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NCI Drug Dictionary

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The NCI Drug Dictionary contains technical definitions and synonyms for drugs/agents used to treat patients with cancer or conditions related to cancer. Each drug entry includes links to check for clinical trials listed in NCI's List of Cancer Clinical Trials.

A murine IgG2a monoclonal antibody with immunosuppressive activity. Muromonab-CD3 binds to and inhibits CD3 on the surface of circulating T-lymphocytes; binding of muromonab-CD3 to CD3-positive T cells results in an early activation of this T cell subset, followed by cytokine release, and subsequently inhibition of T cell functions. This agent may cause the opsonization and elimination of CD3-positive T cells from the circulation by mononuclear phagocytes in the liver and spleen. CD3 is part of the functional T cell receptor (TCR) complex, which is necessary for antigen recognition by T cells, and is required for signal transduction. Check for active clinical trials using this agent. (NCI Thesaurus)

Synonym:Anti-CD3 monoclonal antibody OKT3
monoclonal antibody OKT3
US brand name:Orthoclone OKT3
Abbreviation:MOAB OKT3