In This Issue

FEATURED NEW PRODUCTS

 
Specific Cytoskeletal Labeling — CellLight™ Cytoskeletal Reagents

 Illuminating Membrane Trafficking — CellLight™ Membrane Trafficking Reagents

 Create Your Own Virtual Cell — Virtual Cell Staining Tool

New Products for Cell &Tissue Analysis
 
Find Antibodies From Invitrogen with our new selection tools


NEW APPLICATIONS


 
Highly Specific In Vivo Molecular Imaging and Cancer Detection

FEATURED NEW PRODUCTS

CellLight™ Cytoskeletal Reagents

what they are
CellLight™ reagents are fluorescent protein–signal peptide fusions that permit accurate and specific targeting to cellular structures, including the cytoskeleton, for live-cell imaging applications, or for fixed-cell analyses following formaldehyde-based fixation.



what they offer

  • Efficiency— >90% transduction of a wide range of mammalian cell lines, including primary cells, stem cells, and neurons
  • Fast—simply mix the BacMam 2.0 reagent with cells, incubate overnight, then analyze
  • Convenient—ready to use, no subcloning required
how they work
Cellular labeling with CellLight™ reagents employs BacMam technology, which uses a modified insect cell baculovirus coupled with a mammalian promoter as a vehicle to efficiently deliver and express genes in mammalian cells. The inability of baculoviruses to replicate in mammalian cells renders them safe as research reagents and provides a transient, footprint-free method to label cells. Unlike expression vectors, BacMam reagents enable titratable and reproducible expression and offer high cotransduction efficiency, enabling multiple BacMam reagents to be used in the same cell.

Live cell imaging

Live-cell imaging of neurons.


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Hippocampal tissue from postnatal day 3 rats was harvested and dissociated in neural culture medium prior to plating onto glial feeder cultures. Undissociated hippocampal tissue was allowed to settle, and the supernatant containing neurons was transferred to a fresh vial. Cell density was determined with the Countess® Automated Cell Counter, and cells were resuspended at 50,000 cells/mL in complete neural culture medium plus mitotic inhibitors. The medium was removed from the glial feeder cultures and replaced with 2 mL of the neural cell suspension. CellLight™ MAP4-RFP (50 µL) was added to the plates, and cells were placed into the cell culture incubator. A complete medium change was performed the following day, and cultures were allowed to mature for 2 weeks before imaging on a DeltaVison® DV Core (Applied Precision, Issaquah, WA), with partial medium changes twice a week. Fluorescence was observed in neurons after 48 hr in culture.
Product
Quantity Cat. No.
CellLight™ Actin-GFP *BacMam 2.0*1 mL
C10582
CellLight™ MAP4-GFP *BacMam 2.0*
1 mL
C10598
CellLight™ MAP4-RFP *BacMam 2.0*1 mL
C10599
CellLight™ Talin-GFP *BacMam 2.0*
1 mL
C10611
CellLight™ Talin-GFP *BacMam 2.0*1 mL
C10612
CellLight™ Tubulin-GFP *BacMam 2.0*
1 mL
C10613
CellLight™ Tubulin-RFP *BacMam 2.0*1 mLC10614
 

CellLight™ Membrane Trafficking Reagents

what they are
CellLight™ reagents provide a simple and effective method for introducing targeted intracellular labels into live cells, enabling unambiguous visualization by fluorescence microscopy of key organelles involved in membrane trafficking.



what they offer

  • Real-time analysis—observe endosomes in live cells
  • Ease of use—one-step protocol
  • Flexibility—compatible with live- or fixed-cell analyses


how they work
BacMam technology is based on the use of an insect cell baculovirus for efficient gene delivery and expression in mammalian cells. The enhanced BacMam 2.0 system greatly expands the efficiency and utility of this gene delivery platform. Cell types previously not compatible with or poorly transduced with BacMam 1.0 can now be labeled with BacMam 2.0, including primary cells (e.g., neurons) and stem cells. This improved performance is due to inclusion of elements that greatly enhance transduction efficiency and expression levels: a pseudotyped capsid protein for more efficient cell entry, and genetic elements that boost expression levels.
 
