Figure 7.

Computationally designed nanoparticle O3–33 was redesigned for siRNA delivery. The computationally designed octahedral protein nanoparticle O3–33 (porous protein cage) containing 144 hexahistidine tags on its surface was redesigned to have a positively charged interior to electrostatically associate with nucleic acid in vitro (positively charged capsule loaded with nucleic acid).^19,166 The authors reported nuclease protection, uptake of the nanoparticles by HeLa cells, and subsequent cargo release leading to knockdown of intracellular GFP mRNA. The authors attributed successful endosomal escape to the hexahistidine tags. Reprinted with permission.(166)