Plasma Membrane Dynamics

The plasma membrane (PM) separates the intracellular environment from the extracellular space and protects the cells from the extracellular environment. The PM plays important roles in selective permeation or signaling between cells etc.

• • Visualization of Plasma membrane

    • Product Range

      Category	Product	Size	CAT. No.
      Plasma Membrane Staining Dyes	PlasMem Bright Green	100 μl x 1	P504
      	PlasMem Bright Red	100 μl x 1	P505

      
      

      Note: 1 tube (100 µl), 10 assays at 35 mm dish, 10 assays at µ-Slide 8 well

      Features

      •  Applicable to live and fixed cells
      •  High retentivity of reagents with low toxicity
      •  Just add reagents into medium
      •  Comparison with other products:
      

      

      Experimental Examples

      •  Clear visualization of plasma membrane

      Observe morphology of neuron (differentiated SH-SY5Y cells) and localization of mitochondria in axon.

      

      •  High retentivity on plasma membrane

      HeLa cells stained with each plasma membrane staining reagent were incubated for 24 hours and each the resulting fluorescent image was compared. PlasMem Bright series had higher retentivity in plasma membrane than other products.

      

  • Visualization of Endocytosis

    • Product Range

      Category	Product	Size	CAT. No.
      Endocytosis Detection Dye	ECGreen-Endocytosis Detection	40 μl x 1	E296

      
      

      Note: 1 tube (40 µl), 20 assays at 35 mm dish, 20 assays at µ-Slide 8 well

      ECGreen is a pH dependent fluorescence dye that localizes to vesicle membrane. The visualization of endocytosis using the ECGreen is a more direct method than fluorescent analogs and allows visualization endocytosis from the stage of early endosomes.

      

      Features

      •  Stain vesicle membrane precisely

      Fluorescent Dye-Dextran Conjugates or membrane staining reagents are used to visualize endocytosis. However, they have limitations in observing dynamics of endosomes in live cells in terms of precision of staining or retentivity of reagent. ECGreen is the reagent that over comes the limitations.

      

      •  Clear visualization of intracellular vesicular trafficking

      It has been known that Wortmannin inhibits the recycling of endosomes or transition to lysosomes and causes enlargement of endosomes. To evaluate these changes caused by Wortmannin, early endosomes were co-stained by ECGreen and Rab5-RFP (marker protein of early endosomes), and lysosomes were co-stained by ECGreen and lysosome staining reagent. In adding Wortmannin, ECGreen was colocalized with enlarged endosomes (Rab5-RFP). On the other hand, ECGreen wasn’t colocalized with lysosomes.

      

  • Visualization of Exosome

    • Product Range

      Product Name	Labeling Dyes	Size	CAT. No.
      ExoSparkler Exosome Membrane Labeling Kit	Green	5 samples	EX01
      	Red	5 samples	EX02
      	Deep Red	5 samples	EX03
      ExoSparkler Exosome Protein Labeling Kit	Green	5 samples	EX04
      	Red	5 samples	EX05
      	Deep Red	5 samples	EX06

      
      

      Note: Protein amount: 1-10µg/ sample, Particle count: 10 to 100 x 10^8 /samples (As purified exosome using ultracentrifugation)

      Recent findings suggest that exosomes, a form of extracellular vesicle (EV), contribute to malignant transformation and the metastasis of cancer. Consequently, intercellular communication via exosomes is attracting considerable interest in the scientific community.

      To shed light on such communication, labeling techniques based on fluorescent dyes have been used. Fluorescent dyes that label the cellular membrane are commonly used for exosome labeling because the lipid bilayer in exosomes is a good target for labeling.

      

      Features

      •  ExoSparkler series does not allow extracellular aggregation

      Exosomes stained with ExoSparkler’s Mem Dye-Deep Red or an alternative product (green or red) were added to each well containing HeLa cells. The labeled exosomes taken into HeLa cells were observed by fluorescent microscopy. As a result, extracellular fluorescent spots suspected of dye aggregations were seen in each well containing the exosomes stained with the alternative product (green or red).

      

      Mem Dye-Deep Red and Product “P” (Green and Red) in aqueous solution were analyzed by NTA (nanoparticle tracking analysis) to investigate the generation of aggregates. No aggregation was observed in the experiments with Mem Dyes, although Product “P” (Green and Red) produced dye-to-dye aggregates (100–500 nm size). In Mem Dye-Green, Red, the aggregation of the dye was not confirmed as in Mem Dye-Deep Red.

      Instrument: LM10-HSBFT 14 (Nanosight)

      Commonly used exosomal membrane dye can cause dye aggregation, exhibiting fluorescent spots that are not derived from exosomes. These dyes can also change the functional properties of exosomes while increasing the background imaging.

      The dyes used in ExoSparkler series (Mem Dye-Green, Red, and Deep Red) do not cause aggregation and have little influence on properties of exosomes, allowing a more accurate observation of exosome dynamics.

      •  Our ExoSparkler Exosome Membrane Labelling Kits provide everything from fluorescence labeling to purification

      ExoSparkler series contains filtration tubes available for the removal of dyes unreacted after fluorescence labeling, as well as an optimized protocol for labeling exosomes. Our ExoSparkler series makes it possible to prepare fluorescence labeling of exosomes using the simple procedure.

      

      The filtration tubes used to remove unlabeled dyes in this kit can purify exosomes at a higher recovery rate than gel filtration methods.

      

      •  Mem Dyes have little effect on exosome properties

      NTA (nanoparticle tracking analysis) and zeta potential were measured to determine the changes in exosomes of dye-stained with Mem Dye-Deep Red or Product “P” (green or red) or unstained exosomes. As a result, the Mem-Dye series (green, red, deep red) had little effect on exosome properties.

      Effect of the dyes on the particle size of the exosomes

      Exosomes were stained with Mem Dye-series (green, red, deep red) and Product “P” (green and red) at a dye concentration of 10 µmol/L in DMSO, the NTA (nanoparticle tracking analysis) of the stained exosomes (as 10 µg protein) was measured.

      As a result, Mem Dyes-series did not change number and particle size of the exosomes (bottom left). Conversely, the Product “P” stained exosomes showed the significant changes of particle size and population of the exosomes (bottom right).

      Instrument: LM10-HSBFT 14 (Nanosight)

      Effect of the dyes on the zeta potentials of the exosomes

      Exosomes were stained with Mem Dye-series (green, red, crimson) and Product “P” (green and red) at a dye concentration of 10 µmol/L in DMSO, the zeta potentials of the stained exosomes (as 10 µg protein) were measured.

      As a result, product “P”-stained exosomes have lower zeta potential than Mem Dye-stained.

      Instrument: Zetasizer Nano ZSP (Malvern Panalytical)

      Observe the time-dependent changes in exosome localization

      Exosomes purified by ultracentrifugation (10 µg as protein amount) were stained with Mem Dye-Deep Red (Exosome Membrane Fluorescence Labeling Kit) and added to HeLa cells (1.25×10^4 cells) stained with lysosome staining dye. The fluorescence images were observed after 1 h and 4 h incubation.

      As a result, it was confirmed that the fluorescence puncta (purple) of Mem Dye-Deep Red overlapped with the localization of lysosomes (green) over time (white), and that the localization of exosomes changed in a time-dependent manner.

      Mem Dye-Deep Red (Purple): Ex 640 nm/Em 640-760 nm; Lysosome staining dye: Ex 488 nm/Em 490-540 nm