Improvement of the synthetic tri-peptide vaccine (S3Pvac) against porcine Taenia solium cysticercosis in search of a more effective, inexpensive and manageable vaccine.

Vaccination of pigs may curtail Taenia solium transmission by reducing the number of cysticerci, the precursors of adult intestinal tapeworms in humans. Several antigen preparations induce protection against porcine cysticercosis in experimental settings but only one subunit vaccine (S3Pvac) has been tested and proved effective in the field against naturally acquired disease. Besides improving of the vaccine's effectiveness, significant reductions in production costs and in the logistics of its administration are necessary for the feasibility of nationwide control programs. This review highlights the development of several versions of S3Pvac aimed to increase effectiveness, reduce costs and increase feasibility by novel delivery systems and alternative routes of administration.

Recombinant bacteriophage-based multiepitope vaccine against Taenia solium pig cysticercosis.

The aim of this study was to test the capacity of recombinant phages to deliver antigens for vaccination against porcine cysticercosis. Thus, three peptides (KETc1, KETc12, GK1) and a recombinant antigen KETc7, previously proven to induce high levels of protection against pig cysticercosis, were expressed on the surface of the M13 bacteriophage at multiple copies. The pool of these four recombinant phages induced high levels of protection against an experimental murine cysticercosis. The immunogenicity of the phage vaccine preparation was therefore, tested in pigs, the natural host of Taenia solium. Subcutaneous or oral vaccination with these phages induced antigen-specific cellular immune responses in pigs. Preliminary data also points to the protective capacity of this recombinant phage vaccine against pig cysticercosis. The immunogenicity of these recombinant phages, together with the low cost of their production, make them a realistic candidate to be tested in pigs as an anti-cysticercus phage vaccine for field trials. This is the first report describing the application of a filamentous bacteriophage as a vaccine in large animals such as pigs, the only intermediate hosts of T. solium, a parasite of major medical importance in developing countries. The potential application of phages as a modern platform for vaccines for human and animal diseases is discussed.