Rapid discrimination of early CD34+ myeloid progenitors using CD45-RA analysis

Abstract Mononuclear cells (MNC) isolated by density centrifugation of cord blood and healthy bone marrow, and of peripheral blood (PB) from patients treated with granulocyte-macrophage colony-stimulating factor (GM-CSF) or G-CSF after chemotherapy, were double-stained with anti CD34 monoclonal antibody (MoAb) (8G12) versus anti CD45, CD45-RB, CD45- RO, and CD45-RA, respectively, and analyzed by flow cytometry. In all specimens, CD34+ MNC co-expressed CD45 at a low level and the expression of CD45-RB was similar or slightly higher. Most CD34+ MNC were negative for CD45-RO, a weak coexpression was only seen in some bone marrow (BM) and blood samples. In contrast, CD45-RA could subdivide the CD34+ population into fractions negative, dim (+), and normal positive (++) for these subgroups, and typical staining patterns were observed for the different sources of hematopoietic cells: in BM, most CD34+ MNC were RA++. In PB, their majority was RA++ after G-CSF but RA+ or RA- after GM-CSF. In cord blood, the hematopoietic progenitors were mainly RA-/RO-. Semisolid culture of sorted CD34+ MNC showed that clusters and dispersed (late) colony-forming unit-GM (CFU- GM) originated from 34+/RA++ cells, while the 34+/RA- MNC formed compact and multicentric, both white and red colonies derived from early progenitors. Addition of 20 ng stem cell factor per milliliter of medium containing 34+/RA- cord blood MNC led to a change of many burst- forming unit-erythrocyte (BFU-E) to CFU-mix which was not, at least to this extent, seen in blood and BM. We conclude that early myeloid CD34+ cells are 45+/RA-. Because this population excludes 34+/19+ B cells and 33+ myeloid cells, both of which are RA++, two-color flow cytometric analysis using CD34 and CD45-RA facilitates the characterization and quantification of early myeloid progenitor cells.

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Rapid discrimination of early CD34+ myeloid progenitors using CD45-RA analysis

Blood ◽

10.1182/blood.v81.9.2301.bloodjournal8192301 ◽

1993 ◽

Vol 81 (9) ◽

pp. 2301-2309 ◽

Cited By ~ 1

Author(s):

G Fritsch ◽

P Buchinger ◽

D Printz ◽

FM Fink ◽

G Mann ◽

...

Keyword(s):

Bone Marrow ◽

Cord Blood ◽

Mononuclear Cells ◽

Flow Cytometric Analysis ◽

Color Flow ◽

Gm Csf ◽

Cd34 Cells ◽

Myeloid Progenitor Cells ◽

Macrophage Colony ◽

Rapid Discrimination

Mononuclear cells (MNC) isolated by density centrifugation of cord blood and healthy bone marrow, and of peripheral blood (PB) from patients treated with granulocyte-macrophage colony-stimulating factor (GM-CSF) or G-CSF after chemotherapy, were double-stained with anti CD34 monoclonal antibody (MoAb) (8G12) versus anti CD45, CD45-RB, CD45- RO, and CD45-RA, respectively, and analyzed by flow cytometry. In all specimens, CD34+ MNC co-expressed CD45 at a low level and the expression of CD45-RB was similar or slightly higher. Most CD34+ MNC were negative for CD45-RO, a weak coexpression was only seen in some bone marrow (BM) and blood samples. In contrast, CD45-RA could subdivide the CD34+ population into fractions negative, dim (+), and normal positive (++) for these subgroups, and typical staining patterns were observed for the different sources of hematopoietic cells: in BM, most CD34+ MNC were RA++. In PB, their majority was RA++ after G-CSF but RA+ or RA- after GM-CSF. In cord blood, the hematopoietic progenitors were mainly RA-/RO-. Semisolid culture of sorted CD34+ MNC showed that clusters and dispersed (late) colony-forming unit-GM (CFU- GM) originated from 34+/RA++ cells, while the 34+/RA- MNC formed compact and multicentric, both white and red colonies derived from early progenitors. Addition of 20 ng stem cell factor per milliliter of medium containing 34+/RA- cord blood MNC led to a change of many burst- forming unit-erythrocyte (BFU-E) to CFU-mix which was not, at least to this extent, seen in blood and BM. We conclude that early myeloid CD34+ cells are 45+/RA-. Because this population excludes 34+/19+ B cells and 33+ myeloid cells, both of which are RA++, two-color flow cytometric analysis using CD34 and CD45-RA facilitates the characterization and quantification of early myeloid progenitor cells.

