Figure 3

Structure and/or functional mechanism of some scFv-based drug carriers. (A) Monovalent and bivalent formats of Ranpirnase-scFv fusion peptide. Ranpirnase and scFv are joined together with a linker peptide. (B) Schematic view of a doxorubicin-loaded bispecific IL. The targeting ligand is a fusion peptide composed two scFv molecules, anti-FAP scFv and anti-CD105 scFv. (C) Deferoxamine (DFO)-loaded anti-FAP IL. Anti-FAP scFvs contain a cysteine residue in their linker region that makes a covalent bond with PEG molecules on the surface of liposomes. The resultant ILs are able to bind FAP proteins expressed on the surface of TGF β1-activated fibroblasts and reduce collagen deposition. (D) Adriamycin (ADM)-loaded scFv molecule. Dextran can serve as a linker for effectively loading ADM molecules on scFv molecules. (E) A nanodisk composed of reconstituted high-density lipoprotein particles and apo-AI-anti-CD20 scFv fusion peptide to specifically deliver curcumin to CD20-positive non-Hodgkins lymphoma (NHL) cells. The fusion peptide constitutes the protein scaffold of nanodisk and binds NHL cells through its scFv moiety. The structure of nanodisk has been derived from the work of Crosby and colleagues (71).