Investigation of the differentiation course of mouse embryonic stem cell depending on the extracellular matrix concentration

Maintenance and specification of the cellular components with constitution of the tissue form are important processes in both in the adult and developing organisms Pluripotent embryonic stem cells are obtained from the inner cell mass. Differentiation of embryonic stem cells gradually occurs and pluripotency of the cells progressively decreases. Cells continuously receive both intracellular and extracellular signals, in this way, regulate the inner metabolic activity. Niche of the stem cells are known to be one of the most important determinants for the differentiation and there are several hydrogels used for mimicking the extracellular matrix (ECM) pattern in vivo in in vitro conditions. One of the most widely used hydrogels is matrigel. However, there is limited knowledge about the additive effect of the matrigel and its protein concentration for differentiation capacity of the stem cell. To detect and distinguish differentiation at molecular level, there are several embryonic stem cell markers as stage-specific embryonic antigen 1 (SSEA-1) and Oct3/4. SSEA-1 markers are used in the mouse undifferentiated embryonic stem cell identification. OPN is one of the osteogenic markers in differentiation, and known to be expressed in osteoblastic cells. Our study aimed to improve our ability to manipulate the mouse Embryonic Stem Cell (mESC) capacity and differentiation capability via cell cycle, immunofluorescence (IF). We selected three different concentrations (2, 4, 6 mg/ml) and focused on three time points (day 1, 3, 6). To observe stem cell identity and osteoblastic differentiation, we stained SSEA-1 and osteopontin (OPN=SPP1), respectively. We concluded that the characteristics of the mESCs vary due to ECM protein concentration, shown by cell cycle and IF. In future studies, improvement the knowledge about stem cell differentiation in vitro will be the groundwork of the cell-tissue replacement in the field of regenerative medicine. Moreover, mESC interactions with ECM may shed light upon the carcinogenesis, epithelial mesenchymal transition (EMT) and fibrotic connective tissue based mechanisms, since they use common signaling pathways.