摘要:

AbstractThe present study was undertaken to elucidate the role of T cell subsets in regulating the in vitro growth of human granulopoietic progenitor cells (CFU‐C). Prior to CFU‐C assay, mononuclear cells obtained from bone marrow and cord blood were depleted of T cells or functionally distinct T cell subsets by the method of complement‐mediated cytolysis with the use of monoclonal antibodies, OKT3, OKT4 and OKT8. The depletion of any T cell subset of OKT3+, OKT4+or OKT8+cells from bone marrow and cord blood cells showed no significant alterations in the generation of CFU‐C. The supplementation to the in vitro culture system of OKT4+or OKT8+cells, which had been negatively selected by complement‐mediated cytolysis using the mutually exclusive monoclonal OKT8 or OKT4 antibody, respectively, did not alter the growth of CFU‐C‐derived colonies without mitogenic stimulation. In contrast, the production of colony‐stimulating activity (CSA) in peripheral blood mononuclear cells was significantly reduced by removing not only OKT3+cells but also OKT4+or OKT8+cell subsets. There were no significant differences in the degree of reduction between the different procedures. These results suggested that T cell subsets played an important role in the regulation of steady‐state granulopoiesis through the stimulation of CSA production. The presence of a specific subset of T cells in CSA production was

ISSN:0737-1454    

DOI:10.1002/stem.5530010301

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY

摘要:

AbstractVindesine (VDS) is a new vinca‐alkaloid related to vinblastine and vincristine that blocks production of the microtubules in the mitotic phase of the cell cycle. Studies were undertaken to investigate the inhibitory effect of VDS on normal murine bone marrow cell proliferation and the possible interactions between this compound and L‐cell derived colony stimulating factor (CSF). One × 107 murine bone marrow cells were exposed to various concentrations of VDS, ranging from 0.1 to 1.5 μg/ml for 1 h at 37°C. Following this period, the cells were plated in agar in the presence of 100 units of CSF. A dose‐dependent inhibition of colony formation was noted with increasing doses of the drugs. To determine whether an increased dose of CSF could overcome the inhibitory effect of VDS, further studies compared colony growth in response to 100 and 200 units of CSF. Virtually no inhibition of colony growth was detected in VDS‐treated cells exposed to this higher dose of CSF while a dose‐dependent reduction in CFU‐C was noted with 100 units of CSF. Preincubation of cells with VDS and CSF prevented the inhibition that occurred with VDS alone. The addition of anti‐CSF serum during the preincubation phase abolished the protective effect of CSF. The studies show that short‐term exposure of marrow cells to VDS causes a dosedependent inhibition of in vitro colony formation; this inhibition is prevented by increasing doses of CSF in agar culture or by simultaneous preincubation with CSF. The CSF action appears specific as its protective effect is neutralized by antibody to CSF, suggesting a potential role for CSF in preventing the antimitot

ISSN:0737-1454    

DOI:10.1002/stem.5530010302

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY

摘要:

AbstractThe definition of the function of bone marrow strornal cells in the regulation of hematopoiesis has been complicated by the limited growth of these cells in vitro. We have demonstrated that the addition of 2‐mercaptoethanol to rat bone marrow cultures enhances bone marrow fibroblast proliferation as evidenced by a 2‐fold increase in the total number of fibroblast colonies and a 5‐fold increase in the number of these colonies which contain more than 80 cells. We also present evidence suggesting that enhancement of fibroblast growth may not be due to direct action of 2‐mercaptoethanol, but may result from the activation of a serum component. The results from this study should facilitate further research into the function of bone marrow fibroblasts in the regulation of hema‐topoietic cell differ

ISSN:0737-1454    

DOI:10.1002/stem.5530010303

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY

摘要:

AbstractRecent progress in clonal cell culture techniques makes it possible to detect pluripotent hemopoietic precursors from murine marrow cells. The precursors can proliferate, differentiate and form mixed colonies containing eryth‐roblasts, granulocytes, macrophages and often megakaryocytes in viscid culture medium. In the present investigation, the presence of cells of B‐cell lineage in mixed colonies was investigated.Experiments on colonies containing clgM, clgG, slgM and slgG bearing cells using goat IgG fluorescein‐conjugated anti‐mouse IgM, goat F(ab′)2fraction fluo‐rescein‐conjugated anti‐mouse IgG and immunobeads revealed the presence of cytoplasmic IgM bearing cells in 47% of the colonies and surface IgM bearing cells in 74‐84% of the colonies. Mixed colonies, however, did not contain either clgG bearing cells or slgG bearing cells. The results may indicate that some CFU‐MIX proliferate and differentiate along B‐cell lineage to slgM or clgM b

ISSN:0737-1454    

DOI:10.1002/stem.5530010304

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY

摘要:

AbstractA transient increase in terminal deoxynucleotidyl transferase positive (TdT+) cells was observed during the early phase of (≤ day 5) cultures supporting the growth of pluripotent myeloid progenitor cells (CFU‐mix). T‐cell growth‐promoting medium and erythropoietin were not required. The rapidity with which TdT+cells appeared in cultures and the results of cultures where TdT+cells were high initially (>800 cells/culture) were not consistent with their having been produced by proliferation of pre‐existing TdT+cells from the bone marrow inoculum.The results suggest production of TdT+cells from a TdT‐negative precursor either by altered enzyme expression or by production of

ISSN:0737-1454    

DOI:10.1002/stem.5530010305

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY

ISSN:0737-1454    

DOI:10.1002/stem.5530010306

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1983

数据来源: WILEY