BrdU versus PI

Phil Marder, MC625, Ext 6-5071, Drop 0444 (MARDER_PHILIP@LILLY.COM)
12 Aug 1992 14:15:18 -0500 (EST)

We have recently been studying the mechanism of some novel oncolytic agents
in my laboratory and have observed an inconsistency in some acquired flow
cytometric data. When the novel compound is run in a typical propidium iodide
stained cell cycle analysis , an obvious strong accumulation of S-phase cells
is observed. When the same compound is run at the same concentrations
(etc......) in a BrdU incorporation/antibody flow detection method, no such
S-phase accumulation is observed!
Can anyone give me some possible explanations for what is really happening
here? Can there be structural changes in DNA that mimic S-phase accumulations?
Which method is a more reliable indicator of the effects noticed?

Thanks,
Phil Marder
Lilly Research Labs

From: MARDER PHILIP (MCVAX0::MARDER)

To: FOREIGN TRANSPORT ADDRESSEE (MCDEV1::IN%"cytometry@flowcyt.cyto.purdue.edu")
cc: MARDER PHILIP (MCVAX0::MARDER)