title: Murine CR1/2 targeted antigenized single-chain antibody fragments induce transient low affinity antibodies and negatively influence an ongoing immune response.
abstract: We have generated a single-chain antibody which recognizes murine CR1/2 and carries a genetically fused influenza hemagglutinin derived peptide. Theoretically such a construct is able to crosslink the B cell antigen receptor and CR1/2 on peptide specific B cells. The construct was able to reach its CR1/2 positive target cells, yet intraperitoneal delivery of the construct elicited an IgM response only slightly exceeding that induced by the free peptide. Providing T cell help by the injection of peptide specific lymphocytes did not alter the response in essence, that is anti-peptide IgG was not detectable even after booster immunizations. When used as a booster vaccine following injection of the peptide in adjuvant, the construct even inhibited the development of IgG1 and IgG3 anti-peptide antibodies. These data indicate that although targeting of antigen to CR1/2 on B cells can enhance transient proliferation or differentiation of antigen specific B cells it cannot induce strong, longlasting humoral immune responses. Furthermore, CR1/2 targeting constructs may negatively influence an ongoing immune reaction.
authors: Research Group of the Hungarian Academy of Sciences at the Department of Immunology, Eötvös Loránd University, Budapest.
authors: József
authors: J
authors: Prechl
authors: Eszter
authors: E
authors: Molnár
authors: Zsuzsanna
authors: Z
authors: Szekeres
authors: Andrea
authors: A
authors: Isaák
authors: Krisztián
authors: K
authors: Papp
authors: Péter
authors: P
authors: Balogh
authors: Anna
authors: A
authors: Erdei
mesh_terms: D000818:Animals; D000906:Antibodies / Q000276:immunology*; D001402:B-Lymphocytes / Q000276:immunology; D006389:Hemagglutinins, Viral / Q000235:genetics / Q000276:immunology; D007128:Immunoglobulin Fragments / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D010455:Peptides / Q000235:genetics / Q000276:immunology; D017463:Receptors, Complement 3b / Q000235:genetics / Q000378:metabolism*; D017464:Receptors, Complement 3d / Q000235:genetics / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism*; D013154:Spleen / Q000166:cytology / Q000378:metabolism; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D000906:Antibodies; D006389:Hemagglutinins, Viral; D007128:Immunoglobulin Fragments; D010455:Peptides; D017463:Receptors, Complement 3b; D017464:Receptors, Complement 3d; D011993:Recombinant Fusion Proteins