Involvement of the Retinoblastoma Protein in Monocytic and Neutrophilic Lineage Commitment of Human Bone Marrow Progenitor Cells

Blood ◽  
1999 ◽  
Vol 94 (6) ◽  
pp. 1971-1978 ◽  
Author(s):  
Gösta Bergh ◽  
Mats Ehinger ◽  
Inge Olsson ◽  
Sten Eirik W. Jacobsen ◽  
Urban Gullberg

Abstract The retinoblastoma gene product (pRb) is involved in both cell cycle regulation and cell differentiation. pRb may have dual functions during cell differentiation: partly by promoting a cell cycle brake at G1 and also by interacting with tissue-specific transcription factors. We recently showed that pRb mediates differentiation of leukemic cell lines involving mechanisms other than the induction of G1 arrest. In the present study, we investigated the role of pRb in differentiation of human bone marrow progenitor cells. Human bone marrow cells were cultured in a colony-forming unit–granulocyte-macrophage (CFU-GM) assay. The addition of antisense RB oligonucleotides (-RB), but not the addition of sense orientated oligonucleotides (SO) or scrambled oligonucleotides (SCR), reduced the number of colonies staining for nonspecific esterase without affecting the clonogenic growth. Monocytic differentiation of CD34+ cells supported by FLT3-ligand and interleukin-3 (IL-3) was correlated to high levels of hypophosphorylated pRb, whereas neutrophilic differentiation, supported by granulocyte colony-stimulating factor (G-CSF) and stem cell factor (SCF), was correlated to low levels. The addition of -RB to liquid cultures of CD34+ cells, supported with FLT3-ligand and IL-3, inhibited monocytic differentiation. This was judged by morphology, the expression of CD14, and staining for esterase. Moreover, the inhibition of monocytic differentiation of CD34+ cells mediated by -RB, which is capable of reducing pRb expression, was counterbalanced by an enhanced neutrophilic differentiation response, as judged by morphology and the expression of lactoferrin. CD34+ cells incubated with oligo buffer, -RB, SO, or SCR showed similar growth rates. Taken together, these data suggest that pRb plays a critical role in the monocytic and neutrophilic lineage commitment of human bone marrow progenitors, probably by mechanisms that are not strictly related to control of cell cycle progression.

Blood ◽  
1999 ◽  
Vol 94 (6) ◽  
pp. 1971-1978 ◽  
Author(s):  
Gösta Bergh ◽  
Mats Ehinger ◽  
Inge Olsson ◽  
Sten Eirik W. Jacobsen ◽  
Urban Gullberg

The retinoblastoma gene product (pRb) is involved in both cell cycle regulation and cell differentiation. pRb may have dual functions during cell differentiation: partly by promoting a cell cycle brake at G1 and also by interacting with tissue-specific transcription factors. We recently showed that pRb mediates differentiation of leukemic cell lines involving mechanisms other than the induction of G1 arrest. In the present study, we investigated the role of pRb in differentiation of human bone marrow progenitor cells. Human bone marrow cells were cultured in a colony-forming unit–granulocyte-macrophage (CFU-GM) assay. The addition of antisense RB oligonucleotides (-RB), but not the addition of sense orientated oligonucleotides (SO) or scrambled oligonucleotides (SCR), reduced the number of colonies staining for nonspecific esterase without affecting the clonogenic growth. Monocytic differentiation of CD34+ cells supported by FLT3-ligand and interleukin-3 (IL-3) was correlated to high levels of hypophosphorylated pRb, whereas neutrophilic differentiation, supported by granulocyte colony-stimulating factor (G-CSF) and stem cell factor (SCF), was correlated to low levels. The addition of -RB to liquid cultures of CD34+ cells, supported with FLT3-ligand and IL-3, inhibited monocytic differentiation. This was judged by morphology, the expression of CD14, and staining for esterase. Moreover, the inhibition of monocytic differentiation of CD34+ cells mediated by -RB, which is capable of reducing pRb expression, was counterbalanced by an enhanced neutrophilic differentiation response, as judged by morphology and the expression of lactoferrin. CD34+ cells incubated with oligo buffer, -RB, SO, or SCR showed similar growth rates. Taken together, these data suggest that pRb plays a critical role in the monocytic and neutrophilic lineage commitment of human bone marrow progenitors, probably by mechanisms that are not strictly related to control of cell cycle progression.


