Figure 8.

Example of ferritin engineered as a theranostic by displaying a fluorescent protein and encapsulating a cytotoxic peptide. (A) Schematic for genetically fusing a cytotoxic peptide (chamber 1) and a fluorescent protein (chamber 2) to ferritin. (B) Electron micrographs of ferritin, ferritin displaying GFP, and ferritin fused to both GFP and a cytotoxic peptide (“KLAK” repeats). (C) Tumor cryosections from mice treated with a saline control, cytotoxic peptide (KLAK), ferritin-GFP and cytotoxic peptide (sFt-GFP + KLAK), or ferritin fused to both cytotoxic peptide and GFP (KLAK-sFt-GFP). Scale bars are 40 μm. Reprinted with permission.(83)