Gene transfer into hematopoietic stem cells: long-term maintenance of in vitro activated progenitors without marrow ablation.

AbstractA major limitation of current lentiviral vectors (LVs) is their inability to govern efficient gene transfer into quiescent cells, such as human CD34+ cells, that reside in the G0 phase of the cell cycle and that are highly enriched in hematopoietic stem cells. This hampers their application for gene therapy of hematopoietic cells. Here, we designed novel LVs that overcome this restriction by displaying “early-acting cytokines” on their surface. Display of thrombopoietin, stem cell factor, or both cytokines on the LV surface allowed efficient gene delivery into quiescent cord blood CD34+ cells. Moreover, these surface-engineered LVs preferentially transduced and promoted survival of resting CD34+ cells rather than cycling cells. Finally, and most importantly, these novel LVs allowed superior gene transfer in the most immature CD34+ cells as compared to conventional LVs, even when the latter vectors were used to transduce cells in the presence of recombinant cytokines. This was demonstrated by their capacity to promote selective transduction of CD34+ cell in in vitro derived long-term culture-initiating cell (LTC-IC) colonies and of long-term NOD/SCID repopulating cells (SRCs) in vivo.

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Strategies to Protect Hematopoietic Stem Cells from Culture-Induced Stress Conditions

Current Stem Cell Research & Therapy ◽

10.2174/1574888x15666200225091339 ◽

2020 ◽

Vol 15 ◽

Author(s):

Fatima Aerts-Kaya

Keyword(s):

Stem Cells ◽

Hematopoietic Stem Cells ◽

Ex Vivo ◽

Stress Conditions ◽

Stress Factors ◽

Hematopoietic Stem ◽

Induced Stress

: In contrast to their almost unlimited potential for expansion in vivo and despite years of dedicated research and optimization of expansion protocols, the expansion of Hematopoietic Stem Cells (HSCs) in vitro remains remarkably limited. Increased understanding of the mechanisms that are involved in maintenance, expansion and differentiation of HSCs will enable the development of better protocols for expansion of HSCs. This will allow procurement of HSCs with long-term engraftment potential and a better understanding of the effects of the external influences in and on the hematopoietic niche that may affect HSC function. During collection and culture of HSCs, the cells are exposed to suboptimal conditions that may induce different levels of stress and ultimately affect their self-renewal, differentiation and long-term engraftment potential. Some of these stress factors include normoxia, oxidative stress, extra-physiologic oxygen shock/stress (EPHOSS), endoplasmic reticulum (ER) stress, replicative stress, and stress related to DNA damage. Coping with these stress factors may help reduce the negative effects of cell culture on HSC potential, provide a better understanding of the true impact of certain treatments in the absence of confounding stress factors. This may facilitate the development of better ex vivo expansion protocols of HSCs with long-term engraftment potential without induction of stem cell exhaustion by cellular senescence or loss of cell viability. This review summarizes some of available strategies that may be used to protect HSCs from culture-induced stress conditions.

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Hlf Expression Marks Early Emergence of Hematopoietic Stem Cell Precursors With Adult Repopulating Potential and Fate

Frontiers in Cell and Developmental Biology ◽

10.3389/fcell.2021.728057 ◽

2021 ◽

Vol 9 ◽

Author(s):

Wanbo Tang ◽

Jian He ◽

Tao Huang ◽

Zhijie Bai ◽

Chaojie Wang ◽

...

Keyword(s):

