Diphtheria toxin-derived protein for targeted delivery of nanoparticles

Over the last one decade, various types of nano-formulations have been developed and approved for use. However, cell-specific delivery of nanoparticles (NPs) is still a challenge. Antibodies and peptides are often used for... [ view full abstract ]

Over the last one decade, various types of nano-formulations have been developed and approved for use. However, cell-specific delivery of nanoparticles (NPs) is still a challenge. Antibodies and peptides are often used for targeted delivery of NPs. In the present work, we have used a small protein derived from Diphtheria toxin to home NPs to specific cells. Diphtheria toxin (DT) binds to a specific receptor on cell surface and is internalized by receptor-mediated endocytosis. This receptor is overexpressed in various types of cancer cells. We have expressed the recombinant receptor-binding domain of DT (RDT) that binds to the cell surface receptor. We have coated PLGA NPs with RDT. Coating, with RDT, is revealed by UV spectroscopy and Bradford’s assay. RDT coated NPs showed enhanced cellular uptake of NPs in U-87 MG cells with specific DT receptor. The internalization of RDT coated NPs is shown by Flow cytometer and Fluorescent microscope. These RDT-coated NPs can be used for delivery of a chemotherapeutic agent to cells expressing DT-receptors.