Gold nanoparticles (AuNPs) have been widely investigated as potential nanocarriers for drug delivery. In the present study, AuNPs were conjugated to a peptide that has a C-terminal Lys–Asp–Glu–Leu (KDEL) motif. In a pulse-chase study, time-course sampling revealed that AuNP-delivered KDEL peptides were rapidly localized to the endoplasmic reticulum (ER) in 5 to 15 min, and after 1 h the majority of peptides were localized to the ER. Clathrin-coated vesicles and Golgi apparatus were also involved during the intracellular trafficking of KDEL peptide gold (AuNP-KDEL) nanoconstructs. Furthermore, overexpression of KDEL receptor (KDELR) significantly enhanced KDEL peptide uptake in both f... More
Gold nanoparticles (AuNPs) have been widely investigated as potential nanocarriers for drug delivery. In the present study, AuNPs were conjugated to a peptide that has a C-terminal Lys–Asp–Glu–Leu (KDEL) motif. In a pulse-chase study, time-course sampling revealed that AuNP-delivered KDEL peptides were rapidly localized to the endoplasmic reticulum (ER) in 5 to 15 min, and after 1 h the majority of peptides were localized to the ER. Clathrin-coated vesicles and Golgi apparatus were also involved during the intracellular trafficking of KDEL peptide gold (AuNP-KDEL) nanoconstructs. Furthermore, overexpression of KDEL receptor (KDELR) significantly enhanced KDEL peptide uptake in both free and AuNP-conjugated forms. These data indicate that the AuNP-KDEL nanoconstructs are internalized via a clathrin-mediated pathway and trafficked to the ER via a retrograde transport pathway, bypassing the lysosomal degradation pathway. Thus, this novel approach to development of nanoconstruct-based drug delivery has the potential to evade intracellular degradation, enhancing drug efficacy.From the Clinical EditorIn this study, gold nanoparticles were conjugated to a peptide with KDEL motif, resulting in internalization via a clathrin-mediated pathway and trafficking to the ER via retrograde transport meanwhile bypassing the lysosomal degradation pathway. This method results in a potential evasion of intracellular degradation, and enhanced drug efficacy.