Purification of astrocytes from transgenic rodents by fluorescence-activated cell sorting.

The purification of astrocytes by fluorescence-activated cell sorting (FACS) requires that an astrocyte-specific promoter drive the expression of the green fluorescent protein (GFP). Our laboratory uses FACS to acutely isolate astrocytes from young and old tissue as well as to isolate GFP-negative neurons at the end of the FACS sorting to conduct comparative unbiased, large-scale gene expression studies. Because of the relatively harsh nature of FACS sorting, few astrocytes or neurons survive long enough after the sort to be cultured.