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Search for "endocytosis" in Full Text gives 92 result(s) in Beilstein Journal of Nanotechnology.
Cytotoxicity of doxorubicin-conjugated poly[N-(2-hydroxypropyl)methacrylamide]-modified γ-Fe2O3 nanoparticles towards human tumor cells
Beilstein J. Nanotechnol. 2018, 9, 2533–2545, doi:10.3762/bjnano.9.236
- their enhanced accumulation inside the cells. The particles are able to penetrate cells by the selected type of endocytosis mechanism: phagocytosis, pinocytosis, or receptor mediated endocytosis [25]. In order to check this hypothesis, cellular uptake of γ-Fe2O3@P(HPMA-MMAA)-Dox nanoparticles was
Nanoparticle delivery to metastatic breast cancer cells by nanoengineered mesenchymal stem cells
Beilstein J. Nanotechnol. 2018, 9, 321–332, doi:10.3762/bjnano.9.32
- ) compared with 3D culture (Figure 4B). To the contrary, MDA-MB-231 internalised 6-fold more QDs in 3D culture compared with 2D (Figure 4B). Such discrepancy in uptake efficacy might be associated with different endocytosis pathways. MCF7 cells internalised QDs through phagocytosis and clathrin/caveolae
- -dependent endocytosis, whereas the clathrin/caveolae-dependent pathway dominated in MDA-MB-231 cells in monocultures (Supporting Information File 1, Figure S2). Cell viability in 3D culture Cells in a 3D culture formed floating and dense spheroids. Therefore, we sought to analyse the effect of the 3D
- facilitating the uptake of MSC-excreted QDs by cancer cells. Our data demonstrate that phagocytosis and clathrin/caveolae-dependent endocytosis are the major QD uptake pathways in MCF7 cells, whereas the clathrin/caveolae-dependent pathway dominated in MDA-MB-231 cells in monocultures (see Supporting
Involvement of two uptake mechanisms of gold and iron oxide nanoparticles in a co-exposure scenario using mouse macrophages
Beilstein J. Nanotechnol. 2017, 8, 2396–2409, doi:10.3762/bjnano.8.239
- negative, must be considered for nanotechnology and nanomedicine in particular to develop to its full potential. Keywords: co-exposure; endocytosis; live cell imaging; nanoparticles; quantitative microscopy; Introduction Over the past two decades, improvements in nanomaterial research were followed by a
- , which can be subdivided into macro- and microscale processes [8]. The first, phagocytosis, involves the ingestion of large particles: NPs or agglomerates typically larger than 0.25 μm in diameter. The second, pinocytosis, includes micro- and macropinocytosis, clathrin-, and caveolin-mediated endocytosis
- , and clathrin- and caveolin-independent endocytosis, involving the ingestion of fluid, molecules, and NPs via small vesicles (<0.15 µm in diameter) [9]. Although NPs have been shown to be taken up by the cells mainly by pinocytotis [9], many factors have been shown to influence the interaction with
Uptake and intracellular accumulation of diamond nanoparticles – a metabolic and cytotoxic study
Beilstein J. Nanotechnol. 2017, 8, 1649–1657, doi:10.3762/bjnano.8.165
- in cultures exposed and unexposed to photoluminescent nanodiamonds. This positive effect can be attributed to the fact that the mechanism of the ND uptake was clathrin-mediated endocytosis, that is, a physiological cellular mechanism for internalization of various bioactive substances from the
Nano-engineered skin mesenchymal stem cells: potential vehicles for tumour-targeted quantum-dot delivery
Beilstein J. Nanotechnol. 2017, 8, 1218–1230, doi:10.3762/bjnano.8.123
- examined via fluorescence imaging using endocytosis inhibitors for the micropinocytosis, phagocytosis, lipid-raft, clathrin- and caveolin-dependent endocytosis pathways. These data showed that QDs were efficiently accumulated in the cytoplasm of MSCs after incubation for 6 h. The main uptake route of QDs
- in skin MSCs was clathrin-mediated endocytosis. QDs were mainly localized in early endosomes after 6 h as well as in late endosomes and lysosomes after 24 h. QDs in concentrations ranging from 0.5 to 64 nM had no effect on cell viability and proliferation. The expression of MSC markers, CD73 and CD90
