A mucosally administered recombinant fusion protein vaccine against schistosomiasis protecting against immunopathology and infection

We have constructed and efficiently produced and purified a candidate vaccine against schistosomiasis consisting of a novel hybrid protein in which two dominant T- and B-cell epitopes from Schistosoma mansoni 28 kDa glutathione-S-transferase (Sm28GST) antigen (a.a 24-43 and 191-212) are fused to cholera toxin B subunit (CTB). Intranasal treatment of S. mansoni-infected mice with the hybrid protein, which similar to native CTB was assembled into receptor binding pentamers, significantly reduced total worm burden and liver egg counts due to the induction of Sm28GST-specific antibodies. Immunopathologic granuloma formation in the liver was also significantly suppressed and there was an almost complete suppression of delayed-type hypersensitivity reactions to both Sm28GST and to total soluble egg antigen in infected animals. The results suggest that this type of hybrid protein could be used as a combined anti-immunopathology and anti-infection vaccine against schistosomiasis. (C) 2002 Elsevier Science Ltd. All rights reserved.