Introduction
Upon infection, the host immune system must integrate a constellation of extracellular signals to orchestrate the migration and activation of the multiple cell types required for the development an appropriate response. The host’s response must be strong enough to eliminate the pathogen, but at the same time regulated so as not to inflict unwarranted damage to bystander tissues. Cells of the innate immune system are the first to be activated following infection, and therefore, typically play both a vital early effector role and a key regulatory role in both the development and attenuation of the inflammatory response. In addition, innate immune cells are critical in shaping the subsequent adaptive immune response.
As an adaptation to this critical role, innate immune cells express many regulatory receptors. Unlike T cells and B cells, the response of innate immune cells is not generally regulated through antigen specific receptors. Instead, they detect infection through more generalized methods such as the recognition of pathogen-associated molecular patterns or screening for indicators of stress such as modification or absence of MHC class I molecules. Since innate immune responses are not antigen specific, the system requires tight regulatory controls that interpret signals from several receptor-ligand interactions. One mechanism for this regulation is the expression of Paired Receptor Systems.
Paired receptors tune the inflammatory response. Many of the inhibitory receptors within paired systems participate in self tolerance by recognizing ubiquitously expressed endogenous molecules such as MHC class I molecules, cell surface sialic acid modified proteins, or CD200. During infection these markers of self are either downregulated or modified. At the same time, stress related molecules are expressed. The activating siblings of Paired Receptor Systems may recognize these “alert” molecules up-regulated as a consequence of infection or may bind constitutively expressed ligands that gain advantage as inhibitory ligands are downregulated. Alternatively, activating siblings may directly recognize pathogen associated or encoded ligands. Perhaps resolution of this issue will follow the positive identification of more activating ligands. Regardless, it is clear that these paired systems play critical roles in overall regulation of innate immunity.
In this table we review paired receptors involved in the innate immune system. For purposes of this review we define “Paired Receptors” as families of related membrane proteins that show the following characteristics: 1) encoded by different genes, but located as a gene cluster on a given chromosomes, 2) have significant homology within their extracellular domains, 3) expressed on overlapping immune populations and, 4) confirmed to have both activating and inhibitory members. For simplicity in nomenclature, whenever possible we have used the official gene nomenclature provided by NCBI and listed all other names in the alias field. In addition, we have provided a listing of both mouse and human paired systems as some families exist in both species whereas others are important in the study of either human or murine models of disease.
Table 1.
Mouse
| Family | Receptor | Cellular Expression | Chromosome location | Other names | Receptor characteristics | Cytoplasmic tyrosine motifs | Ligands(s) | Action | References |
|---|---|---|---|---|---|---|---|---|---|
| CD200r | Cd200r1 | Granulocytes, Monocytes, DCs, Macrophages, Mst cells, T cells, NKT cells, B cells | 16 | CD200R, Mox2r, OX2R | Type I transmembrane protein, 2 Ig-like domains | None | CD200 | Inhibition | Wright GJ. et al. 2000. Immunity. 13: 233 Wright GJ. et al. 2003. J Immunol. 171:3034 Vieites JM. et al. 2003. Gene. 311: 99 Hatherley D. et al. 2005. J Immunol.175: 2469 |
| CD200r | Cd200r3 | Basophils, Mast cells, Monocytes, DCs, B cells | 16 | mCD200RLb | Type I transmembrane protein, 2 Ig-like domains, Associates with DAP12 | None | Unknown | Activation | Voehringer D. et al. 2004. J Biol Chem. 279: 54117 Wright GJ. et al. 2003. J Immunol. 171: 3034 Hatherley D. et al. 2005. J Immunol.175: 2469 |
| CD200r | Cd200r4 | Macrophages, Monocytes, Granulocytes, Mast cells, DCs, NK, NKT, B cells | 16 | mCD200RLa, Cd200r2 | Type I transmembrane protein, 2 Ig-like domains, Associates with DAP12 | None | Unknown | Activation | Wright GJ. et al. 2003. J Immunol. 171: 3034 Hatherley D. et al. 2005. J Immunol.175: 2469 |
| CD300 | 4732429D16Rik | Granulocytes, Macrophages, Mast cells | 11 | CLM5, LMIR4, clm-5, RP23-331L12.3 | Type I transmembrane protein, 1 Ig-like domain, Associates with FcR γ chain | None | Unknown | Activation | Izawa K. et al. 2007. J Biol Chem. Apr 16. |
| CD300 | CD300a | Macrophages, Mast cells, DCs, Granulocytes, B cells, Eosinophils | 11 | LMIR1, Clm8, MMAC8, Pigr4, mcpir1, MAIR-Ia | Type I transmembrane, 1 Ig-like domain | ITIMs | Unknown | Inhibition | Munitz A. et al. 2006. J Allergy Clin Immunol. 118: 1082 Kumagai H. et al. 2003. Biochem Biophys Commun. 307: 719 Yotsumoto K. et al. 2003. J Exp Med. 198: 223 Bachelet I. et al. 2005. J Immunol. 175: 7989 |
