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G Wagemaker

Publications and source records attributed to G Wagemaker.

At least 37 records · Page 2Linked to original sources
PubMed1987

Characterization of a human multilineage-colony-stimulating factor cDNA clone identified by a conserved noncoding sequence in mouse interleukin-3.

Blood-cell production is regulated by hemopoietic growth factors, which act at specific stages of hemopoietic cell differentiation. Murine interleukin-3 (mIL-3)/multilineage colony-stimulating factor (multi-CSF) has been shown to stimulate colony formation in vitro by multipotent hemopoietic cells and production of spleen colony-forming units (CFU-S) in suspension cultures. The molecular cloning of the human counterpart of mIL-3 is described here. Hybridization of radiolabeled mIL-3 cDNA with a cDNA library obtained from mRNA of stimulated human lymphocytes resulted in the identification of a human (h)multi-CSF cDNA clone. Sequence homology (73%) in the 3'-noncoding region of mIL-3 enabled the detection of the hmulti-CSF cDNA clone. Whereas only 45% sequence homology was found in the coding region, specific A + T-rich domains in the 3'-noncoding region were highly conserved (93%). As far as we know, this is the first example of gene identification by sequence homology occurring only within the 3'-noncoding region. The protein encoded by this hmulti-CSF cDNA stimulates in vitro colony formation by multipotent human hemopoietic stem cells. In addition, the growth factor strongly stimulates the in vitro proliferation of human leukemic blast cells.

Animals↗
PubMed1987

Correction of lysosomal enzyme deficiency in various organs of beta-glucuronidase-deficient mice by allogeneic bone marrow transplantation.

The correction of lysosomal enzyme deficiency was investigated for various organs of beta-glucuronidase-deficient C3H/Rij mice after allogeneic bone marrow transplantation from an enzymatically normal donor strain (C57BL/Rij). In the hemopoietic organs, the enzyme level increased to levels found in donor mice. In lung, kidney, liver, and peripheral nervous tissue, a significant increase in enzyme activity was seen to levels intermediate between those of donor and recipient. Increased enzyme activity was maintained throughout the observation period of 150 days. In skeletal muscle tissue, enzyme levels tended to be higher in recipient mice, but this increase was not significant for all data points. Bone marrow transplantation failed to significantly affect enzyme activity in central nervous system tissue. These data suggest that beneficial effects expected from bone marrow transplantation for lysosomal enzyme deficiencies depend on the type of tissue involved in the disease. In diseases severely affecting the central nervous system, cure may not be expected from bone marrow transplantation alone, whereas in diseases with only minimal central nervous system involvement, alleviation or prevention of clinical symptoms may occur.

Animals↗
PubMed1987

Human recombinant multilineage colony stimulating factor (interleukin-3): stimulator of acute myelocytic leukemia progenitor cells in vitro.

Acute myeloid leukemia colony forming cells (AML-CFU) require the addition of colony stimulating factors (CSFs) for in vitro proliferation. Recently, we isolated a human recombinant multilineage CSF (hMulti-CSF). We investigated the ability of hMulti-CSF to stimulate AML clonogenic cells in seven patients in direct comparison with the effects of human granulocyte CSF (hG-CSF), human granulocyte-macrophage CSF (hGM-CSF), and feeder leukocytes. We show that hMulti-CSF is an efficient stimulator of AML colony formation in four of seven cases. In these patients, hGM-CSF was also capable of stimulating AML colonies in vitro. In two of seven cases hMulti-CSF appeared to be a weak stimulus of AML-CFU proliferation. In these latter two cases, however, hG-CSF and in one case hGM-CSF effectively stimulated AML-CFU growth. In one patient none of the hCSFs, either alone or in combination, induced AML colony formation, whereas AML colonies consistently appeared in the phytohemagglutinin (PHA) leukocyte feeder assay. This finding suggests that PHA stimulated leukocytes produce components other than the tested hCSFs that may have a role in the proliferation of AML cells in vitro. Multi-CSF, like hGM-CSF, revealed a limited capacity to induce progressive maturation during AML colony growth, ie, not beyond the promyelocytic stage. On the other hand, in one case, hG-CSF stimulated the growth of AML colonies containing (meta)myelocytes and granulocytes. We conclude that hMulti-CSF is a regulator of AML-CFU proliferation in a significant number of cases. The patterns of responsiveness of AML precursors to the three hCSFs in different patients show a striking variability, which may indicate that AML-CFU are the neoplastic representatives of normal bone marrow progenitors at different stages of maturation and with distinct CSF requirements.

Adult↗
PubMed1986

Bone-marrow transplantation for immunodeficiencies and osteopetrosis: European survey, 1968-1985.