Live-cell imaging with CellLight™ reagents
Live-cell imaging with CellLight™ reagents and stem cells.

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To create this image, Cascade Biologics® HASMC (human aortic smooth muscle cells) were incubated with CellLight™ Golgi-GFP and CellLight™ Mitochondria-RFP. The following day, cells were stained with Hoechst 33342. Imaging was performed on live cells using a DeltaVision® Core microscope and standard DAPI/FITC/TRITC filter sets.
Product
Quantity Cat. No.
CellLight™ ER-GFP *BacMam 2.0*1 mLC10590
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CellLight™ ER-GFP *BacMam 2.0*1 mLC10591Order Now
CellLight™ Golgi-GFP *BacMam 2.0*1 mL C10592Order Now
CellLight™ Golgi-RFP *BacMam 2.0*1 mL C10593Order Now
    

Virtual Cell Staining Tool

what it is
Explore the fascinating world of cellular imaging with this new online tool. Select different combinations of cellular structures and fluorophores to create your version of the perfectly labeled fluorescent cell!



what it offers

  • Easily find products to label your cell
  • Create and print your cell image
  • Share with your colleagues


how it works
Stain your own cell virtually, using our brand-new cell staining simulation tool to develop reproducible results with many of our signature fluorescent dyes. 

 
Cell staining tool
Virtual Cell Staining Tool

Read More +
Image was created using the new online cell staining simulation tool with Molecular Probes® signature fluorescent dyes.

NEW APPLICATIONS

Highly Specific In Vivo Molecular Imaging and Cancer Detection

It has recently been reported that several xanthene fluorophores readily form H-type dimers (H-dimers) when conjugated with proteins [ACS Chem Biol 4:535–546 (2009)]. H-dimer formation quenches the fluorescent signal, which in turn can be exploited for specific in vivo imaging. The pH-dependent pHrodo™ dye not only uniquely exhibits the ability to form H-dimers but also can be activated by photon-induced electron transfer (PeT).

The avidin–pHrodo™ dye conjugate has been used to visualize tumors with high target-to-background ratios after injection into tumor-bearing mice. A unique advantage of this approach over other molecular imaging methods is that the fluorescent probe is quenched when injected, and is activated only after binding and internalization by the target cancer cells or tissues.

Learn More about pHrodo™ Indicators

 

Fluorescence imaging of peritoneal tumors in mice.
The avidin–pHrodo™ dye conjugate was injected into SHIN3 peritoneal tumor-bearing mice (50 μg, i.p.). One hour after the probe injection, fluorescence endoscopy (A) was performed using the Olympus EVIS ExERA-II CLV-180 system (Olympus Corp., Tokyo, Japan; excitation wavelength, 543/25 nm, emission filter, 597.5/55 nm). After endoscopy the mice were sacrificed, and ex vivo fluorescence spectral imaging (B) was performed on a Maestro In-Vivo Imaging System (CRi, Inc., Woburn, MA; excitation filter, 503 to 555 nm; emission filter, longpass filter over 580 nm). The spectral fluorescence images consisting of autofluorescence spectra and the spectra from the pHrodo™ dye were obtained and then unmixed based on their spectral patterns. Tumors were clearly visualized with low background signal, and the results were consistent with the endoscopy. Images reproduced with permission from Mikako Ogawa and coworkers, National Cancer Institute.
Product
Quantity Cat. No.
pHrodo™ Succinimidyl Ester *amine-reactive*1 mgP36600
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DEPARTMENTS

Buzzworthy

Anti-apoptotic effect of the basic helix-loop-helix (bHLH) transcription factor DEC2 in human breast cancer cells.

Liu Y, Sato F, Kawamoto T et al. (2010) Anti-apoptotic effect of the basic helix-loop-helix (bHLH) transcription factor DEC2 in human breast cancer cells. Genes Cells 15:315–325.

