摘要:

AbstractMyelodysplastic syndromes (MDS) represent a diverse spectrum of disorders ranging from refractory anemia to a preleukemic state. Peripheral cytopenias, cellular marrow, dyplasias and dysfunctions of myeloid and lymphoid cells constitute hematological hallmarks, and are caused by ineffective hemopoiesis. Investigations of cell cultures and cellular functions indicate that the disease originates in a stem cell pluripotent to all myeloid cells and possibly lymphoid cells as well. The disease commonly runs a chronic indolent course, often terminating in acute leukemia or nonleukemic death, notably infections and/or hemorrhage due to cytopenias and cellular dysfunctions. Clonal expansion or clonal evolution appears to be related to the disease progression with a greater degree of malignancy. However, the initial sequence of events causing damage to stem cells is still undefined.

ISSN:0737-1454    

DOI:10.1002/stem.5530050502

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

年代:1987

数据来源: WILEY

摘要:

AbstractA semisolid culture system for B‐cell colony formation is described. The system includes pretreatment of B‐cells by neuraminidase‐galactose oxidase and help of mitomycin‐treated T‐cells. With this assay system, colony‐forming B‐cell precursors were detected in all eight patients we studied with B‐cell chronic lymphocytic leukemia. These patients' own T‐cell helper effect was less than that

ISSN:0737-1454    

DOI:10.1002/stem.5530050503

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

年代:1987

数据来源: WILEY

摘要:

AbstractA simplified methodology has been developed which makes it possible to examine the ultrastructural details of cells cloned in vitro while retaining the cell/cell relationships within semi‐solid cultures. Using mouse erythropoiesis as the model for study, electron microscopy revealed many normal characteristics of red blood cell differentiation and maturation, as well as several distinct dyserythropoietic features. The usefulness of this technology should apply to fine structural studies of clonally‐derived material such as hematopoietic cells, tumor cell lines and primary tumor cultu

ISSN:0737-1454    

DOI:10.1002/stem.5530050504

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

年代:1987

数据来源: WILEY

摘要:

AbstractWe investigated the effect of a recombinant human erythropoietin preparation (recombinant Epo) on murine megakaryocyte (MK) colony formation in serum‐free and serum‐containing culture systems, in order to study the relationship between Epo and megakaryopoiesis. Pokeweed mitogen spleen‐conditioned medium (PWM‐SCM), a standard source of MK colony stimulator, dose‐dependently stimulated MK colony formation in the two culture systems. The plating efficiency of serum‐free cultures was almost equal to that of cultures containing serum.Recombinant Epo also dose dependently stimulated MK colony formation in serum‐containing cultures. However, in serum‐free cultures recombinant Epo alone did not stimulate the growth of MK colonies; with the addition of fetal calf serum (FCS) to the serum‐free cultures, recombinant Epo induced the growth of MK colonies. Furthermore, recombinant Epo enhanced MK colony formation through the stimulation of PWM‐SCM or murine interleukin 3 (IL‐3) in serum‐free cultures. Our data show that Epo can act as a stimulator of megakaryopoiesis in collaboration with a factor in serum, or with an MK colony

ISSN:0737-1454    

DOI:10.1002/stem.5530050505

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

年代:1987

数据来源: WILEY

摘要:

AbstractThe effect of low oxygen tension on the growth of human hemopoietic progenitor cells in bone marrow was investigated using the semisolid methylcellulose colony assay. The clonal growth of granulocyte‐macrophage progenitors (CFU‐gm), early (BFU‐e) and late (CFU‐e) erythroid progenitors, megakaryocyte progenitors (CFU‐meg) and pluripotent progenitors (CFU‐mix) improved more markedly in incubation at the low oxygen tension (5%) than in conventional air (20%). The thiol compound 2‐mercaptoethanol had a strong additive effect on colony growth in conventional air, but little or no effect in the low oxygen tension. These results suggest that enhancement of colony growth in the low oxygen tension may be due to a decrease in the production of oxygen

ISSN:0737-1454    

DOI:10.1002/stem.5530050506

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

年代:1987

数据来源: WILEY

摘要:

AbstractBecause of technical limitations with the human tumor colony‐forming assay (HTCFA), we determined the feasibility of using a thymidine incorporation assay (TIA) for new drug screening. Concordance between the TIA and the HTCFA was obtained (r = 0.840) with twenty coded compounds. Toxic agents without proven clinical efficacy were active in both assays, while non‐toxic substances were inactive. Growth rates were higher with the TIA (75%) than with the HTCFA (45%), and the TIA could be completed in 6 days compared to 14–21 days with the HTCFA. We concluded that the TIA is a useful adjunct to in vivo tumor models for screening new anticancer a

ISSN:0737-1454    

DOI:10.1002/stem.5530050507

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

年代:1987

数据来源: WILEY

ISSN:0737-1454    

DOI:10.1002/stem.5530050501

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

年代:1987

数据来源: WILEY