細(xì)胞凋亡是胚胎發(fā)育和維持組織穩(wěn)態(tài)的正常生理過(guò)程。凋亡過(guò)程具有一定的形態(tài)學(xué)特征，包括質(zhì)膜不對(duì)稱(chēng)和附著的喪失、細(xì)胞質(zhì)和細(xì)胞核的凝聚以及核小體間DNA的分裂。質(zhì)膜的丟失是最早的特征之一。在凋亡細(xì)胞中，細(xì)胞膜磷脂磷脂酰絲氨酸(PS)從質(zhì)膜的內(nèi)葉轉(zhuǎn)移到外葉，從而使PS暴露于細(xì)胞外環(huán)境。膜聯(lián)蛋白V是一種35-36 kDa的Ca2+依賴(lài)性磷脂結(jié)合蛋白，對(duì)PS具有高親和力，并與暴露于PS的細(xì)胞結(jié)合。膜聯(lián)蛋白V可偶聯(lián)到熒光色素，包括藻紅蛋白(PE)。這種格式保留了對(duì)PS的高親和力，因此可以作為流式細(xì)胞術(shù)分析細(xì)胞凋亡的敏感探針。由于PS的外化發(fā)生在細(xì)胞凋亡的早期階段，PE Annexin V染色可以比基于細(xì)胞核變化(如DNA斷裂)的檢測(cè)更早地識(shí)別細(xì)胞凋亡。
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 Phycoerythrin (PE). 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, PE Annexin V staining can identify apoptosis at an earlier stage than assays based on nuclear changes such as DNA fragmentation.
Components
Part No.
Description
Size
51-65875X
PE Annexin V
0.5 mL (1 ea)
51-68981E
7-AAD
2 mL (1 ea)
51-66121E
10X Annexin V Binding Buffer
50 mL (1 ea)
PREPARATION AND STORAGE
Store undiluted at 4°C and protected from prolonged exposure to light. Do not freeze.
PRODUCT NOTICES
1. This reagent has been pre-diluted for use at the recommended Volume per Test. We typically use 1 × 10^6 cells in a 100-μl experimental sample (a test).
2. Source of all serum proteins is from USDA inspected abattoirs located in the United States.
3. 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.
4.Please refer to www.bdbiosciences.com/pharmingen/protocols for technical protocols.