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Ineffective Hematopoiesis in Megaloblastic Anemia Is Associated with Higher Frequency of Apoptosis in Each Lineage Immature and Mature Cells.

Blood ◽

10.1182/blood.v106.11.3601.3601 ◽

2005 ◽

Vol 106 (11) ◽

pp. 3601-3601

Author(s):

Tatsuo Oyake ◽

Shigeki Ito ◽

Shugo Kowata ◽

Kazunori Murai ◽

Yoji Ishida

Keyword(s):

Bone Marrow ◽

Mononuclear Cells ◽

Bone Marrow Cells ◽

Megaloblastic Anemia ◽

Flow Cytometric Analysis ◽

Annexin V ◽

Cell Number ◽

Color Flow ◽

Cd34 Cells ◽

Normal Controls

Abstract A deficiency of Vitamin B12 is a major cause of megaloblastic anemia (MBA). Ineffective hematopoiesis is observed in MBA, characterized by cytopenia, bone marrow cells with dysplastic change and normal to hypercellularity. We reported that excessive apoptosis of each lineage CD34(+) cells was observed in myelodysplastic syndrome (MDS) in the last ASH meeting. In this study, we investigated the hypothesis that excessive apoptosis induced the ineffective hematopoiesis in MBA. We performed the three color flow cytometric analysis of bone marrow mononuclear cells in 12 MBA patients using PE labeled Annexin V, PerCP labeled anti-CD34 antibody and FITC labeled anti-each lineage antibody (anti-glycophorin A (GPA) antibody, anti-CD33 antibody and anti-CD41 antibody). The frequency of apoptosis in subpopulations of immature (CD34(+)) and each lineage (+) cells or those of mature (CD34(−)) and each lineage (+) cells were calculated as the ratio (%) of (cell number with Annexin V(+)) divided by (cell number in the subpopulation). The subpopulations include CD34(+)GPA(+) (immature erythroid), CD34(+)CD33(+) (immature myeloid), CD34(+)CD41(+) (immature megakaryocytic), CD34(−)GPA(+) (mature erythroid), CD34(−)CD33(+) (mature myeloid) and CD34(−)CD41(+) (mature megakaryocytic) cells. Much higher frequency of apoptosis was observed in each lineage CD34(+) cells in MBA (median: 23.8% (range: 10.8–43.6%) in erythroid, 43.5% (12.7–67.3%) in myeloid, 50.1% (21.0–64.1%) in megakaryocytic lineages, P< 0.05, respectively, n=12), compared to those in normal controls (8.5% (1.5–9.9%) in erythroid, 8.5% (2.2–8.8%) in myeloid, 7.7% (4.4–9.3%) in megakaryocytic lineages, respectively, n=10). While, the relatively higher frequency of apoptosis was observed in each lineage CD34(−) cells in MBA patients (median: 15.9% (range: 5.1–20.6%) in erythroid, 16.4% (5.6–23.2%) in myeloid, 16.1% (10.2–24.8%) in megakaryocytic lineages, P< 0.05, respectively, n=12), compared to those in normal controls (4.8% (1.3–6.6%) in erythroid, 2.2% (0.6–4.4%) in myeloid, 3.3% (1.5–7.1%) in megakaryocytic lineages, respectively, n=10). These results suggest that the excessive apoptosis occurs not only in CD34(+) but also in CD34(−) cells, which induces ineffective hematopoiesis in MBA. Figure 1. The frequency of apoptosis in CD34+ BM cells Figure 1. The frequency of apoptosis in CD34+ BM cells Figure 2. The frequency of apoptosis in CD34− BM cells Figure 2. The frequency of apoptosis in CD34− BM cells

