Isolation of a mammalian neural crest stem cell and environmental control of cell fate choices

Citation

Stemple, Derek Lyle (1993) Isolation of a mammalian neural crest stem cell and environmental control of cell fate choices. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/g1cd-aj32. https://resolver.caltech.edu/CaltechTHESIS:01082013-104637928

Abstract

One question central to the study of developmental biology is: How does phenotypic diversity arise? The neural crest provides an excellent model system for investigations into the nature of cell-fate decisions and generation of lineage diversity. In the studies described here, I have examined two aspects of this question in cell culture. The first aspect concerns the cellular dynamics underlying the cell-fate decisions. A necessary prerequisite to the study lineage diversification is the reliable production of differentiated cells from undifferentiated precursors in a controllable environment. I have developed a system for the growth of rat neural crest cells. The system allows the serial propagation of a defined sub-population of neural crest cells at clonal density. In the system neural crest cells can differentiate into at least two identifiable cell types; peripheral neurons and Schwann cells. By sub-cloning I have been able to address specific predictions made by a stem cell model of neural crest development, and found neural crest cells to possess multipotency, self-renewal and the capacity to divide asymmetrically.

The second aspect of the question addressed in this study concerns the ability of the neural crest cell environment to control the choice of cell fate. I have examined various culture conditions for their ability to affect the choice of cell fate both in clonal cultures and in mass cultures. In the clonal cultures I found that the fate of neural crest cell clones can be altered in an instructive fashion by the composition of the substrate, or by the presence of fetal bovine serum. In mass cultures, we have examined the effect of medium composition on the expression of adrenergic traits and on the expression of a transcription factor, MASH-1, thought to participate in neural determination. Finally, in mass cultures of neo-natal adrenal chromaffin cells, we have examined the effects of basic fibroblast growth factor on neuronal differentiation, mitosis and acquisition of trophic dependence.

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