Related Experiment Videos
Cysticercosis: identification and cloning of protective recombinant antigens
K Manoutcharian1, G Rosas, M Hernandez
1Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México.
Abstract:
We describe the cloning and the evaluation of the protective capacity of 5 recombinant antigens expressed during the cysticercus stage of both Taenia crassiceps and Taenia solium. A cDNA library was constructed in bacteriophage lambda ZAP using mRNA isolated from larvae of T. crassiceps of the ORF strain. The recombinant phage library was screened with polyclonal antibodies against 56- and 74-kDa protective antigen fractions. This screening identified 13 recombinant clones, 5 of which were also strongly recognized by pooled sera from pigs experimentally infected with T. solium. The native antigens are proteins of 56 (clones KETcl, 4, 7) and 74 and 78 kDa (clones KETc11, 12) of T. crassiceps cysticerci. Vaccination experiments using these 5 recombinant clones against murine cysticercosis point to the relevance of KETcl, 4, 7, and 12 in host protection, whereas immunization with the clone KETc11 does not modify the parasite load in females and facilitates the parasitosis in males. We report here the DNA and the deduced amino acid sequence (100 amino acids) of the first protective antigen (KETc7) of potential interest for T. solium pig cysticercosis prevention.
Insights
Researchers identified five recombinant antigens from Taenia crassiceps and Taenia solium cysticerci. Four antigens (KETcl, 4, 7, and 12) show protective capacity against cysticercosis, with KETc7 being a key target for pig parasite prevention.
Area of Science:
- Parasitology
- Molecular Biology
- Immunology
Background:
- Cysticercosis, caused by Taenia solium larvae, poses a significant threat to human and porcine health.
- Developing effective vaccines against cysticercosis requires identifying and characterizing protective antigens from the parasite's larval stage.
Purpose of the Study:
- To clone and evaluate the protective potential of recombinant antigens from the cysticercus stage of Taenia crassiceps and Taenia solium.
- To identify key antigens for developing a vaccine against Taenia solium cysticercosis in pigs.
Main Methods:
- Construction of a cDNA library from Taenia crassiceps larvae.
- Screening the library using antibodies against protective antigen fractions and pooled sera from infected pigs.
- Vaccination experiments in mice using recombinant antigens to assess protective capacity.
Main Results:
- Five recombinant clones (KETcl, 4, 7, 11, and 12) expressing antigens of 56, 74, and 78 kDa were identified.
- Clones KETcl, 4, 7, and 12 demonstrated significant protective capacity against murine cysticercosis.
- Clone KETc11 showed no protective effect and even exacerbated the infection in male mice.
- The DNA and amino acid sequence of KETc7, a protective antigen, were determined.
Conclusions:
- Recombinant antigens KETcl, 4, 7, and 12 are promising candidates for a Taenia solium cysticercosis vaccine.
- KETc7 represents the first characterized protective antigen with potential for preventing pig cysticercosis.
- Further research is needed to elucidate the differential effects of KETc11.