Annexin V Cy5.5 100Tst

• 产品编号：BD-559935      品牌：BD-Pharmingen       原厂货号：559935
• 产品分类：生化和细胞分析 > 标签、标记试剂盒 > 生物偶联物 > Annexin V
• 应用分类：

描述：

Apoptosis is a normal physiologic process which occurs during embryonic development as well as in maintenence of tissue homeostasis. The
apoptotic program is characterized by certain morphologic features, including loss of plasma membrane asymmetry and attachment,
condensation of the cytoplasm and nucleus, and internucleosomal cleavage of DNA. Loss of plasma membrane is one of the earliest features.
In apoptotic cells, the membrane phospholipid phosphatidylserine (PS) is translocated from the inner to the outer leaflet of the plasma
membrane, thereby exposing PS to the external cellular environment. Annexin V is a 35-36 kDa Ca2+ dependent phospholipid-binding
protein that has a high affinity for PS, and binds to cells with exposed PS. Annexin V may be conjugated to fluorochromes including Cy5.5.
This format retains its high affinity for PS and thus serves as a sensitive probe for flow cytometric analysis of cells that are undergoing
apoptosis. Since externalization of PS occurs in the earlier stages of apoptosis, Cy5.5 Annexin V staining can identify apoptosis at an earlier
stage than assays based on nuclear changes such as DNA fragmentation.
Cy5.5 Annexin V staining precedes the loss of membrane integrity which accompanies the latest stages of cell death resulting from either
apoptotic or necrotic processes. Therefore, staining with Cy5.5 Annexin V is typically used in conjunction with a vital dye such as propidium
iodide (PI) or 7-Amino-Actinomycin (7-AAD) to allow the investigator to identify early apoptotic cells (7-AAD negative, Cy5.5 Annexin V
positive). Viable cells with intact membranes exclude 7-AAD, whereas the membranes of dead and damaged cells are permeable to 7-AAD.
For example, cells that are considered viable are both Cy5.5 Annexin V and 7-AAD negative while cells that are in early apoptosis are Cy5.5
Annexin V positive and 7-AAD negative, while cells that are in late apoptosis or already dead are both Cy5.5 Annexin V and 7-AAD positive.
This assay does not distinguish between cells that have undergone apoptotic death versus those that have died as a result of a necrotic pathway
because in either case, the dead cells will stain with both Cy5.5 Annexin V and 7-AAD. However, when apoptosis is measured over time, cells
can be often tracked from Cy5.5 Annexin V and 7-AAD negative (viable, or no measurable apoptosis), to Cy5.5 Annexin V positive and
7-AAD negative (early apoptosis, membrane integrity is present) and finally to Cy5.5 Annexin V and 7-AAD positive (end stage apoptosis and
death). The movement of cells through these three stages suggests apoptosis. In contrast, a single observation indicating that cells are both
Cy5.5 Annexin V and 7-AAD positive, in of itself, reveals less information about the process by which the cells underwent their demise.
Cy5.5 Annexin V is routinely tested by flow cytometric analysis. Other applications were tested at BD Biosciences Pharmingen during
antibody development only or reported in the literature.

原厂资料：

注意事项：

1.Since applications vary, each investigator should titrate the reagent to obtain optimal results.
2.Caution: Sodium azide yields highly toxic hydrazoic acid under acidic conditions. Dilute azide compounds in running water before
discarding to avoid accumulation of potentially explosive deposits in plumbing.
3.Store undiluted at 4°C and protected from prolonged exposure to light. Do not freeze.