Apoptotic cells suppress mast cell inflammatory responses via the CD300a immunoreceptor

• Published in: Journal of experimental medicine Vol. 209; no. 8; pp. 1493 - 1503
• Main Authors: 小田 ちぐさ, 田原 聡子, 大越 靖, 大河内 信弘, 本多 伸一郎, 渋谷 和子, 渋谷 彰, Nakahashi-Oda Chigusa, Tahara-Hanaoka Satoko, Shoji Masamichi, Okoshi Yasushi, Nakano-Yokomizo Takako, Ohkohchi Nobuhiro, Yasui Teruhito, Kikutani Hitoshi, Honda Shin-ichiro, Shibuya Kazuko, Nagata Shigekazu, Shibuya Akira
• Format: Journal Article
• Language: English
• Published: United States The Rockefeller University Press 30.07.2012
• Subjects: Animals; Apoptosis - immunology; Chemokines - immunology; Chemokines - metabolism; Cytokines - immunology; Cytokines - metabolism; Humans; Inflammation - immunology; Inflammation - metabolism; Inflammation - pathology; Macrophages - immunology; Macrophages - metabolism; Mast Cells - immunology; Mast Cells - metabolism; Mast Cells - pathology; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Neutrophil Infiltration - immunology; Neutrophils - immunology; Neutrophils - metabolism; NIH 3T3 Cells; Phagocytosis - immunology; Phosphatidylserines - immunology; Phosphatidylserines - metabolism; Receptors, Immunologic - immunology; Receptors, Immunologic - metabolism
• ISSN: 0022-1007; 1540-9538; 1540-9538
• DOI: 10.1084/jem.20120096

When a cell undergoes apoptosis, phosphatidylserine (PS) is exposed on the outer leaflet of the plasma membrane. PS acts as an "eat-me" signal to direct phagocytes expressing PS receptors to engulf the apoptotic cell. We recently reported that the immunoreceptor CD300a, which is expressed on myeloid cells, is a PS receptor. We show that CD300a does not facilitate macrophage phagocytosis of apoptotic cells. Instead, CD300a delivers an inhibitory signal in mast cells to suppress production of LPS-induced inflammatory cytokines and chemokines. After cecal ligation and puncture (CLP), when a large number of cells undergo apoptosis in the peritoneal cavity, CD300a-deficient peritoneal mast cells produced more chemoattractant and recruited more neutrophils than did wild-type (WT) mast cells. As a result, CD300a-deficient mice showed increased neutrophil recruitment and improved bacterial clearance in the peritoneal cavity, and survived longer than WT mice. Antibody blockade of CD300a–PS interactions improved bacterial clearance and extended survival of WT mice subjected to CLP. These results indicated that CD300a is a nonphagocytic PS receptor that regulates mast cell inflammatory responses to microbial infections.