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In Vitro Expansion of CD34+ Cells Mobilized with Chemotherapy and G-CSF

The International Journal of Artificial Organs ◽

10.1177/039139889301605s17 ◽

1993 ◽

Vol 16 (5_suppl) ◽

pp. 89-95 ◽

Cited By ~ 1

Author(s):

L. Teofili ◽

M.S. Iovino ◽

A. Di Mario ◽

E. Ortu La Barbera ◽

L. Pierelli ◽

...

Keyword(s):

Bone Marrow ◽

Mononuclear Cells ◽

Interleukin 1 ◽

Adherent Cell ◽

Colony Stimulating Factor ◽

Cell Recovery ◽

Gm Csf ◽

Cd34 Cells ◽

Macrophage Colony ◽

Stimulating Factor

Hemopoietic CD34+ progenitors were isolated by immunomagnetic method from normal bone marrow (BM) or from peripheral blood (PB) of patients with non-Hodgkin's lymphoma treated with chemotherapy and granulocyte colony-stimulating factor (GCSF). Aliquots were seeded in longterm cultures (LTC) on bone marrow-derived stromal layers; non-adherent and adherent clonogenic content of the cultures was assayed weekly. The final recovery and the clonogenic efficiency of the CD34+ cells were sligthly higher in PB samples than in BM controls. In long term cultures PB cells sustained hemopoiesis as much as BM cells; at week 3 and 4 PB total mononuclear cells and CD34+ cells showed a non-adherent cell recovery higher than the respective BM controls. Furthermore, PB CD34+ cells were expanded in liquid culture in the presence of granulocyte-macrophage colony-stimulating factor (GM-CSF) or G-CSF alone or combined with interleukin 3 (IL3), stem cell factor (SCF), interleukin 1 (IL 1), interleukin 6 (IL6). The combination of GM-CSF, IL3, SCF, IL 1 and IL6 produced the maximum increase of both mononuclear cells (30-fold) and granulocyte-macrophage colony forming units (CFU-GM) (4.6-fold) after 7 days of cultures; yet after 14 days a strong decrease of the CFU-GM occurred. These data suggest that G-CSF following chemotherapy mobilizes both early and committed hemopoietic progenitors.

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Hepatocyte Growth Factor Is Constitutively Produced by Human Bone Marrow Stromal Cells and Indirectly Promotes Hematopoiesis

Blood ◽

10.1182/blood.v89.5.1560.1560_1560_1565 ◽

1997 ◽

Vol 89 (5) ◽

pp. 1560-1565 ◽

Cited By ~ 2

Author(s):

Kenji Takai ◽

Junichi Hara ◽

Kunio Matsumoto ◽

Gaku Hosoi ◽

Yuko Osugi ◽

...

Keyword(s):

