ELISA-assay for Pig Taenia solium Cysticercosis by using T18 recombinant antigen

Cysticercosis is caused by infection with the larval stage of tapeworm parasite Taenia solium. This zoonose is a major public health issue with high prevalence in Madagascar, around 21% and 7% to 20% respectively in swine and human. ELISA and Enzyme-linked Immuno-electro Transfer Blot (EITB) remained the main laboratory serological diagnostic tools available in the island. Four native glycoproteins are recognized by antibodies in a majority of sera from patients with cysticercosis and a similar pattern seems to be present in infected pigs. For a better management of this disease in Madagascar, the aim of this study is to set-up and validate the one majority glycoprotein antigen T18 (18KDa) for diagnosis test of pig cysticercosis, produced as recombinant protein.

Using a cDNA library prepared from T. solium cysticerci obtained from different regions of Madagascar, we first analyzed the polymorphism of the T18 gene. Then, gene was cloned into the pMAL-c2X plasmid for expression as an N-terminal maltose-binding protein (MBP) fusion protein and C-terminal hexa-His tagged protein. Product protein was then validated by ELISA test of pig sera.

Preliminary results show a strong conservation of T18 gene. And indeed larger amounts of soluble recombinant protein were obtained from these antigen. T18 recombinant-ELISA present 70% of sensitivity and 100% of specificity.