scholarly journals Quantification and Imaging of Antigens on Cell Surface with Lipid-Encapsulated Fluorescent Nanodiamonds

Micromachines ◽  
2019 ◽  
Vol 10 (5) ◽  
pp. 304
Author(s):  
Feng-Jen Hsieh ◽  
Yen-Wei Chen ◽  
Yuen Hui ◽  
Chun-Hung Lin ◽  
Huan-Cheng Chang
Keyword(s):  
Cell Surface ◽  
Binding Capacity ◽  
Specific Targeting ◽  
Confocal Fluorescence ◽  
Fluorescent Nanodiamonds ◽  
Modulated Fluorescence ◽  
Targeting Ability ◽  
Confocal Fluorescence Imaging ◽  
Biology Research ◽  
Biological Buffers

Quantifying the density and locating the position of antigens on cell surface has been a challenge in molecular biology research. The challenge lies in the need for a chemically and photophysically stable fluorophore to achieve the required sensitivity and accuracy. Here, we present a method suitable for the purpose by using lipid-encapsulated fluorescent nanodiamonds (FNDs) of 35 nm in diameter as biolabels. The encapsulation of FNDs in biotinylated phospholipids not only facilitates good dispersion of the particles in biological buffers, but also endows them with high specific targeting ability. We demonstrated a viable application of the technique for biotin-mediated immunostaining of antigens on fixed human cells, identifying their positions by two-color confocal fluorescence imaging, and determining their densities by magnetically modulated fluorescence detection. A binding capacity of 6 ± 1 × 104 antigens/cell was measured specifically for CD44 on HeLa cell surface. The result agreed well with the assay of R-phycoerythrin-conjugated antibodies by flow cytometry, supporting the reliability of this new nanoparticle-based method.

Confocal Fluorescence Imaging of Photosensitised DNA Denaturation in Cell Nuclei

2005 ◽  
Author(s):  
Tytus Bernas ◽  
Elikplimi K. Asem ◽  
J. Paul Robinson ◽  
Peter R. Cook ◽  
Jurek W. Dobrucki
Keyword(s):  
Fluorescence Imaging ◽  
Dna Denaturation ◽  
Cell Nuclei ◽  
Confocal Fluorescence ◽  
Confocal Fluorescence Imaging

Pore selectivity and electron transfers in HZSM-5 single crystals: a Raman microspectroscopy mapping and confocal fluorescence imaging combined study

2020 ◽  
Vol 22 (22) ◽  
pp. 12745-12756
Author(s):  
A. Moissette ◽  
M. Hureau ◽  
M. Moreau ◽  
J. P. Cornard
Keyword(s):  
Single Crystals ◽  
Fluorescence Imaging ◽  
Single Particle ◽  
Raman Microspectroscopy ◽  
Single Particle Level ◽  
Confocal Fluorescence ◽  
Particle Level ◽  
Confocal Fluorescence Imaging ◽  
Electron Transfers

Electron transfers at the single particle level in HZSM-5 zeolite are followed by combining Raman microspectroscopy mapping and confocal fluorescence imaging. The effects of pore accessibility and guest diffusion on reactivity are investigated.

Physicochemical roles of soluble metal cations in the outer membrane of Escherichia coli K-12

1986 ◽  
Vol 32 (7) ◽  
pp. 594-601 ◽  
Author(s):  
F. G. Ferris ◽  
T. J. Beveridge
Keyword(s):  
Cell Surface ◽  
Outer Membrane ◽  
Metal Binding ◽  
Metal Salt ◽  
Binding Capacity ◽  
Cell Surface Hydrophobicity ◽  
Surface Hydrophobicity ◽  
Metallic Ions ◽  
Intact Cells ◽  
K 12

Atomic absorption spectroscopy of isolated native and EDTA-modified (lipopolysaccharide-depleted) outer membrane revealed trace amounts of potassium, manganese, and iron (1.0–7.0 nmol/mg dry weight outer membrane). Sodium, magnesium, and calcium were approximately one order of magnitude more plentiful, but EDTA-modified outer membrane was deficient in calcium. When metal-binding assays were conducted to find the binding capacity of native and EDTA-modified outer membrane, potassium bound poorly compared with sodium. However, there was no difference in the binding of these ions between the OM preparations. In contrast, reduced amounts of magnesium, calcium, manganese, and iron III bound to the EDTA-modified OM. Partitioning of intact cells in a biphasic dextran–polyethyleneglycol system indicated that the reduced lipopolysaccharide content of the EDTA-modified outer membrane increased the hydrophobicity of the cell surface. Exposure of control and EDTA-treated cells to divalent metal salt solutions before phase partitioning also increased cell surface hydrophobicity. Freeze-etching showed that sodium ions had no effect on the membrane fractures observed in control cells, but with EDTA-treated cells, this cation increased the occurrence of small outer membrane fractures (plateaus) which are characteristic of EDTA treatment. Both magnesium and manganese increased the frequency of outer membrane cleavage in control cells, whereas calcium did not. In contrast, all three divalent metallic ions increased the frequency and extent of cleavage in the outer membrane of EDTA-treated cells.

scholarly journals Immune complex receptors on cell surface. I. Ultrastructural demonstration of macrophages.

1976 ◽  
Vol 24 (8) ◽  
pp. 948-955 ◽  
Author(s):  
P E McKeever ◽  
A J Garvin ◽  
S S Spicer
Keyword(s):  
Electron Microscopy ◽  
Horseradish Peroxidase ◽  
Cell Surface ◽  
Immune Complex ◽  
Immune Complexes ◽  
External Surface ◽  
Binding Capacity ◽  
Ultrastructural Localization ◽  
Soluble Complex ◽  
Receptor Sites

A method is described for ultrastructural localization of immune complex receptors on the surface of viable peritoneal exudate cells. The technique entails incubation with a soluble complex of horseradish peroxidase (HRP) and specific antibody to HRP at 4 degrees C followed by exposure to diaminobenzidine and processing for electron microscopy. The bound immune complexes were evident as focal deposits of HRP reaction product, adhering closely to the external surface of macrophages with an uninterrupted periodicity varying between 30 and 120 nm. Following incubation with an insoluble immune complex containing a higher proportion of antibody, receptor sites stained frequently, but large aggregates adhered to the cells. Rinsing cells after staining with soluble complexes partially displaced the bound immune complexes. Fixation prior to exposure to immune complexes largely eliminated the binding capacity of the immune complex receptors.

Hyperspectral confocal fluorescence imaging of cells

2007 ◽  
Author(s):  
David M. Haaland ◽  
Howland D. T. Jones ◽  
Michael B. Sinclair ◽  
Bryan Carson ◽  
Catherine Branda ◽  
...  
Keyword(s):  
Fluorescence Imaging ◽  
Confocal Fluorescence ◽  
Confocal Fluorescence Imaging
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