Bone Marrow ◽

Growth Factor ◽

Hepatocyte Growth Factor ◽

Stromal Cells ◽

Mononuclear Cells ◽

Gm Csf ◽

Tumor Growth Factor ◽

Cd34 Cells ◽

Factor Α ◽

Hepatocyte Growth

Bone marrow (BM) stromal cells are required for normal hematopoiesis. A number of soluble factors secreted by these cells that mediate hematopoiesis have been characterized. However, the mechanism of hematopoiesis cannot be explained solely by these known factors, and the existence of other, still unknown stromal factors has been postulated. We showed that hepatocyte growth factor (HGF ) is one such cytokine produced by human BM stromal cells. BM stromal cells were shown to constitutively produce HGF and also to express the c-MET/HGF receptor. The production of HGF was enhanced by addition of heparin and phorbol ester. Dexamethasone and tumor growth factor-β (TGF-β) inhibited the production of HGF. Interleukin-1α (IL-1α) tumor necrosis factor-α (TNF-α), and N6,2′-o-dibutyryl-adenosine-3′:5′-cyclic monophosphate (dbc-AMP) showed no obvious influence on HGF production. Western blot analysis of HGF derived from BM stromal cells showed two bands at 85 and 28 kD corresponding to native and variant HGF, respectively. Addition of recombinant HGF significantly promoted the formation of burst-forming unit-erythroid (BFU-E) and colony-forming unit-granulocyte erythroid macrophage (CFU-GEM) by BM mononuclear cells in the presence of erythropoietin and granulocyte-macrophage colony-stimulating factor (GM-CSF ), but the formation of CFU-GM was not modified. However, HGF had no effects on colony formation by purified CD34+ cells. Within BM mononuclear cells, c-MET was expressed on a proportion of cells (CD34−, CD33+, CD13+, CD14+, and CD15+), but was not found on CD34+ cells. We conclude that HGF is constitutively produced by BM stromal cells and that it enhances hematopoiesis. In addition, expression of c-MET on the stromal cells suggests the presence of an autocrine mechanism, operating through HGF, among stromal cells.

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The Human SHIP Gene Is Differentially Expressed in Cell Lineages of the Bone Marrow and Blood

Blood ◽

10.1182/blood.v89.6.1876 ◽

1997 ◽

Vol 89 (6) ◽

pp. 1876-1885 ◽

Cited By ~ 61

Author(s):

Susan J. Geier ◽

Paul A. Algate ◽

Kristen Carlberg ◽

Dave Flowers ◽

Cynthia Friedman ◽

...

Keyword(s):

Bone Marrow ◽

Mononuclear Cells ◽

Sh2 Domain ◽

Protein Species ◽

Peripheral Blood Mononuclear ◽

Phosphorylated Proteins ◽

Cd34 Cells ◽

Negative Effect ◽

Mrna And Protein Expression ◽

Macrophage Colony

Abstract The macrophage colony-stimulating factor receptor and several other hematopoietic growth factor receptors induce the tyrosine phosphorylation of a 145- to 150-kD protein in murine cells. We have previously cloned a cDNA for the murine 150-kD protein, SHIP, and found that it encodes a unique signaling intermediate that binds the SHC PTB domain through at least one tyrosine phosphorylated (NPXY) site in the carboxyl-terminal region. SHIP also contains several potential SH3 domain-binding sites, an SH2 domain for binding other tyrosine phosphorylated proteins, and an enzymatic activity that removes the phosphate from the 5 position of phosphatidylinositol 3,4,5-phosphate or from inositol 1,3,4,5-phosphate. SHIP has a negative effect on cell growth and therefore loss or modification may have profound effects on hematopoietic cell development. In this study, we have cloned a cDNA for human SHIP and examined mRNA and protein expression of SHIP and related species in bone marrow and blood cells. Flow cytometry indicates that at least 74% of immature CD34+ cells express SHIP cross-reacting protein species, whereas within the more mature population of CD33+ cells, only 10% of cells have similar expression. The majority of T cells react positively with the anti-SHIP antibodies, but significantly fewer B cells are positive. Immunoblotting detects up to seven different cross-reacting SHIP species, with peripheral blood mononuclear cells exhibiting primarily a 100-kD protein and a CD34+ acute myeloblastic leukemia expressing mainly 130-kD and 145-kD forms of SHIP. Overall, these results indicate that there is an enormous diversity in the size of SHIP or SHIP-related mRNA and protein species. Furthermore, the expression of these protein species changes according to both the developmental stage and differentiated lineage of the mature blood cell.

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Stimulation of nonclonal hematopoiesis and suppression of the neoplastic clone after treatment with recombinant human granulocyte- macrophage colony-stimulating factor in a patient with therapy-related myelodysplastic syndrome

Blood ◽

10.1182/blood.v74.5.1491.1491 ◽

1989 ◽

Vol 74 (5) ◽

pp. 1491-1498 ◽

Cited By ~ 50

Author(s):

S Vadhan-Raj ◽

HE Broxmeyer ◽

G Spitzer ◽

A LeMaistre ◽

S Hultman ◽

...

