Interaction of DAP12 and TREM2 Authored: Garapati, P V, 2012-05-25 Edited: Garapati, P V, 2012-05-25 Pubmed11602640 Pubmed16887962 Pubmed16951310 Pubmed18926286 Reactome Database ID Release 43210300 Reactome, http://www.reactome.org ReactomeREACT_147773 Reviewed: Lanier, Lewis L, 2012-08-09 TREM2 is expressed on dendritic cells and macrophages. Like TREM1 the ligand for TREM2 is unknown. TREM2 signals through DAP12, leading to an increase in intracellular calcium and phosphorylation of ERK1/2 (Sharif & Knapp. 2008). TREM2 on immature dendritic cells triggers upregulation of molecules involved in T cell co-stimulation such as CD86, CD40 and MHC class II, as well as up-regulation of the chemokine receptor CCR7 (Bouchon et al. 2001). In macrophages TREM2 is a negative regulator of inflammatory responses (Hamerman et al. 2006, Turnbull et al. 2006). DAP12 dimer DAP12:TRIM2 complex