EGF-like module-containing mucin-like hormone receptor-like 1 also known as F4/80 is a protein encoded by the ADGRE1gene. EMR1 is a member of the adhesion GPCR family. Adhesion GPCRs are characterized by an extended extracellular region often possessing N-terminal protein modules that is linked to a TM7 region via a domain known as the GPCR-Autoproteolysis INducing (GAIN) domain.
EMR1 expression in human is restricted to eosinophils and is a specific marker for these cells. The murine homolog of EMR1, F4/80, is a well-known and widely used marker of murine macrophage populations. The N-terminal fragment (NTF) of EMR1 contains 4-6 Epidermal Growth Factor-like (EGF-like) domains in human and 4-7 EGF-like domains in the mouse.
Utilizing F4/80 knockout mice, Lin et al. showed that F4/80 is not necessary for the development of tissue macrophages but is required for the induction of efferent CD8+ regulatory T cells needed for peripheral tolerance.
^Baud V, Chissoe SL, Viegas-Péquignot E, Diriong S, N'Guyen VC, Roe BA, Lipinski M (Mar 1995). "EMR1, an unusual member in the family of hormone receptors with seven transmembrane segments". Genomics. 26 (2): 334–44. doi:10.1016/0888-7543(95)80218-B. PMID7601460.
^McKnight AJ, Gordon S (Mar 1998). "The EGF-TM7 family: unusual structures at the leukocyte surface". Journal of Leukocyte Biology. 63 (3): 271–80. PMID9500513.
^Leenen PJ, de Bruijn MF, Voerman JS, Campbell PA, van Ewijk W (Sep 1994). "Markers of mouse macrophage development detected by monoclonal antibodies". Journal of Immunological Methods. 174 (1-2): 5–19. doi:10.1016/0022-1759(94)90005-1. PMID8083537.
^Stacey M, Yona S (2011). Adhesion-GPCRs: Structure to Function (Advances in Experimental Medicine and Biology). Berlin: Springer. ISBN1-4419-7912-3.
^Langenhan, T; Aust, G; Hamann, J (21 May 2013). "Sticky signaling--adhesion class G protein-coupled receptors take the stage.". Science signaling. 6 (276): re3. doi:10.1126/scisignal.2003825. PMID23695165.
^Hamann J, Koning N, Pouwels W, Ulfman LH, van Eijk M, Stacey M, Lin HH, Gordon S, Kwakkenbos MJ (Oct 2007). "EMR1, the human homolog of F4/80, is an eosinophil-specific receptor". European Journal of Immunology. 37 (10): 2797–802. doi:10.1002/eji.200737553. PMID17823986.
^Austyn JM, Gordon S (Oct 1981). "F4/80, a monoclonal antibody directed specifically against the mouse macrophage". European Journal of Immunology. 11 (10): 805–15. doi:10.1002/eji.1830111013. PMID7308288.
^Lin HH, Faunce DE, Stacey M, Terajewicz A, Nakamura T, Zhang-Hoover J, Kerley M, Mucenski ML, Gordon S, Stein-Streilein J (May 2005). "The macrophage F4/80 receptor is required for the induction of antigen-specific efferent regulatory T cells in peripheral tolerance". The Journal of Experimental Medicine. 201 (10): 1615–25. doi:10.1084/jem.20042307. PMID15883173.
^Legrand F, Tomasevic N, Simakova O, Lee CC, Wang Z, Raffeld M, Makiya MA, Palath V, Leung J, Baer M, Yarranton G, Maric I, Bebbington C, Klion AD (May 2014). "The eosinophil surface receptor epidermal growth factor-like module containing mucin-like hormone receptor 1 (EMR1): a novel therapeutic target for eosinophilic disorders". The Journal of Allergy and Clinical Immunology. 133 (5): 1439–47, 1447.e1–8. doi:10.1016/j.jaci.2013.11.041. PMID24530099.