Keyword(s):

Bone Marrow ◽

Mononuclear Cells ◽

Fragment Length Polymorphism ◽

Marrow Cell ◽

Colony Stimulating Factor ◽

Gm Csf ◽

Selective Growth Advantage ◽

Macrophage Colony Stimulating Factor ◽

Macrophage Colony ◽

Stimulating Factor

Abstract A complete hematologic remission was achieved in a patient with therapy- related preleukemia and transfusion-dependent pancytopenia after treatment with recombinant human granulocyte-macrophage colony- stimulating factor (GM-CSF). The patient remained in remission for nearly 1 year despite the discontinuation of GM-CSF treatment. Several lines of evidence suggest that normal hematopoiesis was restored after GM-CSF treatment. First, the cytogenetic anomaly, which was present before GM-CSF, completely disappeared after three cycles of treatment. Cytogenetic conversion was documented by conventional karyotypic evaluation of mitotic bone marrow cell preparations as well as by premature chromosome condensation analysis of the nonmitotic cells of bone marrow and peripheral blood. Second, the growth pattern and cycle status of bone marrow granulocyte-macrophage (CFU-GM) and erythroid (BFU-E) progenitor cells were found to be normal during remission. Third, X chromosome-linked restriction fragment length polymorphism- methylation analysis of DNA from mononuclear cells (greater than 80% lymphocytes) and mature myeloid elements showed a polyclonal pattern. These findings suggest that restoration of hematopoiesis in this patient after GM-CSF treatment may have resulted from suppression of the abnormal clone and a selective growth advantage of normal elements.

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Action of interleukin-3, G-CSF, and GM-CSF on highly enriched human hematopoietic progenitor cells: synergistic interaction of GM-CSF plus G-CSF

Blood ◽

10.1182/blood.v74.1.110.110 ◽

1989 ◽

Vol 74 (1) ◽

pp. 110-114 ◽

Cited By ~ 50

Author(s):

I McNiece ◽

R Andrews ◽

M Stewart ◽

S Clark ◽

T Boone ◽

...

Keyword(s):

Bone Marrow ◽

Progenitor Cells ◽

Colony Formation ◽

Synergistic Interaction ◽

Interleukin 3 ◽

Gm Csf ◽

Cd34 Cells ◽

Normal Human ◽

Macrophage Colony Stimulating Factor ◽

Macrophage Colony

Abstract Purified preparations of recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF), granulocyte CSF (G-CSF), and interleukin 3 (IL-3 or multi-CSF) alone and in combination, have been compared for their stimulatory effects on human granulocyte-macrophage colony forming cells (GM-CFC). In cultures of unseparated normal human bone marrow, the combinations of G-CSF plus IL-3 and GM-CSF plus IL-3 stimulated additive numbers of GM colonies, while GM-CSF plus G-CSF stimulated greater than additive numbers of GM colonies, compared with the sum of the colony formation obtained with each factor alone. Cultures of unseparated bone marrow, harvested from patients four to six days after administration of 5-fluorouracil (5-FU), resulted in additive GM colony formation with GM-CSF plus G-CSF, GM-CSF plus IL-3, and G-CSF plus IL-3. In order to address the possibility of secondary factor involvement in the synergistic interaction of GM-CSF and G-CSF, CD33+/CD34+ colony forming cells were separated from normal and post FU marrow by two color fluorescence activated cell sorting. In cultures of CD33+/CD34+ cells the combination of GM-CSF plus G-CSF stimulated a synergistic increase in GM colonies while GM-CSF plus IL-3 stimulated additive numbers of colonies. These results suggest that GM-CSF, G-CSF, and IL-3 stimulate distinct populations of GM-CFC. Furthermore GM-CSF and G-CSF interact synergistically and this action is a direct effect on progenitor cells not stimulated by GM-CSF or G-CSF alone.

