| First Author | Nakahashi C | Year | 2007 |
| Journal | J Immunol | Volume | 178 |
| Issue | 2 | Pages | 765-70 |
| PubMed ID | 17202337 | Mgi Jnum | J:142632 |
| Mgi Id | MGI:3821843 | Doi | 10.4049/jimmunol.178.2.765 |
| Citation | Nakahashi C, et al. (2007) Dual assemblies of an activating immune receptor, MAIR-II, with ITAM-bearing adapters DAP12 and FcRgamma chain on peritoneal macrophages. J Immunol 178(2):765-70 |
| abstractText | Certain activating immune receptors expressed on myeloid cells noncovalently associate with either DAP12 or FcepsilonRIgamma (FcRgamma chain), the ITAM-bearing transmembrane adapter proteins. An activating receptor, myeloid-associated Ig-like receptor (MAIR) II, is expressed on a subset of B cells and macrophages in the spleen and peritoneal cavity of mice and associates with DAP12 in these cells. However, we demonstrate here that cross-linking MAIR-II with mAb induced secretion of a significant amount of the inflammatory cytokines TNF-alpha and IL-6 from DAP12(-/-) as well as wild-type (WT) peritoneal macrophages. We show that MAIR-II associates with not only DAP12 but also FcRgamma chain homodimers in peritoneal macrophages. LPS enhanced the FcRgamma chain expression and FcRgamma chain-dependent cell surface expression of MAIR-II and had additive effects on MAIR-II-mediated inflammatory cytokine secretion from peritoneal macrophages. The lysine residue in the transmembrane region of MAIR-II was involved in the association with FcRgamma chain as well as DAP12. Our findings present the first case of an activating receptor that uses either DAP12 or FcRgamma chain as a signaling adapter. The FcRgamma chain may provide cooperation with and/or compensation for DAP12 in MAIR-II-mediated inflammatory responses by peritoneal macrophages. |
