Targeted Delivery of siRNA Therapeutics to Malignant Tumors

Figure 5

Antibody mediated delivery of siRNA. (a) siRNA can interact with the cationic proteins such as protamine that has been directly conjugated with the antibody. (b) Similar to aptamers, antibodies may be conjugated to a carrier of siRNA (liposomes, polyplexes). In addition to their direct conjugation to the membrane surface of NP, the antibody may be attached to PEG (far right). The antibody ligand includes not only the parent antibody or its Fab fragment, but as in this case, it may include the single-chain variable fragment form of the antibody.