Distribution and Characteristics of CD133+, CD34+ Cells in Counterflow Centrifugal Elutriation Fraction of Cord Blood and Bone Marrow / 대한소아혈액종양학회지

PURPOSE: Many studies for hematopoietic stem cell have investigated CD133, instead of CD34, as a new surrogate stem cell marker. Counterflow centrifugal elutriation (CCE) is a physical separation of a homogeneous cell population through cell sedimentation characteristics. We evaluated the stem cell distribution and hematopoietic function from cord blood (CB) and bone marrow (BM) through CCE. METHODS: We obtained total nucleated cells from CB and BM, and separated the cell fractions according to media infusion flow rates (17 mL/min (FR 17), 24 mL/min (FR 24), 29 mL/min (FR 29), and rotor off (R/O) ) by CCE. We analyzed the proportion of CD34+ and CD133+ cells in each fraction, and performed methylcellulose-based colony assay. RESULTS: In CB, the cell recovery rates after CCE were 5.9+/-4.3% in FR 17, 4.2+/-2.1% in FR 24, 19.4+/-11.9% in FR 29, and 61.9+/-11.7% in R/O. In BM, they were 14.9+/-8.2% in FR 17, 17.4+/-13.4% in FR 24, 23.6+/-6.11% in FR 29, and 27.1+/-8.9% in R/O. The distributions of CD133+ and CD34+ cells in CB were more abundant in R/O (2.91%, 1.85%) than in other fractions. In BM, CD133+ and CD34+ cell rates in R/O (5.40%, 2.75%) were similar with those in unmanipulated BM (5.48%, 2.78%). In both CB and BM, there was more CFU-GM and BFU-E in R/O than in other fractions. CONCLUSION: We suggested that the distribution of CD34+ and CD133+ cells might be different between CB and BM. However, the R/O containing relatively large cells could have an effective clonogenicity compared with the unmanipulated sample in both CB and BM.

Usefulness of the IMI Channel of Sysmex SE-9000(TM) Automated Hematology Analyzer Predicting the Optimal Timing of Peripheral Blood Stem Cell Harvest / 임상검사와정도관리

BACKGROUND: An essential prerequisite for successful procurement of sufficient peripheral blood stem cells (PBSC) for engraftment is the optimal timing of collection. The Sysmex SE-9000 automated hematology analyzer provides the immature information (IMI) channel for the identification and counting PBSC. In this study, The optimal timing of PBSC collection was studied using IMI channel. METHODS: 193 peripheral blood stem cell collections were performed from 52 patients with hematologic disorders or solid tumors and 15 donors. Pre-harvest peripheral blood WBC, mononuclear cells (MNC) and IMI were tested and compared with CD34+ cell count and CFU-GM count of harvested products. RESULTS: Peripheral blood WBC and MNC count showed a weak correlation with CD34+ cell yield (r=0.38, P1x10(6)/kg with sensitivity of 88.7%. Positive and negative predictive values of IMI >465/microliter for CD34+ cell >1x10(6)/kg were 65.5% and 87.5%, respectively. CONCLUSIONS: The automated IMI might be used as a simple and efficient indicator of PBSC mobilization and applying variable cutoff values of IMI would be a useful tool to predict the optimal timing of PBSC collection.

Serum Level of G-CSF and GM-CSF and CFU-GM Response to Hematopoietic Growth Factors in a Patient with Cyclic Neutropenia

PURPOSE: Serum levels of G-CSF and GM-CSF were measured and CFU-GM assay using G- CSF, GM-CSF and SCF was conducted to evaluate the influence of hematopoietic growth factor on the precursor cells of cyclic neutropenia. METHODS: A 7-year-old male with cyclic neutropenia was studied. Marrow mononuclear cells were isolated at neutrophil nadir and recovery and cultured in methylcellulose media with or without G-CSF, GM- CSF and SCF. CD34 positive cells were evaluated using flow cytometry. Serum levels of G-CSF and GM-CSF were measured by ELISA. RESULTS: The Numbers of CFU-GM without growth factors were 50 at neutrophil nadir and 33 at the recovery phase in the patient and show increased colony forming capacity. CD34 positive cells were 9.32% at nadir and 14.17% at recovery. Increasement of CFU-GM with G-CSF at nadir and recovery were 46% and 118% and those with GM-CSF were 70% and 78% respectively, compared with 54.4% and 78.2% in control groups. In contrast, the presence of SCF did not enhance CFU-GM number in the patient, but in the control group, increasement with SCF was 28.9 %. There an was inverse relationship between serum G-CSF levels and peripheral neutrophil count whereas those of GM-CSF were constant. CONCLUSION: Serum G-CSF level showed inverse relationship with neutrophil counts. The response of progenitor cells to G-CSF and GM-CSF was not impaired. The presence of SCF did not enhance CFU-GM number in the patient. This result suggests that the abnormality in hematopoiesis in cyclic neutropenia may involve more immature progenitor cells responsive to SCF.