In this retrospective analysis of allogeneic bone-marrow transplantation (BMT) carried out between 1969 and 1985 at fourteen European centres in 162 patients with sixteen different types of inherited immunodeficiencies and osteopetrosis, the overall survival with functional grafts was 51.7% (85 patients), with a minimum follow-up of 5 months. In patients with severe combined immunodeficiency HLA-matched (n = 41) and T-cell-depleted HLA-mismatched BMT (n = 46) resulted in 68% and 57% disease-free survival, respectively; after HLA-mismatched transplants, older age (greater than 6 months) and adenosine-deaminase deficiency resulted in poorer survival. Eight other lethal immunodeficiencies, including profound T-cell deficiencies, Wiskott-Aldrich syndrome, Kostmann syndrome, LFA-1/CR 3/p150,95 deficiency, and Chediak-Higashi syndrome as well as malignant osteopetrosis, have been successfully treated by BMT. In this group, survival with functional graft was 47% with HLA-matched and 29% with T-cell-depleted HLA-mismatched BMT. Engraftment failure was the major complication in this group. Poorer prognosis was associated with older patients, profound T-cell deficiencies, and the degree of HLA incompatibility.

Adolescent↗
PubMed1986

A fractionation procedure of mouse bone marrow cells yielding exclusively pluripotent stem cells and committed progenitors.

The cell surface phenotype of pluripotent hemopoietic stem cells (CFU-S) and committed progenitors (CFU-C1, CFU-C2, BFU-E) of mouse bone marrow was analyzed with respect to their binding of wheat germ agglutinin (WGA) and two monoclonal antibodies, anti-GM-1.2 and anti-PGP-1. Stained cells were fractionated on the basis of differences in fluorescence and light scatter intensity using a light-activated cell sorter. The 6% of the cells that bound most WGA and that also had a relatively high forward light scatter (FLS) and low perpendicular light scatter (PLS) contained nearly all stem cells (CFU-S) and progenitors. Anti-GM-1.2 stained only mature myeloid cells, not CFU-S or the in vitro colony-forming cells. Anti-PGP-1 stained all bone marrow cells in varying intensities: lymphoid cells were dull, CFU-S were intermediate, CFU-C2 were brighter, and mature myeloid cells very bright. Enrichment of progenitor cells was performed by a two-step sorting procedure. First, the 6% most WGA-binding cells with high FLS and low PLS were sorted out. A 10-15-fold enrichment of progenitors and CFU-S was obtained. Next, these cells were restained with anti-GM-1.2 or anti-PGP-1 and again fractionated on the FACS. The GM-1.2-negative cells were then another four- to sevenfold more enriched for stem cells and progenitors. Of the cells in this fraction, 95% could be assigned to a colony-forming unit. With anti-PGP-1, CFU-C2 could be partly separated from more early cells such as CFU-S and BFU-E.

Animals↗
PubMed1986

Cure of murine thalassemia by bone marrow transplantation without eradication of endogenous stem cells.

alpha-Thalassemic heterozygous (Hbath/+) mice were used to investigate the possible selective advantage of transplanted normal (+/+) hemopoietic cells. Without conditioning by total-body irradiation (TBI), infusion of large numbers of normal bone marrow cells failed to correct the thalassemic peripheral blood phenotype. Since the recipients' stem cells are normal with respect to number and differentiation capacity, it was thought that the transplanted stem cells were not able to lodge, or that they were not stimulated to proliferate. Therefore, a nonlethal dose of TBI was given to temporarily reduce endogenous stem cell numbers and hemopoiesis. TBI doses of 2 or 3 Gy followed by infusion of normal bone marrow cells proved to be effective in replacing the thalassemic red cells by normal red cells, whereas a dose of 1 Gy was ineffective. It is concluded that cure of thalassemia by bone marrow transplantation does not necessarily require eradication of thalassemic stem cells. Consequently, the objectives of conditioning regimens for bone marrow transplantation of thalassemic patients (and possibly other nonmalignant hemopoietic disorders) should be reconsidered.

Animals↗
PubMed1986

Graft-versus-host disease following transplantation of 'one log' versus 'two log' T-lymphocyte-depleted bone marrow from HLA-identical donors.

Prevention of acute graft-versus-host disease (GVHD) after allogeneic bone marrow transplantation, requires the depletion of mature T-lymphocytes from bone marrow grafts. The optimal degree of T-cell reduction is still an open question. We compared two procedures of T-cell separation in 18 consecutive recipients of genotypically HLA-matched bone marrow, who also received cyclosporin A for 6 months. The first method (A) was based on a discontinuous albumin gradient fractionation and resulted in an average T-lymphocyte content of 50 X 10(5)/kg body weight (n = 9 patients); the second method (B) was based on E-rosette sedimentation and reduced the contamination to 15 X 10(4) grafted T-lymphocytes/kg body weight on the average (n = 9 patients). Thus, approximately 90 and 99% of the original T-lymphocytes were removed from the marrow grafts respectively. Of the seven patients of the first group who were at risk of GVHD (excluding two cases of early death), five developed a minimal-to-moderately severe acute GVHD and in two cases chronic GVHD ensued. Lethal GVHD was not seen. Of group B, all recipients engrafted and none developed GVHD (0/9). The difference in the frequency of GVHD between the two groups was highly significant (P less than 0.0025). These data confirm our preclinical studies. They demonstrate that a one-log T-lymphocyte reduction of the marrow inoculum, when combined with cyclosporin A prophylaxis after major histocompatibility complex (MHC)-matched transplantation, is still associated with a considerable incidence of GVHD, whereas a two-log reduction of T-lymphocytes may provide full protection against acute GVHD.

