Anti CD3 antibodies

Anti CD3 antibodies

Muromonab-CD3 is a murine monoclonal antibody that specifically reacts with the T cell receptor-CD3 complex on the surface of circulating human T cells. The CD-3 complex transduces the signal for the T cell to react to the foreign antigen, proliferate, and attack the foreign matter. The action of muromonab-CD3 results in a transient activation of T cells, release of cytokines, and blocking of T-cell proliferation and differentiation.

In the body, muromonab-CD3 acts in 2 phases. During the first phase, which begins immediately after injection, circulating T cells are depleted, primarily as a result of opsonization in the liver and cytolysis. The second phase involves antigenic modulation. The CD-3 complex on the cell surface is removed, producing

immuno-incompetent T cells, without further depletion of the T-cell population. The onset of effect is seen several minutes after injection.

Muromonab-CD3 is indicated for the treatment of (corticosteroid-resistant) renal graft rejection and acute rejection in liver and heart transplant.

All patients experience a first-dose response, called the "cytokine release syndrome" and induced by T-cell activation, which results in mitogenesis or the release of numerous cytokines and lymphokines into the systemic circulation. This release of cytokines stimulates the production of leukotrienes, prostaglandins, and endoperoxides that contribute to fever, chills, and mild pulmonary and GI symptoms. The symptoms typically appear within 1 hour after the first 1 or 2 doses and may persist for several hours. Approximately 5% experience more serious reactions such as cardiopulmonary distress, seizures, encephalopathy, meningitis, renal insufficiency, and graft thrombosis.