Mummified Hodgkin cells and apoptosis. Authors' reply

✍ Scribed by Lorenzen, Johann; Thiele, Juergen; Fischer, Robert

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 22 KB
• Volume: 185
• Category: Article
• ISSN: 0022-3417
• DOI: 10.1002/(sici)1096-9896(199805)185:1<116::aid-path56>3.0.co;2-c

✦ Synopsis

The study by Lorenzen et al. 1 is worthy of note, since the mummified cells of Hodgkin's disease (HD) have long remained an enigma, being loosely considered as degenerating Hodgkin-Reed-Sternberg (HRS) cells.

In our studies on cell death in HD, 2,3 we have reached conclusions about mummy cells which are similar to those of the authors. We found that mummy cells did not show DNA fragmentation (by the ApopTag assay). However, although the electron microscopic (EM) features of these cells were similar to those found by Lorenzen et al., 1 we were impressed by the swollen mitochondria which imparted to these cells the appearance of 'dark cells'. Nonetheless, we agree with the authors on the significance of this phenomenon. We are dealing with irreversibly damaged cells, probably showing an atypical form of apoptosis, perhaps para-apoptosis.

On the other hand, we were able to demonstrate apoptotic cells which were strongly reactive by in situ end labelling of DNA fragments. These cells were interpreted as apoptotic HRS cells, based on their size, on their positivity by CD15 immunostaining, and most importantly, on their EM features.

The discrepancy noted may be due to the different methods used, including fixation. In our hands, DNA is less well preserved in picric acid-based fixatives.