Figure 1.

(a–c) Expression of DNAX-activation protein 12 (DAP12) and related molecules is remarkably enhanced in inflamed eyes. Total RNA from C57BL/6 naive control mice (a), or from inflamed eyes of mice with experimental autoimmune uveitis (EAU), 14 days following immunization with interphotoreceptor retinoid-binding protein (IRBP) (b and c), was assayed for DAP12, CD45 and DAP12-coupled receptors using specific TaqMan quantitative PCR probe sets. In (a), data are presented as fold of TREM2, the highest receptor we detected. In (b) and (c), levels of each gene were normalized to the level of that gene in naive eyes. All data were normalized using Hprt1 as a house-keeping gene. Data represent the mean of triplicate determinations from cDNA of pools of animals. (d) DAP12 is expressed by eye-infiltrating inflammatory cells. Immunostaining of an eye section of interleukin-1 (IL-1) transgenic mice, with severe ocular inflammaion,²⁶ identifying DAP12 (green) in infiltrating cells in the vitreous, along with CD11b (red), a marker for monocytes/macrophages. In certain positive cells, the two molecules are expressed at different cell loci, whereas in other cells, DAP12 and CD11b are expressed at the same loci, yielding the yellow staining when merged.