αvβ3 integrin recycling is associated with the intracellular trafficking and efflux of cRGDfK-modified PLGA nanoparticles

Understanding the cellular transport mechanisms of active-targeting nanocarriers is essential for improving their therapeutic performance. In this study, cRGDfK-modified poly(lactic-co-glycolic acid) nanoparticles (cRGDfK-PLGA-NPs) were developed as an αvβ3 integrin-targeted delivery system, and their cellular uptake, intracellular trafficking, and efflux behaviors were systematically investigated in HeLa cells. Confocal laser scanning microscopy and HPLC analyses demonstrated enhanced cellular uptake of cRGDfK-PLGA-NPs compared with non-modified nanoparticles in HeLa cells. The uptake advantage was associated with αvβ3 integrin targeting, while pathway-inhibition studies suggested contributions from clathrin-mediated endocytosis and macropinocytosis. Following internalization, cRGDfK-PLGA-NPs were rapidly transported to early endosomes (EE), followed by redistribution to the endocytic recycling compartment (ERC) and gradual accumulation in late endosomes (LE). Real-time and fixed-cell colocalization analyses suggested three intracellular trafficking routes: the EE-LE pathway, a proposed EE-ERC-slow efflux pathway, and an EE-fast efflux pathway. Efflux studies indicated a two-stage kinetic process, with an initial rapid efflux phase (∼5 min) and a subsequent slower phase (∼10 min). To further elucidate the underlying mechanism, the intracellular trafficking behavior of the αvβ3 integrin receptor was investigated using an ELISA-based method, revealing a cyclical pattern of endocytosis and recycling with a periodicity of approximately 5 min. Comparative analysis using a cRGDfK fluorescent probe demonstrated that its rapid efflux behavior closely paralleled receptor recycling dynamics, suggesting that the fast efflux pathway of cRGDfK-PLGA-NPs is associated with αvβ3 integrin-mediated recycling, whereas the slower efflux pathway may involve ERC-mediated transport. Overall, this study provides insights into the potential relationship between target-receptor trafficking dynamics and the intracellular fate of active-targeting nanoparticles. These findings offer a theoretical basis for the rational design and optimization of active-targeting nanocarriers and contribute to improving their therapeutic efficacy.

Abstract from PubMed (PMID 43008688). This entry was added automatically by our daily literature monitor because it matches the topics we follow; read the full paper at the original source.