1.Cooperation between NOD2 and Toll-like receptor 2 ligands in the up-regulation of mouse mFPR2, a G-protein-coupled Abeta42 peptide receptor, in microglial cells.
Chen K1, Zhang L, Huang J, Gong W, Dunlop NM, Wang JM. J Leukoc Biol. 2008 Jun;83(6):1467-75. doi: 10.1189/jlb.0907607. Epub 2008 Feb 25.
Human G-protein-coupled formyl peptide receptor-like 1 and its mouse homologue formyl peptide receptor 2 (mFPR2) mediate the chemotactic activity of a variety of pathogen and host-derived peptides, including amyloid beta(42), a key causative factor in Alzheimer's disease. In mouse microglia, mFPR2 is up-regulated by pathogen-associated molecular patterns and proinflammatory cytokines, as shown, for instance, in our previous study using peptidoglycan (PGN) of Gram(+) bacteria. As PGN and its components have been reported to use TLR2 and an intracellular receptor nucleotide-binding oligomerization domain 2 (NOD2), we investigated the capacity of palmitoyl-cys[(RS)-2, 3-di(palmitoyloxy)-propyl]-Ala-Gly-OH (PamCAG), a specific TLR2 ligand, and muramyl dipeptide (MDP), a NOD2 ligand, to cooperatively regulate the expression and function of mFPR2 in microglia. We found that MDP and PamCAG as well as another TLR2-specific agonist palmitoyl-3-cysteine-serine-lysine-4 (Pam3CSK4), when used alone, each increased the expression of functional mFPR2 in microglial cells, and the combination of MDP and PamCAG or Pam3CSK4 exhibited an additive effect.
