Immunotoxin with in-vivo T cell Suppressant Activity

The invention concerns immunotoxins and methods of using the immunotoxins for the treatment of autoimmune diseases and T cell malignancies. The immunotoxins are targeted via an antibody that is specific to T cells. This allows the specific ablation of malignant T cells and resting T cells. The transient ablation of resting T cells can "reset" the immune system by accentuating tolerizing responses. The toxin portion of the immunotoxin is genetically engineered to maintain bioactivity when recombinantly produced in Pichia pastoris. Data are available in transgenic animals expressing human CD3epsilon which supports the effects of the immunotoxin against T cells.