Human IgG1 and IgG3 recognition of Schistosoma mansoni 14 kDa fatty acid-binding recombinant protein

The Schistosoma mansoni gene coding for a 14-kDa fatty acid-binding protein was amplified by PCR and subcloned into the prokaryotic expression vector pMAL-c2. Escherichia coli DH5 alpha was transformed with the pMAL-Sm14 cons truct, and gene expression was induced by isopropyl-beta-D-thiogalactopyran oside. The resulting recombinant (r) fusion protein was purified by affinit y chromatography and confirmed by immunoblot analysis using antimaltose-bin ding protein or anti-Sm14 antibodies. Additionally an antibody isotype prof ile was determined in sera of schistosomiasis patients to rSm14 or soluble adult worm antigen preparation. IgG1 and IgG3 subclass antibodies to rSm14 were predominant in sera of all patients studied whereas low levels of IgM, IgA or IgE were measured Expression of a S. mansoni gene encoding a vaccin e candidate is an important step to better study human immune responses to defined antigens.