HMGB1 Is a Key Modulator Of Stress Erythropoiesis During Sepsis

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 8-8 ◽  
Author(s):  
Sergio I Valdés-Ferrer ◽  
Lionel Blanc ◽  
Sebastien Didier ◽  
Johnson M. Liu ◽  
Jeffrey M. Lipton ◽  
...  
Keyword(s):  
Severe Sepsis ◽  
Cord Blood ◽  
Critical Role ◽  
Cecal Ligation ◽  
Erythroid Differentiation ◽  
Erythroid Progenitors ◽  
Stress Erythropoiesis ◽  
Cd34 Cells ◽  
Sepsis Survivors ◽  
Terminal Erythroid Differentiation

Abstract Severe sepsis is a leading cause of death and disability. Anemia in sepsis survivors affects close to 100% of patients after the third day of in-hospital stay, regardless of blood levels on admission. Circulating levels of Erythropoietin (Epo) are low; paradoxically, administration of recombinant Epo is ineffective, and related to increased morbidity. During sepsis, bone Marrow is hypoproliferative. While transfusions can improve outcome in the short term, its use increases the risk of infection and mortality without any sustained beneficial effect. The pathogenesis of anemia during sepsis is unclear. High mobility group box 1 (HMGB1), a cytokine that is a critical mediator of sepsis, is released into circulation a few days after sepsis onset, remaining increased for 8 weeks after severe sepsis. HMGB1 levels are increased for at least 8 weeks in murine models of sepsis survival. To induce severe sepsis, cecal ligation and puncture (CLP) was performed in BALB/c mice. Three days after CLP, mice developed persistent anemia, represented by a significant reduction in hematocrit (Sham=49.8±3.2 vs. CLP=29.7±6.7%; p≤0.001), hemoglobin (16.7±1.2 vs. 9.9±2.4mg/dL; p≤0.001), and red blood cells mass (10.2±0.7 vs. 5.4±1.7 x106/µL; p≤0.001). Anemia persisted for at least 25 days after CLP. In CLP survivors, reticulocyte counts were erratic, and insufficient to the degree and duration of anemia (8.2±0.8 vs. 6.6±2.1%; p=ns). Analysis of terminal erythroid differentiation using CD44 and Ter119 or CD44 and FSC as markers demonstrated a significant decrease in all erythroid progenitors, from proerythroblast to orthochromatic erythroblast. Concomitantly, mice surviving CLP developed splenomegaly. Splenic architecture was disrupted after CLP, with expansion of the red pulp, characteristic of stress erythropoiesis. Analysis of terminal erythroid differentiation demonstrated an increase in the quantity of erythroid progenitors. An anti-HMGB1 mAb (2G7) was administered after CLP. Strikingly, 2G7-treated septic mice were significantly protected from developing anemia, and had levels of hemoglobin and hematocrit similar to sham-operated mice. These results highlight a critical role for HMGB1 as key modulator of stress erythropoiesis in a murine model of sepsis survivors. To get further insight into the function of HMGB1 and translate our findings to the pathophysiology of human erythropoiesis, we used CD34+ cells derived from cord blood. Cord blood-derived CD34+ cells were incubated in MethoCult in the presence or not of HMGB1. HMGB1 induced a dose dependent decrease in CFU-E. In murine sepsis, there is a stepwise elevation of different redox forms of HMGB1, with an early increase in all-thiol (inflammatory), followed by a partially oxidized before a fully oxidized (with no known inflammatory activity) appears. At day 7, all-thiol HMGB1 reduced significantly the number of CFU-E, while the fully oxidized had no significant effect. At day 14, the number of BFU-E was reduced in the presence of HMGB1, and further decreased with all-thiol HMGB1. In conclusion, our findings suggest that CLP is a reproducible model to study anemia of sepsis. In mice surviving sepsis, stress erythropoiesis is consistently found. Administration of anti-HMGB1 monoclonal antibody reverses anemia of murine sepsis, demonstrating that HMGB1 can be a potential target in the anemia of sepsis survivors. Translating the findings to the human system, we found that HMGB1 impairs differentiation of CD34+ cells towards the BFU-E and CFU-E stages in colony formation assays, implying that HMGB1 might play a role early during differentiation. The redox status of HMGB1 is critical for its biological function, since its effects are not retrieved when HMGB1 is fully oxidized. Disclosures: No relevant conflicts of interest to declare.

