Clinical evidence of hematopoietic restoration with umbilical cord blood (UCB) grafts indicates the UCB can be a useful source of hematopoietic stem cells for routine bone marrow reconstitution. Considering (10 +/- 5) x 10(8) nucleared cells per cord blood unit, there is a potential limitation for the use of cord blood in adults, which, however, can be overcome by ex vivo expansion of cells. A prerequisite for expansion is the significantly higher recovery of MNC, CD34+ cells and colony-forming cells (CFC) by thawing cryopreserved MNC. Cooling rate always acts as a critical factor that can affect the recovery of cells. Although the rate of - 1 degrees C/min is adopted in most of the cryopreservations, no data has been reported about the detailed effects of different cooling rates. The aim of the study was to reveal the different effects of cooling rates on cryopreservation of hematopoietic stem cells from cord blood. UCB samples were collected, and cryopreserved as mononuclear cells (MNC) with different cooling rates of - 0.5 degrees C/min, - 1 degrees C/min, - 5 degrees C/min, and the recovery and viability of MNC and CD34+ cells, the clonogenic capacity and the ex vivo expansion potential of UCB progenitor cells were evaluated after thawing. With - 1 degrees C/min cooling rate, the recovery of MNC reached 93.3% +/- 1.8% , viability 95.0% +/- 3.9% , recovery of CD34+ cells 80.0% +/- 17.9% , and clonogenic recovery were 87.1% +/- 5.5%, 88.5% +/- 8.9%, 86.2% +/- 7.4% for BFU-E CFU-GM CFU-MK, respectively. After 14 days of liquid culture, no significant difference was detected in CFC expansion between fresh and cryopreserved MNC cells with - 1 degrees C/min cooling rate, but this was not the case with - 0.5 degreesC/min and - 5 degrees C/min. In conclusion, it was demonstrated that controlling the rate at - 1 degrees C/min is more suitable for cryopreservation of hematopoietic stem cells than - 0.5 degrees C/min and - 5 degrees C/min.
Cell Survival ; physiology ; Cells, Cultured ; Cryopreservation ; methods ; Erythroid Precursor Cells ; cytology ; Fetal Blood ; cytology ; Flow Cytometry ; Granulocyte-Macrophage Progenitor Cells ; cytology ; Hematopoietic Stem Cells ; cytology ; Humans

OBJECTIVETo explore the influence of 1,4-benzoquinone (1,4-BQ) on proliferation of human bone marrow haematopoietic stem cells (hBM-HSCs) and human bone marrow mesenchymal stem cells (hBM-MSCs).

METHODSThe bone marrow samples were collected from a healthy donor. Methylcellulose semi-solid culture medium was used to culture the mononuclear cells of bone marrow in different culture systems. Colony-forming unit (CFU) assay was utilized to evaluate the proliferation of hBM-HSCs exposed to 1,4-BQ at the doses of 10, 25, 50 and 100 µmol/L and to observe the influence of 1,4-BQ on the Colony-forming unit-erythroid (CFU-E)/Burst-forming unit-erythroid (BFU-E), Colony-forming unit-granulocyte, macrophage (CFU-GM), Colony-forming unit-granulocyte, erythroid, macrophage, megakaryocyte (CFU-GEMM) in hBM-MSCs. MTT assay was used to detect the proliferation of hBM-MSCs exposed to 1,4-BQ at the doses of 1, 5, 10, 25, 50, 100, 200, 500 and 1000 µmol/L for 24 h, respectively, after hBM-MSCs were isolated, cultured and expanded.

RESULTSThe results of CFU assay indicated that numbers of CFU-E/BFU-E, CFU-GM and CFU-GEMM in 25, 50 and 100 µmol/L groups significantly decreased, as compared with control group (P < 0.05). However, no significant difference was found between the 10 µmol/L group and the control group. The results of MTT assay showed that the cellular viability of hBM-MSCs exposed to 1,4-BQ at the doses of 50 ∼ 200 µmol/L for 24 h significantly decreased in a dose-depended manner. When the exposure dose was higher than 200 µmol/L, the cellular viability of hBM-MSCs was lower than 5% which was significantly lower than that of control group (P < 0.05). When the exposure dose was lower than 25 µmol/L, there was no significant difference of cellular viability between exposure group and control group (P > 0.05).

CONCLUSIONThe results of the present study demonstrated that 1,4-BQ could inhibit the colony forming of hBM-HSCs and the relative viability of hBM-MSCs in vitro. The hematotoxicity induced by 1,4-BQ may be related to inhibiting the proliferation capacity of hBM-HSCs.

