Principle of detecting apoptosis with Annexin V

Yashpal Agrawal (yagrawal@messi.uku.fi)
Mon, 21 Oct 1996 08:25:21 +0300 (WET)

Hi every body,
Annexin V staining is becoming popular for detecting
apoptotic cells. I understand this is because Annexin V stains membrane
phosphatidylserine (PS), which is a marker of apoptotic cells. Is it this
simple ?. Am I understanding the principle correctly ?

1. How does one exclude that the surface PS that one is detecting is not
the normal component of cell membrane ?
(I know non-nucleated cells (red blood cells) express PS, and also
many nucleated cells (Cd34+) express PS).

2. If an increase/decrease in Annexin V staining occurs, how can it be
excluded that PS levels have not been up/down regulated, in contrast to
assuming apoptosis as the cause. Membrane phospholipids flip-flop all the
time in response to various modifiers.

Please could some one enlighten me. I am sure I have misunderstood the
Annexin V assay.

Thanks,
Yash Pal Agrawal
Kuopio, Finland
yagrawal@messi.uku.fi

Home Page Table of Contents Sponsors E-Mail Archive Web Sites

CD-ROM Vol 3 was produced by Monica M. Shively and other staff at the Purdue University Cytometry Laboratories and distributed free of charge as an educational service to the cytometry community. If you have any comments please direct them to Dr. J. Paul Robinson, Professor & Director, PUCL, Purdue University, West Lafayette, IN 47907. Phone: (765)-494-0757; FAX(765) 494-0517; Web http://www.cyto.purdue.edu , EMAIL cdrom3@flowcyt.cyto.purdue.edu