Study On The Protein Antigen Characteristics Of Schistosoma Japonicum At Different Life Stages

objective To analyze the protein constituents and their antigen characteristics of Schistosoma japonicum at different life stages,which were obtained by chemical cleavage,in order to supply theory evidence to screening application valuble antigen elements. To explore the optimum condition for gathering schistosoma japonicum eggs purified that can remain higher purity , complete structure so as to study eggs bionomics further.Methods The female,male worms were segregated by low tempareture disposal,the internal eggs of female worms were removed by freeze thawing(-30℃) three times; The fractions of the soluble cercaria antigen(SCA),soluble adult worm antigen (AWA–female,male) and soluble egg antigen (SEA ) were prepared chemically,and separated by SDS—PAG, The distribution ranges of relative molecular weight of these fractions were statistically analyzed.The sera of rabbits were collected at different time after the rabbits were infected with cercaria of Schistosoma japonicum.Soluble cercaria antigen(SCA),soluble adult worm antigen (AWA–female,male))and soluble egg antigen (SEA )were immunologic analyzed by Western blotting with rabbits'sera of different time of post—infection. The eggs of Schistosoma japonicum were collected by repetitive sievings followed by trypsin digestion and centrifugation,and compaired with those eggs obtained by floatation.Results the main results were given as follows:(1)The fractions of SEA consists of 52 bands,( molecular weight chiefly ranging among 61.0kD～97kD,19.0kD～35.1kD), AWA-M 48 bands( among 84.2kD～97.2kD,61.0kD～76.8kD,48.4kD～55.6kD,27.8kD～35.1kD, AWA-f 40 bands(25.6kD～27.6kD,27.8kD～35.1kD,61.0kD～67.2kD ),SCA about 6 bands(146kD,121kD,78.1kD,66.8kD,55.6kD,36.6kD) . (2) In Western blotting,the band of 78.1kD of SCA recognized by the rabbits sera of 6-week post—infection,the bands of 58.5kD,55.8kD,33.6-39.8kD of AWA-m reacted with the infected rabbits sera strongly, the bands of 55.8kD,26.1-33.3kD of AWA-f reacted with the infected rabbits sera strongly, the bands of 109.5kD,105.0kD,78.1-88.7kD,68.9kD,36.6kD,27.3kD of SEA reacted with the infected rabbits sera strongly.(3)On the optimum condition of enzyme digestion ,the eggs with 99 per purity were obtained .The isolated eggs remained intact and the rate of recovery was significantly increased comparatively.Conclusions The differences of protein constituents of Schistosoma japonicum are obvious between sexes, and among the life stages as well.The bands of 78.1KD of SCA, 58.5kD,55.8kD,26.1-33.3kD,33.6-39.8kD of AWA, 109.5kD,105.0kD,78.1-88.7kD,68.9kD,36.6kD,27.3kD of SEA might have potential diagnosis and prevetion value for Schistosomiasis .Comparatively, enzyme digestion could get a better effect when purifying Schistosoma japonicum eggs.