Benzoquinones ; toxicity ; Bone Marrow Cells ; cytology ; Cell Proliferation ; drug effects ; Cells, Cultured ; Erythroid Precursor Cells ; Granulocyte-Macrophage Progenitor Cells ; cytology ; Humans ; Mesenchymal Stromal Cells ; cytology

The effects of the Smad3- knockout on the hematopoiesis of mouse were investigated in this work. Five pairs of wild type and Smad3- null mice were studied. White blood cell(WBC), red blood cell(RBC) and platelet (PLT) counting of peripheral blood cells were performed with blood obtained from tails. And white blood cells were classified by their morphology. Bone marrow nucleated cells (BMNCs) were counted and classified. The CFU-GM, BFU-E, CFU-GEMM yields were measured in each pair of mice. CFU-S yield of each mouse was measured by injecting bone marrow cells into lethally irradiated 8-10 weeks old wild type female mice. And the pathomorphism of their bone marrows, spleens and livers were observed. As a result, WBC and PLT of Smad3- null mice were significantly higher than those in wild type mice. Smad3- null mice had much more proportion of granulocytes in classification. There wasn't any difference in RBC counting and BFU-E measurement. The yield of CFU-GM increased, while the yields of CFU-GEMM and CFU-S markedly reduced. Bone marrows are actively proliferative, with granulocytosis. The granulocyte/erythrocyte ratio increased. There were no obviously alterative in spleen and liver. Thus Smad3- knockout results in a decreased number of stem and progenitor cells. Moreover hematopoietic differentiation is abnormal with a tendency to forming more granulocytes and platelets. The effect of Smad3 on hematopoiesis is correlative to that of TGF-beta.
Animals ; Bone Marrow Cells ; cytology ; metabolism ; Cell Differentiation ; Erythrocytes ; cytology ; metabolism ; Erythroid Precursor Cells ; cytology ; metabolism ; Female ; Granulocyte-Macrophage Progenitor Cells ; cytology ; metabolism ; Granulocytes ; cytology ; metabolism ; Hematopoiesis ; genetics ; Mice ; Mice, Knockout ; Myeloid Progenitor Cells ; cytology ; metabolism ; Smad3 Protein ; genetics

The chronic myelogenous leukemic K562 cell line carrying Bcr-Abl tyrosine kinase is considered as pluripotent hematopoietic progenitor cells expressing markers for erythroid, granulocytic, monocytic, and megakaryocytic lineages. Here we investigated the signaling modulations required for induction of erythroid differentiation of K562 cells. When the K562 cells were treated with herbimycin A (an inhibitor of protein tyrosine kinase), ras antisense oligonucleotide, and PD98059 (a specific inhibitor of MEK), inhibition of ERK/MAPK activity and cell growth, and induction of erythroid differentiation were observed. The ras mutant, pZIPRas61leu-transfected cells, K562-Ras61leu, have shown a markedly decreased cell proliferation rate with approximately 2-fold doubling time, compared with the parental K562 cells, and about 60% of these cells have shown the phenotype of erythroid differentiation. In addition, herbimycin A inhibited the growth rate and increased the erythroid differentiation, but did not affect the elevated activity of ERK/MAPK in the K562-Ras61leu cells. On the other hand, effects of PD98059 on the growth and differentiation of K562-Ras61leu cells were biphasic. At low concentration of PD98059, which inhibited the elevated activity of ERK/MAPK to the level of parental cells, the growth rate increased and the erythroid differentiation decreased slightly, and at high concentration of PD98059, which inhibited the elevated activity of ERK/MAPK below that of the parental cells, the growth rate turned down and the erythroid differentiation was restored to the untreated control level. Taken together, these results suggest that an appropriate activity of ERK/MAPK is required to maintain the rapid growth and transformed phenotype of K562 cells.
Androstadienes/pharmacology ; Ca(2+)-Calmodulin Dependent Protein Kinase ; Cell Differentiation/drug effects ; Enzyme Inhibitors/pharmacology ; Erythroid Progenitor Cells/physiology* ; Erythroid Progenitor Cells/cytology ; Erythropoiesis* ; Flavones/pharmacology ; Human ; K562 Cells ; Leukemia, Myeloid/pathology ; Oligonucleotides, Antisense/pharmacology ; Quinones/pharmacology ; ras Proteins/metabolism*

