

Animals↗
PubMed1991

Immunobiology of hematopoietic colony-stimulating factors: potential application to disease prevention in the bovine.

Colony-stimulating factors are a family of glycoproteins instrumental in regulation of hematopoiesis and inflammation. Clinical effects of various colony-stimulating factors have been reported in murine and human hosts. This review summarizes findings from some clinical trial evaluations of macrophage colony-stimulating factor, granulocyte-macrophage colony-stimulating factor, granulocyte colony-stimulating factor, interleukin-1, interleukin-3, interleukin-4, interleukin-5, interleukin-6, and interleukin-7 administration to other species. These factors stimulate clonal expansion of progenitor cells in the bone marrow, induce differentiation of various cell lineages to a mature phenotype, and, in some cases, enhance the effector activities of immune cells. Each colony-stimulating factor has distinct lineages of bone marrow cells upon which they act, although there is some overlap in lineage activity and synergy between colony-stimulating factors. The close relationship in biological activity among different colony-stimulating factors is also reflected at the genomic level at which genes for some hematopoietic growth factors have been mapped to a region of human chromosome 5. Recently, colony-stimulating factor administration to cattle and its potential application to disease control in bovine preventive medicine programs has been investigated. Data from recent hematological, immunological, and intramammary bacterial (Staphylococcus aureus and Klebsiella pneumoniae) challenge studies in dairy cows are reviewed. These studies, with limited numbers of cows, found that rate of new infections, as well as duration and severity of infection, were reduced by pretreatment of cows with granulocyte-colony stimulating factor. The dose-dependent hematological and immunomodulatory effects of granulocyte colony-stimulating factor administration may explain reduced severity and incidence of mastitis in dairy cows given granulocyte colony-stimulating factor.

Animals↗
PubMed1991

Characterization of spleen colonies derived from mice with mutations at the W locus.

Mice with mutations at the W locus have a hemopoietic stem cell defect characterized by an apparent deficiency of spleen colony forming cells (CFU-S). In the present report, we provide evidence that mutant cells form colonies and we compare the characteristics of the colonies derived from mutant and normal cells. To perform the colony-derivation studies, marrow cells were transferred into lethally irradiated congenic hosts that differed from the donors in the ubiquitous genetic marker, glucose phosphate isomerase (GPI-1). Donor GPI-1 comprised over 50% of the marker in the host spleen and marrow by 12 days post injection, regardless of whether the donor was mutant or normal. To characterize the colonies, serially sectioned host spleens were examined microscopically. Colonies are present by 8 days post-transplantation regardless of donor genotype, but mutant colonies are distinctly different from normal colonies. The proportion of blast and granulocyte colonies is always greater in W/Wv than in +/+ recipients. Unlike the W/Wv donors, the +/+ donors generate primarily erythrocyte colonies at 8, 10, and 14 days and mixed colonies at 12 days post-injection. Colonies from the mutant mice are generally smaller but visible colonies do appear by 12 days. The results are consistent with the notion that the anemia in W/Wv mice is caused by the early restriction of differentiating cells to a non-erythrocyte lineage accompanied by the delayed amplification of mutant hemopoietic cells. Whether this means erythrocyte-committed cells are absent or are present but unable to respond to the appropriate cytokines is not possible to determine from the current experiments.

Animals↗