A microfluidic device with automatic embryos trapping and co-culture with human stromal cells

Abstract Evidence suggests that tumor microenvironment is critically involved in supporting survival of chronic lymphocytic leukemia (CLL) cells. However, the molecular mechanisms of this effect and the clinical significance are not fully understood. We applied a microenvironment model to explore the interaction between CLL cells and stromal cells and to elucidate the role of phosphatidylinositol 3 kinase (PI3-K)/Akt/phosphatase and tensin homolog detected on chromosome 10 (PTEN) cascade in this process and its in vivo relevance. Primary human stromal cells from bone marrow, lymph nodes, and spleen significantly inhibited spontaneous apoptosis of CLL cells. Pan–PI3-K inhibitors (LY294002, wortmannin, PI-103), isotype-specific inhibitors of p110α, p110β, p110γ, and small interfering RNA against PI3-K and Akt1 counteracted the antiapoptotic effect of the stromal cells. Induction of apoptosis was associated with a decrease in phosphatidylinositol-3,4,5-triphosphate, PI3-K–p85, and dephosphorylation of phosphatidylinositol-dependent kinase-1 (PDK-1), Akt1, and PTEN. Freshly isolated peripheral blood mononuclear cells from patients with CLL (n = 44) showed significantly higher levels of phosphorylated Akt1, PDK-1, PTEN, and CK2 than healthy persons (n = 8). CK2 inhibitors (4,5,6,7-tetrabromo-1H-benzotriazole, apigenin, and 5,6-dichloro-1-β-D-ribofuranosylbenzimidazol) decreased phosphorylation of PTEN and Akt, induced apoptosis in CLL cells, and enhanced the response to fludarabine. In conclusion, bone marrow microenvironment modulates the PI3-K/Akt/PTEN cascade and prevents apoptosis of CLL cells. Combined inhibition of PI3-K/Akt and recovery of PTEN activity may represent a novel therapeutic concept for CLL.

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Multipotent human stromal cells improve cardiac function after myocardial infarction in mice without long-term engraftment

Biochemical and Biophysical Research Communications ◽

10.1016/j.bbrc.2007.01.045 ◽

2007 ◽

Vol 354 (3) ◽

pp. 700-706 ◽

Cited By ~ 264

Author(s):

Yoshitaka Iso ◽

Jeffrey L. Spees ◽

Claudia Serrano ◽

Benjamin Bakondi ◽

Radhika Pochampally ◽

...

Keyword(s):

Myocardial Infarction ◽

Cardiac Function ◽

Stromal Cells ◽

Human Stromal Cells

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Ex Vivo Production of Transfusable Red Blood Cells at Large Scale from Cord Blood CD34+ Cells Using a Coculture System with Human Telomerase Catalytic Subunit (hTERT)-Transfected Human Stromal Cells at Early Phase and with Acitivated Macrophage from Cord Blood CD34+ Cells at Late Phase.

Blood ◽

10.1182/blood.v104.11.2701.2701 ◽

2004 ◽

Vol 104 (11) ◽

pp. 2701-2701

Author(s):

Akihito Fujimi ◽

Takuya Matsunaga ◽

Masayoshi Kobune ◽

Yutaka Kawano ◽

Ikuta Tanaka ◽

...

Keyword(s):