- suggest that QD-labelled MSCs could be used for targeted drug delivery studies. Keywords: endocytosis; mesenchymal stem cells; quantum dots; stem cell differentiation; Introduction Despite remarkable advances in targeted therapies of various human malignancies, cancer is one of the leading causes of
Uptake of the proteins HTRA1 and HTRA2 by cells mediated by calcium phosphate nanoparticles
Beilstein J. Nanotechnol. 2017, 8, 381–393, doi:10.3762/bjnano.8.40
- flow cytometry. All proteins were readily transported into the cells by cationic calcium phosphate nanoparticles. Notably, only HTRA1 was able to penetrate the cell membrane of MG-63 cells in dissolved form. However, the application of endocytosis inhibitors revealed that the uptake pathway was
- different for dissolved HTRA1 and HTRA1-loaded nanoparticles. Keywords: calcium phosphate; endocytosis; nanoparticles; proteins; Introduction Many receptors for drugs or proteins are located inside cells [1][2]. However, because many biomolecules are not able to penetrate the cell membrane on their own, a
- suitable carrier is required [3][4]. Nanoparticles are readily taken up by cells via endocytosis and are easily able to deliver their cargo into cells across the cell membrane [5][6][7]. Calcium phosphate nanoparticles have demonstrated to be very efficient to transport (bio)molecules into cells [8][9
Viability and proliferation of endothelial cells upon exposure to GaN nanoparticles
Beilstein J. Nanotechnol. 2016, 7, 1330–1337, doi:10.3762/bjnano.7.124
- susceptible for them. In contrast to this situation, the cells take up all the GaN nanoparticles floating in the medium, thus burning energy via the endocytosis process and slowing down the proliferation activity. Conclusion We found that the interaction of porcine endothelial cells with GaN nanoparticles
On the pathway of cellular uptake: new insight into the interaction between the cell membrane and very small nanoparticles
Beilstein J. Nanotechnol. 2016, 7, 1296–1311, doi:10.3762/bjnano.7.121
- : ATP depletion; calcium crystallization; cytotoxicity; endocytosis; HeLa cells; LDH; mesenchymal stem cells; morphology; necrosis; particle size; silica nanoparticles; TEM; Introduction Silicon dioxide nanoparticles (SiNPs) are used in a wide range of commercially available products to improve product
- see a size dependency of NP endocytosis (Figure 4, Figure 10, Figure 11). The endocytic route for the larger of our examined NPs (SiNP-22 and SiNP-12) can be described as following: First the NPs are taken up as individuals or in small groups and are found in the cytosol with tightly wrapping membrane
- additional silica layer is likely to change the viscoelastic properties of the cell membrane yielding an increased maximum bending radius. Nevertheless, the cell manages to perform the pinch-off which is indicative for an active endocytic process. Moreover, when suppressing any active endocytosis by cooling
Improved biocompatibility and efficient labeling of neural stem cells with poly(L-lysine)-coated maghemite nanoparticles
Beilstein J. Nanotechnol. 2016, 7, 926–936, doi:10.3762/bjnano.7.84
- ]. Endocytosis as a process of internalization of foreign materials can be divided into two major groups, phagocytosis for larger particles and pinocytosis for nanoparticles. Pinocytosis can be further subdivided depending on the size of particles into clathrin-mediated, caveolae, and macropinocytosis [25]. To
- -dependent process macropinocytosis cytochalasine D, inhibitor of microtubule function involved in intracellular vesicle trafficking nocodazole, inhibitor of the clathrin-mediated endocytosis phenylarsine oxide and filipin, which blocks caveolae pathways [25]. Our results suggested that the internalization
