IgG Subclass‐Associated Differences in Anti‐Schistosomal Antibody Specificity

Consecutive sera from before and after treatment were collected from 23 patients with a Schistosoma mansoni infection, seven of whom had an early infection. All sera were analysed for IgG1, IgG3 and IgG4 antibody activity against three peptides from the protein Sm 28 GST (24-43, 115-131 and 140-153 aa). In addition, sera from 14 patients, four with an early infection and 10 patients with a chronic infection, were analysed for IgG and IgA antibody activity using seven peptides derived from the protein Sm 28 GST. This molecule has previously demonstrated protective activity against infection in various experimental models. The results are indicative of a subclass-related epitope specificity of the antibodies. Moreover, reactivity to one of the peptides (158-175 aa) was significantly associated with a chronic infectious status.