scholarly journals Ex Vivo Expansion of Human Cord Blood Progenitor Cells with the Notch Ligand Delta1 Results in Rapid Myeloid Reconstitution In Vivo Following Myeloablative Cord Blood Transplantation

2009 ◽  
Vol 15 (2) ◽  
pp. 11-12
Author(s):  
C. Delaney ◽  
C. Brashem-Stein ◽  
H. Voorhies ◽  
J. Gutman ◽  
S. Heimfeld ◽  
...  
Keyword(s):  
Cord Blood ◽  
Progenitor Cells ◽  
Ex Vivo ◽  
Cord Blood Transplantation ◽  
Ex Vivo Expansion ◽  
Human Cord Blood ◽  
Notch Ligand ◽  
Blood Transplantation

Establishment of Effective B Lymphocyte Ex Vivo Expansion on Human Cord Blood Using TPO, SCF, FL, IL-4, IL-10, and CD40L.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 2882-2882
Author(s):  
Yeung-Chul Mun ◽  
Kyoung-Eun Lee ◽  
Jung Mi Kwon ◽  
Seung-Hyun Nam ◽  
Eun Sun Yoo ◽  
...  
Keyword(s):  
Cord Blood ◽  
B Lymphocytes ◽  
Immune Reconstitution ◽  
B Lymphocyte ◽  
Ex Vivo ◽  
Cord Blood Transplantation ◽  
Ex Vivo Expansion ◽  
Human Cord Blood ◽  
Blood Transplantation ◽  
Activation Assay

Abstract In respect to B lymphocyte-mediated immunity, characteristics of human cord blood are low counts of mature B lymphocytes, deficient expression of CD40L and cytokine production in CD4+ T lymphocytes, defect in the isotype switch of immunoglobulin and the activation of B lymphocytes, and low IgG production of B lymphocytes. These characteristics of the B lymphocyte from human cord blood lead to a delayed B lymphocyte-mediated immune reconstitution and an increased susceptibility to infections after a cord blood transplantation. The mechanism of immunological recostitution after cord blood transplantation has been examined from a variety of viewpoints in experimental models as well as clinical studies. However, problems of sustained immunodeficiency after cord blood transplantation remain to be resolved. The aim of the present study is to establish culture conditions that support the effective B lymphocyte expansion of human cord blood using IL-4, IL-10, and CD40L, to which cytokines are defected in B lymphocyte of human cord blood, and established conditions are compared to previously established cytokine combinations, TPO+SCF+FL in our Lab (Br J Haematol 107:176–185, 1999 & Stem Cells 21:228–235, 2003). To elucidate the effective B lymphocyte-mediated immune reconstitution of cord blood after ex vivo expansion, mononuclear cells, separated from density gradient of Ficoll system, and CD34+ purified cells, isolated from immunomicrobead(MiniMACS) system, were cultured with various combinations of cytokines (TPO+FL+SCF and/or IL-4, IL-10 and CD40L) for 2 weeks or 4 weeks. This then allowed for cytometric analysis after immunofluorescence stain with CD34, CD38 (for HSC analysis) and CD19, IgG and IgM (for B lymphocyte-mediated immune reconstitution) and CD4 (for T helper cell) and CD25 (for lymphocyte activation assay) to be performed. In the B lymphocyte expansion aspect, the immunoglobulin expression, and functional activity, expansion with the TPO+FL+SCF+IL-4+IL-10 combination showed best results in the expression of CD19, CD25, IgG, and IgM. However, the addition of CD40L to those culture condition did not increase expression of CD19, CD25, IgG, and IgM after the expansion of human cord blood. Expansion of CD34+ purified cells was superior to MNCs in the expression of CD19, CD25, IgG, and IgM. In consideration for the duration of cultures, the 2 week culture was superior to the 4 week culture with respect to graft stemness (CD34+CD38- fraction). Our data suggests most superior results were observed from the ex vivo expansion of CD34+ purified cells cultured for 2 weeks with TPO+FL+SCF+IL-4+IL-10, in the B lymphocyte-mediated immune reconstitution and graft stemness aspect. The results of this study warrant further investigation on effective B lymphocyte-mediated immune reconstitution after cord blood transplantation in vivo using ex vivo expanded cord blood.

scholarly journals Activation of OCT4 Enhances Ex Vivo Expansion of Phenotypically Defined and Functionally Engraftable Human Cord Blood Hematopoietic Stem and Progenitor Cells By Regulating HOXB4 Expression

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 4332-4332
Author(s):  
Xinxin Huang ◽  
Scott Cooper ◽  
Hal E. Broxmeyer
Keyword(s):  
Cord Blood ◽  
Progenitor Cells ◽  
Ex Vivo ◽  
Fold Increase ◽  
Lentiviral Vectors ◽  
Ex Vivo Expansion ◽  
Transcriptional Factor ◽  
Human Cord Blood ◽  
Hematopoietic Stem ◽  
Cd34 Cells