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Engraftment of Human Mesenchymal Stem Cells upon Transplantation into Newborn Rag2−/−gc−/− Mice.

Blood ◽

10.1182/blood.v108.11.1652.1652 ◽

2006 ◽

Vol 108 (11) ◽

pp. 1652-1652

Author(s):

Patrick Ziegler ◽

Steffen Boettcher ◽

Hildegard Keppeler ◽

Bettina Kirchner ◽

Markus G. Manz

Keyword(s):

Stem Cells ◽

Bone Marrow ◽

Cord Blood ◽

Human Mesenchymal Stem Cells ◽

Rt Pcr ◽

Hematopoietic Stem ◽

Gm Csf ◽

Cd34 Cells ◽

Gene Transcripts

Abstract We recently demonstrated human T cell, B cell, dendritic cell, and natural interferon producing cell development and consecutive formation of primary and secondary lymphoid organs in Rag2−/−gc−/− mice, transplanted as newborns intra-hepatically (i.h.) with human CD34+ cord blood cells (Traggiai et al., Science 2004). Although these mice support high levels of human cell engraftment and continuous T and B cell formation as well as CD34+ cell maintenance in bone marrow over at least six month, the frequency of secondary recipient reconstituting human hematopoietic stem and progenitor cells within the CD34+ pool declines over time. Also, although some human immune responses are detectable upon vaccination with tetanus toxoid, or infection with human lymphotropic viruses such as EBV and HIV, these responses are somewhat weak compared to primary human responses, and are inconsistent in frequency. Thus, some factors sustaining human hematopoietic stem cells in bone marrow and immune responses in lymphoid tissues are either missing in the mouse environment, or are not cross-reactive on human cells. Human mesenchymal stem cells (MSCs) replicate as undifferentiated cells and are capable to differentiate to multiple mesenchymal tissues such as bone, cartilage, fat, muscle, tendon, as well as marrow and lymphoid organ stroma cells, at least in vitro (e.g. Pittenger et al., Science 1999). Moreover, it was shown that MSCs maintain CD34+ cells to some extend in vitro, and engraft at low frequency upon transplantation into adult immunodeficient mice or fetal sheep as detected by gene transcripts. We thus postulated that co-transplantation of cord blood CD34+ cells and MSCs into newborn mice might lead to engraftment of both cell types, and to provision of factors supporting CD34+ maintenance and immune system function. MSCs were isolated and expanded by plastic adherence in IMDM, supplemented with FCS and cortisone (first 3 weeks) from adult bone marrow, cord blood, and umbilical vein. To test their potential to support hemato-lymphopoiesis, MSCs were analyzed for human hemato-lymphotropic cytokine transcription and production by RT-PCR and ELISA, respectively. MSCs from all sources expressed gene-transcripts for IL-6, IL-7, IL-11, IL-15, SCF, TPO, FLT3L, M-CSF, GM-CSF, LIF, and SDF-1. Consistently, respective cytokines were detected in supernatants at the following, declining levels (pg/ml): IL-6 (10000-10E6) > SDF-1 > IL-11 > M-CSF > IL-7 > LIF > SCF > GM-CSF (0–450), while FLT3L and TPO were not detectable by ELISA. Upon i.h. transplantation of same passage MSCs (1X10E6) into sublethally irradiated (2x2 Gy) newborn Rag2−/−gc−/− mice, 2-week engraftment was demonstrated by species specific b2m-RT-PCR in thymus, spleen, lung, liver and heart in n=7 and additionally in thymus in n=3 out of 13 animals analyzed. Equally, GFP-RNA transcripts were detectable in the thymus for up to 6 weeks, the longest time followed, upon co-transplantation of same source CD34+ cells and retrovirally GFP-transduced MSCs in n=2 out of 4 animals. Further engraftment analysis of ongoing experiments will be presented. Overall, these results demonstrate that human MSC produce hemato-lymphoid cytokines and engraft in newborn transplanted Rag2−/−gc−/− mice, at least at early time-points analyzed. This model thus might allow studying hematopoietic cell and MSC-derived cell interaction, and might serve as a testing system for MSC delivered gene therapy in vivo.

