RE: LDL Endocytosis

Tom Delohery (tdeloher@bigmac.mskcc.org)
Mon, 9 May 1994 19:02:31 +0530

Hello - We used to measure LDL endocytosis using LDL stained with Nile Red
(also available from Mo Pro). The nice thing about Nile Red (NR)
is the emmission depends on the polarity of the lipid environment.
In polar lipids, such as phospholipids in membranes, it's fluorescence
is bright red (>600 nm). In neutral lipids, such as liposomes filled
with triglycerides and cholesterol esters, the fluorescence shifts to
yellow-green. By measuring the ratio of green:red you can normalize
differences due to cell size and NR staining.

I had a user who brought me 20 NR-stained samples, half of which
were incubated for various times with varying concentrations of LDL.
He wanted a blind test to see if I could match the untreated with the
treated. There was absolutely no problem. The Red fluorescence
shifted very little from sample to sample, but the Green increased
substantially for LDL treated cells.

I've also seen some great photographs of LDL treated macrophages
stained with NR.

Sorry this is so late, I've been swamped.

tom d.

--
==============================================================================
 Tom Delohery                           | Internet: tdeloher@bigmac.mskcc.org
 Manager, Flow Cytometry Core Facility  |    Phone: (212) 639-8729
 Memorial Sloan-Kettering Cancer Center |      Fax: (212) 794-4019
==============================================================================
     QUESTION AUTHORITY..............
     on every fundamental precept proposed as an explanation of any
     aspect of reality; because reality is a perception and therefore
     inherently subjective and gaussian in distribution. (possibly Poisson)
     Definately skewed!

Home Page Table of Contents Sponsors Web Sites
CD ROM Vol 2 was produced by 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:(317) 494-0757; FAX (317) 494-0517; Web http://www.cyto.purdue.edu EMAIL robinson@flowcyt.cyto.purdue.edu