Pomalidomide Transcriptionally Reprograms Adult Erythroid Progenitors Independently of Ikaros Proteasomal Degradation

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 160-160
Author(s):  
Brian M. Dulmovits ◽  
Abena O. Appiah-Kubi ◽  
Julien Papoin ◽  
John Hale ◽  
Mingzhu He ◽  
...  
Keyword(s):  
Cord Blood ◽  
Board Of Directors ◽  
Peripheral Blood ◽  
Globin Gene ◽  
Erythroid Differentiation ◽  
Erythroid Progenitors ◽  
Advisory Committees ◽  
Cd34 Cells ◽  
Terminal Erythroid Differentiation ◽  
Adult Peripheral Blood

Abstract Pomalidomide, a second-generation immunomodulatory drug, is a fetal hemoglobin (HbF) inducing agent with potential implications for the treatment of β-hemoglobinopathies such as sickle cell disease (SCD). However, its mechanism of action remains unknown. Through an in-depth characterization of human erythropoiesis and globin gene regulatory networks, we now provide evidence that pomalidomide alters transcription networks involved in erythropoiesis and globin switching, thereby leading to a partial reprogramming of adult hematopoietic progenitors toward fetal-like erythropoiesis. Adult peripheral blood CD34+ cells from normal individuals were differentiated toward the red cell lineage using an adapted 3-phase culture system. At day 14 of culture, we observed a reciprocal globin gene switch at the mRNA and protein levels. These results were confirmed by high performance liquid chromatography of hemolysates (HbF/(HbF+HbA): 31.7 ± 1.4% vs. 6.5 ± 0.7% pomalidomide and vehicle, respectively). Next, we studied erythroid differentiation using flow cytometric analyses of the cell surface markers interleukin-3R (IL-3R), glycophorin A (GPA), CD34 and CD36 for early erythroid precursors (BFU-E and CFU-E) as well as GPA, α4-integrin and band3 for terminal erythroid differentiation. While there were no changes in terminal erythroblast maturation, an accumulation of BFU-E in pomalidomide-treated cultures at days 2 and 4 of differentiation was seen, indicating a delay at the BFU-E to CFU-E transition, and also, that pomalidomide exerts its effect in the early-stages of erythropoiesis. Indeed, treatment with pomalidomide during the phase of the culture system that generates erythroid progenitors led to significantly more γ-globin expression than treatment during the phase which proerythroblasts undergo terminal erythroid differentiation. At the molecular level, pomalidomide was found to rapidly and robustly decrease Ikaros (IKZF1) expression exclusively by post-translational targeting to the proteasome. Moreover, pomalidomide selectively reduced the expression of components of key globin regulatory pathways including BCL11A, SOX6, KLF1, GATA1 and LSD1 while not affecting others (e.g. CoREST, GATA2, GFI1B, and HDAC1). Pomalidomide had a transient effect on GATA1 and KLF1 expression. While shRNA knockdown of Ikaros using two different lentiviral constructs delayed erythroid differentiation, it failed to appreciably stimulate HbF production or alter BCL11A expression. These results suggest that the loss of Ikaros alone is insufficient to recapitulate the phenotype observed in pomalidomide-treated conditions. We next compared the expression levels of proteins involved in globin gene regulation among untreated peripheral blood, pomalidomide-treated peripheral blood and untreated cord blood-derived erythroid cells. We found striking similarities between cord blood and pomalidomide-treated adult cells at day 4 of differentiation. Indeed, BCL11A, KLF1, SOX6, LSD1 and GATA1 showed decreased expression levels both in cord blood and pomalidomide-treated adult peripheral blood, while the levels of CoREST, HDAC1 and GATA2 remained unchanged indicating that pomalidomide partially reprograms adult erythroid cells to a fetal-like state. Taken together, our results show that the mechanism underlying reactivation of HbF by pomalidomide involves Ikaros-independent reprogramming of adult erythroid progenitors. Finally, we found that this mechanism is conserved in SCD-derived CD34+ cells. Our work has broad implications for globin switching, as we provide direct evidence that Ikaros does not play a major role in the repression of γ-globin during adult erythropoiesis, and further supports the previously held notion that globin chain production is determined prior to or at the level of CFU-E. Disclosures Allen: Celgene: Research Funding; Bristol Myers Squibb: Equity Ownership; Onconova: Membership on an entity's Board of Directors or advisory committees; Alexion: Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees.

