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M Y Gordon

Publications and source records attributed to M Y Gordon.

152 records · Page 9Linked to original sources
PubMed1975

Quantitative measurements on the haemopoietic systems of three strains of mice.

Quantitative measurements on the haemopoiedic systems of SAS/4, 3H and RFM mice have been used to calculate the distribution and population sizes of haemopoietic cells in the bone marrow, spleen and peripheral blood. Considerable strain differences have been found in the sizes of haemopioetic stem cell populations and in the distribution of these cells within the haemopioetic system, although the incidence of CFU-S was shown to be uniform throughout skeletal sites of haemopioesis. The seeding efficiency of colony forming cells in the spleen, measured by the 'f" factor 24 hours after irradiation and transplantation, also differs between strains and between the bone marrow and spleen of the strains investigated.

Animals↗
PubMed1974

Quantitation of haemopoietic cells from normal and leukaemic RFM mice using an in vivo colony assay.

The conventional diffusion chamber (CDC) as described by Benestad (1970) had been modified to assay the colony forming capacity of RFM bone marrow and spleen cells in agar diffusion chambers (ADCs). The colonies are morphologically identical to those formed by the CFUc in agar culture in vitro and have an incidence of approximately 1 in 10(3) normal nucleated bone marrow cells, and 1 in 10(4) nucleated spleen cells. Comparison of the growth of normal bone marrow cells in CDCs and in ADCs suggests that cell proliferation in diffusion chambers may result from the same precursor cell as detected by colony formation in agar culture in vitro. This proposal is supported by the suicide of approximately 46% of the ADC colony precursor cells following incubation with (3)H-labelled thymidine.Colony formation by haemopoietic cells taken from leukaemic mice appears to be due to the proliferation of a remaining normal cell population alone, while the leukaemic cells in the inoculum form a background of uniformly distributed blast cells. In the case of leukaemic cell culture, there are differences in the results from CDCs and ADCs, and data from colonies in leukaemic ADC cultures are similar to those from normal ADC colonies. These comparisons imply that the ADC technique may be used to monitor the functional capacity of normal bone marrow, by its ability to form colonies, during the development of leukaemia. A humoral effect of a leukaemic environment on the growth of normal bone marrow cells in ADCs has also been detected.

Age Factors↗
PubMedDate not supplied

Compartmentalization of a haematopoietic growth factor (GM-CSF) by glycosaminoglycans in the bone marrow microenvironment.

Haematopoietic progenitor cells proliferate and mature in semisolid media when stimulated by exogenous haematopoietic cell growth factors (HCGFs) such as granulocyte-macrophage colony-stimulating factor (GM-CSF). They also proliferate in association with marrow-derived stromal cells although biologically active amounts of HCGFs cannot be detected in stromal culture supernatants. It is possible that HCGFs are synthesized in small amounts by stromal cells but remain bound to the stromal cells and/or their extracellular matrix (ECM). This interpretation accords with haematopoietic progenitor cell proliferation in close association with stromal layers in long-term cultures. Glycosaminoglycans (GAGs) are found in the ECM produced by stromal cells. They are prime candidates for selectively retaining HCGFs in the stromal layer; they influence embryonic morphogenesis and cyto-differentiation and they may regulate haematopoiesis. We now report that granulocyte-macrophage colony-stimulating activity can be eluted from cultured stromal layers and that exogenous GM-CSF binds to GAGs from bone marrow stromal ECM. Selective compartmentalization of HCGFs in this manner may be an important function of the marrow microenvironment and may be involved in haematopoietic cell regulation.

Animals↗
PubMedDate not supplied

Altered adhesive interactions with marrow stroma of haematopoietic progenitor cells in chronic myeloid leukaemia.

Normal haematopoietic cell regulation involves interaction between marrow stromal cells and haematopoietic progenitor cells which may be facilitated by specific recognition and adhesion. Some leukaemogenic events might produce a selective growth advantage by altering this regulatory network, possibly by diminishing the capacities of cells to adhere to stromal elements. Using an in vitro culture system which allows investigation of adhesion to stromal layers and subsequent colony formation by blast colony-forming cells (B1-CFC) in normal marrow and Ph+ chronic myeloid leukaemic (CML) blood, we compared the adhesive properties of normal and malignant progenitor cells. We present evidence that altered adhesive interactions between primitive progenitor cells and marrow stromal cells occur in CML.

Bone Marrow↗
PubMedDate not supplied

Sources of human hematopoietic stem cells for transplantation--a review.

Transplantation of hematopoietic stem cells provides a means of replacing a defective hematopoietic system in patients with a wide range of malignant and nonmalignant disorders that affect the blood forming tissue. The same procedure has also allowed dose-escalation of standard chemotherapy and radiotherapy in the treatment of malignant disease of nonhematological origin. Unit recently, bone marrow has been the sole source of hematopoietic stem cells, but limitations of conventional bone marrow transplantation have stimulated a search for alternative sources and uses of stem cells. Fetal tissues (especially liver) are a recognized source of transplantable stem cells and offer the great advantage of reduced immunogenicity, potentially removing the problems of tissue type matching. Umbilical cord blood is also a rich source of stem cells and, although it contains alloreactive cells, it is readily available without special ethical constraints. Both fetal tissue and cord blood suffer the disadvantages of limited numbers of stem cells per donation, and there is much interest in the development of technologies for the safe and reliable expansion and/or pooling of stem and progenitor cells. The observation that small numbers of stem cells are found in the peripheral blood of adults has led to the exploitation of the blood as a further source of stem cells. The ability to mobilize these cells from the medullary compartment into the periphery by the use of chemotherapy and/or recombinant hematopoietic growth factors has enabled the collection of sufficient numbers of cells for transplantation purposes. All of these advances are increasing the options and the range of choices available to clinicians and patients in the arena of hematopoietic stem cell transplantation.

Bone Marrow Cells↗
PubMedDate not supplied

Reconstruction of the hematopoietic system after stem cell transplantation.

The practice of hematopoietic stem cell transplantation to rescue patients from the myeloablative effects of chemo- or radiotherapy, or to replace defective hematopoiesis, is based on the assumption that hematopoietic stem cells in the graft have sufficient proliferative potential to supply mature blood cells for the remainder of the recipient's lifespan. However, the mechanism(s) whereby this is achieved are not well understood. Here we address the reconstruction of the hematopoietic system by considering the effects of stem cell and progenitor cell renewal and differentiation. We conclude that stem cell self-renewal is necessary for hematological recovery and that infused committed progenitor cells (CFU-GM) may contribute to the neutrophil count in the early posttransplant period.

Animals↗