In a study to define the roles of the transcription factors DEC2 and DEC1 in the survival of tumor cells, Liu and colleagues carried out several experiments to alter the levels of DEC2 and DEC1 in the MCF-7 human breast cancer cell line. Following siRNA knockdown of DEC2, cell death was markedly enhanced and nuclear condensation was observed (using the Click-iT® TUNEL Alexa Fluor® 488 Imaging Assay and Hoechst 33258 dye). These observations are consistent with the role of DEC2 as an apoptosis suppressor. In contrast, knockdown of DEC1 did not affect cell survival. Overexpression of DEC2 reduced the amount of cleaved PARP and caspase-8 (induced by TNF-alpha treatment), whereas overexpression of DEC1 increased the levels of these same proteins (with or without TNF-alpha treatment)—again supporting the hypothesis that DEC2 and DEC1 have opposing properties with respect to apoptosis. The authors conclude that the balance between the levels of DEC2 and DEC1 directly translates to the balance of survival of MCF-7 cells.

Product
Quantity Cat. No.
Click-iT® TUNEL Alexa Fluor® 488 Imaging Assay 1 kitC10245
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Hoechst 33258, pentahydrate (bis-benzimide),  FluoroPure™ grade100 mgH21491
Order Now
    

Fibroblast Cells
 

Visualizing the cytoskeleton and Golgi complex in African green monkey kidney fibroblast cells.
COS-7 cells were labeled with Alexa Fluor® 488 phalloidin (green), Alexa Fluor® 350–wheat germ agglutinin conjugate (blue), and propidium iodide (red). Image contributed by Mike Davidson, Florida State University.  




Product
Quantity Cat. No.
Emission Color

Alexa Fluor® 488 Phalloidin300 units Order Now
Propidium Iodide100 mg Order Now
Wheat Germ Agglutinin, Alexa Fluor® 350  conjugate
5 mg
Order Now
 

Tracking Tumor Cell Migration With CellTracker™ Dyes

Molecular Probes® CellTracker™ dyes freely diffuse through the membranes of live cells and, once inside, the action of intracellular esterase converts them to fluorescent forms that survive fixation. Cells labeled in this manner remain viable and fluorescent for days to weeks, even after 5–6 divisions. For cell migration studies, these dyes can be used to follow cells as they migrate through tissue, either artificial or real, and can be multiplexed with functional probes for the simultaneous detection of cell migration and ECM degradation. CellTracker™ dyes have been used to visualize the migration of tumor cells through three-dimensional extracellular matrices, their interaction with stromal fibroblasts, and the simultaneous digestion of the ECM protein collagen IV.


Apoptotic Cell
 

Interaction of tumor spheroids with stromal fibroblasts results in extensive degradation of type IV collagen. HCT116 human colon carcinoma cells were cocultured with human colon fibroblasts prestained with CellTracker™ Orange in reconstituted basement membrane containing DQ™ collagen IV. Extensive proteolysis resulting in fluorescence of DQ™ collagen IV (green) occurs at the site of interaction between the tumor spheroids and the fibroblasts (orange), with yellow regions denoting areas of overlap. Magnification: 40x. Image supplied by Drs. Mansoureh Sameni and Bonnie Sloane, Wayne State University.



Imaging tumor cell migration in vitro. Tumor cells are labeled with CellTracker™ dye and migrate through DQ™ collagen substrate suspended in three-dimensional matrix gel. Green fluorescence indicates the region of collagen degradation by secreted proteases. In this schematic, cells are labeled orange with CellTracker™ Orange dye, and nuclei are stained blue with Hoechst 33342.


Product
Quantity Cat. No.
CellTracker™ Blue CMAC
5 mg
C2110Order Now
CellTracker™ Green CMFDA20 x 50 mgC7025Order Now
CellTracker™ Orange CMTMR 1 mgC2927Order Now
CellTracker™ Orange CMRA20 x 50 mgC34551Order Now
CellTracker™ Red CMTPX20 x 50 mgC34552Order Now
DQ™ Collagen, type IV from human placenta, fluorescein conjugate1 mgD12052Order Now
Hoechst 33342, 10 mg/mL solution in water10 mLH3570Order Now
    

Labeling Chemistry Selection Tool—NEW!

Quickly find the best reactive dye or label for your experiment. Whether you are labeling proteins and antibodies for immunofluorescence, nucleic acids for in situ hybridization, or lipids for membrane studies, this tool will help you find the right conjugation product.

Learn More about the Labeling Chemistry Selection Tool


Molecular Probes® The Handbook

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