CD32

Fc fragment of IgG, low affinity IIa, receptor (CD32)
Identifiers
Symbol	FCGR2A
Alt. symbols	FCG2, FCGR2A1, FCGR2
Entrez	2212
HUGO	3616
OMIM	146790
RefSeq	NM_021642
UniProt	P12318
Other data
Locus	Chr. 1 q23

Fc fragment of IgG, low affinity IIb, receptor (CD32)
File:CD32ray.png Crystal structure of the human fcgamma-receptor IIb ectodomain (CD32).^[1]
Identifiers
Symbol	FCGR2B
Alt. symbols	FCG2, FCGR2
Entrez	2213
HUGO	3618
OMIM	604590
RefSeq	NM_004001
UniProt	P31994
Other data
Locus	Chr. 1 q23

Fc fragment of IgG, low affinity IIc, receptor for (CD32)
Identifiers
Symbol	FCGR2C
Entrez	9103
HUGO	15626
RefSeq	NM_201563
UniProt	P31995
Other data
Locus	Chr. 1 q23

CD32 is a surface receptor protein and part of a large population of B cell co-receptors, which act to modulate signaling.

It has a low-affinity for IgG antibodies and down-regulates antibody production in the presence of IgG. This feedback loop acts to lower the production of IgG by B cells when there is a surplus in the body. Monoclonal antibodies can distinguish between CD32A and CD32B.^[2]

References

↑ PDB: 2FCB; Sondermann P, Huber R, Jacob U (March 1999). "Crystal structure of the soluble form of the human fcgamma-receptor IIb: a new member of the immunoglobulin superfamily at 1.7 A resolution". EMBO J. 18 (5): 1095–103. doi:10.1093/emboj/18.5.1095. PMC 1171201. PMID 10064577.; rendered via PyMOL.
↑ Veri MC, Gorlatov S, Li H, et al. (2007). "Monoclonal antibodies capable of discriminating the human inhibitory Fcgamma-receptor IIB (CD32B) from the activating Fcgamma-receptor IIA (CD32A): biochemical, biological and functional characterization". Immunology. 121 (3): 392–404. doi:10.1111/j.1365-2567.2007.02588.x. PMC 2265948. PMID 17386079.

External links

CD32+Antigens at the US National Library of Medicine Medical Subject Headings (MeSH)

v t e Proteins: clusters of differentiation (see also list of human clusters of differentiation)
1-50	CD1 a-c 1A 1D 1E CD2 CD3 γ δ ε CD4 CD5 CD6 CD7 CD8 a CD9 CD10 CD11 a b c d CD13 CD14 CD15 CD16 A B CD18 CD19 CD20 CD21 CD22 CD23 CD24 CD25 CD26 CD27 CD28 CD29 CD30 CD31 CD32 A B CD33 CD34 CD35 CD36 CD37 CD38 CD39 CD40 CD41 CD42 a b c d CD43 CD44 CD45 CD46 CD47 CD48 CD49 a b c d e f CD50
51-100	CD51 CD52 CD53 CD54 CD55 CD56 CD57 CD58 CD59 CD61 CD62 E L P CD63 CD64 A B C CD66 a b c d e f CD68 CD69 CD70 CD71 CD72 CD73 CD74 CD78 CD79 a b CD80 CD81 CD82 CD83 CD84 CD85 a d e h j k CD86 CD87 CD88 CD89 CD90 CD91 - CD92 CD93 CD94 CD95 CD96 CD97 CD98 CD99 CD100
101-150	CD101 CD102 CD103 CD104 CD105 CD106 CD107 a b CD108 CD109 CD110 CD111 CD112 CD113 CD114 CD115 CD116 CD117 CD118 CD119 CD120 a b CD121 a b CD122 CD123 CD124 CD125 CD126 CD127 CD129 CD130 CD131 CD132 CD133 CD134 CD135 CD136 CD137 CD138 CD140b CD141 CD142 CD143 CD144 CD146 CD147 CD148 CD150
151-200	CD151 CD152 CD153 CD154 CD155 CD156 a b c CD157 CD158 (a d e i k) CD159 a c CD160 CD161 CD162 CD163 CD164 CD166 CD167 a b CD168 CD169 CD170 CD171 CD172 a b g CD174 CD177 CD178 CD179 a b CD180 CD181 CD182 CD183 CD184 CD185 CD186 CD191 CD192 CD193 CD194 CD195 CD196 CD197 CDw198 CDw199 CD200
201-250	CD201 CD202b CD204 CD205 CD206 CD207 CD208 CD209 CDw210 a b CD212 CD213a 1 2 CD217 CD218 (a b) CD220 CD221 CD222 CD223 CD224 CD225 CD226 CD227 CD228 CD229 CD230 CD233 CD234 CD235 a b CD236 CD238 CD239 CD240CE CD240D CD241 CD243 CD244 CD246 CD247 - CD248 CD249
251-300	CD252 CD253 CD254 CD256 CD257 CD258 CD261 CD262 CD263 CD264 CD265 CD266 CD267 CD268 CD269 CD271 CD272 CD273 CD274 CD275 CD276 CD278 CD279 CD280 CD281 CD282 CD283 CD284 CD286 CD288 CD289 CD290 CD292 CDw293 CD294 CD295 CD297 CD298 CD299
301-350	CD300A CD301 CD302 CD303 CD304 CD305 CD306 CD307 CD309 CD312 CD314 CD315 CD316 CD317 CD318 CD320 CD321 CD322 CD324 CD325 CD326 CD328 CD329 CD331 CD332 CD333 CD334 CD335 CD336 CD337 CD338 CD339 CD340 CD344 CD349 CD350

Transmembrane receptors: immunoglobulin superfamily immune receptors

Antibody receptor:
Fc receptor

Epsilon (ε)	FcεRI (FcεRII is C-type lectin)
Gamma (γ)	FcγRI FcγRII FcγRIII Neonatal
Alpha (α)/mu (μ)	FcαRI Fcα/μR
Secretory	Polymeric immunoglobulin receptor

Antigen receptor

B cells

Antigen receptor

Co-receptor

stimulate:	CD21/CD19/CD81
inhibit:	CD22

Accessory molecules

Ig-α/Ig-β (CD79)

T cells

Ligands	MHC MHC class I MHC class II
Antigen receptor	TCR: TRA@ TRB@ TRD@ TRG@
Co-receptors	CD8 (with two glycoprotein chains CD8α and CD8β) CD4
Accessory molecules	CD3 CD3γ CD3δ CD3ε ζ-chain (also called CD3ζ and TCRζ)