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Ganglioside-magnetosome complex formation enhances uptake of gangliosides by cells.

Guan F, Li X, Guo J, Yang G, Li X - Int J Nanomedicine (2015)

Bottom Line: The use of GM1-magnetosome complex resulted in the greatest enhancement of ganglioside incorporation by cells.GM3-magnetosome complex significantly inhibited EGF-induced phosphorylation of the epidermal growth factor receptor.Both of these effects were further enhanced by the presence of a magnetic field.

View Article: PubMed Central - PubMed

Affiliation: The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, People's Republic of China.

ABSTRACT
Bacterial magnetosomes, because of their nano-scale size, have a large surface-to-volume ratio and are able to carry large quantities of bioactive substances such as enzymes, antibodies, and genes. Gangliosides, a family of sialic acid-containing glycosphingolipids, function as distinctive cell surface markers and as specific determinants in cellular recognition and cell-to-cell communication. Exogenously added gangliosides are often used to study biological functions, transport mechanisms, and metabolism of their endogenous counterparts. Absorption of gangliosides into cells is typically limited by their tendency to aggregate into micelles in aqueous media. We describe here a simple strategy to remove proteins from the magnetosome membrane by sodium dodecyl sulfate treatment, and efficiently immobilize a ganglioside (GM1 or GM3) on the magnetosome by mild ultrasonic treatment. The maximum of 11.7±1.2 µg GM1 and 11.6±1.5 μg GM3 was loaded onto 1 mg magnetosome, respectively. Complexes of ganglioside-magnetosomes stored at 4°C for certain days presented the consistent stability. The use of GM1-magnetosome complex resulted in the greatest enhancement of ganglioside incorporation by cells. GM3-magnetosome complex significantly inhibited EGF-induced phosphorylation of the epidermal growth factor receptor. Both of these effects were further enhanced by the presence of a magnetic field.

No MeSH data available.


Uptake of GM1-magnetosome complex by YTS-1 cells.Notes: YTS-1 cells were treated with PBS, GM1 plus magnetosomes, GM1-magnetosome complex, or GM1-magnetosome complex under magnetic field (A), as described in M&M. Expression of GM1 on the cell surface was determined by confocal laser scanning microscopy (B) and flow cytometric analysis (C).Abbreviations: FITC, fluorescein isothiocyanate; PBS, phosphate-buffered saline; M&M, materials and methods.
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f3-ijn-10-6919: Uptake of GM1-magnetosome complex by YTS-1 cells.Notes: YTS-1 cells were treated with PBS, GM1 plus magnetosomes, GM1-magnetosome complex, or GM1-magnetosome complex under magnetic field (A), as described in M&M. Expression of GM1 on the cell surface was determined by confocal laser scanning microscopy (B) and flow cytometric analysis (C).Abbreviations: FITC, fluorescein isothiocyanate; PBS, phosphate-buffered saline; M&M, materials and methods.

Mentions: Our working hypothesis was that the uptake of ganglioside into cells is promoted by the use of ganglioside–magnetosome complex to enhance ganglioside solubility and distribution. With bladder cancer cell line YTS-1 (low GM1 expressor)24 as a model, we measured the cell surface expression of GM1 based on binding to CTB.25 The incubation of YTS-1 cells with GM1-magnetosome complex significantly enhanced the fluorescence signal of FITC-labeled CTB for GM1 (Figure 3B), observed under laser confocal fluorescence microscopy. Cellular uptake of GM1-magnetosome complex was much higher under magnetic field (Figure 3A, B). The lower level of FITC signal for GM1 in YTS-1 cells was determined by flow cytometric analysis, whereas cellular uptake of GM1 contributed by GM1-magnetosome complex was significantly increased. And the magnetic field was able to further promote the uptake of GM1-magnetosome complex (Figure 3C). Notably, the fluorescence signal showed that a portion of GM was internalized inside the cells, it was resulted from that GM1 were ingested into YTS-1 cells together with magnetosomes, but not finalizing the transportation of GM1 to the outer of the plasma membranes. These findings indicate that the uptake of GM1-magnetosome complex by YTS-1 cells was enhanced by biocompatibility of the magnetosome membrane, and further enhanced by the presence of a magnetic field.


