Cell cycle kinetics of insect cell cultures compared to mammalian cell cultures.

Cell cycle kinetic of lepidopteran cell lines Sf9 (Spodoptera frugiperda) and IZDMb0503 (Mamestra brassicae) were investigated and compared to mammalian cell cycle distributions. The resting phase (G0) of mammalian cells is characterized by a 2c-DNA content whereas G0-phase of insect cell lines is characterized by a 4c-DNA content. Flow cytometric data in combination with growth curves of partially synchronized and asynchronously growing cells proved the existence of this phenomenon. Kinetics of cells labeled by the thymidine analog on 5-bromo-2'-deoxyuridine supported these results, which now render the possibility of applying cell cycle analysis in fermentation technology of insect cells.