Effects of sepia on hematopoietic stem cells,granulocyte and monocyte progentior cells and peripheral WBC in mice / 中国海洋药物

Objective To investigate the effects of sepia on stem cells,granulocyte and monocyte progentior cells and peripheral WBC in mice.Methods Different dosages of sepia were given to normal and model mice with hematopoietic system impairment respectively.The numbers of CFU-S,CFU-GM and peripheral WBC in normal and model mice were measured respectively with the method of hematopoietic progenitor cells cultured in vitro and the technique of experimental hematology.Results Sepia could enhance the number of CFU-S,CFU-GM and peripheral WBC in normal mice significantly,resist the decrease of CFU-S,CFU-GM,and peripheral WBC in model mice of hemapoiecsis impaired effectively and promote the restoration of those indices mentioned above in model mice significantly.Conclusion Sepia has significant effects on stimulating granulopoiesis in bone marrow in mice.The mechanism may be related to regulating immunological function and inducement GM-CSF and other sorts of cellular factors,which in turn promote the multiplication differentiation of CFU-S and CFU-GM.

Correlation between Progenitor Cell Dose and the Rate of Engraftment in Autologous Peripheral Blood Stem Cell Transplantation and Allogeneic Bone Marrow Transplantation / 대한수혈학회지

BACKGROUND: Bone marrow transplantation (BMT) or peripheral blood stem cell transplantation (PBSCT) following high dose chemotherapy has been an important therapeutic option for patients with hematologic malignancies or some solid tumors. The number of progenitor cells in the collection products has been used to determine the optimum time to stop the collections and to predict the hematopoietic engraftment after transplantation. In this study, we investigated the relationship between end-product cell counts measured by different methods and the influence of the infused cell dose on the engraftment rate. METHODS: Twenty five patients receiving autologous PBSCT and 25 patients receiving allogeneic BMT were studied. The number of total nucleated cells (TNC), of mononuclear cells (MNC), of CD34+ cells, and of CFU-GM (colony-forming unit-granulocyte monocyte) colonies were measured in each collection product. The number of days required to achieve an absolute neutrophil count (ANC) of 0.5x109/L with TNC count of 1.0x109/L and platelet count of 20x109/L without transfusions was taken as an arbitrary measure of the engraftment rate. RESLUTS: A close correlation between CD34+ cells/kg and CFU-GM/kg was observed in both collection products (p<0.05). However, MNC/kg also showed significant correlations with CD34+ cells/kg and CFU-GM/kg in allogeneic bone marrow collection products (p<0.05). The CFU-GM amount in the PBSC products was greater than that in the bone marrow collection products (p<0.05). Time to engraftment was a median of 14 (range 9-50) days in autologous PBSCT group, but 29 (range 17-57) days in allogeneic BMT group. In autologous PBSCT, infused CD34+ cells/kg and CFU-GM/kg correlated significantly with ANC recovery (p<0.05). CONCLUSIONS: The number of CD34+ cells was correlated with that of CFU-GM in the collection products, and the infused cell doses showed positive relation to the engraftment rate in autologous PBSCT. These findings suggest that measurement of CD34+ cell counts alone would be a sufficient parameter to predict the engraftment rate in autologous PBSCT.

