Autoantibodies against pancreatic beta-cells: characterization by western blot analysis in the non-obese diabetic (NOD) mouse.
The NOD mouse is a relevant model for studying autoimmune diabetes. As in human insulin-dependent diabetes mellitus, the nature of the autoantigen towards which the immune system is directed remains to be clarified. It has been shown that T cells are central to the disease process. However, autoantibodies may be used as a probe to identify islet autoantigens to which self tolerance is defective. Using Western blot analysis, we characterized autoantibodies which are specific for a 58 kDa islet antigen and a 29 kDa antigen. The 58 kDa autoantigen was present in cellular extracts prepared from rat tumoral insulin-secreting cells (Rin5F) and NOD islets but not from most other non-insulin-secreting cell lines. By contrast the 29 kDa antigen was a ubiquitous antigen expressed in all cell lines tested and was not further characterized since it is very likely to be responsible for secondary immunization rather than play any role in the NOD disease process. Anti-58 kDa autoantibodies were detected in all diabetic male and female NOD animals as well as in sera from old non-diabetic NOD animals. Anti-58 kDa antibodies were not detected in sera from young NOD mice (less than 6 weeks of age) or in sera from other conventional laboratory strains of mice including autoimmune prone animals such as MRL/lpr and (NZB x NZW)F1 mice. A monoclonal antibody (72.2) specific for the 58 kDa structure was obtained, which allowed further characterization of the corresponding islet cell antigen. The expression of the 58 kDa antigen was evidenced by Western blot analysis in normal islets and in a mouse neuroblastoma cell line.
Villà
M C
MC
INSERM U25, Hôpital Necker, Paris, France.
Bécourt
C
C
Gia
H P
HP
Sempé
P
P
Portier
M M
MM
Bach
J F
JF
Boitard
C
C
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D001323:Autoantibodies / Q000032:analysis*; D001324:Autoantigens / Q000276:immunology; D015153:Blotting, Western; D002460:Cell Line; D003922:Diabetes Mellitus, Type 1 / Q000276:immunology* / Q000473:pathology; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D005455:Fluorescent Antibody Technique; D007515:Islets of Langerhans / Q000276:immunology* / Q000473:pathology; D008297:Male; D051379:Mice; D016688:Mice, Inbred NOD; D008819:Mice, Nude; D008970:Molecular Weight; D014407:Tumor Cells, Cultured
D000911:Antibodies, Monoclonal; D001323:Autoantibodies; D001324:Autoantigens