CD3 (Cluster of differentiation 3), originally known as T3, is one of the first groups of human T lymphocyte surface antigens recognized by monoclonal antibodies. It has been reported that antibodies against CD3 could either stimulate T cells to divide or inhibit the progress of effector functions according to the conditions used. It plays an important role in T cell and the CD3 T-cell co-receptor helps to activate the cytotoxic T-Cell and T helper cells. The CD3 molecule is composed of a protein complex and consists of four distinct chains. The complex of mammals contains a CD3γ chain, a CD3δ chain, and two CD3ε chains. All these chains associate with T-cell receptor and the ζ-chain to generate an activation signal in T lymphocytes. PSMA (Prostate-specific membrane antigen, also known as Glutamate carboxypeptidase II (GCPII) or N-acetyl-L-aspartyl-L-glutamate peptidase I (NAALADase I)), is a type II transmembrane zinc metallopeptidase and is encoded in humans by the folate hydrolase 1 (FOLH1) gene. Human PSMA contains 750 amino acids and weighs around 84 kDa. The PSMA protein has a 3-part structure involving a 19-amino-acid internal portion, a 24-amino-acid transmembrane portion and a 707-amino-acid external portion. PSMA is a unique transmembrane glycoprotein over-expressed manifold on prostate cancer and neovasculature of most of the solid tumors, but not in the vasculature of the normal tissues. This specific expression of PSMA thereby makes it an important biomarker in the majority of prostate cancers.