Figure 3

Cleavage of cytokeratin 18 in SC-1–induced apoptosis. Immunohistochemical staining of cytospins reveals that 24 hours after the induction of apoptosis, cleavage of cytokeratin 18 starts (b), and after 48 hours, apoptotic bodies are released from the cells (c). In Panel a, a nonapoptotic cell is shown (magnification, ×400). The overview shows a low amount of apoptosis in uninduced cells (d), whereas SC-1–induced apoptosis begins after 24 hours (e). After 48 hours, approximately 30% have undergone apoptosis as shown by cytokeratin 18 cleavage (f) (magnification, ×400).