Isolation of Oct4+, Nanog+ and SOX2- mesenchymal cells from peripheral blood of a diabetes mellitus patient.

Diabetes mellitus is a chronic metabolic disorder that affects millions of people worldwide. The most common form is type 2 diabetes mellitus, which results in impaired beta cell function combined with insulin resistance in peripheral organs. One recently proposed treatment approach is the use of adult stem cells derived from bone marrow in autologous stem cell transplantation. Alternatively, peripheral blood can be obtained in a more non-invasive manner. In this study, we isolated and cultured mesenchymal cells (MCs) from the peripheral blood of a diabetes mellitus patient. The cultured cells were large and elongated and had an in vitro migratory capacity in the culture dish. They expressed embryonic stem cell pluripotency markers Nanog and Oct 4 as well as mesenchymal markers CD105 and CD13, and they lacked expression of hematopoietic marker CD45. These characteristics suggest that these cells have a mesenchymal phenotype similar to that obtained from bone marrow cells. The SOX2 gene was downregulated in both the peripheral blood cells and the isolated mesenchymal cell line, indicating a defective mechanism of SOX2 in diabetes mellitus. The overall results of study demonstrate that peripheral blood can be used as a source of MCs from diabetes mellitus patients for use in future regenerative stem cell therapy and that this particular model system may be useful to study the mechanism of diabetes mellitus involving downregulation of the SOX2 cascade.

Ascorbic acid induces in vitro proliferation of human subcutaneous adipose tissue derived mesenchymal stem cells with upregulation of embryonic stem cell pluripotency markers Oct4 and SOX 2.

Mesenchymal stem cells (MSCs) have immense therapeutic potential because of their ability to self-renew and differentiate into various connective tissue lineages. The in vitro proliferation and expansion of these cells is necessary for their use in stem cell therapy. Recently our group has developed and characterized mesenchymal stem cells from subcutaneous and visceral adipose tissue. We observed that these cells show a slower growth rate at higher passages and therefore decided to develop a supplemented medium, which will induce proliferation. Choi et al. have recently shown that the use of ascorbic acid enhances the proliferation of bone marrow derived MSCs. We therefore studied the effect of ascorbic acid on the proliferation of MSCs and characterized their phenotypes using stem cell specific molecular markers. It was observed that the use of 250 µM ascorbic acid promoted the significant growth of MSCs without loss of phenotype and differentiation potential. There was no considerable change in gene expression of cell surface markers CD105, CD13, Nanog, leukemia inhibitory factor (LIF) and Keratin 18. Moreover, the MSCs maintained in the medium supplemented with ascorbic acid for a period of 4 weeks showed increase in pluripotency markers Oct4 and SOX 2. Also cells in the experimental group retained the typical spindle shaped morphology. Thus, this study emphasizes the development of suitable growth medium for expansion of MSCs and maintenance of their undifferentiated state for further therapeutic use.