Figure 3.

(A) BolA-like amphiphilic peptides attach to plasmid DNA to self-assemble viral-mimetic nanoparticles with low cytotoxicity and high gene transfection efficiency [146]. (B) Schematic illustration of the nanoparticle formation process, including peptide assembling, drug loading, and mAb modification, and the proposed mechanism of PNP-D-mAb in CAFs targeting and drug penetration [148]. (C) Schematic illustration of the self-assembly of the peptide (PCL-GFLGR₈GDS) to load the anti-tumor drug DOX for targeted cancer therapy [149]. (D) Schematic representation of the selective cancer-killing processes of RR-22. The specific RGD segment can recognize and bind to cancer membranes, and the overexpressed MMP7 (not available in normal cells) can cleave RR-22 to release the active cell-killing unit [76]. (E) Conjugation of CPPs to antimicrobial peptides enhances membrane permeabilization, membrane translocation, and antibacterial activity [159]. (F) Diagrammatic representation of the transport of bifunctional liposomes across the BBB. The glial cells are transfected by the liposomes after they have been moved through the brain’s endothelial cell layer via receptor-mediated transcytosis [162].