FIG. 4.

In vitro analysis for apoptosis. Cells infected with sense p21 adenovirus, antisense p21 adenovirus, or PBS only (mock) for 2 days were stained with acridine orange and observed by fluorescence microscopy (a and d) HeLa and C33A cells infected with sense p21 adenovirus, respectively; (b and e) HeLa and C33A cells infected with antisense p21 adenovirus, respectively; (c and f) HeLa and C33A cells without virus infection (mock infected), respectively. The apoptotic bodies are indicated by arrowheads in panels a and d.