| CD300 | Cd300b (AAY56360) | Myeloid cells | 11 | mIREM-3 | Type I transmembrane protein, 1 Ig-like domain, Associates with DAP12 and other unidentified molecules | None | Unknown | Activation | Martinez-Barriocanal A.and Sayos J. 2006. J Immunol. 177: 2819 |
| CD300 | Cd300c | Monocytes, Neutrophils, T cells, B cells | 11 | Clm6 | Type I transmembrane protein, Charged lysine residues in TM | None | Unknown | Activation? | Chung DH. et al. 2003. J Immunol. 171: 6541 |
| CD300 | CD300d | Macrophages, a subset of B cells, Mast cells | 11 | LMIR2, CLM4, DIgR1, Igsf7, Cd300c, MAIR-II | Type I transmembrane, Ig-like receptor, Associates with either DAP12, DAP10 or FcR γ chain | None | Unknown | Activation | Kumagai H. et al. 2003. Biochem Biophys Commun. 307: 719 Nakahashi C et al. 2007. J Immunol. 178: 765 Yotsumoto K. et al. 2003. J Exp Med. 198: 223 Turnbull IR. et al. 2007. Nature Rev. 7: 155 |
| CD300 | Cd300e | Myeloid cells | 11 | CLM2; TREM5; Cd300le | Type I transmembrane protein, Charged lysine residue in TM | None | Unknown | Activation? | Chung DH. et al. 2003. J Immunol. 171: 6541 |
| CD300 | Cd300lf | DCs | 11 | CLM1, CLIM1, Digr2, IREM1, Pigr3, IgSF13, F730004D16Rik, LMIR3 | Type I transmembrane protein, 1 Ig-like domain | 2 ITIMs | Unknown | Inhibition | Shi L. et al. 2006. Blood. 108: 2678 Álvarez-Errico D. et. al. 2007. J Immunol. 178: 808 Izawa K. et al. 2007. J Biol Chem. Apr 16. |
| Clecs | Clec4a2 | DCs, Neutrophils, B cells, Monocytes, Macrophages | 6 | DCIR, Dcir1, Clecsf6 | Type II trasmembrane protein, C-type lectin | ITIMs | Unknown | Inhibition | Bates EE. et al. 1999. J Immunol. 163: 1973 Kanazawa N. et al. 2004. Immunobiology. 209: 179 Flornes LM. et al. 2004. Immunogenetics. 56: 506 Kanazawa N. et al. 2002. J Invest. Dermatol. 118: 261 |
| Clecs | Clec4b1 | DCs, Monocytes, Macrophages, B cells | 6 | DCAR, Aplra2, Clec4b, mDcar2, DCARβ | Type II transmembrane protein, C-type lectin, Associates with FcR γ chain | None | Unknown | Activation | Kanazawa N. et al. 2004. Immunobiology. 209: 179 Kanazawa N. et al. 2003. J Biol Chem. 278: 32645 Robinson MJ. et al. 2006. Nature Immunol. 7: 1258 |
| Clecs | Clec4n | Monocytes, DCs, Polymorphonuclear cells | 6 | Clecsf10, dectin2 | Type II transmemrane protein, C-type lectin, FcR γ chain? | None | weak affinity to mannose | Activation | Aragane Y.et al. 2003. J Immunol. 171: 3801 Taylor PR. et al. 2005. Eur J Immunol. 35: 2163 Robinson MJ. et al. 2006. Nature Immunol. 7: 1258 Fernandes MJ. et al. 1999. Cancer Res. 59: 2709 |
| Clecs | Clec5a | Macrophages, Monocytes | 6 | Mdl1, Ly100, Clecsf5 | Type II transmembrane protein, C-type lectin, Associates with DAP12 | None | Unknown | Activation | Bakker A.B. et al. 1999. Proc Natl Acad Sci USA. 96: 9692 |
| Clecs | Clec7a | Macrophages, DCs, Monocytes, T cells, Polymorphonuclear cells | 6 | BGR, Clecsf12, β-GR | Type II trasmembrane protein, C-type lectin | ITAM-like motif (YxxL) | β-1,3-linked and β-1,6-linked glucans | Avtivation | Ariizumi K. et al. 2000. J Bio Chem. 275: 20157 |
| Klrb | Klrb1a | NK cells, NKT cells | 6 | Ly55a, NKR-P1A, Nkrp1-a, NKR-P1 2 | C-type lectin, Type II transmembrane protein, Believed to associate with FcR γ chain | YxxL motif | Clr | Activation or Inhibition | Ryan JC. et al. 2001. Immunol Rev. 181:126 Giorda et al. 1990. Science. 249: 1298 Plougastel et al. 2001. Immunogenetics 53: 592 |
| Klrb | Klrb1b | NK cells, NKT cells | 6 | Ly55b, NKR-P1B, Nkrp1-b, NKR-P1 34 | C type lectin, Type II transmembrane protein | ITIM | Unknown | Inhibition | Carlyle JR. et al. 2004. Proc Natl Acad Sci USA. 101: 3527 Trowsdale et al. 2001. Immunol Rev 181: 20 Ryan JC. et al. 2001. Immunol Rev. 181: 126 Giorda et al. 1990. Science. 249: 1298 Plougastel et al. 2001. Immunogenetics 53: 592 |
| Klrb | Klrb1c | NK cells, NKT cells | 6 | 117187 | C type lectin, Type II transmembrane protein, Associates with FcR γ chain | none | Unknown | Activation | Ryan JC. et al. 2001. Immunol Rev. 181: 126 Giorda et al. 1990. Science. 249: 1298 Plougastel et al. 2001. Immunogenetics 53: 592 |
| Klrb | Klrb1d | NK cells, NKT cells | 6 | Ly55d, Nkrp1d, NKR-P1D | C type lectin, Type II transmembrane protein | ITIM | Clr-b | Inhibition | Ryan JC. et al. 2001. Immunol Rev. 181: 126 Giorda et al. 1990. Science. 249: 1298 Plougastel et al. 2001. Immunogenetics 53: 592 Iizuka K. et al. 2003. Nat Immunol. 4: 801 |
| Klrb | Klrb1f | NK cells, CD8+ T cells, DCs | 6 | Nkrp1f, NKR-P1F, Nkrp1-f | C type lectin, Type II transmembrane protein, Charged arginine residue in TM | None | Clr-g | Activation? | Iizuka K. et al. 2003. Nat Immunol. 4: 801 Tian W. et al. 2005. Cell Immunol. 234: 39 Plougastel B. et al. 2001. Immunogenetics. 53: 209 |
| Ly49 | Ly49A | NK cells, NKT cells, some T cells | 6 | - | C-type lectins homodimers, Ly49A-like subfamily of Inhibitors | ITIM | Dd,k | Inhibition | Karlhofer et al. 1992. Nature 358: 66 Smith et al. 1994. J. Immunol. 153: 1068 Chan et al. 1989. J. Immunol. 142: 1727 Hanke et al. 1999. Immunity 11: 67 |
| Ly49 | Ly49B | Myeloid cells | 6 | - | C-type lectin; homodimers, Distantly related to inhibitory Ly49s | ITIM | Dd, Db, Dk, Kb, Kd | Inhibition | Wong et al. 1991. J. Immunol. 147: 1417 Scarpellino et al. 2007. J. Immunol. 178: 1277 Gays et al. 2006. J. Immunol. 177: 5840 |
