The present invention provides
protease-cleavage resistant molecules comprising
Shiga toxin effector polypeptides capable of exhibiting potent,
Shiga toxin functions (e.g. subcellular routing and
cytotoxicity). The present invention also provides
protease-cleavage resistant,
cell-targeting molecules for targeting specific
cell types, e.g., infected or
malignant cells. Certain molecules of the present invention are cytotoxic, and certain
cell-targeting molecules of the present invention may be used for the
targeted killing of specific cell types and the treatment of a variety of diseases, disorders, and conditions, including cancers, tumors, growth abnormalities, immune disorders, and microbial infections. Certain cell-targeting molecules of the invention exhibit improved,
in vivo tolerability as compared to related cell-targeted molecules comprising
protease-cleavage sensitive, wild-type,
Shiga toxin effector polypeptides. The cell-targeting molecules of the invention can deliver additional materials, such as, e.g., antigens, cytotoxic agents, and detection-promoting agents, into the interiors of target cells.