Human mesenchymal stem cells xenografted directly to rat liver are differentiated into human hepatocytes without fusion

Abstract Hepatic transdifferentiation of bone marrow cells has been previously demonstrated by intravenous administration of donor cells, which may recirculate to the liver after undergoing proliferation and differentiation in the recipient's bone marrow. In the present study, to elucidate which cellular components of human bone marrow more potently differentiate into hepatocytes, we fractionated human bone marrow cells into mesenchymal stem cells (MSCs), CD34+ cells, and non-MSCs/CD34- cells and examined them by directly xenografting to allylalcohol (AA)-treated rat liver. Hepatocyte-like cells, as revealed by positive immunostaining for human-specific alpha-fetoprotein (AFP), albumin (Alb), cytokeratin 19 (CK19), cytokeratin 18 (CK18), and asialoglycoprotein receptor (AGPR), and by reverse transcription-polymerase chain reaction (RT-PCR) for expression of AFP and Alb mRNA, were observed only in recipient livers with MSC fractions. Cell fusion was not likely involved since both human and rat chromosomes were independently identified by fluorescence in situ hybridization (FISH). The differentiation appeared to follow the process of hepatic ontogeny, reprogramming of gene expression in the genome of MSCs, as evidenced by expression of the AFP gene at an early stage and the albumin gene at a later stage. In conclusion, we have demonstrated that MSCs are the most potent component in hepatic differentiation, as revealed by directly xenografting into rat livers. (Blood. 2005;106:756-763)

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Proliferation of Human Bone Marrow Cells in Diffusion Chambers Implanted Into Normal or Irradiated Mice

Blood ◽

10.1182/blood.v40.2.163.163 ◽

1972 ◽

Vol 40 (2) ◽

pp. 163-173 ◽

Cited By ~ 62

Author(s):

Arne Boyum ◽

Werner Boecker ◽

Arland L. Carsten ◽

Eugene P. Cronkite

Keyword(s):

Stem Cells ◽

Bone Marrow ◽

Bone Marrow Cells ◽

Human Bone ◽

Human Bone Marrow ◽

Culture Period ◽

Diffusion Chambers ◽

Significant Difference ◽

Lymphocyte Number ◽

Marrow Cells

Abstract Diffusion chambers containing normal, human bone marrow cells were implanted in the abdominal cavity of normal and irradiated mice. Granulocytic cells and macrophages proliferated in the chambers. The number of cells in the granulocytic series recovered from the chambers dropped to 60% after 1 day; during the next 7 days it varied between 40% and 60% of the inoculated number of granulocytes, with no difference between irradiated and non-irradiated animals. From day 9 the yield of cells in granulocytic series increased in chambers from irradiated animals, and a higher percentage of cells were in the proliferating pool of the granulocytic series. Simultaneously, the cell yield in chambers from normal animals dropped markedly and consisted mostly of mature granulocytes. In both groups the percentage of eosinophilic cells increased significantly during the last part of the culture period. The enhanced growth in the irradiated mice suggests an increased self-renewal of granulocytic stem cells, leading to a larger yield of differentiated granulocytic cells later in the culture period. A shortened generation time and/or increased cloning efficiency of stem cells may also contribute to the enhanced granulocyte production. The suppression of the immune reactivity by irradiation of the host animals may allow better proliferation by delaying production of cytotoxic antibodies against the xenogenic human cells. The number of macrophages increased gradually, and there was no significant difference between irradiated and nonirradiated animals. The lymphocyte number decreased after implantation and varied between 30% and 50% of the inoculated number. From day 11, the lymphocyte number dropped more in normal animals than in irradiated animals.

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Toll-Like Receptors 2 and 4 Mediate the Capacity of Human Bone Marrow-Derived Mesenchymal Stem Cells to Support the Proliferation and Differentiation of CD34+ Cells In a Non-Synergistic Way.

Blood ◽

10.1182/blood.v116.21.3850.3850 ◽

2010 ◽

Vol 116 (21) ◽

pp. 3850-3850

Author(s):

Xingbing Wang ◽

Qiansong Cheng ◽

Jian Wang ◽

Liang Xia ◽

Xuhan Zhang ◽

...

