摘要:

AbstractVascular endothelial cells elaborate growth factors which support the proliferation and differentiation of hematopoietic progenitor cells. Both the regulation and potential biological significance of growth factor production by endothelial cells are reviewed.

ISSN:0737-1454    

DOI:10.1002/stem.5530060502

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

年代:1988

数据来源: WILEY

摘要:

AbstractA highly efficient cloning system for in vitro myeloma colony growth could be valuable for screening antineoplastic agents in resistant patients and for testing the effects of purging methods in the context of autologous bone marrow transplantation. In this paper we report the results of experiments intended to improve the myeloma cloning system in plasma clot originally described by Ludwig et al. We tested the effects of the addition of phytohemagglutinin (PHA), coupled with a transformation of the original plasma clot method into a liquid culture system.A statistically higher number of myeloma colonies was observed in the liquid system in the presence of PHA (20 cases, median 84.5 vs. 9.5; p = 0.005), whereas a single variant (either PHA alone or liquid system alone) did not determine any significant growth variation. The increase in the cloning efficiency was evident even in the cases characterized by low bone marrow plasma cell infiltration, suggesting that this method is suitable for the described purposes.

ISSN:0737-1454    

DOI:10.1002/stem.5530060503

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

年代:1988

数据来源: WILEY

摘要:

AbstractClass I and Class II human alloreactive T cell clones or their conditioned media were mixed with progenitor cell‐enriched null cells to assess their ability to stimulate human hematopoietic progenitor cell (HPC) growth. Optimal release of erythroid, myeloid or megakaryocyte colony‐stimulating factors occurred after 72 hours and required contact of cloned T cells with irradiated stimulator cells expressing the appropriate major histocompatibility complex (MHC) determinants recognized by the T cells. Individual clones were quite heterogeneous in their capacity to release hematopoeitic growth factors. Clones that produced optimal levels of factors that stimulated granulocyte‐macrophage colony growth did not always produce equivalent amounts of factors that stimulated erythroid colony growth and vice versa when tested against identical target cells. Class II clones released nearly twice as much interleukin 3 activity as Class I clones. Class II clones that lacked cell‐mediated lympholytic (CML) activity against B or T lymphoblastoid targets were consistent stimulators of HPC growth. In contrast, Class I or Class II clones that contained CML activity either poorly stimulated or inhibited HPC growth. These CML‐positive clones produced greater amounts of gamma interferon. Our findings may have important implications for HPC growth following allogeneic mismatched bone marrow transp

ISSN:0737-1454    

DOI:10.1002/stem.5530060504

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

年代:1988

数据来源: WILEY

摘要:

AbstractMembrane expression of Fc receptors (FcR) was studied in clones of human K562 cells during short‐ and long‐term culture. Using a manual cloning method, well‐defined clones were generated either from FcR‐positive or FcR‐negative cells. The fourth day after cloning, the majority of cloned cells manifested shifts in FcR expression without evidence of an orderly pattern. After long‐term culture (about 34 passages), most clones expressed FcR values close to those found in the cell line. In addition, the selection of six clones expressing a stable FcR phenotype suggested that the presence of FcR is correlated to a low hemoglobinization of the multipotential

ISSN:0737-1454    

DOI:10.1002/stem.5530060505

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

年代:1988

数据来源: WILEY

摘要:

AbstractOver 80 human T helper cell (Th) clones reactive with human cytomegalovirus (HCMV) were generated using purified whole Towne strain HCMV as the in vitro antigen. These cloned T cells are CD3+, CD4+, CD8‐and proliferate specifically to HCMV. All of the clones tested produce interleukin 2 and gamma‐interferon and failed to show HCMV‐specific cytotoxicity or natural killer (NK) activity. Most of the Thclones recognize multiple laboratory‐adapted and wild‐type strains of HCMV. The Thclones were also tested for their reactivity to a major envelope glycoprotein complex (gcl) and a 64,000 dalton internal matrix protein. Our results show that both proteins as well as other unidentified protein(s) are involved in Thresponse

ISSN:0737-1454    

DOI:10.1002/stem.5530060506

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

年代:1988

数据来源: WILEY

ISSN:0737-1454    

DOI:10.1002/stem.5530060501

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

年代:1988

数据来源: WILEY