GFP-expressing mammalian cells for fast, sensitive, noninvasive cell growth assessment in a kinetic mode

This study correlates the fluorescent signal from stable recombinant CHO ce ll lines expressing the green fluorescent protein (GFP) at high levels with biomass or cell number, extending the use of fluorescent proteins to appli cations and assays where cell growth rates are important. Using a standard fluorometer, growth of these cells can be quantified noninvasively in multi well plates, and because signals are obtained without preparation, the same culture samples can be measured repeatedly. Even with a small relative cha nge in biomass, the specific growth rate can be determined in a few hours. The dynamics of cell populations can now be studied with high sensitivity, low error rate, and minimum sample preparation. (C) 1999 John Wiley & Sons, Inc.