| Ly49 | Ly49C | NK cells, NKT cells, some T cells | 6 | - | C-type lectins, Homodimers, Ly49C/I-like subfamily of inhibitors | ITIM | Db,d,k, Kd | Inhibition | Hanke et al. 1999. Immunity 11: 67 Brennan et al. 1996. J. Exp. Med. 184: 2085 Stoneman et al. 1995. J. Exp. Med. 182: 305 |
| Ly49 | Ly49D | NK cells | 6 | - | C-type lectins, Homodimers, Associates with DAP12, Ly49A-like subfamily of activators | None | Dd,r,sp | Activation | Ortaldo et al. 1999. J. Immunol. 163: 5269 Smith et al. 1994. J. Immunol. 153: 1068 Mason et al. 1996. J. Exp. Med. 184: 2119. |
| Ly49 | Ly49E | NK cells, NKT cells, some T cells | 6 | - | C-type lectins, Homodimers, Ly49C/I-like subfamily of inhibitors | ITIM | ? | Inhibition | Makrigiannis et al. 2001. J. Immunol. 166: 5034 Smith et al. 1994. J. Immunol. 153: 1068 Gays et al. 2005. J. Immunol. 175: 2938 Fraser et al. 2002. Eur. J. Immunol. 32: 868 |
| Ly49 | Ly49F | NK cells, NKT cells, some T cells | 6 | - | C-type lectins, Homodimers, Ly49C/I-like subfamily of inhibitors | ITIM | ? | Inhibition | Smith et al. 1994. J. Immunol. 153: 1068 Gays et al. 2005. J. Immunol. 175: 2938 |
| Ly49 | Ly49G | NK cells, NKT cells, some T cells | 6 | - | C-type lectins; homodimers, Ly49G-like subfamily of inhibitors | ITIM | Dd, Ld | Inhibition | Hanke et al. 1999. Immunity 11: 67 Mason et al. 1995. J. Exp. Med. 182: 293 Smith et al. 1994. J. Immunol. 153: 1068 |
| Ly49 | Ly49H | NK cells | 6 | - | C-type lectin, Homodimer, Associates with DAP12, Ly49C/I-like subfamily of activators | None | Db, and m157 in B6 mice | Activation | Brennan et al. 1996. J. Exp. Med. 184: 2085 Gosselin et al. 1999. J. Leuk. Biol. 66: 165 |
| Ly49 | Ly49I | NK cells, NKT cells, some T cells | 6 | - | C-type lectins, Homodimers, Ly49C/I-like subfamily of inhibitors | ITIM | Kd, Dk, Dd (in B6 mice), m157 (in 129 mice) | Inhibition | Hanke et al. 1999. Immunity 11: 67 Makrigiannis et al. 2001. J. Immunol. 166: 5034 |
| Ly49 | Ly49J | NK cells, NKT cells, some T cells | 6 | - | C-type lectins, Homodimers, Ly49C/I-like subfamily of inhibitors | ITIM | ? | Inhibition | McQueen et al. 1999. Immunogenetics 48: 174 |
| Ly49 | Ly49L | NK cells | 6 | - | C-type lectin, Homodimer, Associates with DAP12, Ly49C/I-like subfamily of activators | None | Unknown | Activation | McQueen et al. 1999. Immunogenetics 48: 174 Makrigiannis et al. 2000. J. Leuk. Biol. 68: 765 |
| Ly49 | Ly49O | NK cells, NKT cells, some T cells | 6 | - | C-type lectins homodimers, Ly49A-like subfamily of Inhibitors | ITIM | Db,d,k,Ld | Inhibition | Makrigiannis et al. 1999. J. Immunol. 163: 4931 |
| Ly49 | Ly49P | NK cells | 6 | - | C-type lectins, Homodimers, Associates with DAP12, Ly49A-like subfamily of activators | None | Dd,k(in NOD mouse strain) | Activation | Makrigiannis et al. 1999. J. Immunol. 163: 4931 Silver et al. 2000. J. Immunol. 165: 1771 |
| Ly49 | Ly49Q | pDC | 6 | - | C-type lectin; homodimers, Distantly related to inhibitory Ly49s | ITIM | Kb | Inhibition | Makrigiannis et al. 2002. Genomics 79: 437 Tai et al. 2007. Mol. Immunol. 44: 2638 Toyama-Sorimachi et al. 2005. J. Immunol. 174: 4621 Scarpellino et al. 2007. J. Immunol. 178: 1277 |
| Ly49 | Ly49R | NK cells | 6 | - | C-type lectins, Homodimers, Associates with DAP12, Ly49A-like subfamily of activators | None | Db,d,k,Ld | Activation | Makrigiannis et al. 2001. J. Immunol. 166: 5034 |
| Ly49 | Ly49S | NK cells, NKT cells, some T cells | 6 | - | C-type lectins, Homodimers, Ly49C/I-like subfamily of inhibitors | ITIM | ? | Inhibition | Makrigiannis et al. 2001. J. Immunol. 166: 5034 |
| Ly49 | Ly49T | NKT cells, some T cells | 6 | - | C-type lectins, Homodimers, Ly49G-like subfamily of inhibitors | ITIM | ? | Inhibition | Makrigiannis et al. 2001. J. Immunol. 166: 5034 |
| Ly49 | Ly49U | NK cells | 6 | - | C-type lectin, Homodimer, Associates with DAP12, Ly49C/I-like subfamily of activators | None | Db | Activation | Makrigiannis et al. 2001. J. Immunol. 166: 5034 |
| Ly49 | Ly49V | NK cells, NKT cells, some T cells | 6 | - | C-type lectins homodimers, Ly49A-like subfamily of Inhibitors | ITIM | Dd, b,k,Kb,d,kLd | Inhibition | Makrigiannis et al. 2001. J. Immunol. 166: 5034 |
| Ly49 | Ly49W | — | 6 | - | C-type lectin, Homodimer, Associates with DAP12, Ly49G-like subfamily of activators | Dd, k (in NOD mouse strain) | Unknown | Activation | Silver et al. 2001. J. Immunol. 166: 2333 |
| NKG2 | NKG2A/B | NK cells, Activated CD8+, NKT cells | 6 | CD159A; Klrc1 | C-type lectin, Heterodimerizes with CD94 | 2 ITIMs | Qa-1(b) | Inhibition | Salcedo et al. 1998. Eur J Immunol. 28: 4356 Vance et al. 1998. J Exp Med. 188: 1841 Smith et al. 2001. Immunol Rev. 181: 115 Barten et al. 2001. Trends Immunol. 22: 52 Lohwasser et al. 1999. Eur J Immunol. 29: 755 |
| NKG2 | NKG2C | NK cells, Activated CD8+ cells, NKT cells | 6 | Klrc2 | C-type lectin, Heterodimerizes with CD94, Associates with DAP12 | None | Qa-1(b) | Activation | Salcedo et al. 1998. Eur J Immunol. 28: 4356 Vance et al. 1999. J Exp Med. 190: 1801 Smith et al. 2001. Immunol Rev. 181: 115 Barten et al. 2001. Trends Immunol. 22: 52 Lohwasser et al. 1999. Eur J Immunol. 29: 755 |
