Potential Involvement of BIRC5 in Maintaining Pluripotency and Cell Differentiation of Human Stem Cells.

The BIRC5 gene encodes a survivin protein belonging to class III of inhibitors of apoptosis, IAP. This protein serves a dual role. First, it regulates cell death, and second, it is an important regulator of mitosis progression, although its physiological regulatory function has not been fully understood. Many studies have shown and confirmed that survivin is practically absent in mature tissues in nature, while its overexpression has been reported in many cancerous tissues. There is little information about the significance of BIRC5 expression in normal adult human stem cells. This paper presents the study and analysis of survivin expression at the transcription level using qPCR method, in hematopoietic stem cells from peripheral blood mobilized with a granulocyte growth factor, adherent cells derived from the umbilical cord, and normal bone marrow stem cells. The expression of this gene was also examined in the blood of normal healthy individuals. The results of the analysis have shown that the more mature the cells are, the lower the expression of the BIRC5 gene is. The lowest expression has been found in peripheral blood cells, while the highest in normal bone marrow cells. The more the CD34+ and CD105 cells in the tested material are, the higher the BIRC5 expression is. Stem cells from cell culture show higher BIRC5 expression. The study confirms the involvement of BIRC5 from the IAP family in many physiological processes apart from apoptosis inhibition. The possible effect of BIRC5 on cell proliferation; involvement in cell cycle, cell differentiation, survival, and maintenance of stem cells; and the possible effect of IAP on the antineoplastic properties of mesenchymal stem cells have been demonstrated. Our research suggests that BIRC5 may be responsible for the condition of stem cell pluripotency and its high expression may also be responsible for the dedifferentiation of tumor cells.

Phenotypic Characterization of Adherent Cells Population CD34+ CD90+ CD105+ Derived from Wharton's Jelly.

BACKGROUND Mesenchymal stromal cells, MSCs, show expression of specific antigens on their surface. The aim of the study is to assess the phenotype of stem cells like isolated from the umbilical cord with respect to the presence of surface antigens CD34, CD90, and CD105 and differences in the expression of surface antigens in cells isolated from freshly sampled material in comparison with the phenotype of cells from in vitro culture. MATERIAL AND METHODS Stem cells collected from the umbilical cord from healthy patients and then cultured in vitro. To assess the phenotype of stem cells, cytometric analysis was carried out. To assess the phenotype of cells we used fluorescently labelled monoclonal antibodies: APC Mouse anti-human CD34, PC5 Mouse anti-human CD90 and PE Mouse anti-human CD105. RESULTS In the case of cells from the umbilical cord and then cultured in vitro for the period of 10-14 days CD34 expression is lower (69,5%) in comparison with the group of cells not cultured. Not cultured cells were demonstrated 37% of cells co-expression of antigens CD34 and CD105, over 21% of CD34/CD90 cells and over 24% of CD105/CD90. Cultured cells group was showed higher percentage of CD90, CD105, CD34/CD105, CD34/CD90, CD105/CD90 in comparison with not cultured cells. CONCLUSIONS Our reults suggested that adherent cells population from umbilical cord, demonstrate CD34 expression In vivo. Moreover, the phenotype of MSCs, mainly in the context of CD34 expression, may vary depending on the place of collection of cells and the length of growing the cell culture.

Adipose tissue-derived stem cells show considerable promise for regenerative medicine applications.

The stromal-vascular cell fraction (SVF) of adipose tissue can be an abundant source of both multipotent and pluripotent stem cells, known as adipose-derived stem cells or adipose tissue-derived stromal cells (ADSCs). The SVF also contains vascular cells, targeted progenitor cells, and preadipocytes. Stromal cells isolated from adipose tissue express common surface antigens, show the ability to adhere to plastic, and produce forms that resemble fibroblasts. They are characterized by a high proliferation potential and the ability to differentiate into cells of meso-, ecto- and endodermal origin. Although stem cells obtained from an adult organism have smaller capabilities for differentiation in comparison to embryonic and induced pluripotent stem cells (iPSs), the cost of obtaining them is significantly lower. The 40 years of research that mainly focused on the potential of bone marrow stem cells (BMSCs) revealed a number of negative factors: the painful sampling procedure, frequent complications, and small cell yield. The number of stem cells in adipose tissue is relatively large, and obtaining them is less invasive. Sampling through simple procedures such as liposuction performed under local anesthesia is less painful, ensuring patient comfort. The isolated cells are easily grown in culture, and they retain their properties over many passages. That is why adipose tissue has recently been treated as an attractive alternative source of stem cells. Essential aspects of ADSC biology and their use in regenerative medicine will be analyzed in this article.