Apoptosis-reply

darzynk@nymc.edu
Sat, 01 Jul 1995 10:15:46 -0500

Reply to the questions posed by David Bradbury regarding rather
unexpected features of apoptotic cells when analyzed by in situ DNA
strand breaks assay:

Apoptosis can have many atypical features, depending on the cell
type and nature of the inducing agent. Indeed, it is possible to
observe enlarged apoptotic cells, compared to the size of their
normal counterparts. Ocassionally this happens during the sample
preparation - early apoptotic cells flatten more extensively when
cytocentriguged or smeared on slides. Location of the degraded (i.e.
the presence of NA strand breaks) also can be atypical. For example,
we observed that apoptosis of MOLT-4 cells when triggered by protein
kinase inhibitor H7 is characterized by a characteristic "crown-, or
pearl necklace- like" appearance of the degraded DNA, just at
periphery of the extremely flattened nuclei (Traganos et al., Int. J.
Oncol., 2: 47, 1993).
Zbigniew Darzynkiewicz