Keyword(s):

Stem Cells ◽

Bone Marrow ◽

Mesenchymal Stem Cells ◽

Research Funding ◽

Human Bone ◽

Human Bone Marrow ◽

Toll Like Receptors ◽

Myeloid Lineage ◽

Cd34 Cells ◽

Proliferation And Differentiation

Abstract Abstract 3850 Human bone marrow-derived mesenchymal stem cells (BM-MSCs) are multipotent nonhematopoietic progenitor cells, which can differentiate into osteoblasts, adipocytes, chondrocytes and other tissues. The most important function of BM-MSCs is to support hematopoiesis. Toll-like receptors (TLRs) are a conserved family of receptors that can be activated by both pathogen components and mammalian endogenous molecules such as heat-shock proteins and extracellular matrix breakdown products. In the past a few year, several studies reported that TLRs are expressed in hematopoietic and non-hematopoietic to modulate their biological functions. We hypothesized that MSCs are equipped with TLRs that enable them to dynamically change hematopoiesis-related cytokines expression pattern and level by sensing correspondent agonists, thus efficiently supporting hematopoiesis. In this study, BM-MSCs were analyzed for mRNA expression of TLR 1–9 by reverse transcription-polymerase chain reaction. TLR 1–6, but not TLR 7–9 were expressed by MSCs. The expression of TLR2 and TLR4 was also confirmed by flow cytometic assay. We further explored the role of TLR2 and TLR4 in mediating the capacity of MSC to support the proliferation and differentiation of CD34+ cells. The pre-stimulation with TLR2 agonists (Pam3Cys) or TLR4 agonists (LPS) enable MSCs to enhance CD34+ cells proliferation and promote CD34+ cells differentiation towards the myeloid lineage (CD33+, CD11b+), as well as granulocyte colony formation by those cells. The production of interleukin 8 (IL-8), IL-11, stem cell factor (SCF), granulocyte colony-stimulating factor (CSF), macrophage CSF and granulocyte-macrophage CSF were also increased by stimulated MSCs. Interestingly, although Pam3Cys and LPS displayed different inductive magnitudes, they have no synergistic effect on MSCs. We hypothesized there may be some antagonistic effect between TLR2 and TLR4 intracellular signal conductive pathway, or they can downregulate the expressive level of the TLRs on MSCs. Together, our findings suggest that TLR2 and TLR4 signalings may indirectly regulate hematopoiesis by modulating MSCs' functions. The increased haemopoietic proliferation and myeloid lineage differentiation could be mediated, at least in part, by augmented hematopoiesis-related cytokine production. Disclosures: Wang: National Natural Science Foundation (30700329): Research Funding; Anhui Provincial Outstanding Young Investigator Program (08040106810): Research Funding; Fund of Anhui Provincial “115” Industrial Innovation Program: Research Funding.

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The Effect of Erythropoietin on Human Bone Marrow Cells In Vitro. I. Studies of Nine Cases of Bone Marrow Failure

Blood ◽

10.1182/blood.v37.6.624.624 ◽

1971 ◽

Vol 37 (6) ◽

pp. 624-633 ◽

Cited By ~ 5

Author(s):

HIDEAKI MIZOGUCHI ◽

YASUSADA MIURA ◽

FUMIMARO TAKAKU ◽

SHIGERU SASSA ◽

SHYOZO CHIBA ◽

...

Keyword(s):

Stem Cells ◽

Bone Marrow ◽

Bone Marrow Cells ◽

Bone Marrow Failure ◽

Human Bone ◽

Human Bone Marrow ◽

Group A ◽

In Vitro Response ◽

Marrow Cells

Abstract The in vitro response to erythropoietin of bone marrow from nine patients with bone marrow failure were studied. Two types of patients were observed, those in which the marrow was responsive to erythropoietin and those which were nonresponsive. Ferrokinetic data corresponded well with the response to erythropoietin in vitro. In the nonresponsive group, a recovery of sensitivity to erythropoietin was observed when the patients improved clinically. The nature of the bone marrow failure was discussed in relation to erythropoietin and stem cells.

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