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Vitamin K2 Supports Hematopoiesis through Acting on Bone Marrow Mesenchymal Stromal/Stem Cells

Blood ◽

10.1182/blood.v126.23.1192.1192 ◽

2015 ◽

Vol 126 (23) ◽

pp. 1192-1192 ◽

Cited By ~ 2

Author(s):

Aya Fujishiro ◽

Yasuo Miura ◽

Masaki Iwasa ◽

Sumie Fujii ◽

Akihiro Tamura ◽

...

Keyword(s):

Stem Cells ◽

Bone Marrow ◽

Flow Cytometric Analysis ◽

Hematopoietic Cells ◽

Vitamin K2 ◽

Therapeutic Effects ◽

Dependent Manner ◽

Hematopoietic Stem ◽

Gm Csf ◽

Cd34 Cells

Abstract [Background] Myelodysplastic syndrome is an intractable disorder characterized by ineffective hematopoiesis. Although allogeneic hematopoietic stem cell transplantation is the only curative therapy for eligible patients, hematopoiesis-supportive pharmacotherapy is practically important for transplant-ineligible patients to overcome transfusion dependency and infections. Vitamin K2 (VK2, menatetrenone) is a drug used to aim at improvement of hematopoiesis in MDS patients (Leukemia 14: 1156, 2000). However, the exact mechanism how VK2 improves hematopoiesis remains largely unknown. It was reported that VK2 induces MDS cells to undergo apoptosis (Leukemia 13: 1399, 1999). Here, we investigated our hypothesis that VK2 exerts its hematopoiesis-supportive effects through acting on mesenchymal stem/stromal cells (BM-MSCs) in the bone marrow microenvironment. [Methods] Normal bone marrow (BM) samples from healthy adult volunteers were purchased from AllCells (Emeryville, CA). BM-CD34+ cells were isolated from BM-mononuclear cells using anti-CD34 immunomagnetic microbeads (Miltenyi Biotec, Bergisch Gladbach, Germany). Human BM-MSCs were isolated according to our previously published methods (Stem Cells 32:2245, 2014). In co-culture experiments, BM-MSCs with or without VK2 treatment were seeded on a 24-well culture plate. BM-CD34+ cells were applied on the MSC-grown plate and co-cultured in SFEM (StemCell Technologies, Vancouver, Canada) supplemented with 100 ng/mL SCF, 100 ng/mL Flt-3 ligand, 50 ng/mL TPO and 20 ng/mL IL-3. After 10 days of co-culture, the number and surface marker expression of the expanded hematopoietic cells were examined by flow cytometric analysis. [Results] We first tested the direct effect of VK2 on BM-CD34+ cells. BM-CD34+ cells were treated with VK2 at various concentrations ranged from 0 µM to 10 µM for 24 hours and then cultured in SFEM in combinations with cytokines. Surprisingly, viable hematopoietic cells were hardly detected in the expansion culture of BM-CD34+ cells treated with 10 µM VK2. Even with 1 µM treatment, the number of CD45+ cells was decreased, as compared to that of expansion culture of untreated BM-CD34+ cells. The apoptosis analysis showed that the percentage of AnnexinV+ PI+ cells in the expanded hematopoietic cells is increased by VK2 treatment. We next examined the effect of VK2 on the hematopoiesis-supportive capability of BM-MSCs. BM-MSCs were pretreated with VK2 at various concentrations and then co-cultured with BM-CD34+ cells. The numbers of CD34+ cells and CD45+ cells were increased in a VK2 dose-dependent manner. These results demonstrated that VK2 shows different effects on distinct stem/progenitor cells: the induction of apoptosis in BM-CD34+ cells and the enhancement of hematopoiesis-supportive capability of BM-MSCs. We then investigated whether apoptosis-related cell death of BM-CD34+ cells by VK2 treatment is ameliorated in the presence of BM-MSCs. Both BM-CD34+ cells and BM-MSCs were treated with VK2 for 24 hours, and then co-cultured. The number of CD34+ cells was not decreased significantly in contrast to its severe decrease in single culture of VK2-treated BM-CD34+ cells. We further analyzed the effect of VK2 on BM-MSCs. Subpopulation analysis in co-culture of CD34+ cells with VK2-treated BM-MSCs showed that the expansion efficacy of CD34+CD38+ cells is higher in comparison to that of CD34+CD38- cells. In addition, the percentages of CD34-CD33+ cells and CD34-CD13+ cells were higher than those in co-cultures with untreated BM-MSCs. Therefore, VK2-treated BM-MSCs supported the expanded CD34+ cells to skew their phenotype toward myeloid lineage. The presence of a transwell in the co-culture system was unrelated to the expansion pattern of CD34+ cells, which suggested the involvement of soluble factors with respect to the underlining mechanism. We therefore compared the levels of hematopoiesis-supporting cytokine mRNA expression in VK2-treated and untreated BM-MSCs: VK2-treated BM-MSCs showed lower expression of CXCL12/SDF-1 mRNA and a trend toward higher expression of GM-CSF mRNA. [Summary] VK2 acted on BM-MSCs to support their ability to enhance expansion and myeloid differentiation of BM-CD34+ cells probably via altered GM-CSF and CXCL12/SDF-1 expression in MSCs. These findings may help to identify the mechanisms of therapeutic effects of VK2 in patients with MDS (Figure). Disclosures No relevant conflicts of interest to declare.

