Figure 1

RNAi delivery systems in development stages include RNAi coupled to cell penetrating molecules such as cholesterol (A); or other low molecular weight molecules (B); conjugated to an aptamer that target a specific cell surface receptor (C); conjugated to cell membrane-penetrating polymer that is linked to targeting small molecules (D), complexed with fusion proteins composed of targeting peptide or a fragment of an antibody coupled to an RNA binding domain that is either protamine (E); or poly-arginine (F); or entrapped within nanoparticles (G); or LNPs (H); bearing targeting moieties. Reprinted with permission from ref. 31 Copyright 2011 Gene Therapy.