Blood ◽  
2000 ◽  
Vol 95 (2) ◽  
pp. 510-518 ◽  
Author(s):  
June Helen Myklebust ◽  
Erlend B. Smeland ◽  
Dag Josefsen ◽  
Mouldy Sioud

Protein kinase C (PKC) is a family of serine/threonine protein kinases involved in many cellular responses. Although the analysis of PKC activity in many systems has provided crucial insights to its biologic function, the precise role of different isoforms on the differentiation of normal hematopoietic progenitor cells into the various lineages remains to be investigated. The authors have assessed the state of activation and protein expression of PKC isoforms after cytokine stimulation of CD34+ progenitor cells from human bone marrow. Freshly isolated CD34+ cells were found to express PKC-, PKC-β2, and PKC-ɛ, whereas PKC-δ, PKC-γ, and PKC-ζ were not detected. Treatment with erythropoietin (EPO) or with EPO and stem cell factor (SCF) induced a predominantly erythroid differentiation of CD34+ cells that was accompanied by the up-regulation of PKC- and PKC-β2 protein levels (11.8- and 2.5-fold, respectively) compared with cells cultured in medium. Stimulation with EPO also resulted in the nuclear translocation of PKC- and PKC-β2 isoforms. Notably, none of the PKC isoforms tested were detectable in CD34+ cells induced to myeloid differentiation by G-CSF and SCF stimulation. The PKC inhibitors staurosporine and calphostin C prevented EPO-induced erythroid differentiation. Down-regulation of the PKC-, PKC-β2, and PKC-ɛ expression by TPA pretreatment, or the down-regulation of PKC- with a specific ribozyme, also inhibited the EPO-induced erythroid differentiation of CD34+ cells. No effect was seen with PKC-β2–specific ribozymes. Taken together, these findings point to a novel role for the PKC- isoform in mediating EPO-induced erythroid differentiation of the CD34+ progenitor cells from human bone marrow.


Blood ◽  
1998 ◽  
Vol 91 (6) ◽  
pp. 1947-1958 ◽  
Author(s):  
Katharina S. Götze ◽  
Manuel Ramı́rez ◽  
Kelly Tabor ◽  
Donald Small ◽  
William Matthews ◽  
...  

We generated monoclonal antibodies against the human Flt3 receptor and used them to study the characteristics of normal human bone marrow cells resolved based on Flt3 expression. Human CD34+ or CD34+lin− marrow cells were sorted into two populations: cells expressing high levels of Flt3 receptor (Flt3high) and cells with little or no expression of Flt3 receptor (Flt3low). Flt3 receptor was detected on a subset of CD34+CD38− marrow cells, as well as on CD34+CD19+ B lymphoid progenitors and CD34+CD14+CD64+ monocytic precursors. Flt3 receptor was also present on more mature CD34−CD14+ monocytes. In colony-forming assays, Flt3high cells gave rise mainly to colony-forming unit–granulocyte-macrophage (CFU-GM) colonies, whereas Flt3low cells produced mostly burst-forming unit-erythroid colonies. There was no difference in the number of multilineage CFU-Mix colonies between the two cell fractions. Cell cycle analysis showed that a large number of the Flt3low cells were in the G0 phase of the cell cycle, whereas Flt3highcells were predominantly in G1. Cell numbers in the suspension cultures initiated with Flt3high cells were maintained in the presence of Flt3 ligand (FL) alone, and increased in response to FL plus kit ligand (KL). In contrast, cell numbers in the suspension cultures started with Flt3low cells did not increase in the presence of FL, or FL plus KL. Upregulation of Flt3 receptor on Flt3low cells was not detected during suspension culture. CD14+ monocytes were the major cell type generated from CD34+lin−Flt3high cells in liquid suspension culture, whereas cells generated from CD34+lin−Flt3low cells were mainly CD71+GlycA+ erythroid cells. These results show clear functional differences between CD34+Flt3high and CD34+Flt3low cells and may have implications concerning the in vitro expansion of human hematopoietic progenitor cells.


