Figure 5

Aplec genes are expressed by microglia, but not astrocytes, and several are upregulated following inflammatory stimulation. C-type lectins are mostly known to be expressed by antigen-presenting cells (APCs). In order to determine the source of expression of the Aplec genes, primary astrocyte and microglia cultures were established from DA and PVG rats and exposed to stimulation with TNF-α. Expression of all the Aplec genes was more than 1000-fold higher in microglia compared to astrocytes, thus demonstrating that the C-type lectins here studied are expressed by microglia (A-F). Also, there was strain differences exemplified for instance with upregulation of Clec4a3/Dcir3 only in the PVG microglia (C), while Clecsf6/Dcir1, Clec4a1/Dcir4, Clec4b2/Dcar1 and Clec4e/Mincle were more highly expressed in microglia derived from DA rats (A, D-F). Mcl is not shown, but the expression pattern is similar to that of Mincle. APC: antigen-presenting cell; Aplec: antigen-presenting lectin-like receptor gene complex.