scholarly journals Stem cell factor increases colony-forming unit-spleen number in vitro in synergy with interleukin-6, and in vivo in Sl/Sld mice as a single factor

Blood ◽  
1992 ◽  
Vol 79 (4) ◽  
pp. 913-919 ◽  
Author(s):  
DM Bodine ◽  
D Orlic ◽  
NC Birkett ◽  
NE Seidel ◽  
KM Zsebo

Abstract Hematopoiesis is thought to be modulated by interactions of progenitor cells with hematopoietic growth factors. We have shown that colony- forming units-spleen (CFU-S) and repopulating stem cells require interleukin-3 (IL-3) to survive in vitro, and that CFU-S number and long-term repopulating ability can be increased by culture in the combination of IL-3 and IL-6. In this report, we describe the effects of stem cell factor (SCF) on CFU-S and repopulating stem cells. Injection of SCF into anemic Sl/Sld mice caused a twofold and 20-fold increase in CFU-S number in the bone marrow and spleen of treated animals, respectively. After 6 days in suspension culture, CFU-S number increased threefold in cultures supplemented with SCF and IL-6, or SCF, IL-3, and IL-6 relative to the number at day 0. The long-term repopulating ability of cells cultured in SCF, IL-3, and IL-6 was approximately sevenfold better than that of cells cultured in IL-3 or SCF. Similar experiments were performed on populations of bone marrow cells enriched for, or depleted of, CFU-S by elutriation and lineage subtraction. The combination of SCF and IL-6 increased CFU-S number approximately fourfold to eightfold in the CFU-S-enriched fraction, but had no effect on the CFU-S-depleted cells. These results show that SCF alone can increase CFU-S number in vivo, and in combination with other growth factors increases CFU-S numbers in vitro.

Blood ◽  
1992 ◽  
Vol 79 (4) ◽  
pp. 913-919 ◽  
Author(s):  
DM Bodine ◽  
D Orlic ◽  
NC Birkett ◽  
NE Seidel ◽  
KM Zsebo

Hematopoiesis is thought to be modulated by interactions of progenitor cells with hematopoietic growth factors. We have shown that colony- forming units-spleen (CFU-S) and repopulating stem cells require interleukin-3 (IL-3) to survive in vitro, and that CFU-S number and long-term repopulating ability can be increased by culture in the combination of IL-3 and IL-6. In this report, we describe the effects of stem cell factor (SCF) on CFU-S and repopulating stem cells. Injection of SCF into anemic Sl/Sld mice caused a twofold and 20-fold increase in CFU-S number in the bone marrow and spleen of treated animals, respectively. After 6 days in suspension culture, CFU-S number increased threefold in cultures supplemented with SCF and IL-6, or SCF, IL-3, and IL-6 relative to the number at day 0. The long-term repopulating ability of cells cultured in SCF, IL-3, and IL-6 was approximately sevenfold better than that of cells cultured in IL-3 or SCF. Similar experiments were performed on populations of bone marrow cells enriched for, or depleted of, CFU-S by elutriation and lineage subtraction. The combination of SCF and IL-6 increased CFU-S number approximately fourfold to eightfold in the CFU-S-enriched fraction, but had no effect on the CFU-S-depleted cells. These results show that SCF alone can increase CFU-S number in vivo, and in combination with other growth factors increases CFU-S numbers in vitro.


Blood ◽  
1994 ◽  
Vol 84 (2) ◽  
pp. 421-432 ◽  
Author(s):  
D DiGiusto ◽  
S Chen ◽  
J Combs ◽  
S Webb ◽  
R Namikawa ◽  
...  

Experimentation on human stem cells is hampered by the relative paucity of this population and by the lack of assays identifying multilineage differentiation, particularly along the lymphoid lineages. In our current study, phenotypic analysis of low-density fetal bone marrow cells showed two distinct populations of CD34+ cells: those expressing a high density of CD34 antigen on their surface (CD34hi) and those expressing an intermediate level of CD34 antigen (CD34lo). Multiple tissues were used to characterize the in vitro and in vivo potential of these subsets and showed that only CD34hi cells support long-term B lymphopoiesis and myelopoiesis in vitro and mediate T, B, and myeloid repopulation of human tissues implanted into SCID mice. CD34lo cells repeatedly failed to provide long-term hematopoietic activity in vivo or in vitro. These results indicate that a simple fractionation based on well-defined CD34 antigen levels can be used to reproducibly isolate cells highly enriched for in vivo long-term repopulating activity and for multipotent progenitors, including T- and B-cell precursors. Additionally, given the limited variability in the results and the high correlation between in vitro and in vivo hematopoietic potential, we propose that the CD34hi population contains virtually all of the stem cell activity in fetal bone marrow and therefore is the population of choice for future studies in hematopoietic stem cell development and gene therapy.


Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 194-194 ◽  
Author(s):  
Lars U.W. Muller ◽  
Michael Milsom ◽  
Chad E. Harris ◽  
Jeff Bailey ◽  
David A. Williams

Abstract Fanconi anemia (FA) is amenable to genetic correction of hematopoietic stem cells (HSCs). However, as demonstrated in previous clinical gene therapy trials, successful extension of murine studies into human therapies is limited by low numbers of target HSC and poor engraftment of transduced FA HSC (Kelly et al., Mol Ther, 2007). To examine the potential biological consequences/benefits of shortened transduction we used a FA mouse model in which HSC are deficient and prone to excessive loss during in vitro manipulation. We applied a rapid transduction protocol (Mostoslavsky et al., Mol Ther, 2005) utilizing lentiviral vectors and demonstrate that this shortened transduction preserves engraftment of FA HSC to the level of C57BL/6 wt cells. Lin− Sca-1+ c-Kit+ bone marrow cells were isolated from Fanca−/− CD45.2 mice and underwent 4-hr rapid (RT) vs. 96-hr conventional (CT) transduction. An equivalent number of transduced cells were transplanted into lethally irradiated CD45.1 BoyJ mice. Analysis of engraftment chimerism three months post transplantation revealed a significantly higher level of engraftment in animals receiving RT vs. CT cells (90% +/− 14% vs. 26% +/− 31%, respectively, p=<0.01). Rapid transduction also resulted in a significant reduction of engraftment failure (0/36 animals RT vs. 20/36 animals CT). Importantly--emphasizing the FA disease-specific stem cell phenotype, RT vs. CT of C57BL/6 wt cells was associated with no significant difference in engraftment of these cells (93% +/− 1.2% RT vs. 84 +/− 19% CT, p=0.33). Analysis of peripheral blood cells expressing the proviral enhanced green fluorescent protein (eGFP) reporter gene revealed a normal distribution of B-lymphocytes (B220), T-lymphocytes (CD3 epsilon), and granulocytes (MAC-1), indicating multi-lineage engraftment of gene modified cells. In spite of this engraftment advantage, transduction efficiency was low (<30%) using RT. The 6-benzylguanine (6-BG) resistant P140K mutant of O6-methylguanine DNA methyltransferase (MGMTP140K) confers a selective advantage to tranduced HSC treated with alkylating drugs. Following RT with a MGMTP140K/ eGFP expressing lentivirus, 5/6 mice treated with 6-BG and the alkylating drug temozolomide showed a significant rise in the percentage of GFP reporter gene expression in peripheral blood. We extended this approach to the FA model by generating a tri-cistronic lentiviral vector expressing the FANCA cDNA, MGMTP140K, and eGFP. Despite modest in vivo gene marking with this vector, up to 37-fold selection (85% GFP-positive cells) was achieved following exposure of bone marrow of transplant recipients to 6-BG and the alkylating drug temozolomide in vitro. Concurrently, phenotypic correction of mitomycin C hypersensitivity of transduced Fanca−/− bone marrow cells was observed. These data suggest that RT improves stem cell engrafting capacity of FA stem cells in a relevant animal model of stem cell gene therapy. The combination of RT and in vivo selection may allow more successful reconstitution of the lympho-hematopoietic system in gene therapy applications.


Blood ◽  
1991 ◽  
Vol 78 (10) ◽  
pp. 2527-2533 ◽  
Author(s):  
RE Ploemacher ◽  
JP van der Sluijs ◽  
CA van Beurden ◽  
MR Baert ◽  
PL Chan

Abstract We have developed an in vitro clonal assay of murine hematopoietic precursor cells that form spleen colonies (CFU-S day 12) or produce in vitro clonable progenitors in the marrow (MRA cells) of lethally irradiated mice. The assay is essentially a long-term bone marrow culture in microtiter wells containing marrow-derived stromal “feeders” depleted for hematopoietic activity by irradiation. To test the validity of the assay as a quantitative in vitro stem cell assay, a series of unsorted and physically sorted bone marrow cells were simultaneously assayed in vivo and overlaid on the feeders in a range of concentrations, while frequencies of cells forming hematopoietic clones (cobblestone area forming cells, CAFC) were calculated by means of Poisson statistics. Linear regression analysis of the data showed high correlations between the frequency of CFU-S day 12 and CAFC day 10, and between MRA cells and CAFC day 28. A majority of MRA activity and CAFC day 28 was separable from CFU-S day 12 and CAFC day 10. This correlation study validates the CAFC system as a clonal assay facilitation both the quantitative assessment of a series of subsets in the hematopoietic stem cell hierarchy and the study of single long-term repopulating cells in vitro.


