Construction,Expression And Activity Of The Anti-human CD3 Single Chain Antibody Fragment

CD3 molecule is a differential antigen which is present on the surface of mature lymphocytes. The CD3 molecule exists as a TCR/ CD3 complex by tightly associated with T-cell receptor (TCR). When T- cell receptor binding and recognizing antigen, the signal is transducted into T cell through CD3 molecules, as a result of TCR / CD3 triggering, lead to release of cytokines and activate the T lymphocytes. Anti-CD3 McAbs may disrupt T cell by blocking and modutating the TCR and they strongly supress T cell-mediated responses by causing T cell depletion. The anti -CD3 McAb(OkT3) was first used as an immunosupresive agent in transplant recipients. It is also found that anti-CD3 McAbs have the ability to induce T lymphocytes activation and proliferation. There is a hypothesis that the anti-CD3 McAbs change the conformation of TCR/CD3 as they binding the CD3 moleucles, induce the release of...