Induction of a protective immune IgE response in rats by injection of defined antigens of schistosomulum-released products: immunochemical properties of the target antigens.
Brown Norway rats were injected without adjuvant with the soluble products liberated in a 16-hour culture by schistosomula (schistosomula-released products, SRP-A). A strong cytotoxic and protective IgE response was elicited, mainly directed against 22- and 26-kilodalton (kDa) SRP-A molecules. In the present study, we have attempted to characterize further those molecules. Metaperiodate denaturing treatment of the SRP-A glycans before injection into rats did not modify the immunogenicity of the SRP-A antigens. Results obtained by lectin affinity suggested that the 22- and 26-kDa molecules were glycoconjugates binding to ConA. Preparative sodium dodecylsulfate electrophoresis has allowed the separation of enriched fractions of 22- and 26-kDa molecules which have been injected separately into rats. The corresponding sera were tested in antibody-dependent cell cytotoxicity and displayed a significant cytotoxic IgE response (65 and 53%, respectively) towards the larvae. These results lend further support to the view that the 22- and 26-kDa antigens are the major targets of the protective IgE response and thus appear as potentially protective antigens.
D000818:Animals; D000920:Antibody-Dependent Cell Cytotoxicity; D000947:Antigens, Helminth / Q000032:analysis / Q000276:immunology*; D001792:Blood Platelets / Q000276:immunology; D004591:Electrophoresis, Polyacrylamide Gel; D006023:Glycoproteins / Q000032:analysis; D007073:Immunoglobulin E / Q000032:analysis* / Q000276:immunology; D008264:Macrophages / Q000276:immunology; D010084:Oxidation-Reduction; D010504:Periodic Acid / Q000494:pharmacology; D051381:Rats; D011914:Rats, Inbred BN; D012547:Schistosoma / Q000276:immunology*; D012552:Schistosomiasis / Q000276:immunology
D000947:Antigens, Helminth; D006023:Glycoproteins; D010504:Periodic Acid; D007073:Immunoglobulin E; C009288:metaperiodate