Temporal Differences in Terminal Erythroid Differentiation of Human CD34+ Cells Derived From Cord Blood and Adult Peripheral Blood

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 3200-3200
Author(s):  
Julie Jaffray ◽  
Jingping Hu ◽  
Jie Li ◽  
Xiuli An ◽  
Mohandas Narla
Keyword(s):  
Cord Blood ◽  
Peripheral Blood ◽  
Terminal Differentiation ◽  
Erythroid Differentiation ◽  
Blood Cultures ◽  
Surface Markers ◽  
Cd34 Cells ◽  
Terminal Erythroid Differentiation ◽  
Kinetics Of ◽  
Adult Peripheral Blood

Abstract Abstract 3200 Purified CD34+ cells derived from either cord blood (CB) or peripheral blood (PB) are currently being used to further our molecular and mechanistic understanding of human terminal erythroid differentiation. What is unclear is whether there are differences in the kinetics of terminal erythroid differentiation of CD34+ cells from these two sources. In the present study, we document that terminal differentiation in cultured CD34+ cells purified from peripheral blood is faster than that of CD34+ cells from cord blood. For these studies, we optimized an 18 day, three phase, in vitro culture system using CD34+ cells to obtain enucleated reticulocytes. In this system, proerythroblasts are generated starting at day 6 which further differentiate during the duration of culture to eventually generate reticulocytes. Based on the expression of various membrane surface markers, we used flow cytometry to quantitatively monitor terminal erythroid differentiation from proerythroblasts to enucleated reticulocytes during culture. The three surface markers, alpha-4 integrin, band 3 and CD36 enabled us to clearly distinguish between all distinct stages of terminal erythroid differentiation – proerythroblasts, early- and late- basophilic erythroblasts, polychromatic and orthochromatic erythroblasts. These analyses enabled us to show that CD34+ cells purified and cultured from peripheral blood underwent terminal erythroid differentiation at a faster rate than CD34+ cells from cord blood. Terminal erythroid differentiation in cord blood cultures was delayed on an average of 2 to 3 days compared to peripheral blood. For example, the surface protein expression pattern seen on days 11–12 of cell culture of peripheral CD34+ cells was not achieved in cord blood cultures until day 14. This delay in terminal differentiation was also reflected by increased extents of enucleation in peripheral blood cultures compared to cord blood (culture day 12: 33% enucleation in PB and 7% in CB and on day 14: 45% enucleation in PB and 19% in CB). These findings have enabled us to document significant differences between the kinetics of terminal erythroid differentiation of CD34+ cells derived from fetal cord and adult peripheral blood. While at the present time we do not have a mechanistic understanding for this difference, we are currently exploring if the observed differences may be related to differences in cell cycle dynamics between fetal and adult erythropopiesis. Disclosures: No relevant conflicts of interest to declare.

Signal transducer and activator of transcription 5a (STAT5a) is required for eosinophil differentiation of human cord blood–derived CD34+ cells

Blood ◽  
2003 ◽  
Vol 101 (1) ◽  
pp. 134-142 ◽  
Author(s):  
Miranda Buitenhuis ◽  
Belinda Baltus ◽  
Jan-Willem J. Lammers ◽  
Paul J. Coffer ◽  
Leo Koenderman
Keyword(s):  
Cord Blood ◽  
Target Genes ◽  
Ex Vivo ◽  
Critical Role ◽  
Ectopic Expression ◽  
Hematopoietic Cells ◽  
Myeloid Cell ◽  
Dominant Negative ◽  
Human Cord Blood ◽  
Cd34 Cells

Abstract Signal transducers and activators of transcription (STATs) have been reported to play a critical role in the differentiation of several myeloid cell lines, although the importance of STATs in the differentiation of primary human hematopoietic cells remains to be established. Terminal eosinophil differentiation is induced by interleukin-5 (IL-5), which has also been demonstrated to activate STAT5. We have investigated whether STAT5 plays a critical role during eosinophil differentiation using umbilical cord blood–derived CD34+ cells. In this ex vivo system, STAT5 expression and activation are high early during differentiation, and STAT5 protein expression is down-regulated during the final stages of eosinophil differentiation. Retroviral transductions were performed to ectopically express wild-type and dominant-negative STAT5a (STAT5aΔ750) in CD34+ cells. Transduction of cells with STAT5a resulted in enhanced proliferation compared with cells transduced with empty vector alone. Interestingly, ectopic expression of STAT5a also resulted in accelerated differentiation. In contrast, ectopic expression of STAT5aΔ750 resulted in a block in differentiation, whereas proliferation was also severely inhibited. Similar results were obtained with dominant-negative STAT5b. Forced expression of STAT5a enhanced expression of the STAT5 target genes Bcl-2 andp21WAF/Cip1, suggesting they may be important in STAT5a-mediated eosinophil differentiation. These results demonstrate that STAT5 plays a critical role in eosinophil differentiation of primary human hematopoietic cells.