Blood ◽  
1991 ◽  
Vol 78 (10) ◽  
pp. 2527-2533 ◽  
Author(s):  
RE Ploemacher ◽  
JP van der Sluijs ◽  
CA van Beurden ◽  
MR Baert ◽  
PL Chan

We have developed an in vitro clonal assay of murine hematopoietic precursor cells that form spleen colonies (CFU-S day 12) or produce in vitro clonable progenitors in the marrow (MRA cells) of lethally irradiated mice. The assay is essentially a long-term bone marrow culture in microtiter wells containing marrow-derived stromal “feeders” depleted for hematopoietic activity by irradiation. To test the validity of the assay as a quantitative in vitro stem cell assay, a series of unsorted and physically sorted bone marrow cells were simultaneously assayed in vivo and overlaid on the feeders in a range of concentrations, while frequencies of cells forming hematopoietic clones (cobblestone area forming cells, CAFC) were calculated by means of Poisson statistics. Linear regression analysis of the data showed high correlations between the frequency of CFU-S day 12 and CAFC day 10, and between MRA cells and CAFC day 28. A majority of MRA activity and CAFC day 28 was separable from CFU-S day 12 and CAFC day 10. This correlation study validates the CAFC system as a clonal assay facilitation both the quantitative assessment of a series of subsets in the hematopoietic stem cell hierarchy and the study of single long-term repopulating cells in vitro.


Blood ◽  
1996 ◽  
Vol 87 (1) ◽  
pp. 30-37 ◽  
Author(s):  
SO Peters ◽  
EL Kittler ◽  
HS Ramshaw ◽  
PJ Quesenberry

Abstract In vitro incubation of bone marrow cells with cytokines has been used as an approach to expand stem cells and to facilitate retroviral integration. Expansion of hematopoietic progenitor cells has been monitored by different in vitro assays and in a few instances by in vivo marrow renewal in myeloablated hosts. This is the first report of studies, using two competitive transplant models, in which cytokine-treated cells, obtained from nonpretreated donors (eg, 5-fluorouracil), were competed with normal cells. A basic assumption is that the expansion of progenitors assayed in vitro as high- and low-proliferative potential colony-forming cells (HPP- and LPP-CFCs) indicates an expansion of stem cells which will repopulate in vivo. This study shows that culture of marrow cells with four cytokines (stem cell factor, interleukin-3 [IL-3], IL-6, IL-11) induces significant expansion and proliferation of HPP-CFC and LPP-CFC. Cell-cycle analysis showed that these hematopoietic progenitors were induced to actively cell cycle by culture with these cytokines. In the first competitive transplant model, which uses Ly5.2/Ly5.1 congenic mice, cytokine-cultured Ly5.2 cells competed with noncultured Ly5.1 cells led to 5% +/- 1% engraftment at 12 weeks and to 4% +/- 2% engraftment at 22 weeks posttransplantation for the cytokine exposed cells. Noncultured Ly5.2 cells competed with cultured Ly5.1 cells led to 70% +/- 1% engraftment at 12 weeks and to 93% +/- 2% engraftment at 22 weeks posttransplantation. In the second model, which uses BALB/c marrow of opposite genders, cultured male cells lead to 13% +/- 9% engraftment at 10 weeks and 2% +/- 1% engraftment at 14 weeks posttransplantation; noncultured male cells lead to 70% +/- 2% and 95% +/- 2% engraftment at 10 and 14 weeks posttransplantation, respectively. Data presented here from two different competitive transplant studies show a defect of cytokine expanded marrow related to cell cycle activation which manifests as defective long-term repopulating capability in irradiated host mice. The engraftment defect is more profound at longer time intervals, suggesting that the most striking effect may be on long-term repopulating cells.


Blood ◽  
1994 ◽  
Vol 84 (2) ◽  
pp. 421-432 ◽  
Author(s):  
D DiGiusto ◽  
S Chen ◽  
J Combs ◽  
S Webb ◽  
R Namikawa ◽  
...  