Peripheral Blood Stem Cell Collection and Engraftment Kinetics in Pediatric Patients / 대한소아혈액종양학회지

PURPOSE: Peripheral blood stem cell transplantation (PBSCT) has recently been used to rescue from myelosuppression following high-dose chemo-radiotherapy in patients with leukemia and solid tumor. Nevertheless, few data are still available on PBSC collection in pediatric patients, owing to technical problems. The time of stem cell harvest and the mobilization regimen may play important roles in terms of achieving adequate numbers of stem cells by leukapheresis. In this study, we analyse; 1) the technical aspects of leukapheresis as to feasibility and safety, 2) the optimal timing for PBSC collection after cytokine-based mobilizing regimens, 3) the engraftment kinetics. Method: A total of 93 leukapheresis was performed 22 children by Fenwall CS 3000 continuous cell separator, of whom 15 children weighed less than 25 kg. To mobilize hematopoietic stem cells into circulation, hematopoietic growth factor plus chemotherapy were used. Nineteen patients underwent autologous peripheral blood stem cell transplantation. RESULTS: The mean body weight was 25.3 kg (range: 10 to 56 kg). A total of 3 to 12 L of blood was processed (mean 265.4 65.9 mL/kg) for 2.5 to 5 hours (mean 3.15 hours). Extracorporeal line was primed with packed red blood cells below 25 kg. Serious morbidity was not noted. Each apheresis products contained a mean of 2.41 1.63x108 mononuclear cells/kg, 2.83 3.40x106 CD34 cells/kg, 9.30 10.3x104 colony forming unit (CFU-GM)/kg, respectively. Absolute neutrophil count (r=0.38, P<0.01) and CD34 cell count (r=0.65, P<0.001) on the day of leukapheresis seemed to predict the CFU-GM count collected in leukapheresis. A significant statistical correlation between the number of infused CFU-GM and the time to achieve an absolute neutrophil count of greater than 500/mm3 (P<0.01) was found. CONCLUSION: Leukapheresis for PBSCT seemed to be feasible and reliable in pediatric patients, conferring no major additional risks than adult patients, only if red cells are primed in extracorporeal line for small children. Absolute neutrophil count and CD34 cell number seemed to predict the timing of leukapheresis. In the PBSCT patient, engraftment was influenced by the infused CFU-GM count and bone marrow environment.

Megakaryocyte Colony Formation According to the Origin of Hematopoietic Stem Cell / 대한소아혈액종양학회지

BACKGROUND: Development of hematopoietic growth factor made it possible to treat anemia and granulocytopenia following intensive chemotherapy and for thrombocytopenia, recently found thrombopoietin(TPO) is being applied experimentally in several countries. The megakaryocyte colony assay can assess the effect of TPO on the thrombocytopenia resulted from cancer chemotherapy or hematopoietic stem cell transplantation. In vitro colony assay procedures for detecting human erythroid and granulocyte macrophage progenitors have been in widespread use for many years. However, reproducible assay methods for human megakaryocyte progenitors have lagged considerably behind especially in Korea. Duration platelet recovery following transplantation depends on the origin of the hematopoietic cells. Usually thrombocyte recovery is delayed following cord blood stem cell transplantation because of the small amount of cells administered. This study was carried out to investigate and establish the megakaryocyte colony assay of hematopoietic stem cells obtained from the various origin of the hematopoietic stem cells with or without TPO. METHOD: Mononuclear cells of bone marrow, peripheral blood and cord blood were collected following Ficoll density gradient centrifugation and megakaryocyte colony assay was done using MegaCultTM(Stem Cell Tech. Inc., Canada). After liquifying the agarose, mononuclear cells were added and then agarose and cell mixture were dispersed into the two wells of the chamber slide. These slides were incubated for 18~21 days at 37oC, 5% CO2. The megakaryocyte colonies were detected by staining of the cells with a primary antibody to the GPIIb/IIIa antigen, secondary antibody, alkaline phosphatase and Evans Blue in order. Changes of CD34 and GPIIb/IIIa positive cells were also analysed in flask culture using flow cytometry. RESULTS: CD34 positive cells were most abundant in the mononuclear cells of the bone marrow, meanwhile the number of CFU-GM and megakaryocyte colony were greater in the mononuclear cells of the cord blood. After administration of TPO, the cell number of megakaryocyte colony was increased dose dependently, but CFU-GM colony did not show any response to TPO. With flask culture, the cell number was decreased with or without TPO. However adding GM-CSF, IL3 and TPO to cord blood mononuclear cell, the number of the cord blood mononuclear cells was increased on the 5 th day. The amount of CD34 positive cells was increased dose dependently to TPO in one of two cord blood and one peripheral blood. The amount of GPIIb/IIIa positive cells was increased dose dependently to TPO following incubation of all the mononuclear cells. CONCLUSION: This study revealed successful result of megakaryocyte colony assay using MegaCultTM in various kinds of mononuclear cells and suggested that TPO was useful for CFU-mega colony formation. The amount of GPIIb/IIIa positive cells was increased with TPO in the flask culture. Therefore TPO could be useful for assessment of CFU- mega, and could be applied for the in vivo and in vitro expansion of megakaryocytes and platelets.