scholarly journals Epo receptor signaling in macrophages alters the splenic niche to promote erythroid differentiation

Blood ◽  
2020 ◽  
Vol 136 (2) ◽  
pp. 235-246 ◽  
Author(s):  
Yuanting Chen ◽  
Jie Xiang ◽  
Fenghua Qian ◽  
Bastihalli T. Diwakar ◽  
Baiye Ruan ◽  
...  
Keyword(s):  
Erythroid Differentiation ◽  
Peroxisome Proliferator ◽  
Erythroid Progenitors ◽  
Peroxisome Proliferator Activated Receptor ◽  
Hematopoietic Stem ◽  
Stress Erythropoiesis ◽  
Proliferative Stage ◽  
Wnt Ligands ◽  
Canonical Wnt ◽  
Serum Erythropoietin

Abstract Anemic stress induces stress erythropoiesis, which rapidly generates new erythrocytes to restore tissue oxygenation. Stress erythropoiesis is best understood in mice where it is extramedullary and occurs primarily in the spleen. However, both human and mouse stress erythropoiesis use signals and progenitor cells that are distinct from steady-state erythropoiesis. Immature stress erythroid progenitors (SEPs) are derived from short-term hematopoietic stem cells. Although the SEPs are capable of self-renewal, they are erythroid restricted. Inflammation and anemic stress induce the rapid proliferation of SEPs, but they do not differentiate until serum erythropoietin (Epo) levels increase. Here we show that rather than directly regulating SEPs, Epo promotes this transition from proliferation to differentiation by acting on macrophages in the splenic niche. During the proliferative stage, macrophages produce canonical Wnt ligands that promote proliferation and inhibit differentiation. Epo/Stat5-dependent signaling induces the production of bioactive lipid mediators in macrophages. Increased production of prostaglandin J2 (PGJ2) activates peroxisome proliferator-activated receptor γ (PPARγ)-dependent repression of Wnt expression, whereas increased production of prostaglandin E2 (PGE2) promotes the differentiation of SEPs.

scholarly journals Decreased PGC1β expression results in disrupted human erythroid differentiation, impaired hemoglobinization and cell cycle exit

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Taha Sen ◽  
Jun Chen ◽  
Sofie Singbrant
Keyword(s):  
Cell Cycle ◽  
Bone Marrow ◽  
Mitochondrial Function ◽  
Iron Homeostasis ◽  
Erythroid Differentiation ◽  
Refractory Anemia ◽  
Cell Cycle Exit ◽  
Erythroid Progenitors ◽  
Hematopoietic Stem ◽  
Terminal Erythroid Differentiation

AbstractProduction of red blood cells relies on proper mitochondrial function, both for their increased energy demands during differentiation and for proper heme and iron homeostasis. Mutations in genes regulating mitochondrial function have been reported in patients with anemia, yet their pathophysiological role often remains unclear. PGC1β is a critical coactivator of mitochondrial biogenesis, with increased expression during terminal erythroid differentiation. The role of PGC1β has however mainly been studied in skeletal muscle, adipose and hepatic tissues, and its function in erythropoiesis remains largely unknown. Here we show that perturbed PGC1β expression in human hematopoietic stem/progenitor cells from both bone marrow and cord blood results in impaired formation of early erythroid progenitors and delayed terminal erythroid differentiation in vitro, with accumulations of polychromatic erythroblasts, similar to MDS-related refractory anemia. Reduced levels of PGC1β resulted in deregulated expression of iron, heme and globin related genes in polychromatic erythroblasts, and reduced hemoglobin content in the more mature bone marrow derived reticulocytes. Furthermore, PGC1β knock-down resulted in disturbed cell cycle exit with accumulation of erythroblasts in S-phase and enhanced expression of G1-S regulating genes, with smaller reticulocytes as a result. Taken together, we demonstrate that PGC1β is directly involved in production of hemoglobin and regulation of G1-S transition and is ultimately required for proper terminal erythroid differentiation.