Stem Cells ◽

Mouse Model ◽

Hematopoietic Stem Cells ◽

Fetal Liver ◽

Lineage Tracing ◽

Genetic Lineage ◽

Hematopoietic Stem ◽

Genetic Lineage Tracing

In the aorta-gonad-mesonephros (AGM) region of mouse embryos, pre-hematopoietic stem cells (pre-HSCs) are generated from rare and specialized hemogenic endothelial cells (HECs) via endothelial-to-hematopoietic transition, followed by maturation into bona fide hematopoietic stem cells (HSCs). As HECs also generate a lot of hematopoietic progenitors not fated to HSCs, powerful tools that are pre-HSC/HSC-specific become urgently critical. Here, using the gene knockin strategy, we firstly developed an Hlf-tdTomato reporter mouse model and detected Hlf-tdTomato expression exclusively in the hematopoietic cells including part of the immunophenotypic CD45– and CD45+ pre-HSCs in the embryonic day (E) 10.5 AGM region. By in vitro co-culture together with long-term transplantation assay stringent for HSC precursor identification, we further revealed that unlike the CD45– counterpart in which both Hlf-tdTomato-positive and negative sub-populations harbored HSC competence, the CD45+ E10.5 pre-HSCs existed exclusively in Hlf-tdTomato-positive cells. The result indicates that the cells should gain the expression of Hlf prior to or together with CD45 to give rise to functional HSCs. Furthermore, we constructed a novel Hlf-CreER mouse model and performed time-restricted genetic lineage tracing by a single dose induction at E9.5. We observed the labeling in E11.5 AGM precursors and their contribution to the immunophenotypic HSCs in fetal liver (FL). Importantly, these Hlf-labeled early cells contributed to and retained the size of the HSC pool in the bone marrow (BM), which continuously differentiated to maintain a balanced and long-term multi-lineage hematopoiesis in the adult. Therefore, we provided another valuable mouse model to specifically trace the fate of emerging HSCs during development.

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Long-Term Ex Vivo Maintenance and Expansion of Transplantable Human Hematopoietic Stem Cells

Blood ◽

10.1182/blood.v94.5.1623 ◽

1999 ◽

Vol 94 (5) ◽

pp. 1623-1636 ◽

Cited By ~ 72

Author(s):

Chu-Chih Shih ◽

Mickey C.-T. Hu ◽

Jun Hu ◽

Jeffrey Medeiros ◽

Stephen J. Forman

Keyword(s):

Stem Cells ◽

Hematopoietic Stem Cells ◽

In Vitro Culture ◽

Culture System ◽

Ex Vivo ◽

Human Stem Cells ◽

Hematopoietic Stem ◽

In Vitro Culture System

Abstract We have developed a stromal-based in vitro culture system that facilitates ex vivo expansion of transplantable CD34+thy-1+ cells using long-term hematopoietic reconstitution in severe combined immunodeficient-human (SCID-hu) mice as an in vivo assay for transplantable human hematopoietic stem cells (HSCs). The addition of leukemia inhibitory factor (LIF) to purified CD34+ thy-1+ cells on AC6.21 stroma, a murine bone marrow–derived stromal cell line, caused expansion of cells with CD34+ thy-1+ phenotype. Addition of other cytokines, including interleukin-3 (IL-3), IL-6, granulocyte-macrophage colony-stimulating factor, and stem cell factor, to LIF in the cultures caused a 150-fold expansion of cells retaining the CD34+ thy-1+ phenotype. The ex vivo–expanded CD34+ thy-1+ cells gave rise to multilineage differentiation, including myeloid, T, and B cells, when transplanted into SCID-hu mice. Both murine LIF (cannot bind to human LIF receptor) and human LIF caused expansion of human CD34+ thy-1+ cells in vitro, suggesting action through the murine stroma. Furthermore, another human HSC candidate, CD34+ CD38− cells, shows a similar pattern of proliferative response. This suggests thatex vivo expansion of transplantable human stem cells under this in vitro culture system is a general phenomenon and not just specific for CD34+ thy-1+ cells.

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Reversible Expression of CD34 by Murine Hematopoietic Stem Cells

Blood ◽

10.1182/blood.v94.8.2548.420k38_2548_2554 ◽

1999 ◽

Vol 94 (8) ◽

pp. 2548-2554 ◽

Cited By ~ 291

Author(s):

Takashi Sato ◽

Joseph H. Laver ◽

Makio Ogawa

Keyword(s):

