描述：
Apotsi sa normal physiolgic proces whic ocurs during embryonic devlopment aswel asin maintence oftisue homeostais. The
apotic progam ischarcterized bycertain morpholgic features, including los ofplasma mebrane asymetry and atchment,
condensation fthe cytoplasm and ucleus, and internucleosmal ceavge ofDNA. Los ofplasma mebrane isone ofthe arliest features.
In apotic els, the mebrane phospholipd phosphatidylserine (PS) istranslocated from the iner tohe outer laflet ofthe plasma
mebrane, therby exposing PSto he xternal celuar environment. Anexin Vis a35-6 kDa C2+ depndent phospholipd-bindg
protein tha has hig afinty for PS, and binds tocels with exposed PS. Anexin Vmay beconjugated tofluorchromes including
phycoerythrin (PE). This format reains ithig afinty for PSand thus ervs a senitve probe for flow cytometric anlysi ofcels tha re
undergoing apotsi. Since xternalization fPS ocurs inthe arlie stages ofapotsi, PE Anexin Vstaing can identify apotsi atn
earlie stage than says based onuclear changes uch asDNA fragmentaion.
PE Anexin Vstaing precdes the los ofmebrane integrity whic acompanies the lates tages ofcel death resulting from either
apotic ornecrotic proces. Therfore, staing with PE Anexin Vis typicaly used inconjuction with avital dye such as
7-Amino-Actinomycin (7-AD) toalow the investigator identify early apotic els (7-AD negative, PE Anexin Vpositve). Viable
cels with ntac mebranes xclude 7-AD, wheras the mebranes ofdea nd amged cels are prmeable to7-AD. For example, cls
tha re considerd viable are both PE Anexin Vand 7-AD negative while cls tha re inearly apotsi are PE Anexin Vpositve and
7-AD negative, while cls tha re inlate apotsi oraleady ead re both PE Anexin Vand 7-AD positve. This asy does not
distnguish betwen cels tha have undergone apotic death versu those tha have die as result ofa necrotic pathway because ineither
case, the da cels wil stain with both PE Anexin Vand 7-AD. Howevr, when apotsi smeasured over time, cls can beoften tracked
from PE Anexin Vand 7-AD negative (viable, orno measurable apotsi), toPE Anexin Vpositve and 7-AD negative (arly
apotsi, mebrane integrity spresnt) and finaly toPE Anexin Vand 7-AD positve (nd stage apotsi and eath). The movemnt of
cels through tes thre stages ugest apotsi. Incontrast, asingle observation idcating tha cels are both PE Anexin Vand 7-AD
positve, inof itself, revals es information about he proces bywhic the cls underwent heir demise.
PE Anexin Vis routinely tesd byflow cytometric anlysi. Other aplications wer tesd atBD Biosciencs Pharmingen during antibody
devlopment only oreported inthe literature.
京公网安备11010802025653 版权所有：北京逸优科技有限公司