Delta-4 Notch ligand promotes erythroid differentiation of human umbilical cord blood CD34+ cells

2006 ◽  
Vol 34 (4) ◽  
pp. 424-432 ◽  
Author(s):  
Akira Sugimoto ◽  
Mayuko Yamamoto ◽  
Motoyuki Suzuki ◽  
Toshiya Inoue ◽  
Shuji Nakamura ◽  
...  
Keyword(s):  
Cord Blood ◽  
Umbilical Cord ◽  
Umbilical Cord Blood ◽  
Erythroid Differentiation ◽  
Human Umbilical Cord Blood ◽  
Human Umbilical Cord ◽  
Notch Ligand ◽  
Cd34 Cells ◽  
Cord Blood Cd34

Studies on Expansion of Erythroid Progenitors and CD34+ Cells among MNCs from Umbilical Cord Blood.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 4124-4124
Author(s):  
Jiexia Zhang ◽  
Huo Tan ◽  
Ping Mao
Keyword(s):  
Cord Blood ◽  
Culture System ◽  
Final Concentration ◽  
Control Group ◽  
Erythroid Progenitors ◽  
Serum Free ◽  
Cd34 Cells ◽  
Group B ◽  
Cells Cultured ◽  
Time Point

Abstract Objective: The experiment is to evaluate the effect of FL, SCF, TPO on CD34+ expansion. Materials and methods: Cord blood samples were collected in heparinized tubes by the Obstetrics and Gynecology Department of Guangzhou first Municipal Peoples hospital. Mononuclear cells(MNCs) were isolated by Ficoll gradient separation. MNCs were culture in 50ml flask containing 6ml serum-free liquid culture system for 14 days at a density of 1*106/ml according to different cytokines combinations. A: control group, no cytokines were added in the culture system. B: cells cultured in the group of SCF+FL+TPO+EPO+IGF-1. C: cells cultured in the group of SCF+FL+TPO. The final concentration of cytokines was 10ng/ml for TPO, 25ng/ml for FL, 25ng/ml for SCF, respectively. Replacing half of media containing the same concentration cytokines on day 6, renewal of Group B and C at day 6, 10 and 14 for final concentration 5U/L EPO, 50ng/ml IGF-1. Part of the cells on day 6, 10 and 14 were counted and detected erythroid progenitors and CFU-GM on semi-solid culture system and the proportion of CD34+, CD34+ CD71+, CD71+ GPA+ cells was detected by FACS. All calculation was performed using SPSS program. Results:1. Proliferation of the total cells: After 10 days, the total cord blood cells were increased 6.89 folds in group B and 3.06 folds in group C respectively. The latter two groups had highly significant differences with the control group A(p<0.01). There is difference between group B and group C 0n day 10. More cells were gained in group B than in group C. (p<0.05) 2. Proliferation of CD34+ cells: The CD34+ cells were increased 4.83 folds in group B containing cytokine FL+TPO+SCF+EPO+IGF-1 and 2.47 folds in group C containing cytokine FL+TPO+SCF on day 10. There is difference between group B and group C on day 10. More cells were gained in group B than in group C.(p<0.05). 3. Proliferation of colony-forming cells: The CFCs were increased 4.3 folds in group B and 2.5 folds in group C on day 10. There is difference between group B and group C on day 10. More cells were gained in group B than in group C(p<0.05). 4. Proliferation of erythroid progenitors: The BFU-E and CFU-E were increased 5.4 folds in group B and 3.1 folds in group C on day 10. There is difference between group B and group C at examined time point(p<0.05). 5. Proliferation of CD34+CD71+cells: The CD34+CD71+ were increased 8.72 folds in group B and 3.37 folds in group C on day 10. There is difference between group B and group C at examined time point(p<0.05). 6. Proliferation of CD71+ GPA+ cells: The CD71+ GPA+ cells were increased 53.4 folds in group B and 30.29 folds in group C at day 10. There is difference between group B and group C at any time (p<0.05). Conclusion: Firstly, in the group of FL+SCF+TPO, CD34+cells and CFC could greatly be expanded from cord blood MNCs in the serum-free culture system. Secondly, in the group of FL+SCF+TPO+EPO+IGF-1, erythroid progenitors could be greatly expanded in the serum-free culture system. Supplying EPO on day 0 is better than supplying on day 6. Thirdly, because the largest number of colony-forming cells such as BFU-E and CFU-E were gained in the TPO+SCF+FL+EPO+IGF-1 group onday 10, the harvest time after cultivation should be set on day 10.