Stirred culture offers a number of advantages over static systems as it maintains a stable, homogeneous culture environment and is easy to scale-up. This paper focused on the development and application of stirred tank bioreactor to culture hematopoietic cells. Preliminary study of stirred culture of hematopoietic cells was carried out in cord blood mononuclear cells culture in spinner flask. The results showed that the amplification rates of total cell, CFU-GM and BFU-E, with the exception of CFU-Mk, were greater in spinner flask than T-flask. The number of total cells increased 20 fold after 14 days incubation in spinner flask. The amplification rates of CFU-GM, CFU-Mk and BFU-E reached maximum at 10th day, 10th day and 7th day respectively, and the maximal amplification rates were 9.2-fold, 5.5-fold and 2.4-fold respectively, whereas the rate of CD34+ cells in spinner flask was (6.7 +/- 4.0)-fold at day 10. These results indicated that the stirred culture system is better than the static culture systems for hematopoietic cell proliferation. The biocompatibility of cord blood MNC to different types of materials used in bioreactors was also tested. The results showed that glass, stainless steel 316L and polytetraflouroethylene (PTFE) supported the growth of hematopoietic cells well. A higher cell density was reached in stirred bioreactors with controlled pH and DO than static culture. These findings suggested that the controlled large-scale culture could be used to overcome the clinical shortage of hematopoietic cells.
Antigens, CD34 ; metabolism ; Bioreactors ; Cell Culture Techniques ; instrumentation ; methods ; Erythroid Precursor Cells ; cytology ; Fetal Blood ; cytology ; Granulocyte-Macrophage Progenitor Cells ; cytology ; Humans ; Polytetrafluoroethylene ; Stainless Steel

The purpose of this study was to explore the differences in megakaryocyte progenitor ex vivo expansion between CD34+ cells derived from human umbilical cord blood (CB) and bone marrow (BM). Mononuclear cells (MNCs) were obtained from CB or BM by Ficoll-Hypaque density gradient separation. CD34+ cells were purified by magnetic cell sorting (MACS). The selected CD34+ cells were seeded in serum-free conditions stimulated with thrombopoietin (TPO), TPO+interleukin 11 (IL-11), or TPO+IL11+heparin for 14 days. Amplification product (CD34+, CD41a+, and CD34+ CD41a+ cells) immunophenotypes, megakaryocyte apoptosis rates and the DNA content were measured by fluorescence-activated cell sorting (FACS). The colony-forming units of granulocytes and monocytes (CFU-GM), burst-forming units of erythrocytes (BFU-E), and colony-forming units of megakaryocytes (CFU-Mk) were also evaluated by the colony-forming units (CFU) assay. The results indicated that CD34+ cells derived from CB showed higher expansion ability of total cell counts, CD41a+ and CD34+ CD41a+ cells than those derived from BM for all days 14 of culture (p<0.05, respectively). There were no significant differences in CFU-GM, BFU-E, and total CFU-Mk counts between CB and BM-derived CD34+ cells on day 0 (p>0.05, respectively), but CB-derived CFU-Mk seemed mainly large colonies, and the number of large colonies was higher than that from BM (p<0.05) on day 0. There were no significant differences in expansion ability of CFU-GM between CB and BM-derived cells on days 7, 10, and 14 of culture (p > 0.05, respectively), but the expansion ability of BFU-E and CFU-Mk derived from CB cells was higher than that from BM (p<0.05, respectively). There were no significant differences in apoptosis rates of megakaryocyte from two source cells for days 14 of culture. Megakaryocytes derived from CB mostly showed the 2N DNA content (>90%) for days 14 of culture, while those cells derived from BM showed the increased DNA content, and 4N, 8N or more ploidy cells gradually increased with prolonging of culture time. It is concluded that CB-derived CD34+ cells have a greater proliferation potential than that derived from BM, which is therefore proven to be a better cell source for megakaryocyte progenitor expansion in vitro.
Antigens, CD34 ; Bone Marrow Cells ; cytology ; immunology ; Cell Culture Techniques ; methods ; Cell Differentiation ; Cell Division ; Cell Separation ; Cells, Cultured ; Erythroid Precursor Cells ; cytology ; Fetal Blood ; cytology ; immunology ; Humans ; Megakaryocyte Progenitor Cells ; cytology ; immunology

OBJECTIVETo investigate the effects of oxygen concentration and reactive oxygen species (ROS) on the biological characteristics of hematopoietic stem cells (HSC) and to analyzed the relationship among the oxygen concentration, ROS and the biological characteristics of mouse HSC through simulation of oxygen environment experienced by PB HSC during transplantation.

METHODSThe detection of reactive oxygen species (ROS), in vitro amplification, directional differentiation (BFU-E, CFU-GM, CFU-Mix), homing of adhesion molecules (CXCR4, CD44, VLA4, VLA5, P-selectin), migration rate, CFU-S of NOD/SCID mice irradiated with sublethal dose were performed to study the effect of oxgen concentration and reactive oxygen species on the biological characteristics of mouse BM-HSC and the relationship among them.

