Hoechst and Pyronin odd peak

From: Plett, Paul A. (pplett@iupui.edu)
Date: Thu Jul 01 1999 - 13:29:19 EST


Hello flowers

I am posting this question for my lab, not having much expertise with this
stain myself and while the local experts are frolicking at a conference in
Monaco.
Here is the question:
We use Hoechst (for DNA) then Pyronin (for RNA) staining to define
populations within the Go/G1 population by the amount of RNA. Additional
info is that the Pyronin is used at 3.3 uM concentration, a non-toxic
concentration.

Lately we have seen a very odd phenomenon. When cord-blood samples were
stained, the Hoechst single stain gives a normal cell-cycle pattern, but
when the two stains are combined, most of the pyronin staining appears to be
in sub-G0 peak on Hoechst.
Additionally, when the same stain was run on peripheral blood cells, the
stain was normal (i.e. that most of the pyronin stain fell on the G0/G1 peak
and some on the S+G2/M). 

Are there any suggestions or ideas on what may be causing this sub-G0 peak?
Any and all replies are greatly appreciated. 

Artur Plett
IUPUI-Heme/Onc division



This archive was generated by hypermail 2b29 : Wed Apr 03 2002 - 11:53:40 EST