| NKG2 | NKG2D | NK cells, Activated CD8+, LPS-activated macrophages | 6 | None | C-type lectin, Associates with DAP10 | None | H60, RAE-1 | Activation | Ho et al. 1998. Proc Natl Acad Sci USA. 95: 6320 Smith et al. 2001. Immunol Rev. 181: 115 Cerwenka et al. 2000. Immunity. 12: 721 Lanier LL. 2003. Curr. Opin. Immunol. 15: 308 |
| NKG2 | NKG2D-S (short form) | NK cells, T | 6 | None | C-type lectin, Associates with DAP12 and DAP10 | None | H60, RAE-1 | Activation | Gilfillan S et al. 2002. Nature Immunol. 3: 1150 Diefenbach A et al. 2002. Nature Immunol. 3: 1142 Lanier LL. 2003. Curr Opin Immunol. 15: 308 |
| NKG2 | NKG2E | Activated CD8+ cells | 6 | Klrc3 | C-type lectin, Heterodimerizes with CD94, Associates with DAP12 | None | Qa-1(b) | Activation | Vance RE. et al. 1999. J Exp Med. 190: 1801 O'Callaghan CA. et al. 2000. Microbes Infect. 2: 371 |
| PILR | Pilra | Granulocytes, Macrophages | 5 | FDF03 | 1 Ig-like domain | ITIM | CD99 like molecules | Inhibition | Fournier NJ. et al. 2000. Immunol. 165: 1197 Shiratori I. et al. 2004. J Exp Med. 199: 525 |
| PILR | Pilrb1 | NK cells, Macrophages, DCs, Granulocytes | 5 | Fdact, Pilrb, FDFACT | 1 Ig-like domain, Associates with DAP12 | None | CD99 like molecules | Activation | Fournier NJ. et al. 2000. Immunol. 165: 1197 Shiratori I. et al. 2004. J Exp Med. 199: 525 |
| PIR | Lilrb3 | Mast cells, Macrophages, B cells, Granulocytes, DCs, Neurons | 7 | Gp91, Lilrb3, Pirb | 6 Ig-like domains | 1 ITIM and 2 ITSMs | H-2Kb, 2Kk, 2Kd, 2Dd, 2Ld, HLA-G | Inhibition | Takai T. 2005. Immunology. 115: 433 Chen CC. et al. 2002. Immunol Res. 26: 191 Liang S. et al. 2002. Eur J Immunol. 32: 2418 Ujike A et al. 2002. Nat Immunol. 3: 542 Syken J. et al. 2006. Science. 313: 1795 |
| PIR | Pira1 | Mast cells, Macrophages, DCs, Granulocytes | 7 | Pir, 6M21, Ly89, PIR-A1 | 6 Ig-like domains, Associates with FcR γ chain | None | H-2 molecules, HLA-G | Activation | Kubagawa H. et al. 1997. Proc Natl Acad Sci USA. 94: 5261 Takai T. 2005. Immunology. 115: 433 Colonna M. 2003. Nature Rev Immunol. 3: 1 |
| Siglec | Siglec-3 | Monocytes, Macrophages | 7 | Cd33, gp67 | Type I transmembrane protein, 2 Ig-like domains | ITIM and ITSM | Sialic acids | Inhibition | Brinkman-Van der Linden EC. et al. 2003. Mol Cell Biol. 23: 4199 Crocker PR. and Varki A. 2001. Immunology. 103: 137 Crocker PR. et al. 2002. Curr Op Structure Biol. 12: 609 Crocker PR. et al. 2007. Nature Rev Immunol. 7: 255 |
| Siglec | Siglece | Neutrophils, Monocytes, Macrophages, Eosinophils, NK cells, DCs, Some B cells | 7 | Cd170, Siglec5, Siglec9, Siglecl1, mSiglec-E | Type I transmembrane protein, 3 Ig-like domains | ITIM and ITSM | Sialic acids | Inhibition | Aizawa H. et al. 2003. Genomics. 82: 521 Zhang JQ. 2004. Eur. J. Immunol. 34: 1175 Yu Z. et al. 2001. Biochem J. 353: 483 Crocker PR. et al. 2007. Nature Rev Immunol. 7: 255 |
| Siglec | Siglecf | Eosinophils | 7 | Siglec5; mSiglec-F | Type I transmembrane protein, 4 Ig-like domains | ITIM and ITSM | Sialic acids (α2,3-linkages > α2,6-linkages) | Inhibition | Zhang M. et al. 2007. Blood. 109: 4280 Aizawa H. et al. 2003. Genomics. 82: 521 Angata T. et al. 2001. J Biol Chem. 276: 45128 Crocker PR. et al. 2007. Nature Rev Immunol. 7: 255 |
| Siglec | Siglecg | Eosinophils, B cells | 7 | Siglec-G; Siglec10; mSiglec-G | Type I transmembrane protein, 5 Ig-like domains | ITIM and ITSM | Sialic acids | Inhibition | Crocker PR. et al. 2007. Nature Rev Immunol. 7: 255 Aizawa H. et al. 2003. Genomics. 82: 521 |
| Siglec | Siglech | Plasmacytoid DCs | 7 | Siglec-H | Type I transmembrane protein, 2 Ig-like domains, Associates with DAP12 | None | Sialic acids | Inhibition of IFNα pathway | Blasius AL. et al. 2006. Blood. 107: 2474 Blasius AL. et al. 2006. Trends Immunol. 27: 255 Zhang J. et al. 2006. Blood. 107: 3600 Crocker PR. et al. 2007. Nature Rev Immunol. 7: 255 |
| SIRP | Sirpα | Myeloid cells, Neurons | 2 | Sirp-α, P84, SIRP, SHP-1, CD172a, Ptpns1, SHPS-1, Bit | 3 Ig-like domains | ITIMs | CD47, Surfactant proteins A and D | Inhibition | Sano S. et al. 1997. FEBS Lett. 411: 327 Barclay AN. and Brown M.H. 2006. Nature Rev Immunol. 6: 457 |
| SIRP | Sirpβ1 | Macrophages, Neutrophils | 3 | Sirpβ, SIRP-β | 3 Ig-like domains, Associates with DAP12 | None | Unknown | Activation | Lahoud MH. et al. 2006. J Immunol. 177: 372 Hayashi A. et al. 2004. J Biol Chem. 279: 29450 Barclay AN. and Brown M.H. 2006. Nature Rev Immunol. 6: 457 |
| TREM | Trem1 | A subset of monocytes and macrophages, Neutrophils, Granulocytes | 17 | - | Type I transmembrane protein, 1 Ig-like domain, Associates with DAP12 | None | Unknown | Activation | Kelker MS. Et al. 2004. J Mol Biol. 344: 1175 Murakami Y. et al. 2007. J Immunol. 178: 1144 Chung DH. et al. 2002. Eur J Immunol. 32: 59 Bouchon A. et al. 2001. Nature. 410: 1103 |
| TREM | Trem2 | Activated macrophages, DCs, Osteoclasts, Microglia | 17 | Trem2a, Trem2b, Trem2c | Type I transmembrane protein, 1 Ig-like domain, Associates with DAP12 | None | Unknown | Activation/Inhibition | Daws MR. et al. 2003. J. Immunol. 171: 594 Turnbull IR et al. 2006. J Immunol. 177: 3520 Hamerman JA. et al. 2006. J Immunol. 177: 2051 Humphrey MB. et al. 2006. J Bone Miner Res. 21: 237 |
| TREM | Trem3 | Myeloid cells | 17 | - | Type I transmembrane protein, 1 Ig-like domain, Associates with DAP12 | None | Unknown | Activation | Chung DH. et al. 2002. Eur J Immunol. 32: 59 |
Table 2.
