EGF-like module-containing mucin-like hormone receptor-like 1 also known as F4/80 is a protein encoded by the ADGRE1gene.[5][6][7][8][9] EMR1 is a member of the adhesion GPCR family.[10][11]
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.[12]
EMR1 expression in human is restricted to eosinophils and is a specific marker for these cells.[13] The murine homolog of EMR1, F4/80, is a well-known and widely used marker of murine macrophage populations.[14] 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.[15]
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.[16]
Clinical significance
Legrand et al. demonstrated that EMR1 can serve as a therapeutic target for depletion of these cells in eosinophilic disorders by using afucosylated antibodies.[17]
^"Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
^"Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
^Baud V, Chissoe SL, Viegas-Péquignot E, Diriong S, N'Guyen VC, Roe BA, Lipinski M (March 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 (March 1998). "The EGF-TM7 family: unusual structures at the leukocyte surface". Journal of Leukocyte Biology. 63 (3): 271–80. doi:10.1002/jlb.63.3.271. PMID9500513. S2CID6497890.
^Stacey M, Yona S (2011). Adhesion-GPCRs: Structure to Function (Advances in Experimental Medicine and Biology). Berlin: Springer. ISBN 978-1-4419-7912-4.
^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. S2CID6958640.
^Austyn JM, Gordon S (October 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.