Engineered anthrax lethal toxin for targeted delivery

摘要

The present invention provides methods and systems for targeted delivery of a compound to a target cell that over-expresses two different proteinases. Specifically, two different modified protective antigen proteins, each comprising a cleavage site recognized by a distinct proteinase in place of the native proteinase cleavage site recognized by furin, are administered in combination with a compound that contains a protective antigen binding site. Upon cleavage by the two proteinases the two modified protective antigen proteins form a hetero-oligomer, allowing the compound to bind to the hetero-oligomer and subsequently to be translocated into the target cell.