CD3

<StructureSection load='1sy6' size='350' side='right' caption='Structure of human CD3 extracellular domain (grey) complex with antibody light chain (aqua) and heavy chain (red) (PDB entry 1sy6)' scene=>

CD3 (or Cluster of Differentiation 3) is a T-cell co-receptor. The CD3 is composed of γ, δ and two ε chains. These 4 chains associate with the T-cell receptor (TCR) and a ζ chain to form an activation signal in T lymphocytes. CD3 assembles as 3 pairs of dimers: εγ, εδ and ζζ. The intracellular domain of CD3 contains a single immunorecetor tyrosine-based activation motif (ITAM). Drugs which bind to CD3 are tested as immunorepressants.

3D structures of CD33D structures of CD3

Updated on 17-August-2014

CD3 ε chainCD3 ε chain

1a81 – hCD3 ITAM + Syk kinase – human
2jxb – hCD3 domain SH3-1
2k4f – mCD3 ITAM – mouse - NMR
3r08 – mCD3 extracellular domain + antibody

CD3 εγ dimerCD3 εγ dimer

1jbj – hCD3 extracellular domain - NMR
1sy6 – hCD3 extracellular domain + antibody

CD3 εδ dimerCD3 εδ dimer

1xiw – hCD3 extracellular domain + antibody
1xmw – mCD3 extracellular domain ε/sCD3 extracellular domain δ – sheep

CD3 ζ chainCD3 ζ chain

1ygr, 2oq1 – hCD3 ITAM + CD45 protein tyrosine phosphatase
3ik5, 3ioz – hCD3 ITAM + NEF
2hac – hCD3 transmembrane domain - NMR