Blood ◽  
1998 ◽  
Vol 91 (6) ◽  
pp. 1947-1958 ◽  
Author(s):  
Katharina S. Götze ◽  
Manuel Ramı́rez ◽  
Kelly Tabor ◽  
Donald Small ◽  
William Matthews ◽  
...  

Abstract We generated monoclonal antibodies against the human Flt3 receptor and used them to study the characteristics of normal human bone marrow cells resolved based on Flt3 expression. Human CD34+ or CD34+lin− marrow cells were sorted into two populations: cells expressing high levels of Flt3 receptor (Flt3high) and cells with little or no expression of Flt3 receptor (Flt3low). Flt3 receptor was detected on a subset of CD34+CD38− marrow cells, as well as on CD34+CD19+ B lymphoid progenitors and CD34+CD14+CD64+ monocytic precursors. Flt3 receptor was also present on more mature CD34−CD14+ monocytes. In colony-forming assays, Flt3high cells gave rise mainly to colony-forming unit–granulocyte-macrophage (CFU-GM) colonies, whereas Flt3low cells produced mostly burst-forming unit-erythroid colonies. There was no difference in the number of multilineage CFU-Mix colonies between the two cell fractions. Cell cycle analysis showed that a large number of the Flt3low cells were in the G0 phase of the cell cycle, whereas Flt3highcells were predominantly in G1. Cell numbers in the suspension cultures initiated with Flt3high cells were maintained in the presence of Flt3 ligand (FL) alone, and increased in response to FL plus kit ligand (KL). In contrast, cell numbers in the suspension cultures started with Flt3low cells did not increase in the presence of FL, or FL plus KL. Upregulation of Flt3 receptor on Flt3low cells was not detected during suspension culture. CD14+ monocytes were the major cell type generated from CD34+lin−Flt3high cells in liquid suspension culture, whereas cells generated from CD34+lin−Flt3low cells were mainly CD71+GlycA+ erythroid cells. These results show clear functional differences between CD34+Flt3high and CD34+Flt3low cells and may have implications concerning the in vitro expansion of human hematopoietic progenitor cells.


Blood ◽  
1998 ◽  
Vol 91 (10) ◽  
pp. 3693-3701 ◽  
Author(s):  
Ponnazhagan Veena ◽  
Christie M. Traycoff ◽  
David A. Williams ◽  
Jon McMahel ◽  
Susan Rice ◽  
...  