Influences of Hematopoietic Growth Factors on CFU-GM and CD34 Positive Cells of Mobilized Peripheral Blood Progenitors / 대한혈액학회지

BACKGROUND: Peripheral blood progenitor cells (PBPC) mobilized by hematopoietic growth factors such as G-CSF or GM-CSF are increasingly being used instead of bone marrow to allow hematopoietic reconstitution after myeloablative therapy for variety of malignancies. Ex vivo expansion of PBPC with growth factors leads marked increase in CFU-GM and CD34+ cells. To define the influence of G-CSF and stem cell factor alone and in combination on in vitro culture of PBPC, and to address the question of optimal duration of exposure with growth factors and the effects of G-CSF according to dosages, mobilized progenitors were incubated in liquid media containing autologous serum, stem cell factors and different dose of G-CSF. After 1, 7 and 10 day culture, viable cells were collected and innoculated to methylcellulose media, CFU-GM assay and evaluation of CD33 and CD34 positive cells were done. METHOD: PBPC were obtained from 10 patients by apheresis using COBE Spectra after chemotherapy with or without G-CSF. After Ficoll Hypaque separation, viable 2x106 PBPC were incubated in each 6 sets of RPMI media containing 10% autologous serum and addition of 100ng/mL of stem cell factor, 1,000U/mL of G-CSF, 5,000U/mL of G-CSF, 100ng/mL stem cell factor+1,000U/mL of G-CSF, 100ng/mL stem cell factor+5,000U/mL G-CSF in each culture flask and control group which didn' t contain any growth factor. After 1, 7 and 10 day of culture, viable cells were collected and 1x105 cells were seeded in methylcellulose media containing PHA-LCM and were cultured in duplicate. After 14 day incubation, aggregated with over 50 cells were scored as colony. And 1 day and 10 day of culture of control group and 10 day culture of stem cell factor+5,000U/mL G-CSF group, 1x105 cells were also collected for evaluation of CD33 and CD34 positive cells using flow cytometry. RESULT: CFU-GM were significantly increased even in 1 day exposure with combination of stem cell factor and G-CSF and there showed synergistic effect of stem cell factor and G-CSF. Seven day exposure with growth factor also represented similar increase in CFU-GM. In 10 day exposure of PBPC with growth factor showed significant increase in CFU-GM except 1,000ng/mL G-CSF group. The peak increase of CFU-GM was noted on 7 day culture with G-CSF+stem cell group and on 10 day culture of stem cell group. Number of CD33 & CD34 positive cells were increased in growth factor group and most of them were CD33+ CD34+ cells. There revealed significant positive correlation between CD34+ cells and day 14 CFU-GM. CONCLUSION: G-CSF and stem cell factor act synergistically and their action on ex vivo expansion of PBPC was prominent even in 1 day exposure with stem cell factor and G-CSF. CD34+ cells were also increased under the effect of growth factors and showed good positive corelation with CFU-GM.

Effects of Hematopoietic Growth Factors on the Bone Marrow and Mobilized Peripheral Progenitors from the Same Person / 대한혈액학회지

BACKGROUND: Peripheral blood progenitor cell (PBPC) is now widely used as alternate source to bone marrow for transplantation. The objectives of this study are to compare the clonogenic potential of marrow and mobilized peripheral progenitors obtained from the same person. To examine the activity and effectiveness of G-CSF in different concentration, and to compare the influence of different peroid of exposure with growth factors, mononuclear cells from the bone marrow and peripheral blood were enriched in RPMI media containing different sets of growth factors for various durations. MATERIAL AND METHOD: Bone marrow cells were obtained from 5 lymphoma patients with normal marrow function. PBPCs mobilized by cyclophosphamide plus 10microgram/kg of G-CSF or daily 10microgram/kg of G-CSF alone for 4 days and harvested by leukapheresis with Cobe-Spectra apheresis unit. After Ficoll-Hypaque separation, viable 2x106 mononuclear cells were innoculated in RPMI media containing 10% autologous serum, and 6 sets of different combination of cytokines. Each set of media contains 100ng/mL of stem cell factor, 1,000U/mL of G-CSF, 5,000U/mL of G-CSF, 100ng/mL stem cell factor+1,000U/mL G-CSF, 100ng/mL stem cell factor+5,000U/mL G-CSF and control group which didn't add any growth factor. After 1, 7, 10 days of culture in liquid media, test for viability with trypan blue were done and 1x105 cells were seeded in methylcellulose media and were cultured in duplicate. After 14 days incubation, CFU-GM count were done under inverted microscopy. RESULTS: CFU-GM were generally increased even in 1 day exposure with growth factors than control in both bone marrow and PBPC group. Prominent increase were noted in the combination of 2 cytokines. Seven and 10 days of exposure with growth factors, there showed similar findings but the bone marrow derived mononuclear cells had a tendency of peak level in 1 day exposure but the highest level of CFU-GM in PBPC group was noted in 7 days exposure with growth factors. Assessment of clonogenic activity of marrow and mobilized PBPC, both group yield similar number of CFU-GM. CONCLUSION: These results indicated the bone marrow and PBPC can be enriched exvivo with G-CSF and stem cell factor. The degree of expansion of PBPC and marrow CFU-GM were significantly increased with combination of cytokines. Compare to their clonogenic potential of mononuclear cells from the bone marrow and peripheral blood failed to demonstrate any significant difference.