RESULTSThe oxygen concentrations lower than normal oxygen concentration (especially hypoxic oxygen environment) could reduce ROS level and amplify more Lin(-) c-kit(+) Sca-1(+) BM HSC, which was more helpful to the growth of various colonies (BFU-E, CFU-GM, CFU-Mix) and to maintain the migratory ability of HSC, thus promoting CFU-S growth significantly after the transplantation of HSC in NOD/SCID mice irradiated by a sublethal dose. BM HSC exposed to oxygen environments of normal, inconstant oxygen level and strenuously thanging of oxygen concentration could result in higher level of ROS, at the same time, the above-mentioned features and functional indicators were relatively lower.

CONCLUSIONThe ROS levels of BM HSC in PB HSCT are closely related to the concentrations and stability of oxygen surrounding the cells. High oxygen concentration results in an high level of ROS, which is not helpful to maintain the biological characteristics of BM HSC. Before transplantation and in vitro amplification, the application of antioxidancs and constant oxygen level environments may be beneficial for transplantation of BMMSC.

Animals ; Cell Differentiation ; Culture Media ; chemistry ; Erythroid Precursor Cells ; cytology ; Granulocyte-Macrophage Progenitor Cells ; cytology ; Hematopoietic Stem Cells ; cytology ; metabolism ; Mice ; Mice, Inbred NOD ; Mice, SCID ; Oxygen ; chemistry ; Reactive Oxygen Species ; metabolism

OBJECTIVEThe previous studies indicated that mesenchymal stem cells (MSCs) either from umbilical cord blood (UCB) or from bone marrow (BM) had the same biological characteristics and the function of secreting hematopoietic growth factors (HGFs). The present study aimed to understand the effects of human UCB MSCs on the expansion of CD(34)(+) cells from UCB.

METHODS1. Human UCB CD(34)(+) cells were incubated in the system containing UCB MSCs, HGFs and serum free medium. 2. The surface markers (CD(34)(+), CD(34)(+)CD(38)(-), CD(34)(+)CD(3)(+), CD(34)(+)CD(19)(+), CD(34)(+)CD(33)(+), CD(34)(+)CD(41a)(+)) on expanded UCB cells were examined by flow cytometry on the 6th and 12th days. 3. The expanded and unexpanded cells were cultured in semi-solid culturing system and checked for colony forming units of granulocyte and macrophage (CFU-GM), erythroid burst-forming unit (BFU-E), colony forming units of granulocyte- erythrocyte-megakaryocyte-macrophage (CFU-Mix) and colony forming units of high-proliferative potential (CFU-HPP).

RESULTS1. The expansion folds of CD(34)(+)CD(38)(-) cells from UCB MSCs + HGFs groups on the 6th and 12th days were 159.43 and 436.68, respectively. Interestingly, the percentage of CD(34)(+)CD(38)(-) cells declined in HGFs group after expanding for 12 days, but it rose to 9.98% in the UCB MSCs + HGFs group. 2. Colony forming capacity of expanded UCB cells showed that the folds of CFU-Mix and CFU-HPP of UCB MSCs + HGFs group increased from day 6 to day 12, but the folds decreased in the HGFs group. 3. From day 0 to day 12, CD(34)(+)CD(33)(+) cells and CD(34)(+)CD(41a)(+) cells were amplified gradually, but CD(34)(+)CD(19)(+) and CD(34)(+)CD(3)(+) cells decreased gradually, and in UCB MSCs + HGFs group this phenomenon was more significant than that in HGFs group.

CONCLUSION1. UCB MSCs containing system not only has the ability to expand the primitive HSCs but also has the ability to sustain the proliferation of HSCs. 2. UCB MSCs containing system amplified mainly myeloid and megakaryocytoid progenitor subsets. These may have clinical significance in reducing infection and hemorrhage.

Antigens, CD34 ; biosynthesis ; metabolism ; Cell Culture Techniques ; Cell Differentiation ; Cell Proliferation ; Culture Media, Conditioned ; Culture Media, Serum-Free ; Erythroid Precursor Cells ; Fetal Blood ; cytology ; Flow Cytometry ; Granulocyte-Macrophage Progenitor Cells ; Hematopoietic Cell Growth Factors ; pharmacology ; Hematopoietic Stem Cells ; metabolism ; Humans ; Infant, Newborn ; Mesenchymal Stromal Cells ; immunology ; metabolism