- determine the mechanism of nanoparticle uptake, NSCs were pre-treated with inhibitors of endocytosis for 30 min and then incubated with nanoparticles for 48 h in the presence of the inhibitor [25]. The inhibitors were phenylarsine oxide (12 nM), cytochalasin D (60 nM), nocodazole (20 nM) and filipin (0.3 µg
The role of morphology and coupling of gold nanoparticles in optical breakdown during picosecond pulse exposures
Beilstein J. Nanotechnol. 2016, 7, 869–880, doi:10.3762/bjnano.7.79
- surface of cell [6][7][8][9], modification of gold nanoparticle surfaces to cause binding to each other [10][11] or endocytosis [12]. Nanoparticle assemblies exhibit optical behavior that differs from single particles. The changes in the optical behavior of nanoparticle assemblies are governed by surface
Tight junction between endothelial cells: the interaction between nanoparticles and blood vessels
Beilstein J. Nanotechnol. 2016, 7, 675–684, doi:10.3762/bjnano.7.60
- , while a significant change occurred in myoblasts after 4 h [87]. Recent studies revealed that hydrodynamic conditions influence the endothelial endocytosis of nanocarriers. By using nanocarriers targeted to PECAM-1, the authors found a flow-stimulated endocytosis of nanocarriers through eliciting
pH-Triggered release from surface-modified poly(lactic-co-glycolic acid) nanoparticles
Beilstein J. Nanotechnol. 2015, 6, 2504–2512, doi:10.3762/bjnano.6.260
- taken up by endocytosis. During the process of endocytosis, nanoparticular drug carriers most often end up in endolysosomes with a reduced internal pH value. In order to provide improved accessibility of the drug to the whole cell, membrane destruction of the endolysosomal bilayer would be beneficial
PLGA nanoparticles as a platform for vitamin D-based cancer therapy
Beilstein J. Nanotechnol. 2015, 6, 1306–1318, doi:10.3762/bjnano.6.135
- pancreatic cell lines, S2-013 and hTERT-HPNE, was reported. The in vitro proliferation assay showed that the encapsulation of calcitriol enhanced its antiproliferative activity. The efficient cell internalization by an endocytosis mechanism of PLGA NPs and their rapid endo-lysosomal escape observed in this
- study could explain the benefits of the drug encapsulation in the NPs. Tahara et al. showed that PLGA NPs are efficiently internalized by A549 cells by an endocytosis mechanism, partially mediated by a clathrin [34], which can explain the NP-enhanced calcitriol activity reported in this work. Therefore
Protein corona – from molecular adsorption to physiological complexity
Beilstein J. Nanotechnol. 2015, 6, 857–873, doi:10.3762/bjnano.6.88
- cellular uptake. A possible contribution to this observation is that, in presence of free proteins, the cellular endocytosis machinery was also occupied with internalization of the freely dissolved protein. However, intriguing differences were found between the effects of the different coronae, essentially
- uptake. The notion that rather the kinetics of membrane binding can be affected by the presence and nature of the protein corona, than the kinetics of the actual endocytosis process, allows novel strategies in this context. The role of this finding for the passive uptake of NPs by cells, remains
Influence of gold, silver and gold–silver alloy nanoparticles on germ cell function and embryo development
Beilstein J. Nanotechnol. 2015, 6, 651–664, doi:10.3762/bjnano.6.66
- mattering for fertilisation. The fact that it may be difficult for nanoparticles to enter into these highly specialised cells does not seem unreasonable. Nanoparticles have been observed to enter into somatic cells mostly via endocytosis [59][60], a cellular mechanism which sperm do not possess
Biological responses to nanoscale particles
Beilstein J. Nanotechnol. 2015, 6, 380–382, doi:10.3762/bjnano.6.37
- small molecules or nanoparticles can cross membranes with the mediation of specialized proteins, larger nanoparticles exhibit more complex entry mechanisms that are jointly described as endocytosis. The entry mechanism of nanoparticles into living cells and their subsequent trafficking within the cell