Human
| Family | Receptor | Cellular Expression | Chromosome location | Other names | Receptor characteristics | Cytoplasmic tyrosine motifs | Ligands(s) | Action | References |
|---|---|---|---|---|---|---|---|---|---|
| CD200R | CD200R1 | Macrophages, Neutrophils, Monocytes, DCs, Mast cells, T cells, NKT cells, B cells | 3 | OX2R, MOX2R, CD200R, HCRTR2 | Type I transmembrane protein, 2 Ig-like domains | None | CD200 | Inhibition | Minas K. et al. 2006. Crit Rev Immunol. 26: 213 Wright GJ et al. 2003. J Immunol. 171: 3034 |
| CD200R | CD200R2 | Basophils, Mast cells | 3 | CD200RLa | Type I transmembrane protein, 2 Ig-like domain, Associates with DAP12 | None | Unknown | Activation | Wright GJ. et al. 2003. J Immunol. 171: 3034 Voehringer D. 2004. J Biol Chem. 279: 54117 |
| CD300 | CD300A | Eosinophils, Mast cells | 17 | IRC1, IRC2, IRp60, IGSF12, CMRF35H, CMRF35H9 | Type I transmembrane protein, 1 Ig-like domain, | 3 ITIMs | Unknown | Inhibition | Munitz A. et al. 2006. Blood. 107: 1996 Bachelet I. et al. 2005. J Immunol. 175: 7989 |
| CD300 | CD300C | Monocytes, Neutrophils, T cells, B cells | 17 | CMRF35A1, CMRF35A, CMRF35, IGSF16 | Type I trasnmembrane protein, 1 Ig-like domain, Adaptor molecule unknown | None | Unknown | Activation | Clark GL. et al. 2001. Tissue Antigens. 57: 415 |
| CD300 | CD300E | Monocytes, Myeloid DCs, Macrophages | 17 | CLM2, IREM2, CD300LE | Type I transmembrane protein, 1 Ig-like domain, Associates with DAP12 | None | Unknown | Activation | Aguilar H. et al. 2004. J Immunol. 173: 6703 Clark GJ. et al. 2007. J Immunother. 30: 303 |
| CD300 | CD300LB | Myeloid cells | 17 | CLM7, IREM3, TREM5 | Type I transmembrane protein, 1 Ig-like domain, Associates with DAP12 and unidentified molecules | Tyrosine-based motif | Unknown | Activation | Martinez-Barriocanal A.and Sayos J. 2006. J Immunol. 177: 2819 |
| CD300 | CD300LF | Myeloid cells | 17 | CLM1, NKIR, IREM1, CD300f, IgSF13 | Type I transmembrane protein, 1 Ig-like domain | 2 ITIMs | Unknown | Inhibition | Marquez J.A. et al. 2007. J Mol Biol. 367: 310 Alvarez-Errico D. et al. 2007. J Immunol. 178: 808 Alvarez-Errico D. et al. 2004. Eur J Immunol. 34: 3690 |
| CLEC | CLEC12A | Monocytes, Macrophages, DCs, Granulocytes | 12 | CLL1, MICL, CLL-1, DCAL-2 | Type II transmembrane protein, C-type lectin | 1 ITIM | Unknown | Inhibition | Marshall AS. et al. 2004. J Biol Chem. 279: 14792 Bakker AB. et al. 2004 Cancer Res. 64: 8443 Robinson MJ. et al. 2006. Nat Immunol. 7: 1258 |
| CLEC | CLEC2B | Macrophages, Granulocytes, Monocytes | 12 | AICL, IFNRG1, CLECSF2 | Type II trasmembrane protein, C-type lectin | ? | NKp80 | Activation | Welte S. et al. 2006. Nature Immunol. 7: 1334 |
| CLEC | CLEC2D | NK cells | 12 | LLT1, OCIL, CLAX | Type II transmembrane protein, C-type lectin | ? | KLRB1 (NKR-P1A) | Activation | Boles KS. et al. 1999. Immunogenetics. 50: 1 Lebbink RJ. and Meyaard L. 2007. Mol Immunol. 44: 2153 Aldemir H. et al. 2005. J Immunol. 176: 7791 Rosen DB. Et al. 2005. J immunol. 176: 7796 Mathew PA. et al. 2004. Mol Immunol. 40: 1157 |
| CLEC | CLEC4A | DCs, Neutrophils, B cells, Monocytes, Macrophages | 12 | DCIR, LLI, DDB27, CLECSF6, HDCGC13P | Type II trasmembrane protein, C-type lectin | 1 ITIM | Unknown | Inhibition | Kanazawa N. et al. 2004. Immunobiology. 209: 179 Bates EE. et al. 1999. J Immunol. 163: 1973 |
| CLEC | CLEC4C | Plasmacytoid DCs, Monocytes, Macrophages, Neutrophils | 12 | DLEC, HECL, BDCA2, CD303, CLECSF7, CLECSF11 | Type II trasmembrane protein, C-type lectin, Adaptor molecules unknown | None | Unknown | Activation or Inhibition | Dzionek A. et al. 2001. J Exp Med. 194: 1823 Dzionek A. et. al. 2002. Hum Immunol. 63: 1133 Kanazawa N. et al. 2004. Immunobiology. 209: 179 |
| CLEC | CLEC6A | Monocytes, Macrophages, Neutrophils, DCs, B cells, Activated CD4+ T cells | 12 | CLECSF10, dectin-2 | Type II trasmembrane protein, C-type lectin, Associates with Fc γ receptor | None | Hyphal components of some fungi | Activation | Sato et al. 2006. J Biol Chem. 281: 38854 Gavino AC. et al. 2005. Exp Dermatol. 14: 281 Robinson MJ. et al. 2006. Nat Immunol. 7: 1258 Kanazawa N. et al. 2004. Immunobiology. 209: 179 |
| CLEC | CLEC7A | Macrophages, DCs, Monocytes, T cells, B cells, Eosinophils, Polymorphonuclear cells | 12 | DECTIN1, CLECSF12, BGR | Type II trasmembrane protein, C-type lectin | ITAM-like motif (YxxL) | β-1,3-linked and β-1,6-linked glucans | Activation | Gersuk GM. et al. 2006. J Immunol. 176: 3717 Underhill DM. et al. 2005. Blood. 106: 2543 Robinson MJ. et al. 2006. Nat Immunol. 7: 1258 Lee MS. et al. 2007. Mol Cells. 23: 1 Willnent JA. et al. 2005. Eur J Immunol. 35: 1539 |
| CLEC | KLRB1 | NK cells, NKT cells, T cells | 12 | NKR-P1A, NKR-P1, NKR, CD161, CLEC5B | Type II trasmembrane protein, C-type lectin | ? | CLEC2D (LLT1) | Activation or Inhibition | Lanier LL. et al. 1994. J Immunol. 153: 2417 Pozp D. et al. 2006. J Immunol. 176: 2397 Lebbink RJ. and Meyaard L. 2007. Mol Immunol. 44: 2153 Aldemir H. et al. 2005. J Immunol. 176. 7791 Rosen DB. Et al. 2005. J immunol. 176: 7796 |
| CLEC | KLRF1 | NK cells | 12 | NKp80, CLEC5C | Type II transmembrane protein, C-type lectin, Homodimer, Lack of charged residues | ? | CLEC2B (AICL) | Activation | Welte S. et al. 2006. Nature Immunol. 7: 1334 |
| CLEC | KLRG1 | Some NK cells and T cells | 12 | 2F1, MAFA, MAFA-L, CLEC15A, MAFA-2F1, MGC13600 | Type II transmembrane protein, C-type lectin | 1 ITIM | Cadherins | Inhibition | Lebbink RJ. and Meyaard L. 2007. Mol Immunol. 44: 2153 Ito M. et al. 2006. J Exp Med. 203: 289 Grundermann C. et al. 2006. J Immunol. 176: 1311 |
