Serial analysis of gene expression in a microglial cell line

We used the serial analysis of gene expression (SAGE) method to systematica lly analyze transcripts present in a microglial cell line. Over 10,000 SAGE tags were sequenced, and shown to represent 6,013 unique transcripts. Amon g the diverse transcripts that had not been previously detected in microgli a were those for cytokines such as endothelial monocyte-activating polypept ide I(EMAP I), and for cell surface antigens, including adhesion molecules such as CD9, CD53, CD107a, CD147, CD162 and mast cell high affinity IgE rec eptor. In addition, we detected transcripts that were characteristic of hem atopoietic cells or mesodermal structures, such as E3 protein, Al, EN-7, B9 4, and ufo. Furthermore, the profile contained a transcript, Hn1, that is i mportant in hematopoietic cells and neurological development (Tang et al. M amm Genome 8:695-696, 1997), suggesting the probable neural differentiation of microglia from the hematopoietic system in development, Messenger RNA e xpression of these genes was confirmed by RT-PCR in primary cultures of mic roglia. Significantly, this is the first systematic profiling of the genes expressed in a microglial cell line. The identification and further charact erization of the genes described here should provide potential new targets for the study of microglial biology. (C) 1999 Wiley-Liss, Inc.