Comparative evaluation of the impact on endothelial cells induced by different nanoparticle structures and functionalization
Beilstein J. Nanotechnol. 2015, 6, 300–312, doi:10.3762/bjnano.6.28
- by caveolae-mediated endocytosis and nanoparticles with a size of 40 nm are taken up by clathrin-mediated internalization and macropinocytosis. Our results can be summarized to formulate five general rules, which are further specified in the text and which determine the biocompatibility of
- vacuoles and 4 to 20 nm sized ones in endosomes and lysosomes. A smaller size (4 nm) as well as coupling of polar groups (e.g., NH2) accelerate the uptake and result in the loss of cell viability. Uptake mechanisms In order to assess the mechanisms of endocytosis that are used for the internalization of
- nanoparticles by macrophages after the treatment with genistein [56]. Interestingly, the application of chlorpromazine, selectively affecting clathrin-mediated endocytosis [57][58], led to an increased accumulation of Au@ Fe3O4 and Fe3O4 nanoparticles in HMEC-1 (Figure 6a and Figure 6c). After incubation of
The effect of surface charge on nonspecific uptake and cytotoxicity of CdSe/ZnS core/shell quantum dots
Beilstein J. Nanotechnol. 2015, 6, 281–292, doi:10.3762/bjnano.6.26
- CdSe cores. Pretreatment of cells with pharmacological inhibitors suggested that the uptake of nanoparticles was largely due to receptor-independent endocytosis or spontaneous entry for carboxylated and zwitterionic QDs, while for amine-functionalized particles, formation of vesicles was observed. The
- carried out for 30 min at room temperature, cells were then washed and taken to a microscope. Inhibition of endocytosis MDCKII cells were pretreated with 25 μg/mL chlorpromazine [44], 30 μg/mL 5-(N,N-dimethyl)amiloride [45] and 1 μg/mL filipin III [46] (predissolved in dimethyl sulfoxide 0.5 μg/μL) upon
- overall fluorescent signal by applying standard deviation (for QDs) and averaging (for cells), post-processing algorithms to a 20-frame image sequence obtained during each measurement. CPZ: chlorpromazine (inhibitior of clathrin-mediated endocytosis), DMA: dimethylamyloride hydrochloride (inhibitor of
Tailoring the ligand shell for the control of cellular uptake and optical properties of nanocrystals
Beilstein J. Nanotechnol. 2015, 6, 232–242, doi:10.3762/bjnano.6.22
- general (positively or negatively) show a much more efficient adsorption of these proteins needed for the recognition by macrophages [33][34]. Other cell types follow the endocytotic process, which can be receptor mediated or unspecific. For the uptake via endocytosis a positive surface charge has shown
- tested samples and the obtained results are summarized in Table 2. None of the samples showed unspecific adhesion or uptake on A549 cells in serum containing medium after 4 h, although the containers range in a suitable size range between 40 and 80 nm for endocytosis [22]. Even the positively charged
Mechanical properties of MDCK II cells exposed to gold nanorods
Beilstein J. Nanotechnol. 2015, 6, 223–231, doi:10.3762/bjnano.6.21
- fluorescence and dark-field microscopy. Conclusion: We found that cells exposed to CTAB coated gold nanorods display a concentration-dependent stiffening that cannot be explained by the presence of CTAB alone. The stiffening results presumably from endocytosis of particles removing excess membrane area from
- . Although it is conceivable that excessive endocytosis leads to a loss of excess surface area the collapse of the plasma membrane on the elastic and considerably stiff actomyosin cortex is also important to explain the mechanical response. Therefore, we will base the following discussion mainly on the
- wrapped by the plasma membrane and thereby consuming all excess surface area. A reduction of surface area immediately leads to apparent cell stiffening at larger strains. Enforced endocytosis leads to a decrease in overall membrane area that causes increased resistance against area dilatation. Pre-stress
