The effects of CNTF and BMP on neural stem cell differentiation

The neurons, oligodendrocytes and astrocytes in the central neural system (CNS) are vital for our survival. Yet we know very little about the regulation of the cells and their development. To investigate this deeper two growth factors, Ciliary Neurotrophic Factor (CNTF) and Bone Morphogenetic Protein (BMP), previously know to somehow be involved in the differentiation of neural stem cells were used in this in vitro study. Neural stem cells from mouse embryo cortex were differentiated into neurons, oligodendrocytes and astrocytes. The differentiation occurred in the presence CNTF, BMP or no growth factor at all. In the first part of this study, the cell cultures were immunostained followed by calculation of the cell numbers in different treatments. The total amount of living cells in the cultures were higher in the culture treated with CNTF or BMP compared to the controls. This clearly shows the importance of growth factors in the differentiation process. Furthermore the differentiation to oligodendrocytes specific was promoted by both of the growth factors. This result was unexpected since other studies have shown that CNTF and BMP inhibit oligodendrocyte differentiation. In the second part of this study, dead cells were added to half of the cell cultures. The protein expression of the phagocytosis markers Lamp-1 and Megf10 were detected with the use of western blot. As expected, cell cultures with dead cells added had a higher expression of Lamp-1 and Megf10. The astrocytes apparently engulf the dead cells. Stem cells differentiated into astrocytes in the presence of CNTF or BMP seems to be the most active in the phagocytosis process since the protein expression in those samples were the highest.