In Vitro Cell Dev Biol Anim. 2011 Jan;47(1):54-63. Epub 2010 Nov 17.

Phuc PV, Nhung TH, Loan DT, Chung DC, Ngoc PK.

Source

Laboratory of Stem Cell Research and Application, University of Science, Vietnam National University, HCMC, Vietnam. pvphuc@hcmuns.edu.vn

Abstract

Umbilical cord blood (UCB)-derived mesenchymal stem cells (MSCs) are multipotent cells. They are able to differentiate into functional cells from not only mesoderm but also endoderm. Many researches showed that cells derived from fresh human UCB could transdifferentiate into insulin-secreting cells. In this study, transdifferentiating potential of cryopreserved human UCB-derived MSCs into insulin-secreting cell was investigated. Fresh human UCB was enriched the mononuclear cells by Ficoll-Paque centrifugation. The mononuclear cell population was cryopreserved in cryo-medium containing Iscove’s modified Dulbecco’s media (IMDM) with 10% DMSO at -196°C for 1 yr. After thawing, mononuclear cells were cultured to isolate MSCs in medium IMDM with 20% FBS supplemented with growth factors. At the fifth passages, MSCs were confirmed by flow cytometry about expression of CD13, CD14, CD34, CD45, CD166, and HLA-DR markers; after that, they were induced to differentiate into adipocytes and osteoblasts. After inducing with specific medium for islet differentiation, there were many clusters of cell like islet at day 14-28. Using real-time reverse transcription polymerase chain reaction (RT-PCR) to analyze the expression of functional genes, the result showed that Nestin, Pdx-1, Ngn3, Ils-1, Pax6, Pax4, Nkx2.2, Nkx6.1, Glut-2, Insulin genes expressed. The results showed that MSCs derived from banked cord blood can differentiate into functional pancreatic islet-like cells in vitro. If human MSCs, especially MSCs from banked cord blood of diabetes patients themselves can be isolated, proliferated, differentiated into functional pancreatic islet-like cells, and transplanted back into them (autologous transplantation), their high-proliferation potency and rejection avoidance will provide one promising therapy for diabetes.

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In Vitro Cell Dev Biol Anim. 2011 Jun;47(5-6):368-75. Epub 2011 Mar 18.

Phuc PV, Lam DH, Ngoc VB, Thu DT, Nguyet NT, Ngoc PK.

Source

Laboratory of Stem cell Research and Application, University of Science, Vietnam National University, Ho Chi Minh, Vietnam. pvphuc@hcmuns.edu.vn

Abstract

Dendritic cells (DCs) are the most professional antigen-presenting cells of the mammalian immune system. They are able to phagocytize, process antigen materials, and then present them to the surface of other cells including T lymphocytes in the immune system. These capabilities make DC therapy become a novel and promising immune-therapeutic approach for cancer treatment as well as for cancer vaccination. Many trials of DC therapy to treat cancers have been performed and have shown their application value. They involve harvesting monocytes or hematopoietic stem cells from a patient and processing them in the laboratory to produce DCs and then reintroduced into a patient in order to activate the immune system. DCs were successfully produced from peripheral, umbilical cord blood-derived monocytes or hematopoietic stem cells. In this research, we produced DCs from human menstrual blood-derived monocytes. Briefly, monocytes were isolated by FACS based on FSC vs. SSC plot from lysed menstrual blood. Obtained monocytes were induced into DCs by a two-step protocol. In the first step, monocytes were incubated in RPMI medium supplemented with 2% FBS, GM-CSF, and IL-4, followed by incubation in RPMI medium supplemented with α-TNF in the second step. Our data showed that induced monocytes had typical morphology of DCs, expressed HLA-DR, HLA-ABC, CD80 and CD86 markers, exhibited uptake of dextran-FITC, stimulated allogenic T cell proliferation, and released IL-12. These results demonstrated that menstrual blood can not only be a source of stromal stem cell but also DCs, which are a potential candidate for immune therapy.

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Hum Cell. 2011 Jun;24(2):86-95. Epub 2011 May 13.

Ngoc PK, Phuc PV, Nhung TH, Thuy DT, Nguyet NT.

Source

Laboratory of Stem Cell Research and Application, University of Science, Vietnam National University, 227 Nguyen Van Cu, District 5, Ho Chi Minh, Vietnam.

