title: Insulin as a target antigen in autoimmune diabetes: a natural repertoire as the source of antibody response.
abstract: A solid-phase immunoenzymatic technique with B1- or B29-biotinylated insulin coupled to avidin-coated wells was used to characterize serum anti-insulin antibodies and to locate insulin antibody-producing B lymphocytes in different organs of mice. Low natural serum anti-insulin IgM and IgG antibodies were found in ten different healthy inbred strains of mice. Prediabetic non-obese diabetic (NOD) mice had significantly higher measurements than BALB/c mice (P < 0.05). Anti-insulin IgM antibody-producing B lymphocytes were found in bone marrow and spleen of NOD mice and healthy strains of mice, but not in peripheral lymph nodes, thymus, blood or pancreas. B29-fixed insulin was more frequently recognized than B1-fixed insulin. There was no relationship to the MHC or to other immune markers. IgG insulin antibody-producing cells were not detected. IgG insulin antibody-producing cells appeared in the draining lymph node and in the blood 10 days after immunization with insulin. IgM insulin-recognizing cells in the spleen were reduced in number during the same period (P < 0.05-0.01 for BALB/c, DBA2, B10.D2 and NOD), suggesting migration of these cells. This was tested by in vivo staining of spleens with the red-fluorescent membrane linker PKH-26 on day 7 after immunization. Cells from immunized lymph nodes were FACS-sorted on day 10. Insulin antibody-producing B lymphocytes with red-fluorescence were found, indicating a splenic origin. Examination of IgG subclasses showed preferential production of complement-fixing IgG2b in sera and lymph node cells of immunized NOD mice (P < 0.05 vs BALB/c).(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Endocrinology, University Hospital of Internal Medicine, Freiburg, Germany.
authors.forename: K G
authors.initials: KG
authors.lastname: Petersen
authors.forename: A N
authors.initials: AN
authors.lastname: Khalaf
authors.forename: V
authors.initials: V
authors.lastname: Naithani
authors.forename: M
authors.initials: M
authors.lastname: Fabry
authors.forename: H
authors.initials: H
authors.lastname: Gattner
mesh_terms: D000818:Animals; D000917:Antibody Formation; D000941:Antigens / Q000276:immunology*; D001327:Autoimmune Diseases / Q000276:immunology*; D001853:Bone Marrow / Q000276:immunology; D003922:Diabetes Mellitus, Type 1 / Q000235:genetics / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D007074:Immunoglobulin G / Q000097:blood*; D007075:Immunoglobulin M / Q000097:blood*; D007328:Insulin / Q000276:immunology*; D008198:Lymph Nodes / Q000276:immunology; D008214:Lymphocytes / Q000276:immunology*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D016688:Mice, Inbred NOD; D008815:Mice, Inbred Strains; D010179:Pancreas / Q000276:immunology; D013045:Species Specificity; D013154:Spleen / Q000276:immunology; D013950:Thymus Gland / Q000276:immunology
chemical_list: D000941:Antigens; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D007328:Insulin