Nanoparticle-Based Biocompatible and Long-Life Marker for Lysosome Labeling and Tracking

Abstract

In this paper, a novel biocompatible and long-life lysosome labeling and tracking method based on dye entrapped silica nanoparticles (DSiNPs) has been put forward. Through colocalization studies using LysoTracker Green as the standard lysosome marker, it has been demonstrated that DSiNPs selectively accumulated in lysosomes of Hela cells and the photostability of DSiNPs associated with lysosomes was detectable, at least, 30 times as long as that of LysoTracker Green involved in lysosomes. By comparison with LysoTracker Green and Alexa 488-dextran, the fluorescence of DSiNPs could be detected over a 5-day postrecultivation period and the staining pattern in lysosomes could be well retained after cell fixation and permeabilization. In addition, results from MTT assays showed that DSiNPs did not affect the viability of Hela cells at the concentration for lysosome labeling. Primary applications of DSiNPs were then further performed in lysosome tracking in chloroquine-treated Hela cells, and lysosome labeling of differnet cell lines, including MCF-7 cells, MEAR cells, and MSC cells. These results indicated that DSiNPs, therefore, can be used as a biocompatible, long-life, and highly photostable lysosome marker for lysosome-related studies.

Experimental and theoretical comparison of intracellular import of polymeric nanoparticles and small molecules: toward models of uptake kinetics

“…Similar conclusions have been reported for other materials also accumulating in the lysosomes, where no strong evidence of particle export nor degradation could be observed for several hours after cellular uptake. 22,23 In essence, all evidence points to the simple conclusion that once nanoparticles arrive in lysosomes, they remain there. In fact, over time, the only changes observed (by optical imaging techniques) suggest that the intracellular load of nanoparticles is divided between daughter cells quite equally upon cell division ( Figure S9, also observed for silica nanoparticles accumulated in the lysosomes 22 ).…”

Application of Fluorescent Nanoparticles to Study Remodeling of the Endo-lysosomal System by Intracellular Bacteria

“…For example, LysoTracker probes are fluorescent acidotropic probes developed by Molecular Probes (Life Technologies, USA) for lysosome labeling, which can selectively accumulate in cellular compartments with low internal pH and effectively label living cells at nanomolar concentrations 18 . However, long time incubation of LysoTracker probes with cells may induce an increase in lysosomal pH and lead to potential physiological changes of lysosomes 19 . Some large biomolecules, such as fluorophore-labeled dextrans, are also frequently used for endosome/lysosomes labeling.…”

“…Some large biomolecules, such as fluorophore-labeled dextrans, are also frequently used for endosome/lysosomes labeling. However, low-photostability, short-circulating life, and poor retention during fixation hinder their applications in long-term live cell imaging and correlative microscope studies 16,19 . Here, gold-BSA-rhodamine NPs were used as fluid tracers to label the host cellular endo-lysosomal system.…”

“…It has been reported that dye-entrapped silica NPs can be used as a biocompatible, long-living, and highly photostable lysosome marker 19 , and we also compared the behavior of rhodamine-doped silica NPs with varying size (30 -1,000 nm). Proper labeling of late endosomes/lysosomes by silica NPs in non-infected cells and accumulation of NPs in SCV and SIF in Salmonella-infected cells was observed.…”

Natural material-decorated mesoporous silica nanoparticle container for multifunctional membrane-controlled targeted drug delivery

“…43 To improve the drug delivery efficiency, we designed DOX@MSN-NH 2 (HA/CS/HA/FA-CS) and DOX@ MSN-NH 2 (HA/CS/HA) to further evaluate the receptortargeted release properties of the membrane-controlled nanoparticles, and the competitive inhibitory effects of FA and HA on cellular uptake were investigated by CLSM. The folate receptor or CD 44 receptor was blocked on the surface of HepG2 cells by pre-cultivating HepG2 cells with free folate or HA for 2 h. 39 As shown in Figure 10, after incubation for 2 h, the nanoparticles in two different culture media were taken up by HepG2 cells.…”