| KIR | KIR2DL1 | NK, NKT cells, T cells | 19 | NKAT, 47.11, CL-42, NKAT1, p58.1, CD158a, KIR-K3, KIR-K9, KIR221, KIR-K64, KIR-K65 | Type I transmembrane protein, 2 Ig-like domains | 2 ITIMs | HLA-C N77/K80 | Inhibition | Stewart C.A. et al. 2005. Proc Natl Acad Sci USA. 102: 13224 Colonna M. and Samaridis J. Science. 1995. 268: 405 Wagtmann N. et al. 1995. Immunity. 2: 439 Boyington JC. et al. 2001. Mol Immunol 38: 1007 Lanier LL. et al. Annu Rev Immunol 2005. 23: 225 Parham P. 2005. Nature Rev Immunol. 5: 201 |
| KIR | KIR2DL2 | NK cells, NKT cells, T cells | 19 | NKAT6, p58.2, CD158b, CD158B1 | Type I transmembrane protein, 2 Ig-like domains | 2 ITIMs | HLA-C S77/N80 | Inhibition | Boyington JC. et al. 2001. Mol Immunol 38: 1007 Lanier LL. et al. Annu Rev Immunol. 2005. 23: 225 Parham P. 2005. Nature Rev Immunol. 5: 201 |
| KIR | KIR2DL3 | NK, NKT cells, T cells | 19 | p58, CL-6, NKAT, GL183, NKAT2, CD158b, NKAT2A, NKAT2B, NKR-K7, CD158B2, KIR-K15, KIR-K7c, p58 KIR, KIR-023GB | Type I transmembrane protein, 2 Ig-like domains | 2 ITIMs | HLA-C S77/N80 | Inhibition | Colonna M. and Samaridis J. Science. 1995. 268: 405 Lanier LL. et al. Annu Rev Immunol. 2005. 23: 225 Parham P. 2005. Nature Rev Immunol. 5: 201 |
| KIR | KIR2DL4 | CD56high NK cells and IL-2 activated NK cells | 19 | G9P, CD158D, KIR103, KIR103AS | Type I transmembrane protein, 3 Ig-like domains, Associates with FcR γ chain, Recruits SHP-2 | ITIM | HLA-G | Activation/Inhibition | Faure M. and Long EO. 2002. J Immuno. 168: 6208 Goodridge JP. et al. 2003. J Immunol. 171: 1768 Rajagopalan S. et al. 2001. 167: 1877 Lanier LL. et al. Annu Rev Immunol. 2005. 23: 225 Kikuchi-Maki A. et al. 2003. J Immunol. 171: 3415 |
| KIR | KIR2DL5A | NK cells, T cells | 19 | CD158F, KIR2DL5, KIR2DL5.1, KIR2DL5.3 | Type I transmembrane protein, 3 Ig-like domains | 2 ITIMs | Unknown | Inhibition | Gomez-Lozano N. et al. 2002. Immunogenetics. 54: 314 Estefania E. et al. 2007. J Immunol. 178: 4402 Yusa S. et al. 2004. J Immunol. 172: 7385 Lanier LL. et al. Annu Rev Immunol. 2005. 23: 225 |
| KIR | KIR2DL5B | NK cells, T cells | 19 | KIR2DL5, KIR2DL5.2, KIR2DLX | Type I transmembrane protein, 3 Ig-like domains | 2 ITIMs | Unknown | Inhibition | Gomez-Lozano N. et al. 2002. Immunogenetics. 54: 314 Estefania E. et al. 2007. J Immunol. 178: 4402 Yusa S. et al. 2004. J Immunol. 172: 7385 Lanier LL. et al. Annu Rev Immunol. 2005. 23: 225 |
| KIR | KIR2DS1 | NK cells | 19 | p50.1; CD158H; CD158a | Type I transmembrane protein, 2 Ig-like domains, Associates with DAP12 | None | HLA-C weakly, Peptide specificity is similar to KIR2DL1 | Activation | Lanier LL. et al. Annu Rev Immunol. 2005. 23: 225 Lanier LL. et al. 1998. Nature. 391: 1998 Stewart C.A. et al. 2005. Proc Natl Acad Sci USA. 102: 13224 |
| KIR | KIR2DS2 | NK cells | 19 | NKAT5, CD158J, CD158b, p58 KIR | Type I transmembrane protein, 2 Ig-like domains, Associates with DAP12 | None | Very low affinity to HLA-C S77/N80 with uncertainty | Activation | Snyder MR. et al. 2004. J Immunol 173: 3725 Saulquin X. et al. 2003. J Exp Med. 197: 933 Lanier LL. et al. 1998. Nature. 391: 1998 Stewart CA. et al. 2005. Proc Natl Acad Sci USA. 102: 13224 |
| KIR | KIR2DS3 | NK cells | 19 | NKAT7 | Type I transmembrane protein, 2 Ig-like domains, Associates with DAP12 | None | Unknown | Activation | Becker S. et al. 2003. Hum Immunol 64: 183 Lanier LL. et al. 1998. Nature. 391: 1998 Lanier LL. et al. Annu Rev Immunol. 2005. 23: 225 |
| KIR | KIR2DS4 | NK cells, NKT cells | 19 | KKA3, KIR1D, NKAT8, CD158I, KIR412 | Type I transmembrane protein, 2 Ig-like domains, Associates with DAP12 | None | Non-MHC class I protein | Activation | Lanier L.L. et al. Annu Rev Immunol. 2005. 23: 225 Katz et al. 2004. J Immunol. 173: 1819 |
| KIR | KIR2DS5 | NK cells | 19 | NKAT9, CD158G | Type I transmembrane protein, 2 Ig-like domains, Associates with DAP12 | None | Unknown | Activation | Becker S. et al. 2003. Hum Immunol. 64: 183 Lanier LL. et al. Annu Rev Immunol. 2005. 23: 225 |
| KIR | KIR3DL1 | NK cells, NKT cells, T cells | 19 | KIR, CL-2, NKB1, AMB11, CL-11, NKAT3, NKB1B, KIR-G1, NKAT10, CD158E1, CD158E2, KIR3DS1, CD158E1/2 | Type I transmembrane protein, 3 Ig-like domains | 2 ITIMs | HLA-A-Bw4, HLA-B-Bw4 | Inhibition | Lanier LL. et al. Annu Rev Immunol. 2005. 23: 225 Stewart CA. et al. 2003. J Immunol. 170: 6073 Yawata M. et al. 2006. J Exp Med. 203: 633 Carr WH. Et al. 2005. J Immunol. 175: 5222 Stewart-Jones GBE. et al. 2005. Eur J Immunol. 35: 341 |
| KIR | KIR3DL2 | NK cells, T cells | 19 | p140, NKAT4, CD158K, NKAT4B | Type I transmembrane protein, 3 Ig-like domains | 2 ITIMs | HLA-A | Inhibition | Chan HW. et al. 2003. J Exp Med. 197: 245 Meenagh A. et al. 2004. Tissue Antigens. 64: 226 Lanier LL. et al. Annu Rev Immunol. 2005. 23: 225 |
| KIR | KIR3DL3 | NK cells, T cells | 19 | KIR44, KIRC1, CD158Z, KIR3DL7, KIR3DL3var | Type I transmembrane protein, 3 Ig-like domains | 2 ITIMs | Unknown | Inhibition | Jones DC. et al. 2006. Immunogenetics. 58: 614 Trundley AE. et al. 2006. Immunogenetics. 57: 904 Long EO. et al. 2001. Immunol. Rev. 181: 223 Lanier LL. et al. Annu Rev Immunol. 2005. 23: 225 |
