Isolation of native, biochemically purified triosephosphate isomerase from a Chinese strain of Schistosoma japonicum and its protective efficacy in mice

Abstract

The glycolytic enzyme triosephosphate isomerase (TPI) was isolated biochemically from homogenates of a Chinese strain of Schistosoma japonicum (Sjc). Purified SjcTPI migrated on SDS polyacrylamide gels with an apparent molecular size of 28 kDa and had an enzyme activity of 177 IU/mg protein. Immunization of mice with the purified, native SjcTPI resulted in a modest reduction in adult worm burdens relative to adjuvant control mice after the cercarial challenge. No significant reduction in worm burden was noted compared with a soluble extract of adult worm antigen (SWAP). However, mice immunized with SjcTPI exhibited a marked and significant reduction in the number of eggs deposited in the liver relative to both SWAP immunized mice (47-64% reduction) and adjuvant control mice (58-60% reduction). The SjcTPI offers promise as a potential schistosomiasis japonica vaccine antigen, possibly as a 'cocktail' with other Sjc recombinant antigens under investigation. Show more