Stem Cells ◽

Hematopoietic Stem Cells ◽

Bone Marrow Cells ◽

Cell Populations ◽

Hematopoietic Stem ◽

Adult Mice ◽

Cd34 Expression ◽

Marrow Cells

We used a mouse transplantation model to address the recent controversy about CD34 expression by hematopoietic stem cells. Cells from Ly-5.1 C57BL/6 mice were used as donor cells and Ly-5.2 mice were the recipients. The test cells were transplanted together with compromised marrow cells of Ly-5.2 mice. First, we confirmed that the majority of the stem cells with long-term engraftment capabilities of normal adult mice are CD34−. We then observed that, after the injection of 150 mg/kg 5-fluorouracil (5-FU), stem cells may be found in both CD34− and CD34+ cell populations. These results indicated that activated stem cells express CD34. We tested this hypothesis also by using in vitro expansion with interleukin-11 and steel factor of lineage−c-kit+ Sca-1+ CD34− bone marrow cells of normal mice. When the cells expanded for 1 week were separated into CD34− and CD34+ cell populations and tested for their engraftment capabilities, only CD34+ cells were capable of 2 to 5 months of engraftment. Finally, we tested reversion of CD34+ stem cells to CD34− state. We transplanted Ly-5.1 CD34+post–5-FU marrow cells into Ly-5.2 primary recipients and, after the marrow achieved steady state, tested the Ly-5.1 cells of the primary recipients for their engraftment capabilities in Ly-5.2 secondary recipients. The majority of the Ly-5.1 stem cells with long-term engraftment capability were in the CD34− cell fraction, indicating the reversion of CD34+ to CD34−stem cells. These observations clearly demonstrated that CD34 expression reflects the activation state of hematopoietic stem cells and that this is reversible.

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Expression of Human Glucocerebrosidase in Long-Term Reconstituted Mice Following Retroviral-Mediated Gene Transfer into Hematopoietic Stem Cells

Human Gene Therapy ◽

10.1089/hum.1990.1.3-277 ◽

1990 ◽

Vol 1 (3) ◽

pp. 277-287 ◽

Cited By ~ 18

Author(s):

Pamela H. Correll ◽

Yvonne Kew ◽

Leland K. Perry ◽

Roscoe O. Brady ◽

John K. Fink ◽

...

Keyword(s):

Stem Cells ◽

Gene Transfer ◽

Hematopoietic Stem Cells ◽

Hematopoietic Stem

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The chemokine GROβ mobilizes early hematopoietic stem cells characterized by enhanced homing and engraftment

Blood ◽

10.1182/blood-2006-06-031401 ◽

2007 ◽

Vol 110 (3) ◽

pp. 860-869 ◽

Cited By ~ 62

Author(s):

Seiji Fukuda ◽

Huimin Bian ◽

Andrew G. King ◽

Louis M. Pelus

Keyword(s):

Stem Cells ◽

Hematopoietic Stem Cells ◽

Hematopoietic Stem ◽

Platelet Recovery ◽

And Function ◽

Stimulating Factor ◽

Cxcr4 Axis

Abstract Mobilized peripheral blood hematopoietic stem cells (PBSCs) demonstrate accelerated engraftment compared with bone marrow; however, mechanisms responsible for enhanced engraftment remain unknown. PBSCs mobilized by GROβ (GROβΔ4/CXCL2Δ4) or the combination of GROβΔ4 plus granulocyte colony-stimulating factor (G-CSF) restore neutrophil and platelet recovery faster than G-CSF–mobilized PBSCs. To determine mechanisms responsible for faster hematopoietic recovery, we characterized immunophenotype and function of the GROβ-mobilized grafts. PBSCs mobilized by GROβΔ4 alone or with G-CSF contained significantly more Sca-1+-c-kit+-lineage− (SKL) cells and more primitive CD34−-SKL cells compared with cells mobilized by G-CSF and demonstrated superior competitive long-term repopulation activity, which continued to increase in secondary and tertiary recipients. GROβΔ4-mobilized SKL cells adhered better to VCAM-1+ endothelial cells compared with G-CSF–mobilized cells. GROβΔ4-mobilized PBSCs did not migrate well to the chemokine stromal derived factor (SDF)-1α in vitro that was associated with higher CD26 expression. However, GROβΔ4-mobilized SKL and c-Kit+ lineage− (KL) cells homed more efficiently to marrow in vivo, which was not affected by selective CXCR4 and CD26 antagonists. These data suggest that GROβΔ4-mobilized PBSCs are superior in reconstituting long-term hematopoiesis, which results from differential mobilization of early stem cells with enhanced homing and long-term repopulating capacity. In addition, homing and engraftment of GROβΔ4-mobilized cells is less dependent on the SDF-1α/CXCR4 axis.