Abstract Primitive hematopoietic progenitor cells (HPCs) are potential targets for treatment of numerous hematopoietic diseases using retroviral-mediated gene transfer (RMGT). To achieve high efficiency of gene transfer into primitive HPCs, a delicate balance between cellular activation and proliferation and maintenance of hematopoietic potential must be established. We have demonstrated that a subpopulation of human bone marrow (BM) CD34+ cells, highly enriched for primitive HPCs, persists in culture in a mitotically quiescent state due to their cytokine-nonresponsive (CNR) nature, a characteristic that may prevent efficient RMGT of these cells. To evaluate and possibly circumvent this, we designed a two-step transduction protocol usingneoR-containing vectors coupled with flow cytometric cell sorting to isolate and examine transduction efficiency in different fractions of cultured CD34+ cells. BM CD34+ cells stained on day 0 (d0) with the membrane dye PKH2 were prestimulated for 24 hours with stem cell factor (SCF), interleukin-3 (IL-3), and IL-6, and then transduced on fibronectin with the retroviral vector LNL6 on d1. On d5, half of the cultured cells were transduced with the retroviral vector G1Na and sorted on d6 into cytokine-responsive (d6 CR) cells (detected via their loss of PKH2 fluorescence relative to d0 sample) and d6 CNR cells that had not divided since d0. The other half of the cultured cells were first sorted on d5 into d5 CR and d5 CNR cells and then infected separately with G1Na. Both sets of d5 and d6 CR and CNR cells were cultured in secondary long-term cultures (LTCs) and assayed weekly for transduced progenitor cells. Significantly higher numbers of G418-resistant colonies were produced in cultures initiated with d5 and d6 CNR cells compared with respective CR fractions (P < .05). At week 2, transduction efficiency was comparable between d5 and d6 transduced CR and CNR cells (P > .05). However, at weeks 3 and 4, d5 and d6 CNR fractions generated significantly higher numbers ofneoR progenitor cells relative to the respective CR fractions (P < .05), while no difference in transduction efficiency between d5 and d6 CNR cells could be demonstrated. Polymerase chain reaction (PCR) analysis of the origin of transducedneoR gene in clonogenic cells demonstrated that mature progenitors (CR fractions) contained predominantly LNL6 sequences, while more primitive progenitor cells (CNR fractions) were transduced with G1Na. These results demonstrate that prolonged stimulation of primitive HPCs is essential for achieving efficient RMGT into cells capable of sustaining long-term in vitro hematopoiesis. These findings may have significant implications for the development of clinical gene therapy protocols.


Blood ◽  
1997 ◽  
Vol 89 (2) ◽  
pp. 446-456 ◽  
Author(s):  
Mo A. Dao ◽  
Charles H. Hannum ◽  
Donald B. Kohn ◽  
Jan A. Nolta

Abstract Stromal support is required during retroviral-mediated transduction of human bone marrow-derived CD34+ cells to maintain the clonogenicity of the primitive progenitors. We hypothesized that the cytokine FLT3 ligand (FL) might be able to replace the maintenance role provided by the stroma. CD34+ progenitors from human bone marrow were transduced by the retroviral vector LN with the cytokines interleukin-3 (IL-3), IL-6, and stem cell factor (SCF ) present in all cultures. Transductions were performed with or without stromal support and with or without the inclusion of 100 U/mL FL. No significant increase in gene transfer into colony-forming cells was obtained by the addition of FL to the cultures. Transduction and survival of more primitive human hematopoietic cells was determined by growth in immune-deficient mice for 7 to 8 months. Human myeloid cells, T lymphocytes, and colony-forming progenitors were recovered from the marrow of mice that had received human cells transduced on stroma or in suspension culture with IL-3, IL-6, SCF, and FL, but not with IL-3, IL-6, and SCF alone. LN provirus was detected by polymerase chain reaction in the marrow recovered from 9 of 10 mice transplanted with human CD34+ cells transduced with stromal support, 5 of 11 mice that received human cells transduced in suspension culture with FL, but none of the 10 mice that received human cells transduced in suspension culture without FL. We conclude that FLT3 ligand, in conjunction with IL-3, IL-6, and SCF, preserves the generative capacity of primitive human hematopoietic cells during in vitro transductions in suspension culture.


2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Yuanyuan Zhang ◽  
Shasha Wang ◽  
Chunyan Chen ◽  
Xiao Wu ◽  
Qunye Zhang ◽  
...  