Abstract Experimentation on human stem cells is hampered by the relative paucity of this population and by the lack of assays identifying multilineage differentiation, particularly along the lymphoid lineages. In our current study, phenotypic analysis of low-density fetal bone marrow cells showed two distinct populations of CD34+ cells: those expressing a high density of CD34 antigen on their surface (CD34hi) and those expressing an intermediate level of CD34 antigen (CD34lo). Multiple tissues were used to characterize the in vitro and in vivo potential of these subsets and showed that only CD34hi cells support long-term B lymphopoiesis and myelopoiesis in vitro and mediate T, B, and myeloid repopulation of human tissues implanted into SCID mice. CD34lo cells repeatedly failed to provide long-term hematopoietic activity in vivo or in vitro. These results indicate that a simple fractionation based on well-defined CD34 antigen levels can be used to reproducibly isolate cells highly enriched for in vivo long-term repopulating activity and for multipotent progenitors, including T- and B-cell precursors. Additionally, given the limited variability in the results and the high correlation between in vitro and in vivo hematopoietic potential, we propose that the CD34hi population contains virtually all of the stem cell activity in fetal bone marrow and therefore is the population of choice for future studies in hematopoietic stem cell development and gene therapy.


Blood ◽  
1996 ◽  
Vol 87 (1) ◽  
pp. 30-37 ◽  
Author(s):  
SO Peters ◽  
EL Kittler ◽  
HS Ramshaw ◽  
PJ Quesenberry

In vitro incubation of bone marrow cells with cytokines has been used as an approach to expand stem cells and to facilitate retroviral integration. Expansion of hematopoietic progenitor cells has been monitored by different in vitro assays and in a few instances by in vivo marrow renewal in myeloablated hosts. This is the first report of studies, using two competitive transplant models, in which cytokine-treated cells, obtained from nonpretreated donors (eg, 5-fluorouracil), were competed with normal cells. A basic assumption is that the expansion of progenitors assayed in vitro as high- and low-proliferative potential colony-forming cells (HPP- and LPP-CFCs) indicates an expansion of stem cells which will repopulate in vivo. This study shows that culture of marrow cells with four cytokines (stem cell factor, interleukin-3 [IL-3], IL-6, IL-11) induces significant expansion and proliferation of HPP-CFC and LPP-CFC. Cell-cycle analysis showed that these hematopoietic progenitors were induced to actively cell cycle by culture with these cytokines. In the first competitive transplant model, which uses Ly5.2/Ly5.1 congenic mice, cytokine-cultured Ly5.2 cells competed with noncultured Ly5.1 cells led to 5% +/- 1% engraftment at 12 weeks and to 4% +/- 2% engraftment at 22 weeks posttransplantation for the cytokine exposed cells. Noncultured Ly5.2 cells competed with cultured Ly5.1 cells led to 70% +/- 1% engraftment at 12 weeks and to 93% +/- 2% engraftment at 22 weeks posttransplantation. In the second model, which uses BALB/c marrow of opposite genders, cultured male cells lead to 13% +/- 9% engraftment at 10 weeks and 2% +/- 1% engraftment at 14 weeks posttransplantation; noncultured male cells lead to 70% +/- 2% and 95% +/- 2% engraftment at 10 and 14 weeks posttransplantation, respectively. Data presented here from two different competitive transplant studies show a defect of cytokine expanded marrow related to cell cycle activation which manifests as defective long-term repopulating capability in irradiated host mice. The engraftment defect is more profound at longer time intervals, suggesting that the most striking effect may be on long-term repopulating cells.


1968 ◽  
Vol 127 (4) ◽  
pp. 731-748 ◽  
Author(s):  
Tom R. DeMeester ◽  
Norman D. Anderson ◽  
Charles F. Shaffer

The present study has demonstrated that rabbit anti-mouse lymphocyte serum (RAMLS) has the capability of destroying bone marrow cells and suppressing hemopoietic stem cell function. The in vitro incubation of bone marrow suspensions with RAMLS caused extensive cell lysis with an apparent preferential destruction of lymphoid, erythroid, and blastoid elements. Using the spleen colony assay, the number of functional hemopoietic stem cells was found to be markedly reduced in bone marrow populations exposed to RAMLS in vitro. Further, this loss of stem cell function could be produced by exposing marrow suspensions to small concentrations of antiserum which did not produce detectable cytotoxic effects on the general marrow population. A similar effect of RAMLS upon hemopoietic stem cells was found in vivo. The intravenous injection of RAMLS into lethally irradiated mice immediately after the infusion of isogeneic marrow cells reduced the number of spleen colonies formed, indicating that the antiserum could exhibit a deleterious effect upon stem cells in the bloodstream of the intact animal. Normal animals treated with daily subcutaneous injections of RAMLS for 3 wk had a significantly reduced marrow content of functional hemopoietic stem cells, suggesting that RAMLS can affect stem cells located in situ in the bone marrow. The experiments indicate that RAMLS possesses potential marrow toxicity.


Sign in / Sign up

Export Citation Format

Share Document