muromonab-CD3

Muromonab-CD3 is a murine monoclonal antibody directed against the CD3 epsilon chain on the surface of human T cells. It was the first monoclonal antibody approved for clinical use in humans. The drug works by binding to the T-cell surface glycoprotein CD3 epsilon chain, which is part of the T cell receptor-CD3 complex. This binding initially activates T cells but subsequently induces blockage and apoptosis of T cells, preventing them from causing organ rejection. Muromonab-CD3 effectively removes CD3-positive T lymphocytes from circulation, blocking T cell receptor function and inhibiting both the generation and function of cytotoxic T cells. It was primarily used to reduce natural immunity in patients receiving organ transplants (kidney, liver, heart, and combined kidney-pancreas) and for treating acute rejection episodes, particularly those resistant to conventional treatment. The drug was withdrawn from use in 2010.

Brand names

Orthoclone OKT3

Other names

muromonabOrthocloneOrthoclone OKT 3