Characterisation of stem cell expression using two-dimensional electrophoresis

Stem cells were isolated from foetal human brain tissue and induced to proliferate using the mitogens epidermal growth factor (EFG) and fibroblast growth factor (FGF). Under these conditions the dividing cells formed spheres which could be maintained in an undifferentiated state for extended periods of time. Following removal of the mitogen and addition of serum, the human stem cells rapidly began to differentiate. Samples from differentiated and undifferentiated cultures were lysed and analysed using two-dimensional (2-D) electrophoresis, a powerful technique for the separation and characterisation of proteins in complex mixtures. After 1 h post-differentiation, marked differences in protein expression could be observed between undifferentiated and differentiated stem cell samples.