The Role of K-ras Signaling in Erythropoiesis In Vivo.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 3136-3136
Author(s):  
Jing Zhang ◽  
Yangang Liu ◽  
Caroline Beard ◽  
Rudolf Jaenisch ◽  
Tyler Jacks ◽  
...  
Keyword(s):  
Fetal Liver ◽  
Erythroid Differentiation ◽  
Liver Cells ◽  
Ras Signaling ◽  
Erythroid Progenitors ◽  
Akt Activation ◽  
Fetal Liver Cells ◽  
Terminal Erythroid Differentiation

Abstract K-ras plays an important role in hematopoiesis. K-ras-deficient mouse embryos die around E12-E13 with severe anemia. In humans, oncogenic mutations in K-ras gene are identified in ~30% of patients with acute myeloid leukemia. We used mouse primary erythroid progenitors as a model system to study the role of K-ras signaling in vivo. Both Epo- and stem cell factor (SCF) - dependent Akt activation are greatly reduced in K-ras-/- fetal liver cells, whereas other cytokine- induced pathways, including Stat5 and p44/p42 MAP kinase, are activated normally. The reduced Akt activation in erythroid progenitors per se leads to delayed erythroid differentiation. Our data identify K-ras as the major regulator for cytokine-dependent Akt activation, which is important for erythroid differentiation in vivo. Overexpression of oncogenic Ras in primary fetal erythroid progenitors led to their continual proliferation and a block in terminal erythroid differentiation. Similarly, we found that primary fetal liver cells expressing oncogenic K-ras from its endogenous locus undergo abnormal proliferation and terminal erythroid differentiation is partially blocked. We are currently investigating the signal transduction pathways activated by this oncogenic K-ras that underlies these cellular phenotypes.

Overcoming TNF-α Induced Suppression of Erythroid Differentiation of Human Cord Blood CD34+ Cells with Arsenic Trioxide.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 3451-3451
Author(s):  
Jong-Ho Won ◽  
Hee-Jeong Cheong ◽  
Sook-Ja Kim ◽  
Sang-Byung Bae ◽  
Chan-Kyu Kim ◽  
...  
Keyword(s):  
Cord Blood ◽  
Arsenic Trioxide ◽  
Erythroid Differentiation ◽  
Glycophorin A ◽  
Dependent Manner ◽  
Human Cord Blood ◽  
Colony Assay ◽  
Cd34 Cells ◽  
Tnf Α ◽  
Cord Blood Cd34

Abstract The anemia of chronic disease-which encompasses inflammation, infection, tissue injury, and conditions associated with the release of proinflammatory cytokines (such as cancer)- is one of the most common forms of anemia seen clinically. Symptomatic anemia requires treatment. The two major forms of treatment are transfusions and erythropoietin. Arsenic trioxide (As2O3) used to treat human diseases for centuries in traditional Chinese medicine. Our recent studies suggest that low dose of As2O3 induces erythroid differentiation of K562 human leukemic cells and high dose of As2O3 induce apoptosis. In this study, we have investigated in vitro effect of As2O3 on the erythroid differentiation and it could inhibit TNF-α induced suppression of erythroid differentiation of human cord blood CD34+ cells. Expression of glycophorin A was 35.94 ± 7.94% after 7 days culture of human cord blood CD34+ cells and was decreased to 17.63 ± 7.33% when culture of human cord blood CD34+ cells with 100ng/mL of TNF-α. Expression of glycophorin A was increased in dose dependent manner after 7 days treatment with As2O3 and As2O3 increased percentage of glycophorin A in culture with TNF-α compared to TNF-α alone. The results of colony assay of CFU-MIX and BFU-E after culture with various conditions revealed similar patterns with expression of glycophorin A. These results suggest that As2O3 induces erythroid differentiation of human cord blood CD34+ cells and can reverse TNF-α induced suppression of erythroid differentiation of human cord blood CD34+ cells. The BFU-E colony assay of the human cord blood CD34+ cells after culture with TNF-α or/and Arsenic trioxide. The BFU-E colony assay of the human cord blood CD34+ cells after culture with TNF-α or/and Arsenic trioxide.

Sign in / Sign up

Export Citation Format

Share Document