CD3 is a component of T cell surface receptor (TCR), it cantains 5 invariable chains: gamma- , delta-, epsilon-, and zeta/eta Clevers et al. (1988) showed the TCR/CD3 complex consists of either a TCR alpha/beta or TCR gamma/delta heterodimer coexpressed at the cell surface with the invariant subunits,CD3 is responsible for the signal transduction of the TCR.
