CFSE doesn't work with HSC in 7 Day culture - CFSE doesn't show distinct peaks for each generation. Why? (Jun/16/2011 )

Hey guys,

I am using CFSE staining for freshly isolated hematopoietic stem cells (HSC) to track cell divisions/proliferation. The problem is, after 7 days of culture I cannot see distinct peaks for the genereations.
You can compare the result here:

http://dl.dropbox.com/u/14232908/CFSE%20Day%200%20and%20Day%207%20HSC.pptx

So there are several possible reasons for this result. Obviously, the staining itself worked, because the peak is going to the left. But the cell divisions are interfering with each other. So I might have seeded the cells in a too high density? There is no description that CFSE should not work for a high cell number.

Has anybody experience with CFSE?

Thanks
Cerise

A very late reply..did you stimulated your HSC to proliferate_? and with which cytokines?