Abstract

Type 1 diabetes occurs when pancreatic islet β-cells are damaged and are thus unable to secrete insulin. Pancreas- or islet-grafting therapy offers highly efficient treatment but is limited by inadequate donor islets or pancreases for transplantation. Stem-cell therapy holds tremendous potential and promises to enhance treatment efficiency by overcoming the limitations of traditional therapies. In this study, we evaluated the efficiency of preclinical diabetic treatment. Diabetes was induced in mice by injections of streptozotocin. Mesenchymal stem cells (MSCs) were derived from mouse bone marrow or human umbilical cord blood and subsequently differentiated into insulin-producing cells. These insulin-producing cells were encapsulated in an alginate membrane to form capsules. Finally, these capsules were grafted into diabetic mice by intraperitoneal injection. Treatment efficiency was evaluated by monitoring body weight and blood glucose levels. Immune reactions after transplantation were monitored by counting total white blood cells. Allografting or xenografting of encapsulated insulin-producing cells (IPCs) reduced blood glucose levels and increased body weight following transplantation. Encapsulation with alginate conferred immune isolation and prevented graft rejection. These results provide further evidence supporting the use of allogeneic or xenogeneic MSCs obtained from bone marrow or umbilical cord blood for treating type 1 diabetes.

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Cell Tissue Bank. 2011 Jun 8. [Epub ahead of print]

Phuc PV, Ngoc VB, Lam DH, Tam NT, Viet PQ, Ngoc PK.

Source

Laboratory of Stem cell Research and Application, University of Science, Vietnam National University, Ho Chi Minh, Vietnam, pvphuc@hcmuns.edu.vn.

Abstract

It is known that umbilical cord blood (UCB) is a rich source of stem cells with practical and ethical advantages. Three important types of stem cells which can be harvested from umbilical cord blood and used in disease treatment are hematopoietic stem cells (HSCs), mesenchymal stem cells (MSCs) and endothelial progenitor cells (EPCs). Since these stem cells have shown enormous potential in regenerative medicine, numerous umbilical cord blood banks have been established. In this study, we examined the ability of banked UCB collected to produce three types of stem cells from the same samples with characteristics of HSCs, MSCs and EPCs. We were able to obtain homogeneous plastic rapidly-adherent cells (with characteristics of MSCs), slowly-adherent (with characteristics of EPCs) and non-adherent cells (with characteristics of HSCs) from the mononuclear cell fractions of cryopreserved UCB. Using a protocol of 48 h supernatant transferring, we successfully isolated MSCs which expressed CD13, CD44 and CD90 while CD34, CD45 and CD133 negative, had typical fibroblast-like shape, and was able to differentiate into adipocytes; EPCs which were CD34, and CD90 positive, CD13, CD44, CD45 and CD133 negative, adherent with cobble-like shape; HSCs which formed colonies when cultured in MethoCult medium.

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Onco Targets Ther. 2011;4:71-8. Epub 2011 Jun 21.

Van Phuc P, Nhan PL, Nhung TH, Tam NT, Hoang NM, Tue VG, Thuy DT, Ngoc PK.

Source

Laboratory of Stem Cell Research and Application, University of Science, Vietnam National University, Ho Chi Minh, Vietnam.

Abstract

BACKGROUND:

Cells within breast cancer stem cell populations have been confirmed to have a CD44(+)CD24(-) phenotype. Strong expression of CD44 plays a critical role in numerous types of human cancers. CD44 is involved in cell differentiation, adhesion, and metastasis of cancer cells.

METHODS:

In this study, we reduced CD44 expression in CD44(+)CD24(-) breast cancer stem cells and investigated their sensitivity to an antitumor drug. The CD44(+)CD24(-) breast cancer stem cells were isolated from breast tumors; CD44 expression was downregulated with siRNAs followed by treatment with different concentrations of the antitumor drug.

RESULTS:

The proliferation of CD44 downregulated CD44(+)CD24(-) breast cancer stem cells was decreased after drug treatment. We noticed treated cells were more sensitive to doxorubicin, even at low doses, compared with the control groups.

CONCLUSIONS:

It would appear that expression of CD44 is integral among the CD44(+)CD24(-) cell population. Reducing the expression level of CD44, combined with doxorubicin treatment, yields promising results for eradicating breast cancer stem cells in vitro. This study opens a new direction in treating breast cancer through gene therapy in conjunction with chemotherapy.