A novel recombinant protein vaccine for human schistosomiasis caused by Schistosoma mansoni is under development in our laboratories. The Sm-TSP-2 schistosomiasis vaccine is comprised of a 9 kDa recombinant protein corresponding to the extracellular domain of a unique S. mansoni tetraspanin. Sm-TSP-2 was expressed as a recombinant protein secreted by the yeast Pichia Pink, and purified in a two-step process, which resulted in a protein recovery yield of 31 percent and a protein purity of 97 percent The developed processes are suitable for the production of purified protein for subsequent formulation and Phase 1 clinical studies.
Schistosomiasis is a parasitic disease spread by fresh water snails. After malaria, schistosomiasis is the most deadly parasitic disease plaguing more than 250 million people worldwide. Together with hookworm disease and leishmaniasis, it ranks as the neglected tropical disease with the highest disease burden as defined by disability-adjusted life years (DALYs). While the GBD 2010 estimated that the world lost 3.3 million DALYs from schistosomiasis in 2010, other estimates suggest that DALYs lost may even be an order of magnitude higher if chronic morbidities such as malnutrition, inflammation, and pain are also taken into consideration. In addition, there is some evidence it causes severe damage to internal organs, inflicts social stigma on young girls and is an important co-factor in the spread of HIV-AIDS.
Other current activities include testing for long-term stability of the vaccine.