Objective: To explore the apoptosis and its induction in S. japonicum.
Methods: The eggs and adult cells of S. japonicum were isolated. The adult cells were incubated with H2O2, dexamethasone and cyclosporin A, cyclosporin A vehicle solution, respectively in order to initiate the apoptosis. The eggs were treatd at 4 degrees C, 37 degrees C and 42 degrees C, respectively for induction of apoptosis. The occurrence of apoptosis was supervised by agarose gel electrophoresis and in situ end labelling.
Results: DNA ladder-band characteristic of apoptosis appeared in the cells of adult worms after incubated with H2O2, dexamethasone or cyclosporin A and the eggs treated at 42 degrees C, whereas no DNA ladder band was found in other control groups. In situ end labeling revealed that the positive fluorescence could be seen in the cells incubated with H2O2, dexamethasone or cyclosporin A and few nuclei in the control group and cyclosporin A vehicle solution group appeared positive fluorescence.
Conclusion: Apoptosis in the cells of S. japonicum adults and eggs induced by chemical or physical agents was observed.