Adolescent↗
PubMed1986

Enumeration of stem cells and progenitor cells in alpha-thalassemic mice reveals lack of specific regulation of stem cell differentiation.

Heterozygous alpha-thalassemic (Hbath/+) female mice were investigated for the effect of persistent erythropoietic stress on the number of stem cells and progenitor cells along the the erythroid (E), granulocyte-macrophage (GM), and megakaryocyte (Meg) pathways. At the progenitor cell level, compensatory erythropoiesis was demonstrated in the spleen but not in the bone marrow. In the spleen, developmentally early progenitor cells (BFU-E) were expanded two- to threefold and late progenitor cells (CFU-E) five- to sixfold. A comparable expansion of progenitor cells was observed along the GM and Meg pathways. CFU-S numbers were increased in the spleen, but not in the bone marrow. The increases in GM and Meg progenitor cells appeared to result in an inappropriate hemopoiesis: peripheral thrombocyte and monocyte numbers were elevated. However, granulocyte numbers were not significantly increased. It is concluded that the persistently increased erythropoietic demand results in inappropriate production of other hemopoietic cells, most likely because pathway-specific regulatory mechanisms do not influence differentiation at the stem cell level.

Animals↗
PubMed1985

Failure to demonstrate pluripotential hemopoietic stem cells in mouse brains.

Hemopoietic stem cells as defined by the capacity to produce spleen colonies in lethally irradiated recipients were reported by P. F. Bartlett [(1982) Proc. Natl. Acad. Sci. USA 79, 2722-2725] to be present in high frequencies in mouse brain. He also reported similar numbers of colony-forming units, spleen (CFU-s), in the brains of Wf/Wf mice, the bone marrow of which lacks detectable spleen colony-forming cells. To verify these observations, single cell suspensions were produced from murine brains by incubation with trypsin and DNase, followed by removal of myelin by Percoll gradient centrifugation. Two to 13 CFU-s were detected per brain. This low number suggested contamination of the brains by either blood or bone marrow leaking from the skull bones during dissection. When the isolated, intact brains were washed carefully in balanced salt solution, the recovered number of CFU-s decreased to 0.1-0.4 per brain. No CFU-s could be detected in the brains of W/Wv mice. It is concluded that the CFU-s observed by Bartlett in preparations of mouse brain did not originate from the brain tissue.

Animals↗
PubMed1985

Biochemical fractionation of conditioned media containing factors which support in vitro proliferation of high proliferation potential colony forming cells.

Synergistic activity (SA), which is the capacity to support the in vitro proliferation of High Proliferation Potential Colony Forming Cells (HPP-CFC's), has been fractionated from conditioned media by standard biochemical techniques. On fractionation of both Wehi conditioned medium (Wehi CM) or human placental conditioned medium (HPCM) by several techniques, multiple peaks of SA were observed. Protein from HPCM expressing SA, ranged from 9,000-28,000 in molecular weight as determined by gel filtration. Chromatofocusing crude HPCM separated two activities possessing isoelectric points of 5.7 and 5.3. In crude Wehi CM, inhibitors or toxicity occasionally masked SA which partially adsorbed to Con-A sepharose and could be eluted with competing sugar. Further fractionation of this material on DEAE-sepharose separated three peaks of activity. Pooling the active fractions from the first two peaks gave a preparation that was up to 179 fold more active than the crude material.

Animals↗
PubMed1985

Reconstitution of the W/Wv stem cell differentiation defect by infection with Rauscher leukemia virus.

