We report here the application of magnetic cell separation in microarray experiment to understand Drosophila gliogenesis during early embryogenesis. At stage 11, neuroectodermal cells were labeled by a fusion transmembrane protein, mCD8-GFP, in the wild-type embryos as wells as in the embryos where glide/gcm was overexpressed. Following the cell dissociation, neuroectodermal cells were purified by using the commercial available anti-mCD8 microbeads. Microarray experiments based on prepared neuroectodermal cells from wild-type embryos verse glide/gcm overexpressed embryos at stage 11 have revealed 76 gene differentially regulated by overexpression of glide/gcm. Among them, there are 11 genes have already been shown to be regulated by glide/gcm in the previous publications. Additionally, we have identified 4 more new glide/gcm-regulated genes by in situ hybridization or immunohistochemical staining. It is very convincing that reduction of the tissue complexity by cell purification leads to low false positives in microarray experiment.
