Abstract: 　Objective To study the methods of in vitro proliferation and passage cultivation of the cells of Schistosoma japanicum cercariae. Methods Between 5 000 and 10 000 cercariae of Schistosoma japonicum were collected under aseptic condition and placed into RPMI 1640 medium containing 10% fetal bovine serum. The cercariae were disrupted swiftly using a tissue tearor, and the disrupted material was incubated for 30 min in 250 U crab collagenase at 26℃. After centrifugation, the enzyme solution was removed, and modified RPMI 1640 medium was added containing penicillin (100 U/ ml), streptomycin (0.1 mg/ ml), and amphotericin B (0.25 μg/ ml), and certain amount of cell growth enhancing material. When adhesion cells proliferated and grew fully on the bottom, subculture was in progress according to 1:2 split ratio. Cells cultivated by 5 passages were used to detect the specific antibody in sera of patients with chronic schistosomiasis through ELISA. Results On the 3rd day of primary cultivation, bright cells, both individual and clustered, were seen around the disrupted cercariae. A monolayer of cells formed on the 10th day. Adhesion cells grew fully on the bottom and subculture was in progress on the 14th day. Cells were found to grow evenly in passage cultivation, within every 7-14 days another passage could be made. Using cells of the fifth passage cultivation as antigen, the antibody positive rate was 90.3% in patients with chronic schistosomiasis and the false positive rate was 6.7% in healthy controls. Conclusion The in vitro passage cultivation of S. japonicum cercaria cells has been successful to the 5th generation and the cultured material could be used in the immunological research.

Key words: Schistosoma japonicum, cercaria, cell passage cultivation