Blood Loss ◽

Cord Blood ◽

Stromal Cells ◽

Blood Cells ◽

Large Scale ◽

Acute Blood Loss ◽

Cd34 Cells ◽

Cord Blood Cd34 ◽

Human Stromal Cells

Abstract New sources of red blood cells (RBC) would improve the transfusion capacity of blood centers. Several investigators have previously reported that erythroblasts could be obtained from hematopoietic stem cells including those of cord blood (CB) by in vitro culture. However, transfusion of erythroblasts may not be suitable for supplementation of acute blood loss because it should need some time lag until hemoglobin (RBC) boost in circulation due to the fact that transfused erythroblasts once lodged at bone marrow where they undergo maturation into RBCs which are bound to be released into circulation. We have developed a culture system for producing large quantity of enucleated RBCs (e-RBCs) as well as erythroblasts from CB in vitro: one unit e-RBCs (2 x 1012 RBCs) was obtained from one standard CB unit (corresponding to 2 x 106 CD34+ cells) using a coculture system with hTERT-transfected human stromal cells at early phase followed by with activated macrophage in liquid culture (American Society of Hematology 45th Annual Meeting, SanDiego, 2003). In the present study, we first analyzed the function of those manufactured e-RBCs in comparison of that of adult peripheral blood RBCs (PB-RBCs) or that of eryhthroblasts. The hemoglobin (Hb) content of the e-RBCs quantified by photometric determination was almost equivalent to that of adult PBRBC. A Hb A/Hb F ratio of e-RBC analyzed by high-performance liquid chromatography (HbA: HbF = 35: 65) was between those of CB RBCs (10: 90) and adult PB-RBC (99: 1). Oxygen dissociation curves of e-RBCs measured by Hemox-Analyzer was comparable to that of fresh adult PB-RBCs. The erythroblasts showed adhesive property to stromal cells in vitro but e-RBC did not. When we injected e-RBCs into NOD/SCID mice, they were detectable in circulation while erythroblasts were not. In conclusion, the e-RBCs produced by large-scale culturing system from CB CD34+ cells may be useful for acute blood loss.

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Long-Term Production System of Red Blood Cells Using Human Cord Blood and Stromal Cells

Blood ◽

10.1182/blood.v116.21.3211.3211 ◽

2010 ◽

Vol 116 (21) ◽

pp. 3211-3211

Author(s):

Masayoshi Kobune ◽

Shohei Kikuchi ◽

Kazuyuki Murase ◽

Satoshi Iyama ◽

Tsutomu Sato ◽

...

Keyword(s):

Cord Blood ◽

Progenitor Cells ◽

Stromal Cells ◽

Production System ◽

Ex Vivo ◽

Erythroid Progenitor ◽

Differentiation Potential ◽

Hematopoietic Stem ◽

Human Stromal Cells

Abstract Abstract 3211 We have previously shown that primary human stromal cells and hTERT-transduced human stromal cells (hTERT-stromal cells) support cord blood (CB) hematopoietic stem/progenitor cells. However, it is unclear whether human stromal cells maintain the expansion of erythroid progenitor cells without losing erythroid differentiation potential for a long-term ex vivo culture. In an attempt to evaluate the efficacy of human stromal cells, erythroid induction was conducted by SCF, EPO and IGF-1, 2-week after expansion of CB CD34+ cells with or without human stromal cells. The maturation of erythroid cells were evaluated by morphological findings, transferrin receptor (TfR)/glycophorin A (GPA) expression and hemoglobin (Hb) synthesis (MCH, pg/cells). The number of BFU-E upon 2-week coculture with the hTERT-stromal cells was significantly higher than those without hTERT-stromal cells (BFU-E, 639±102 vs. 4078±1935, the initial cell number of BFU-E was 513±10). Hb concentration of erythroblasts that had been derived from coculture with stromal cells, was significantly higher than that derived from stroma-free condition 14 days after erythroid induction (MCH, 0.78±0.11 vs. 2.62±0.12; p<0.05). Moreover, cobblestone area (CA)-forming cells existed beneath stromal layer weekly produced the large number of BFU-E from 4th week to at least 8th week (the total number of BFU-E, 57246±1288)(Figure A). Notably, these BFU-Es derived from CA could simultaneously differentiate into orthophilic erythroblasts with nearly normal Hb synthesis (MHC, 24.5±6.4 pg/cell)(Figure B) and GPA expression. Furthermore, most of these erythroblasts derived from CA underwent enucleation spontaneously after further 7 days culture. Thus, using hTERT-stromal cells, the long-term ex vivo erythroid production could be attained from CB cells. These findings contribute to constructing long-term of ex vivo erythroid production system using human stromal cells. Disclosures: No relevant conflicts of interest to declare.

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