Caveolin-1 and CDC42 mediated endocytosis of silica-coated iron oxide nanoparticles in HeLa cells
Beilstein J. Nanotechnol. 2015, 6, 167–176, doi:10.3762/bjnano.6.16
- line. Cells were transfected with specific siRNAs against Caveolin-1, Dynamin 2, Flotillin-1, Clathrin, PIP5Kα and CDC42. Knockdown of Caveolin-1 reduces endocytosis of superparamagnetic iron oxide nanoparticles (SPIONs) and silica-coated iron oxide nanoparticles (SCIONs) between 23 and 41%, depending
- on the surface characteristics of the nanoparticles and the experimental design. Knockdown of CDC42 showed a 46% decrease of the internalization of PEGylated SPIONs within 24 h incubation time. Knockdown of Dynamin 2, Flotillin-1, Clathrin and PIP5Kα caused no or only minor effects. Hence endocytosis
- in HeLa cells of iron oxide nanoparticles, used in this study, is mainly mediated by Caveolin-1 and CDC42. It is shown here for the first time, which proteins of the endocytotic pathway mediate the endocytosis of silica-coated iron oxide nanoparticles in HeLa cells in vitro. In future studies more
Increasing throughput of AFM-based single cell adhesion measurements through multisubstrate surfaces
Beilstein J. Nanotechnol. 2015, 6, 157–166, doi:10.3762/bjnano.6.15
- CAM has been studied by SCFS. It was shown by SCFS that collagen I binding integrins down-regulate the avidity of fibronectin binding integrins by an increased endocytosis in HeLa cells [30]. The classical SCFS setup, where the adhesion of a cantilever-bound cell to a substrate is probed, has a
Synthesis of boron nitride nanotubes and their applications
Beilstein J. Nanotechnol. 2015, 6, 84–102, doi:10.3762/bjnano.6.9
- addition, the authors evaluated the toxicity of BNNTs according to the cell type and endocytosis ability of the cells. In particular, RAW 264.7 had high endocytosis capability as compared to A549 and 3T3-L1 cell types, and HEK293 showed low endocytosis capability. The results showed that the BNNTs slightly
- related to the cell type and the ability to perform endocytosis [77]. The morphology and viability of the GC–BNNTs-exposed HUVECs cells were also investigated [71]. The cells were incubated at increasing concentrations of GC–BNNTs for 48 and 72 h. The cell morphology and cell viability by amido black
Mammalian cell growth on gold nanoparticle-decorated substrates is influenced by the nanoparticle coating
Beilstein J. Nanotechnol. 2014, 5, 2479–2488, doi:10.3762/bjnano.5.257
- with the negatively charged membrane [21][22], and to the sedimentation behavior of the particles which is related to their colloidal stability under physiological conditions [33]. The uptake was likely caused by non-specific endocytosis or macropinocytosis. Therefore, we expected an even stronger
Intake of silica nanoparticles by giant lipid vesicles: influence of particle size and thermodynamic membrane state
Beilstein J. Nanotechnol. 2014, 5, 2468–2478, doi:10.3762/bjnano.5.256
- models and indicate that these models have to be extended in order to capture the interaction between nanomaterials and biological membranes correctly. Keywords: cells; endocytosis; engulfment; fission; gel phase; giant unilamellar lipid vesicles (GUV); lipid membranes; liquid phase; nanoparticle
- small nanoparticles can directly penetrate cell and model membranes [7][8], particles significantly larger than the membrane thickness (3–4 nm) are usually taken up by endocytosis [9][10]. The physical aspects of an interaction between cell membranes and nanoparticles are still not well understood
- . Especially the dependence of the uptake efficiency on the particle size is still an important topic [11][12]. Usually, a complex cell machinery is involved in endocytosis. However, particle uptake including the engulfment by the membrane has also been reported for red blood cells, which are known for not
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