Pausing of mammalian cells by cold exposure, limits and opportunities

The use of mammalian cells for research and for numerous applications could be facilitated significantly if pausing, i.e. reduction and reactivation of cellular activity, could be executed at will without negative effects. Preferably, pausing should be possible at any phase of a cell culture and at any scale of operations. In this communication we report our first observations to pause cell cultures by temperature reduction. Little information is available in the literature on cold exposure of mammalian cells (1). For this study, we took advantage of the availability of stable GFP-transfected CHO cells whose biomass in culture could be fast and noninvasively monitored by a standard fluorescence reader (2).