Identification of differentialy express genes during the differentiation of stem cells and characterization of mesenchymal progenitor cells

Author(s)

Fernando Henrique Lojudice da Silva

• Document type: Doctoral Thesis
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Conjunto das Químicas (IQ e FCF) (CQ/DBDCQ)
• Defense date: 2008-04-25

Examining board members

Mari Cleide Sogayar; Lygia da Veiga Pereira Carramaschi; José Eduardo Krieger; Aline Maria da Silva; Bianca Silvana Zingales

• Advisor: Mari Cleide Sogayar

Abstract

Diabetes mellitus (DM) defines a number of pathologies caused by the lack or deficient action of the insulin hormone. DM1 is caused by an auto-immune attack to insulin secreting β-pancreatic cells, while DM2 is related to ageing and obesity. Pancreas and islet allo-transplantation constitute therapeutic alternatives, but severe organ shortage and the absolute requirement for immunossupression still constitute important obstacles. Stem cells isolated from the blastocist inner cell mass and from adult tissues are capable of self-renewal and differentiation, and may be utilized for treatment of several diseases. The objectives of this work were: a) to search for new genes involved in the process of differentiation of stem cells into insulin-secreting cells and b) to isolate and characterize mesenchymal stem cells. Murine embryonic stem cells were induced to differentiate in islet-like clusters. Total RNA was utilized to probe DNA microarrays (CodeLink) and the differentially expressed genes were confirmed by Q-PCR, with 16 new genes being identified as associated with differentiation. Two different types of mesenchymal stem cells were isolated from human umbilical cord vein (MSC) and blood (UCB). Immunophenotyping and molecular characterization by Q-PCR, pointed to the existence of two different types of progenitor mesenchymal stem cells in human umbilical cord. (AU)