| KIR | KIR3DS1 | NK cells, NKT cells, T cells | 19 | NKAT10, CD158E2 | Type I transmembrane protein, 3 Ig-like domains, Associates with DAP12 | None | Unknown | Activation | Pascal V. et al. 2007. J Immunol. in press Lanier LL. et al. Annu Rev Immunol 2005. 23: 225 O'Connor GM. 2007. J Immunol. 178: 235 Carr WH. 2007. J Immunol. 178: 647 Trundley A. et al. 2007. Eur J Imunol. 3: 780 |
| LILR | LILRA1 | Monocytes | 19 | LIR6, CD85I | 4 Ig-like domains, Associates with FcR γ chain | None | Recognize classical and b2m free heavy chain form of HLA-B27 | Activation | Borges L. et al. 1997. J. Immunol. 159: 5192 Colonna M. 2003. Nature Rev Immunol. 3:1 Allen RL. et al. 2001. J Immunol. 167: 5543 Tedla N. et al. 2003. Proc Natl Acad Sci USA. 100: 1174 Brown D. et al. 2004. Tissue Antigens. 64: 215 |
| LILR | LILRA2 | Eosinophils, Basophils, Monocytes, Neutrophils | 19 | LIR7, ILT1, CD85h | 4 Ig-like domains, Associates with FcR γ chain | None | MHC class I? | Activation | Colonna M. 2003. Nature Rev Immunol. 3: 1 Tedla N. et al. 2003. Proc Natl Acad Sci USA. 100: 1174 Sloane DE. et al. 2004. Blood. 104: 2832 Brown D. et al. 2004. Tissue Antigens. 64: 215 |
| LILR | LILRA3 | Soluble molecules | 19 | e3, HM31, HM43, ILT6, LIR4, CD85E, LIR-4 | 4 Ig-like domains | None | MHC class I? | Activation | Colonna M. 2003. Nature Rev Immunol. 3: 1 |
| LILR | LILRA4 | Plasmacytoid DCs | 19 | ILT7, CD85g | 4 Ig-like domains, Associates with FcR γ chain | None | Unknown | Activation or Inhibition | Brown D. et al. 2004. Tissue Antigens. 64: 215 Cao W. et al. 2006. J Exp Med. 203: 1399 |
| LILR | LILRA5 | Neutrophils, Monocytes, Myelomonocytic cells | 19 | CD85, LIR9, CD85F, ILT11, LILRB7 | 2 Ig-like domains, Associates with FcR γ chain, Extracellular domain can be a soluble molecule | None | Unknown Do not bind to classical and nonclassical MHC class I | Activation | Borges L. et al. 2003. Blood. 101: 1484 Brown D. et al. 2004. Tissue Antigens. 64: 215 Shiroishi M. et al. 2006. J Bio Chem. 281: 19536 |
| LILR | LILRB1 | Monocytes, DCs, NK cells, T cells, B cells, Neutrophils, Eosinophils | 19 | LIR1, ILT2, CD85, CD85j | 4 Ig-like domains | 4 ITIMs | MHC class I molecules (Preferentially HLA-G), HCMV UL18 | Inhibition | Tedla N. et al. 2003. Proc Natl Acad Sci USA. 100: 1174 Colonna M. 2003. Nature Rev Immunol. 3: 1 Shiroishi M. et al. 2006. Prod Natl Acd Sci USA. 103: 16412 Brown D. et al. 2004. Tissue Antigens. 64: 215 Cosman D. et al. 1997. J Immunol. 7: 273 |
| LILR | LILRB2 | Myelomonocytic lineage, Eosinophils, Monocytes | 19 | CD85D, ILT4, LIR-2, LIR2, MIR-10, MIR10 | 4 Ig-like domains | 3 ITIMs | Recognize many MHC class I molecules, Preferentially HLA-G, free heavy chains of HLA-B27, HCMV UL18 | Inhibition | Tedla N. et al. 2003. Proc Natl Acad Sci USA. 100: 1174 Colonna M. 2003. Nature Rev Immunol. 3: 1 Shiroishi M. et al. 2006. Prod Natl Acd Sci USA. 103: 16412 Allen RL. et al. 2001. J Immunol. 167: 5543 Brown D. et al. 2004. Tissue Antigens. 64: 215 |
| LILR | LILRB3 | Eosinophils, Basophils, Monocytes, Neutrophils | 19 | HL9, ILT5, LIR3, CD85A | 4 Ig-like domains | 4 ITIMs | Unknown, Does not bind to B27 | Inhibition | Tedla N. et al. 2003. Proc Natl Acad Sci USA. 100: 1174 Colonna M. 2003. Nature Rev Immunol. 3: 1 Sloane DE. et al. 2004. Blood. 104: 2832 Brown D. et al. 2004. Tissue Antigens. 64: 215 |
| LILR | LILRB4 | Monocytes | 19 | LILR5, LIR5, ILT3, CD85K | 2 Ig-like domains | 3 ITIMs | Unknown, Does not bind to B27 | Inhibition | Colonna M. 2003. Nature Rev Immunol. 3:1 Tedla N. et al. 2003. Proc Natl Acad Sci USA. 100: 1174 Brown D. et al. 2004. Tissue Antigens. 64: 215 Vlad G. et al. 2006. Int Immunopharmacol. 6: 1889 |
| LILR | LILRB5 | Monocytes | 19 | LILR8, CD85C | 4 Ig-like domains | 2 ITIMs | Unknown | Inhibition | Colonna M. 2003. Nature Rev Immunol. 3: 1 Tedla N. et al. 2003. Proc Natl Acad Sci USA. 100: 1174 Brown D. et al. 2004. Tissue Antigens. 64: 215 Borges L. et al. 1997. J Immuno. 159: 5192 |
| NKG2 | KLRC1 | NK, Activated CD8+, NKT cells | 12 | NKG2, NKG2A, CD159A | Type II trasmemrbane protein, C type lectin, Heterodimerizes with CD94 | 2 ITIMs | HLA-E | Inhibition | Lanier LL. et al. Annu Rev Immunol 2005. 23: 225 Kabat A. et al. 2002. J. Immunol. 169: 1948 Michaelsson J. et al. 2002. J Exp Med. 196: 1403 Brett KK. 2005. J Immunol. 174: 2878 Houchins JP. et al. 1991. J Exp Med. 173: 1017 |
| NKG2 | KLRC2 | NK, Activated CD8+ cells, NKT cells | 12 | NKG2C, CD159c | Type II transmembrane protein, C type lectin, Heterodimerizes with CD94, associates with DAP12 | None | HLA-E | Activation | Lanier LL. et al. Annu Rev Immunol. 2005. 23: 225 Hikami K. et al. 2003. Genes Immun. 4: 160 Houchins JP. et al. 1991. J Exp Med. 173: 1017 Brett KK. 2005. J Immunol. 174: 2878 |
| NKG2 | KLRC3 | NK, Activated CD8+ cells | 12 | NKG2E | Type II transmembrane protein, C type lectin, Heterodimerizes with CD94, Associates with DAP12 | None | HLA-E | Activation | Lanier LL et al. 1998. Immunity. 8: 693 Brett KK. 2005. J Immunol. 174: 2878 Adamkiewicz TV. et al. 1994. Immunogenetics. 39: 218 Glienke J. et al. 1998. Immunogenetics. 48: 163 |
| NKG2 | KLRK1 | NK, CD8+ T, γδT, LPS-activated macrophages | 12 | CD314, NKG2D, KLR | Type II trasnemembrane protein, C type lectin, Homodimer, Associates with DAP10 | None | MICA/MICB, ULBP | Activation | Raulet DH. 2003. Nat Rev Immunol 3: 781 Lanier LL. 2003. Curr Opin Immunol. 15: 308 Groh V. et al. 2002. Nature. 419: 734 Sutherland CL. et al. 2002. J Immunol. 168: 671 |
