Dual assemblies of an activating immune receptor, MAIR-II, with ITAM-bearing adapters DAP12 and FcRγ chain on peritoneal macrophages

Chigusa Nakahashi, Satoko Tahara-Hanaoka, Naoya Totsuka, Yasushi Okoshi, Toshiyuki Takai, Nobuhiro Ohkohchi, Shin Ichiro Honda, Kazuko Shibuya, Akira Shibuya

Research output: Contribution to journalArticlepeer-review

27 Citations (Scopus)

Abstract

Certain activating immune receptors expressed on myeloid cells noncovalently associate with either DAP12 or FcεRIγ (FcRγ 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 inAb induced secretion of a significant amount of the inflammatory cytokines TNF-α 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 FcRγ chain homodimers in peritoneal macrophages. LPS enhanced the FcRγ chain expression and FcRγ 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 FcRγ chain as well as DAP12. Our findings present the first case of an activating receptor that uses either DAP12 or FcRγ chain as a signaling adapter. The FcRγ chain may provide cooperation with and/or compensation for DAP12 in MAIR-II-mediated inflammatory responses by peritoneal macrophages.

Original languageEnglish
Pages (from-to)765-770
Number of pages6
JournalJournal of Immunology
Volume178
Issue number2
DOIs
Publication statusPublished - 2007 Jan 15

ASJC Scopus subject areas

  • Immunology and Allergy
  • Immunology

Fingerprint Dive into the research topics of 'Dual assemblies of an activating immune receptor, MAIR-II, with ITAM-bearing adapters DAP12 and FcRγ chain on peritoneal macrophages'. Together they form a unique fingerprint.

Cite this