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Long-Term Ex Vivo Maintenance and Expansion of Transplantable Human Hematopoietic Stem Cells

Blood ◽

10.1182/blood.v94.5.1623.417k34_1623_1636 ◽

1999 ◽

Vol 94 (5) ◽

pp. 1623-1636 ◽

Cited By ~ 1

Author(s):

Chu-Chih Shih ◽

Mickey C.-T. Hu ◽

Jun Hu ◽

Jeffrey Medeiros ◽

Stephen J. Forman

Keyword(s):

Stem Cells ◽

Hematopoietic Stem Cells ◽

In Vitro Culture ◽

Culture System ◽

Ex Vivo ◽

Human Stem Cells ◽

Hematopoietic Stem ◽

In Vitro Culture System

We have developed a stromal-based in vitro culture system that facilitates ex vivo expansion of transplantable CD34+thy-1+ cells using long-term hematopoietic reconstitution in severe combined immunodeficient-human (SCID-hu) mice as an in vivo assay for transplantable human hematopoietic stem cells (HSCs). The addition of leukemia inhibitory factor (LIF) to purified CD34+ thy-1+ cells on AC6.21 stroma, a murine bone marrow–derived stromal cell line, caused expansion of cells with CD34+ thy-1+ phenotype. Addition of other cytokines, including interleukin-3 (IL-3), IL-6, granulocyte-macrophage colony-stimulating factor, and stem cell factor, to LIF in the cultures caused a 150-fold expansion of cells retaining the CD34+ thy-1+ phenotype. The ex vivo–expanded CD34+ thy-1+ cells gave rise to multilineage differentiation, including myeloid, T, and B cells, when transplanted into SCID-hu mice. Both murine LIF (cannot bind to human LIF receptor) and human LIF caused expansion of human CD34+ thy-1+ cells in vitro, suggesting action through the murine stroma. Furthermore, another human HSC candidate, CD34+ CD38− cells, shows a similar pattern of proliferative response. This suggests thatex vivo expansion of transplantable human stem cells under this in vitro culture system is a general phenomenon and not just specific for CD34+ thy-1+ cells.

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Hematopoietic stem cells express Tie-2 receptor in the murine fetal liver

Blood ◽

10.1182/blood.v96.12.3757.h8003757_3757_3762 ◽

2000 ◽

Vol 96 (12) ◽

pp. 3757-3762 ◽

Cited By ~ 1

Author(s):

Hsiang-Chun Hsu ◽

Hideo Ema ◽

Mitsujiro Osawa ◽

Yukio Nakamura ◽

Toshio Suda ◽

...

Keyword(s):

Stem Cells ◽

Hematopoietic Stem Cells ◽

Receptor Tyrosine Kinase ◽

Fetal Liver ◽

Newborn Mice ◽

Hematopoietic Stem ◽

Fetal Liver Cells

Tie-2 receptor tyrosine kinase expressed in endothelial and hematopoietic cells is believed to play a role in both angiogenesis and hematopoiesis during development of the mouse embryo. This article addressed whether Tie-2 is expressed on fetal liver hematopoietic stem cells (HSCs) at day 14 of gestation. With the use of anti–Tie-2 monoclonal antibody, its expression was detected in approximately 7% of an HSC population of Kit-positive, Sca-1–positive, lineage-negative or -low, and AA4.1-positive (KSLA) cells. These Tie-2–positive KSLA (T+ KSLA) cells represent 0.01% to 0.02% of fetal liver cells. In vitro colony and in vivo competitive repopulation assays were performed for T+ KSLA cells and Tie-2–negative KSLA (T− KSLA) cells. In the presence of stem cell factor, interleukin-3, and erythropoietin, 80% of T+ KSLA cells formed colonies in vitro, compared with 40% of T− KSLA cells. Long-term multilineage repopulating cells were detected in T+ KSLA cells, but not in T− KSLA cells. An in vivo limiting dilution analysis revealed that at least 1 of 8 T+ KSLA cells were such repopulating cells. The successful secondary transplantation initiated with a limited number of T+ KSLA cells suggests that these cells have self-renewal potential. In addition, engraftment of T+ KSLA cells in conditioned newborn mice indicates that these HSCs can be adapted equally by the adult and newborn hematopoietic environments. The data suggest that T+ KSLA cells represent HSCs in the murine fetal liver.

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