Abstract
In most cells, vaccinia virus (VACV) infection is considered to cause a lytic cell death, an equivalent of necrosis. In this paper, we have further analyzed the type of cell death in VACV-infected cells HeLa G and BSC-40.
In a cell-based flow cytometric assay, we showed a specific activation of caspase-2 and 4 in HeLa G and BSC-40 cells infected with VACV, strain WR. The actual activity of the two caspases, but also of caspase-3, was then confirmed in lysates of infected HeLa G, but not in BSC-40 cells.
PARP cleavage, as well as morphological features of apoptosis and/or activity of the executioner caspase-3 in situ were found increased only in infected HeLa G cells. Finally, vaccination strains Dryvax and Praha were found to induce apoptosis in both HeLa G and BSC-40 cells, as characterized morphologically and by PARP cleavage.
These findings may be important for understanding the differences in VACV-host interactions and post-vaccination complications in different individuals.