Abstract: 　Objective To explore the sex difference in proteins between male and female adult worm of Schistosoma japonicum . Methods Two electrophoresis was used to analyse the difference of protein between the male and female adult worm of S. japonicum (Chinese strain). Results Two dimensional electrophoresis analysis revealed that at the site of 43 kDa and an isoelectric point (pI) of 5.60-5.90 the male worm exhibited a band carrying a number of spots and dots, being longer and wider than that exhibited by the female worm. The female worm exhibited 7 specific dots. Conclusion The sex differences in proteins between male and female adult worms of S.japonicum are significant.

Key words: Schistosoma japonicum, two dimensional electrophoresis, proteomics, sex difference