title: Modulation of the immune response to ragweed allergens by peptic fragments.
abstract: Fragments of short ragweed extract were prepared by peptic digestion and fractionated by molecular exclusion chromatography. We focused on fragmenting a ragweed fraction that was enriched for Amb aI. Digestion products in the molecular weight range of 5-15 kD (fSRW) were examined for their antigenic, immunogenic and immunosuppressive properties. fSRW was poorly immunogenic and unable to induce ragweed-specific PCA reactions in rat skin or to bind to anti-ragweed IgG antibodies. Intravenous administration of fSRW either prior to or after intraperitoneal immunization with a ragweed preparation resulted in a significant suppression of the immune response. T cells isolated from lymph nodes of mice immunized with ragweed were stimulated by fSRW in a lymphoproliferation assay. Moreover, T cells from mice injected with fSRW were immunosuppressive when transferred into mice immunized with intact ragweed antigens. Our data demonstrate that peptic fragments (fSRW) of ragweed lack B-cell determinants while retaining their T-cell immunoregulatory properties. Potentially these peptides are less likely to cause adverse reactions in allergen sensitive patients and thus offer a new approach to allergen immunotherapy.
authors.affiliation: Department of Molecular Genetics, Biochemistry and Microbiology, University of Cincinnati Medical Center, Ohio 45267-0524.
authors.forename: J G
authors.initials: JG
authors.lastname: Michael
authors.forename: A
authors.initials: A
authors.lastname: Litwin
authors.forename: V
authors.initials: V
authors.lastname: Hassert
authors.forename: A
authors.initials: A
authors.lastname: Pesce
mesh_terms: D000818:Animals; D003888:Desensitization, Immunologic; D005260:Female; D007114:Immunization; D007073:Immunoglobulin E / Q000096:biosynthesis; D007165:Immunosuppression Therapy; D008213:Lymphocyte Activation; D051379:Mice; D008970:Molecular Weight; D010446:Peptide Fragments / Q000008:administration & dosage / Q000276:immunology* / Q000302:isolation & purification; D011058:Pollen / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D010446:Peptide Fragments; D007073:Immunoglobulin E