Effect of Sanazole in Combination with ?-ray Irradiation on In Vivo CFU-GM from Bone Marrow in Mice / 中国药房

OBJECTIVE:To examine the effects of sanazole and of sanazole combining with ?-ray irradiation on the colony formation ratio of granuloid/macrophage committed progenitor cell(CFU-GM)from mouse bone marrow in vivo.METHODS:(1)After a series of doses of sanazole solution(50,100,200mg/kg)was given to mice intravenously,CFU-GMs were separated from mouse bone marrow for evaluating their colony formation ratio.(2)To evaluate the radiosensitization of sanazole,a series of doses of sanazole solution(50,100,200mg/kg)was given to mice intravenously 30min before the mice were exposed to ?-ray irradiation in different doses(5,10,20Gy)respectively.After each treatment,CFU-GMs were separated from mice marrow for counting the ratio of colony formation.RESULTS:(1)Sanazole especially in large doses didn’t showed considerable cytotoxicity to CFU-GM colony formation in mice in vivo.(2)The inhibiting effect of a series of doses of sanazole solution combined with a series of doses of radiation (5,10,20Gy)on colony formation of CFU-GM from mice bone marrow was the same as that of radiation alone.CONCLUSION:Large doses of sanazole showed no obvious effect on the colony formation of CFU-GM of mouse bone marrow in vivo.No radiosensitization to the colony formation of CFU-GM was found in vivo when a series of doses of sanazole in combination with radiation were used.

Treatment of a Case of Malignant Lymphoma by Autologous Peripheral Blood Stem Cell Transplantation / 中国输血杂志

A success in reconstruction of the hematopoietic function of marrow in a case of malignant lymphoma attained by autologous peripheral blood stem cell transplantation after the ultra-high dose chemoradiotherapy was reported. The platelet count of patient was increased to over 20 ? 109/L at the eighth day after PBSC transplantation and was recovered to over 50?109/L at the tenth day after PBSC transplantation. The white blood cell count was increased to over 0. 5?109/ L at the ninth day after PBSC transplantation. The pelvic CT-graphy showed reduction in size of the tumor. And then the patient was outhospitalized due to remission,having been surviving for more than 6 months with routine follow-up. It was suggested that the autologous peripheral blood stem cell transplantation could be a safe and effective suplement therapy for radical cure of malignant tumor.

ENGLISH ABSTRACTS OF ORIGINAL ARTICLES Effect of Mixed Cord Blood Culture on CFU-GM Yield / 中国输血杂志

The amount of CFU-GM colony and cluster yielded after the two units of cord blood were mixed, was observed,using the in vitro CFU-GM culture technique, indicating that the yield of CFU-GM colony and cluster in the mixed culture group was no less than that in the single culture group, so this study can provide the theoritical basis for the transplantation of mixed cord blood hematopoietic stem cells.

