Learn More
Invitrogen™ eBioscience™ Annexin V Apoptosis Detection Kits
Description
Includes
- Annexin V-FITC protein
- Binding Buffer (4x)
- Propidium Iodide (20 ug/mL)
Easily distinguish cells undergoing early and late apoptosis with eBioscience and Annexin V Apoptosis Detection kits for flow cytometry analysis. These kits utilize viability dye-conjugated annexin V to label phosphatidylserine (PS), an early marker of apoptosis, on the extracellular membrane. In late-stage apoptosis, as cell integrity is lost, both annexin V and the viability dye traverse and bind PS on the interior of the plasma membrane.
In early-stage apoptosis, the plasma membrane excludes viability dyes such as propidium iodide (PI), 7-AAD, or fixable viability dyes such as eFluor 450. These cells will stain with annexin V but not a viability dye, thus distinguishing cells in early apoptosis. However, in late-stage apoptosis, the cell membrane loses integrity, thereby allowing annexin V to also access PS in the interior of the cell. A viability dye can be used to resolve these late-stage apoptotic and necrotic cells (annexin V, viability dye-positive) from the early-stage apoptotic cells (annexin V positive, viability dye-negative).
Current viability stains available with the eBioscience Annexin V Apoptosis Detection kits include FITC, eFluor 450, allophycocyanin (APC), phycoerythrin (PE), PE-cyanine7, and biotin.
Specifications
Specifications
| Description | eBioscience Annexin V-FITC Apoptosis Detection Kit |
| Quantity | 100 Tests |
| Product Type | Apoptosis Detection Kit |
| Content And Storage | • Binding Buffer (4X), 1 bottle (50 mL) • rh Annexin V-FITC, 1 vial (0.5 mL) • Propidium Iodide (20 μg/mL), 1 vial (1.8 mL). 2°C to 8°C. Avoid temperature fluctuations. |
| Excitation/Emission | 488, 535/520, 617 |
| Shipping Condition | Wet Ice |
| Conjugate | FITC, Propidium Iodide |
| For Use With (Equipment) | Flow Cytometer |
Frequently Asked Questions (FAQs)
Annexin V binding of phospholipids is not species-specific. In the presence of millimolar concentrations of Ca2+, Annexin V binds to several phospholipids, but exhibits the highest affinity for phosphatidylserine. This feature is useful for screening cells undergoing apoptosis. Phosphatidylserine is usually distributed on the inner leaflet of the lipid bilayer, but when cells start to undergo apoptosis, the phosphatidylserine moves to the outer leaflet. The translocation of phosphatidylserine to the outer leaflet makes it available for Annexin V staining. Normal, intact cells will not stain with Annexin V, while cells undergoing apoptosis will be.
Annexin V staining can be visualized by fluorescence microscopy or flow cytometry using conjugates such as Annexin V-FITC, or Annexin V-biotin in conjugation with a streptavidin-conjugated fluorophore. It is important to note that experiments with Annexin V require that the cells under study are live cells with intact membranes. It is not suitable for use with fixed cells as the membrane develops holes during the fixation process, making the phosphatidylserine on the inner face of the membrane accessible for Annexin V binding. For similar reasons, this product is also not suitable for use with tissue sections. Because necrotic cells also have numerous membrane breaches, these cells are also often stained with Annexin V. A quick way to differentiate apoptotic from necrotic cells is with a double staining regime using Annexin V-FITC (green fluorescence) and the DNA staining dye propidium iodide (red fluorescence). Propidium iodide requires membrane breaches in order to gain access to the cell nucleus.
Using the Annexin V-FITC/propidium iodide double staining regime, the following staining patterns are observed with apoptotic and necrotic cells:
1. Cells that are normal will not stain with either Annexin V-FITC or propidium iodide (indicating no phosphatidylserine on the surface and no holes in the membrane).
2. Cells that are starting to undergo apoptosis will stain with Annnexin V-FITC only (indicating phosphatidylserine on the surface but no holes in the membrane).
3. Cells that are in late apoptosis and necrotic cells will stain with both Annexin V-FITC and with propidium iodide (indicating that we cannot tell where the phosphatidylserine is located and that there are holes in the membrane).
Phosphatidylserine is an ubiquitous membrane component among mammalian species; therefore, we believe that Annexin V has utility in monitoring apoptosis with any mammalian-derived cell line. One report (O'Brien et al., 1997) has even indicated its utility in monitoring apoptosis with plant cells. Dive, C., C.D. Gregory, D.J. Phipps, D.L. Evans, A.E. Milner, and A.H. Wyllie (1992) Analysis and discrimination of necrosis and apoptosis (programmed cell death) by multiparameter flow cytometry. Biochem. Biophys. Acta 1133:275-285. Koopman, G., C.P.M. Reutlingsperger, G.A.M. Kuitjen, R.M.J. Keehnen, S.T. Pals, and M.H.J. van Oers (1994) Annexin V for flow cytometric detection of phosphatidylserine expression on B cells undergoing apoptosis. Blood 84:1415-1420. O'Brien, I.E., C.P. Reutelingsperger, and K.M. Holdaway (1997) Annexin-V and TUNEL use in monitoring the progression of apoptosis in plants. Cytometry 29(1):28-33.
Yes, eFluor 450-conjugated antibodies are compatible with eBioscience Annexin V Apoptosis Detection kits.
By clicking Submit, you acknowledge that you may be contacted by Fisher Scientific in regards to the feedback you have provided in this form. We will not share your information for any other purposes. All contact information provided shall also be maintained in accordance with our Privacy Policy.