ABSTRACT
In the past, time-lapse studies have demonstrated that HeLa cells (1,2) and
mouse L cells (3) undergo postmitotic death after the cells divided one or more
times; the death processes were associated with trapping in mitosis, fusion of
daughter cells, giant cell formation, and death during interphase that was clas-
sified as pyknosis or necrosis. When these studies were conducted, apoptosis had
not been identified. Also, with an aerial photographic camera that was used for
visualizing a large number of cells in order to construct pedigrees (3), individual
cells could not be adequately visualized to discern morphological alterations that
could be related to the ultimate fate of the cells. Attempts have been made to
develop time-lapse systems using multiple fields (4,5) at sufficient magnification
so that progeny from one or two cells in each field at the time of irradiation could
be followed as a colony of approximately 50 cells developed. Retrieval of the
information was very complicated and time consuming, however. For informa-
tion in this chapter, we have used computerized video time lapse (CVTL) (6) for
analyzing (7) the fates of individual cells and their progeny at 200 in about 50 microscopic fields that are followed for as long as four to six days.
