Erin Jones

For stem and progenitor cells to become clinically useful, the factors that influence their differentiation must be better understood. The interaction between progenitor cells and their environment is thought to be one of the main influences on differentiation. Rat adult hippocampal progenitor cells (AHPCs) may differentiate into neurons, astrocytes, or oligodendrocytes. Previously in our group, it has been shown that AHPCs co-cultured with cortical astrocytes on three-dimensionally patterned substrates adsorbed with extracellular matrix proteins preferentially differentiate to neuronal phenotypes as assessed with immunocytochemistry. One hypothesis for this behavior was that astrocyte produced factors became concentrated in the grooves of the pattern due to barriers to diffusion created by the pattern and cell-cell contact. To test this hypothesis, we have devised a system of two-dimensional chemical patterning. We have also tested non-contact mediated effects of astrocytes using semi-permeable culture inserts. Further investigations will include a study of the effects of a gradient of soluble factors and integration of results into a mathematical model.