Ganglioside-magnetosome complex formation enhances uptake of gangliosides by cells.

Guan F, Li X, Guo J, Yang G, Li X - Int J Nanomedicine (2015)

Uptake of GM1-magnetosome complex by YTS-1 cells.Notes: YTS-1 cells were treated with PBS, GM1 plus magnetosomes, GM1-magnetosome complex, or GM1-magnetosome complex under magnetic field (A), as described in M&M. Expression of GM1 on the cell surface was determined by confocal laser scanning microscopy (B) and flow cytometric analysis (C).Abbreviations: FITC, fluorescein isothiocyanate; PBS, phosphate-buffered saline; M&M, materials and methods.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4644171&req=5

f3-ijn-10-6919: Uptake of GM1-magnetosome complex by YTS-1 cells.Notes: YTS-1 cells were treated with PBS, GM1 plus magnetosomes, GM1-magnetosome complex, or GM1-magnetosome complex under magnetic field (A), as described in M&M. Expression of GM1 on the cell surface was determined by confocal laser scanning microscopy (B) and flow cytometric analysis (C).Abbreviations: FITC, fluorescein isothiocyanate; PBS, phosphate-buffered saline; M&M, materials and methods.
Mentions: Our working hypothesis was that the uptake of ganglioside into cells is promoted by the use of ganglioside–magnetosome complex to enhance ganglioside solubility and distribution. With bladder cancer cell line YTS-1 (low GM1 expressor)24 as a model, we measured the cell surface expression of GM1 based on binding to CTB.25 The incubation of YTS-1 cells with GM1-magnetosome complex significantly enhanced the fluorescence signal of FITC-labeled CTB for GM1 (Figure 3B), observed under laser confocal fluorescence microscopy. Cellular uptake of GM1-magnetosome complex was much higher under magnetic field (Figure 3A, B). The lower level of FITC signal for GM1 in YTS-1 cells was determined by flow cytometric analysis, whereas cellular uptake of GM1 contributed by GM1-magnetosome complex was significantly increased. And the magnetic field was able to further promote the uptake of GM1-magnetosome complex (Figure 3C). Notably, the fluorescence signal showed that a portion of GM was internalized inside the cells, it was resulted from that GM1 were ingested into YTS-1 cells together with magnetosomes, but not finalizing the transportation of GM1 to the outer of the plasma membranes. These findings indicate that the uptake of GM1-magnetosome complex by YTS-1 cells was enhanced by biocompatibility of the magnetosome membrane, and further enhanced by the presence of a magnetic field.

Bottom Line: The use of GM1-magnetosome complex resulted in the greatest enhancement of ganglioside incorporation by cells.GM3-magnetosome complex significantly inhibited EGF-induced phosphorylation of the epidermal growth factor receptor.Both of these effects were further enhanced by the presence of a magnetic field.

View Article: PubMed Central - PubMed

Affiliation: The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, People's Republic of China.

ABSTRACT
Bacterial magnetosomes, because of their nano-scale size, have a large surface-to-volume ratio and are able to carry large quantities of bioactive substances such as enzymes, antibodies, and genes. Gangliosides, a family of sialic acid-containing glycosphingolipids, function as distinctive cell surface markers and as specific determinants in cellular recognition and cell-to-cell communication. Exogenously added gangliosides are often used to study biological functions, transport mechanisms, and metabolism of their endogenous counterparts. Absorption of gangliosides into cells is typically limited by their tendency to aggregate into micelles in aqueous media. We describe here a simple strategy to remove proteins from the magnetosome membrane by sodium dodecyl sulfate treatment, and efficiently immobilize a ganglioside (GM1 or GM3) on the magnetosome by mild ultrasonic treatment. The maximum of 11.7±1.2 µg GM1 and 11.6±1.5 μg GM3 was loaded onto 1 mg magnetosome, respectively. Complexes of ganglioside-magnetosomes stored at 4°C for certain days presented the consistent stability. The use of GM1-magnetosome complex resulted in the greatest enhancement of ganglioside incorporation by cells. GM3-magnetosome complex significantly inhibited EGF-induced phosphorylation of the epidermal growth factor receptor. Both of these effects were further enhanced by the presence of a magnetic field.

No MeSH data available.