IL-2-PE40 is a recombinant chimeric protein composed of interleukin-2 (IL-2) and of Pseudomonas endotoxin (PE40), minus its cell-binding domain. This toxin, once internalized, kills cells by irreversibly inhibiting protein synthesis. Hence, cells bearing IL-2 receptors on their surface, which are prime targets for this toxin, can be effectively removed from an organism without producing too many untoward side effects. In experimental autoimmune uveitis (EAU), T cells play a major role. Once activated, these T cells express on their cell surface IL-2 receptors, which can be targeted by the chimeric toxin and eliminated. We have demonstrated that this toxin is able to reduce significantly the incidence and severity of experimentally induced uveitis. IL-2PE40 is also able to reduce the incidence and severity of corneal graft rejection following systemic administration of the toxin.