Study of Quantity and Quality of Colony Forming Unit-Granulogyte and Macrophase(CFU-GM)in Neonate Cord Blood / 中国输血杂志

The CFU-GM in 30 full-term newborn cord blood were cultured on the mon-olayer agar and compared with those,in quatity and quality,of cord blood,adultbone marrow and peripheral blood,indicating:1.The CFU-GM in newborn cordblood were in a state of the active proliferization with characterization of rapiddivision,early colony appearance,largy colony volume and more filial cell con-tainment;2.The yield of CFU-GM and cluster in full-term newborn cord blo-od ranged between those in the adult bone marrow and peripheral blood but variedgreatly from one individual to another,the yield of CFU-GM in 13 3% cordblood samples was higher than that in the bone marrow cultured at the same time.In addition,the colony type of CFU-GM in cord blood,adult bone marrow andperipheral blood was different,suggesting that the CFU-GM in cord blood mightbe a different subtype.

The Effect of Uremic Plasma on the Proliferative Activity of CFU-GM in in-vitro Culture of Mouse Bone Marrow

The increased susceptibility in patients of chronic renal failure to infection has been reported to be attributed to defects in granulocyte and lymphocyte function and proliferative activity of hematopoietic cells. The definite cause of the frequent infection in uremic patients, however, is still controversial. The effect of uremic plasma on the aspect of the hematopoietic cells has been scarcely been studied. In the present study, mouse bone marrow was cultured with uremic plasma, to evaluate the effect of uremic plasma on the proliferative activity and morphological features of CFU-GM. The results obtained were as follows. 1) The number of colonies in group co-cultured with uremic plasma was more reduced than that of normal plasma group. 2) There was no difference between the group cultured with predialytic uremic plasma and that of postdialytic plasma in number of colonies, macroclusters and microclusters. 3) The forms of colony were granulocytic and monocytic forms at 5 day of culture. Electron microscopically, granulocytes disclosed electron dense azurophilic granules and electrolucent specific granules in the cytoplasm, and monocyte showed numerous vesicles and vacuoles in the cytoplasm which had finger-like projections. 4) The molecular weight of inhibitory factor in the uremic plasma was supposed to be less than 50,000 daltons.

Effect of compounds extracted from spatholobus suberectus dunn on the proliferation of hematopoietic progenitor cell / 中国药理学通报

Aim To study effects of nine compounds extracted from Spatholobus suberectus Dunn (SSD) on proliferation of hematopoietic progenitor cell (HPC) in marrow-depressed mice. Methods Serum pharmacology experiment was used to observe the influence of nine compounds on growth of CFU-E、BFU-E、CFU-GM、CFU-Meg in marrow-depressed mice. Results Compared with the control, all compounds except pyromucic acid and ononin could significantly stimulate the growth of CFU-GM (P

Experimental study on expressing GM-CSF in human bone marrow stromal cells by total saponins of Panax ginseng (TSPG) / 重庆医科大学学报

Objective: To study the relationship between effect of total saponins of Panax ginseng(TSPG) on expression of GM-CSF in human bone marrow stromal cells and modulation of human granulocytopoiesis and monocytopoiesis.Methods:The techniques of culture of hematopoietic progenitor cells and human bone marrow stromal cells in vitro,immunocytochemistry, nucleic acid in situ hybridization were used.Results:TSPG could markedly promote the colony formation of CFU-GM; human bone marrow stromal cells conditioned media prepared with TSPG could significantly enhance the proliferation and differentiation of CFU-GM,and expression of GM-CSF in protein and mRNA level in human bone marrow stromal cells induced by TSPG were much higher than those of the control group.Conclusion:TSPG may directly and/or indirectly promote stromal cells in hematopoietic inductive microenvironment to produce GM-CSF, which further prowote the proliferation and differentiation of human CFU-GM.

Experimental study of the effect of Angelica polysaccharide on proliferation and differentiation of human CFU-GM and HL-60 cells / 重庆医科大学学报

Objective:To study modern biological mechanism for hematonic and antitumor of Angelica Sinensis (oliv) Diels.Methods:By using the techniques of hematopoietic cells culture in vitro,morphological observation,flow cytometry and immunocytochemistry,the effect of Angelica polysaccharide (APS) on proliferation and differentiation of human CFU-GM and promyelocytic leukemia cell line (HL-60) was studied.Results:APS could markedly promote the colony formation of CFU-GM and could significantly inhibit the proliferation of HL-60 in vitro.The inhibitory effect is concerned with the concentration of APS.APS may prevent HL-60 from the Go phase entering the S/G2+M phase,thus prohibit the synthesis of DNA.APS may also promote HL-60 entering the process of apoptosis.Conclusion:APS may not only promote normal hematopoiesis,but also inhibit the proliferation of leukemia cell and it can be a natural inducer for therapy of malignant tumor.