Abstract Allogeneic hematopoietic cell transplantation (HCT) is well established as a clinical means to treat patients with hematologic disorders and cancer. Human cord blood (CB) is a viable source of hematopoietic stem cells (HSC) for transplantation. However, numbers of nucleated cells retrieved, as well as limited numbers of HSC/progenitor cells (HPC) present, during collection may be problematic for treatment of adult patients with single CB HCT. One means to address the problem of limiting numbers of HSC/HPC is to ex vivo expand these cells for potential clinical use. While progress has been made in this endeavor, there is still a clinically relevant need for additional means to ex vivo expansion of human HSC and HPC. OCT4, a transcriptional factor, plays an essential role in pluripotency and somatic cell reprogramming, however, the functions of OCT4 in HSC are largely unexplored. We hypothesized that OCT4 is involved in HSC function and expansion, and thus we first evaluated the effects of OAC1 (Oct4-activating compound 1) on ex vivo culture of CB CD34+ cells in the presence of a cocktail of cytokines (SCF, TPO and Flt3L) known to ex vivo expand human HSC. We found that CB CD34+ cells treated with OAC1 for 4 days showed a significant increase (2.8 fold increase, p<0.01) above that of cytokine cocktail in the numbers of rigorously defined HSC by phenotype (Lin-CD34+CD38-CD45RA-CD90+CD49f+) and in vivo repopulating capacity in both primary (3.1 fold increase, p<0.01) and secondary (1.9 fold increase, p<0.01) recipient NSG mice. OAC1 also significantly increased numbers of granulocyte/macrophage (CFU-GM, 2.7 fold increase, p<0.01), erythroid (BFU-E, 2.2 fold increase, p<0.01), and granulocyte, erythroid, macrophage, megakaryocyte (CFU-GEMM, 2.6 fold increase, p<0.01) progenitors above that of cytokine combinations as determined by colony assays. To further confirm the role of OCT4 in human HSC, we performed OCT4 overexpression in CB CD34+ cells using lentiviral vectors and found that overexpression of OCT4 also resulted in significant increase (2.6 fold increase, p<0.01) in the number of phenotypic HSC compared to control vectors. Together, our data indicate that activation of OCT4 by OAC1 or lentiviral vectors enhances ex vivo expansion of cytokine stimulated human CB HSC. HOXB4 is a homeobox transcriptional factor that appears to be an essential regulator of HSC self-renewal. Overexpression of HOXB4 results in high-level ex vivo HSC expansion. It is reported that OCT4 can bind to the promoter region of HOXB4 at the site of 2952 bp from the transcription start point. We hypothesized that activation of OCT4 might work through upregulation of HOXB4 expression to ex vivo expand HSC. We observed that the expression of HOXB4 was largely increased (2.3 fold increase, p<0.01) after culture of CB CD34+ cells with OAC1 compared to vehicle control. siRNA mediated inhibition of OCT4 resulted in the marked reduction of HOXB4 expression (p<0.01) in OAC1-treated cells indicating that OAC1 treatment lead to OCT4-mediated upregulation of HOXB4 expression in HSC. Consistently, siRNA-mediated knockdown of HOXB4 expression led to a significant reduction in the number of Lin-CD34+CD38-CD45RA-CD90+CD49f+ HSC in OAC1-treated cells (p<0.05), suggesting HOXB4 is essential for the generation of primitive HSC in OAC1-treated cells. Our study has identified the OCT4-HOXB4 axis in ex vivo expansion of human CB HSC and sheds light on the potential clinical application of using OAC1 treatment to enhance ex vivo expansion of cytokine stimulated human HSC. Disclosures Broxmeyer: CordUse: Membership on an entity's Board of Directors or advisory committees.

scholarly journals The BET inhibitor CPI203 promotes ex vivo expansion of cord blood long-term repopulating HSCs and megakaryocytes

Blood ◽  
2020 ◽  
Vol 136 (21) ◽  
pp. 2410-2415 ◽  
Author(s):  
Peng Hua ◽  
Joanna Hester ◽  
George Adigbli ◽  
Rong Li ◽  
Bethan Psaila ◽  
...  
Keyword(s):  
Cord Blood ◽  
Progenitor Cells ◽  
Ex Vivo ◽  
Ex Vivo Expansion ◽  
Human Cord Blood ◽  
Hematopoietic Stem ◽  
Bet Inhibitor ◽  
Functional Studies

Abstract Although cytokine-mediated expansion of human hematopoietic stem cells (HSCs) can result in high yields of hematopoietic progenitor cells, this generally occurs at the expense of reduced bone marrow HSC repopulating ability, thereby limiting potential therapeutic applications. Because bromodomain-containing proteins (BCPs) have been demonstrated to regulate mouse HSC self-renewal and stemness, we screened small molecules targeting various BCPs as potential agents for ex vivo expansion of human HSCs. Of 10 compounds tested, only the bromodomain and extra-terminal motif inhibitor CPI203 enhanced the expansion of human cord blood HSCs without losing cell viability in vitro. The expanded cells also demonstrated improved engraftment and repopulation in serial transplantation assays. Transcriptomic and functional studies showed that the expansion of long-term repopulating HSCs was accompanied by synchronized expansion and maturation of megakaryocytes consistent with CPI203-mediated reprogramming of cord blood hematopoietic stem and progenitor cells. This approach may therefore prove beneficial for ex vivo gene editing, for enhanced platelet production, and for the improved usage of cord blood for transplantation research and therapy.

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