| PILR | PILRA | Monocytes, Macrophages, Granulocytes | 7 | PILRα, FDF03 | 1 Ig-like domain | ITIMs | CD99 related molecule | Inhibition | Mousseau DD. et al. 2000. J Biol Chem. 275: 4467 Koga T. et al. 2004. Nature. 428: 758 Fournier N. et al. 2000. J Immunol. 165: 1197 |
| PILR | PILRB | Leukocytes | 7 | PILRβ, FDFACT1, FDFACT2 | 1 Ig-like domain, Charged lysine residue in TM | None | Unknown | Activation | Mousseau DD. et al. 2000. J Biol Chem. 275: 4467 Fournier N. et al. 2000. J Immunol. 165: 1197 |
| SIGLEC | SIGLEC10 | Eosinophils, Monocytes, NK cells, Neutrophils, B cells | 19 | SLG2, PRO940 | Type I transmembrane protein, 5 Ig like-domains | ITIM and ITSM | Sialic acids (α2,3 linkages = α2,6-linkages) | Inhibition | Li N. et al. 2001. J Biol Chem. 276: 28106 Clark HF. et al. 2003. Genome Res. 13: 2265 Crocker PR. et al. 2007. Nature Rev Immunol. 7: 255 |
| SIGLEC | SIGLEC11 | Macrophages, Microglia | 19 | - | Type I transmembrane protein, 5 Ig-like domains | ITIM and ITSM | Sialic acids (α2,8-linkages) | Inhibition | Hayakawa T. et al. 2005. Science. 309: 1693 Angata T et al. 2002. J Biol Chem. 277: 24466 Clark HF. et al. 2003. Genome Res. 13: 2265 Crocker PR. et al. 2007. Nature Rev Immunol. 7: 255 |
| SIGLEC | SIGLEC14 | Hematopoietic cells | 19 | - | 3 Ig-like domains, Associates with DAP12 | None | Sialic acids | Activation | Angata T. et al. 2006. FASEB J. 20: 1964 Crocker PR. et al. 2007. Nature Rev Immunol. 7: 255 |
| SIGLEC | SIGLEC3 | Myeloid progenitor cells, Monocytes, Activated T cells, Activated NK cells | 19 | CD33, p67, FLJ00391 | Type I transmembrane protein, 2 Ig-like domains | ITIM and ITSM | Sialic acids (α2,6-linkages > α2,3-linkages) | Inhibition | Hernandez-Caselles T. et al. 2006. J Leukoc Biol 79: 46 Crocker PR. et al. 2002. Curr Op Structure Biol. 12: 609 Crocker PR. et al. 2007. Nature Rev Immunol. 7: 255 |
| SIGLEC | SIGLEC5 | Neutrophils, Macrophages, Monocytes, Basophils, B cells | 19 | CD170, OBBP2, CD33L2, OB-BP2 | Type I transmembrane protein, 4 Ig-like domains | ITIM and ITSM | Sialic acid (α2,3-linkages = α2,6-linkages > α2,8-linkages) | Inhibition | Angata T. et al. 2006. FASEB J. 20: 1964 Avril T. et al. 2005. J Biol Chem. 280: 19843 Erickson-Miller CL. et al. 2003. Exp Hematol. 31: 382 Ghannadan M. et al. 2002. Int Arch Allergy Immunol. 127: 299 Crocker PR. et al. 2007. Nature Rev Immunol. 7: 255 |
| SIGLEC | SIGLEC6 | Neutrophils, B cells, Placental trophoblasts | 19 | CD33L, OBBP1, CD33L1, CDw327 | Type I transmembrane protein, 3 Ig-like domains | ITIM and ITSM | Sialyl Tn antigen | Inhibition | Patel N. et al. 1999. J Biol Chem. 274: 22729 Crocker PR. et al. 2007. Nature Rev Immunol. 7: 255 |
| SIGLEC | SIGLEC7 | Granulocytes, Monocytes, NK cells, CD8+ T cells | 19 | p75, QA79, AIRM1, CDw328, D-siglec, p75/AIRM1 | Type I transmembrane protein, 3 Ig-like-domains | ITIM and ITSM | Sialic acids (α2,8-linkages > α2,6-linkages > α2,3-linkages) | Inhibition | Nicoll G. et al. 1999. J Biol Chem. 274: 34089 Angata T and Varki A. 2000. Glycobiology. 10: 431 Attrill H. et al. 2006. Biochem. J. 397: 271 Crocker PR. et al. 2007. Nature Rev Immunol. 7: 255 |
| SIGLEC | SIGLEC8 | Eosinophils, Basophils, Mast cells | 19 | SAF2, MGC59785, SIGLEC8L | Type I transmembrane protein, 3 Ig-like domains | ITIM and ITSM | Sialic acids (α2,3-linkages > α2,6-linkages) | Inhibition | Nutku E. et al. 2000. Blood. 101: 5014 Floyd H. et al. 2000. J. Biol. Chem. 275: 861 Crocker PR. et al. 2007. Nature Rev Immunol. 7: 255 |
| SIGLEC | SIGLEC9 | NK cells, T cells, B cells, Monocytes, Neutrophils | 19 | CDw329, OBBP-LIKE | Type I transmembrane protein, 3 Ig-like domains | ITIM and ITSM | Sialic acids (α2,3 linkages = α2,6-linkages) | Inhibition | Angata T. and Varki A. 2000. J Biol Chem. 275: 22127 Ikehara Y. et al. 2004. J Biol Chem. 279: 43117 Rapoport EM. et al. 2006. Biochemistry Mosc. 71: 496 Crocker PR. et al. 2007. Nature Rev Immunol. 7: 255 |
| SIRP | SIRP-α | Macrophages, Monocytes, DCs, Granulocytes, Neurons, Astrocytes | 20 | CD172a, SHPS1, P84, MYD-1, BIT, PTPNS1 | 3 Ig-like domains | ITIMs | CD47, Surfactant proteins A and D | Inhibition | Gardai SJ. et al. 2003. Cell. 115: 13 Seiffert M. et al. 1999. Blood. 94: 3633 Barclay A.N. and Brown M.H. 2006. Nature Rev Immunol. 6: 457 |
| SIRP | SIRP-β1 | Macrophages, Neutrophils | 20 | CD172b, DKFZp686A05192, RP4-576H24.1 | 3 Ig-like domains, Forms disulphide-linked dimer, Associates with DAP12 | None | Unknown | Activation | Dietrich J. et al. 2000. J Immunol. 164: 9 Tomasello E. et al. 2000. Eur J Immunol. 30: 2147 Barclay AN. and Brown MH. 2006. Nature Rev Immunol. 6: 457 |
| SIRP | SIRP-β2 | NK cells, T cells | 20 | CD172g, SIRPγ, SIRP-B2, bA77C3.1 | 3 Ig-like domains, No lysine to associate with adaptor molecules | None | CD47 | No signals | Piccio L. et al. 2005. Blood. 105: 2421 Barclay AN. and Brown MH. 2006. Nature Rev Immunol. 6: 457 |
| TREM | TREM-1 | A subset of monocytes and macrophages, Neutrophils, Granulocytes | 6 | - | Type I transmembrane protein, 1 Ig-like domain, Associates with DAP12 | None | Unknown | Activation | Bouchon A. et al. 2000. J Immunol. 164: 4991 Chung DH. et al. 2002. Eur J Immunol. 32: 59 Colonna M. et al. 2003. Nature Rev Immunol. 3: 1 |
| TREM | TREM-2 | Macrophages, DCs, Osteoclasts, Microglia | 6 | Trem2a, Trem2b, Trem2c | Type I transmembrane protein, 1 Ig-like domain, Associates with DAP12 | None | Unknown | Activation or Inhibition | Bouchon A. et al. 2000. J Immunol. 164: 4991 Chung DH. et al. 2002. Eur J Immunol. 32: 59 Colonna M. et al. 2003. Nature Rev Immunol. 3: 1 |