Protein antigens in the cyst fluid of Taenia saginata cysticerci.

Taenia saginata cyst fluid proteins from 4, 8, 12 and 16-week-old cysticerci were analysed by a combination of direct 125I radio-isotope labelling, immunoprecipitation using a panel of sera from infected cattle infected with T. saginata and SDS-PAGE. Protein antigens of 12, 14, 16, 20 and 26 kDa were identified in all of the cyst fluids examined. These were immunogenic and were precipitated by serum taken from cattle from 8 weeks after infection onwards and were therefore considered to be of diagnostic potential. A 185 kDa protein antigen found only in the cyst fluid of 4-week-old cysticerci and a 43 kDa protein antigen first detected in cyst fluid from 8-week-old cysticerci were also identified but were considered to be of more limited diagnostic potential due to their restricted presence. An apparently non-immunogenic 67 kDa protein, found in all the cyst fluids examined, may have been host serum albumin.