Arsenic trioxide exhibits therapeutic effects on certain blood malignancies, at least partly by modulating cell differentiation. Previousin vitrostudies in human hematopoietic progenitor cells have suggested that arsenic may inhibit erythroid differentiation. However, these effects were all observed in the presence of arsenic compounds, while the concomitant cytostatic and cytotoxic actions of arsenic might mask a prodifferentiating activity. To eliminate the potential impacts of the cytostatic and cytotoxic actions of arsenic, we adopted a novel protocol by pretreating human bone marrow CD34+ cells with a low, noncytotoxic concentration of arsenic trioxide, followed by assaying the colony forming activities in the absence of the arsenic compound. Bone marrow specimens were obtained from chronic myeloid leukemia patients who achieved complete cytogenetic remission. CD34+ cells were isolated by magnetic-activated cell sorting. We discovered that arsenic trioxide enhanced the erythroid colony forming activity, which was accompanied by a decrease in the granulomonocytic differentiation function. Moreover, in erythroleukemic K562 cells, we showed that arsenic trioxide inhibited erythrocyte maturation, suggesting that arsenic might have biphasic effects on erythropoiesis. In conclusion, our data provided the first evidence showing that arsenic trioxide could prime human hematopoietic progenitor cells for enhanced erythroid differentiation.


Blood ◽  
1998 ◽  
Vol 91 (10) ◽  
pp. 3693-3701
Author(s):  
Ponnazhagan Veena ◽  
Christie M. Traycoff ◽  
David A. Williams ◽  
Jon McMahel ◽  
Susan Rice ◽  
...  

Primitive hematopoietic progenitor cells (HPCs) are potential targets for treatment of numerous hematopoietic diseases using retroviral-mediated gene transfer (RMGT). To achieve high efficiency of gene transfer into primitive HPCs, a delicate balance between cellular activation and proliferation and maintenance of hematopoietic potential must be established. We have demonstrated that a subpopulation of human bone marrow (BM) CD34+ cells, highly enriched for primitive HPCs, persists in culture in a mitotically quiescent state due to their cytokine-nonresponsive (CNR) nature, a characteristic that may prevent efficient RMGT of these cells. To evaluate and possibly circumvent this, we designed a two-step transduction protocol usingneoR-containing vectors coupled with flow cytometric cell sorting to isolate and examine transduction efficiency in different fractions of cultured CD34+ cells. BM CD34+ cells stained on day 0 (d0) with the membrane dye PKH2 were prestimulated for 24 hours with stem cell factor (SCF), interleukin-3 (IL-3), and IL-6, and then transduced on fibronectin with the retroviral vector LNL6 on d1. On d5, half of the cultured cells were transduced with the retroviral vector G1Na and sorted on d6 into cytokine-responsive (d6 CR) cells (detected via their loss of PKH2 fluorescence relative to d0 sample) and d6 CNR cells that had not divided since d0. The other half of the cultured cells were first sorted on d5 into d5 CR and d5 CNR cells and then infected separately with G1Na. Both sets of d5 and d6 CR and CNR cells were cultured in secondary long-term cultures (LTCs) and assayed weekly for transduced progenitor cells. Significantly higher numbers of G418-resistant colonies were produced in cultures initiated with d5 and d6 CNR cells compared with respective CR fractions (P < .05). At week 2, transduction efficiency was comparable between d5 and d6 transduced CR and CNR cells (P > .05). However, at weeks 3 and 4, d5 and d6 CNR fractions generated significantly higher numbers ofneoR progenitor cells relative to the respective CR fractions (P < .05), while no difference in transduction efficiency between d5 and d6 CNR cells could be demonstrated. Polymerase chain reaction (PCR) analysis of the origin of transducedneoR gene in clonogenic cells demonstrated that mature progenitors (CR fractions) contained predominantly LNL6 sequences, while more primitive progenitor cells (CNR fractions) were transduced with G1Na. These results demonstrate that prolonged stimulation of primitive HPCs is essential for achieving efficient RMGT into cells capable of sustaining long-term in vitro hematopoiesis. These findings may have significant implications for the development of clinical gene therapy protocols.


Sign in / Sign up

Export Citation Format

Share Document