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Surface fucosylation of human cord blood cells augments binding to P-selectin and E-selectin and enhances engraftment in bone marrow

Blood ◽

10.1182/blood-2004-02-0650 ◽

2004 ◽

Vol 104 (10) ◽

pp. 3091-3096 ◽

Cited By ~ 146

Author(s):

Lijun Xia ◽

J. Michael McDaniel ◽

Tadayuki Yago ◽

Andrea Doeden ◽

Rodger P. McEver

Keyword(s):

Bone Marrow ◽

Cord Blood ◽

Mononuclear Cells ◽

Scid Mice ◽

Sialyl Lewis X ◽

Human Umbilical Cord Blood ◽

Human Umbilical Cord ◽

Hematopoietic Stem ◽

Similar Treatment ◽

Cd34 Cells

Abstract Murine hematopoietic stem and progenitor cells (HSPCs) home to bone marrow in part by rolling on P-selectin and E-selectin expressed on endothelial cells. Human adult CD34+ cells, which are enriched in HSPCs, roll on endothelial selectins in bone marrow vessels of nonobese diabetic/severe combined immune deficiency (NOD/SCID) mice. Many human umbilical cord blood (CB) CD34+ cells do not roll in these vessels, in part because of an uncharacterized defect in binding to P-selectin. Selectin ligands must be α1-3 fucosylated to form glycan determinants such as sialyl Lewis x (sLex). We found that inadequate α1-3 fucosylation of CB CD34+ cells, particularly CD34+CD38–/low cells that are highly enriched in HSPCs, caused them to bind poorly to E-selectin as well as to P-selectin. Treatment of CB CD34+ cells with guanosine diphosphate (GDP) fucose and exogenous α1-3 fucosyltransferase VI increased cell-surface sLex determinants, augmented binding to fluid-phase P- and E-selectin, and improved cell rolling on P- and E-selectin under flow. Similar treatment of CB mononuclear cells enhanced engraftment of human hematopoietic cells in bone marrows of irradiated NOD/SCID mice. These observations suggest that α1-3 fucosylation of CB cells might be a simple and effective method to improve hematopoietic cell homing to and engraftment in bone marrows of patients receiving CB transplants.

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