Hematopoietic stem cells of W/Wv mice failed to produce macroscopically visible hematopoietic spleen colonies in irradiated recipient mice. Infection of W/Wv mice of the spleen focus-forming virus-susceptible genotype Fv-2ss (DBA/2) or Fv-2rs (BD2F1) with Rauscher leukemia virus (RLV) restored the spleen colony-forming capacity of the stem cells. The resulting spleen colonies had normal size and cellularity; the frequency of and ratio between granulocyte-macrophage and erythroid progenitor cells were also normal, without excessive production of erythroid cells. The frequency of spleen colony-forming units (CFU-S) appeared to be strongly reduced in W/Wv mice. The seeding fraction of RLV-infected W/Wv stem cells in the recipient spleens did not differ from that of uninfected or RLV-infected +/+ stem cells. At equivalent numbers of CFU-S, spleen suspensions of RLV-infected W/Wv mice were equally effective as +/+ control suspensions in protecting irradiated mice from death due to bone marrow failure. Thus the number of CFU-S observed appeared to be predictive for the number of W/Wv cells required for effective radioprotection. In irradiated W/Wv mice that received transplants of RLV-infected W/Wv cells, circulating erythrocyte numbers approached those of control mice; the erythrocytes were of normal size, in contrast to the macrocytic red cells of untreated W/Wv mice. The reduced frequency of CFU-S in RLV-infected W/Wv mice can be readily explained by a reduced self-replicating capacity, attributable to the W/Wv genes, which was not reconstituted by infection with RLV. The data indicate a direct involvement of pluripotent stem cells upon infection with RLV.

Anemia, Macrocytic↗
PubMed1979

Structural identity of the pluripotential hemopoietic stem cell.

A review is presented of the experiments that resulted in the identification of a specific morphologic entity representing the pluripotential hemopoietic stem cell (HSC) in mouse bone marrow. This entity was subsequently discovered in concentrated HSC preparations from bone marrow of rats, monkeys, and humans. In the mouse, a set of physical parameters (of the HSC) has been collected which agree with its morphologic description. It was also shown that these physical properties, and a number of cell surface properties, do not enable a distinction between HSC and its immediate descendants, the G/M CFU 1 and the E-BFU. The factors that stimulate proliferation of these three cell types have been isolated from human leukocyte conditioned medium and mouse spleen conditioned medium and were partly purified and characterized. The information at present indicates that the three cell types respond to closely related, if not identical, factors. Direct counts of HSC in electron microscopic preparations of density gradient fractions of different enrichment have been compared with HSC values computed from spleen colony counts and f factors for rat and mouse marrow. A high degree of correlation was found between the two types of observations. The slopes of the regression lines for mouse marrow fractions, for concentrates of normal rat marrow, and for concentrates of cycling rat marrow were the same, namely, 0.5. The deviation of this value from the expected value of 1.0 is probably not due to the use of erroneous f values. It is proposed that the observed discrepancy may be due to heterogeneity of spleen colony forming cells, in that a proportion of them may not be pluripotential.

Animals↗
PubMed1979

Induction of erythropoietin responsiveness in vitro by a distinct population of bone marrow cells.

Bone marrow contains a small population of primitive erythroid progenitor cells which can be detected by their capacity to form large numbers of erythroid progeny in viscous cultures containing erythropoietin (EP). These cells have been termed erythroid 'burst-forming units' (BFUe). The present study demonstrates that expression of the erythroid differentiation potential of BFUe requires the presence of an activity additional to EP. This activity has been designated as BFA (burst feeder activity). It is shown that the number of BFUe detected and their apparent sensitivity to EP are directly related to the BFA concentration of the cultures. BFA was found to be associated with a population of bone marrow cells of high buoyant density and small volume, which are sensitive to irradiation. The radiation dose-effect curve provided strong evidence that bone marrow BFA is independent of cell proliferation; this was supported by showing that BFA is unaffected by in vivo treatment with hydroxyurea. The findings are compatible with a two-step regulation model for erythroid differentiation in which BFA-induced progeny of BFUe acquire sensitivity to EP.

Animals↗
PubMed1979

Particle-induced erythropoietin-independent effects of erythroid precursor cells in murine bone marrow.

A possible regulatory action of phagocytic cells on erythropoiesis was investigated by infusion of inert polystyrene latex particles (LAT). LAT appeared to induce changes in the femoral content of erythroid progenitor cells. These changes were most pronounced in primitive erythroid progenitor cells (BFUe) and appeared to be gradually damped in more differentiated populations (CFUe and erythroblasts). LAT did not influence granulocyte/macrophage progenitor cells (CFUc). The effects of LAT could not be attributed to changes in the systemic erythropoietin (EP) concentration. Administration of dexamethason nullified the effect of low doses of LAT, suggesting that phagocytosis of the particles is essential to the observed effects. Erythroid burst formation was previously found to be dependent on a bone marrow associated activity, termed BFA (burst feeder activity). BFA acts as an in vitro inducer of EP-responsiveness in BFUe. In this study it was found that LAT-induced changes in femoral erythroid progenitor cell content were characteristically preceded by corresponding changes in BFA. It was concluded that BFA-associated cells probably play a role in vivo in the early differentiation of erythroid progenitor cells. The present data are interpreted as direct in vivo evidence supporting a two-step regulatory model operating in erythropoiesis and provide evidence that phagocytic cells are a component of the erythroid haemopoietic inductive micro-environment.

Animals↗