Effect of syngeneic islet antigen administration on complement-dependent antibody-mediated cytotoxicity to islet cells and diabetes onset in diabetes-prone BB/OK rats.
Diabetes-prone BB/OK rats aged 30 to 35 days were subjected to three sequential intrasplenic injections of unfractionated homogenate prepared from Langerhans' islets of newborn syngeneic BB/OK rats. Syngeneic islet antigen administration resulted in increased complement-dependent antibody-mediated cytotoxicity (C'AMC) to rat pancreatic islet cells in serum, compared to buffer-treated control animals as detected by 51Cr-release assay. However, the increase of anti-islet-cell cytotoxicity neither impaired glucose tolerance nor affected the incidence of diabetes and the age at manifestation. In contrast to BB/OK rats developing diabetes, animals remaining long-term normoglycaemic did not show an enhancement of cytotoxicity to islet cells within twelve days after the first islet antigen injection as revealed retrospectively. In conclusion, humoral mediated anti-islet-cell cytotoxicity is not decisively involved in pancreatic beta-cell destruction and promotion of diabetes development in BB/OK rats, but animals becoming diabetic seem to be characterized by a stronger immunological reactivity upon syngeneic islet antigen challenge as indicated by an increase of anti-islet C'AMC compared to long-term normoglycaemic rats.
Schröder
D
D
Institute of Diabetes Gerhardt Katsch, Karlsburg of the Ernst-Moritz-Arndt-University of Greifswald, Germany.
Schmidt
S
S
Klöting
I
I
Hehmke
B
B
D000818:Animals; D000920:Antibody-Dependent Cell Cytotoxicity; D000941:Antigens / Q000276:immunology*; D003165:Complement System Proteins / Q000276:immunology*; D003922:Diabetes Mellitus, Type 1 / Q000276:immunology*; D007330:Insulin Antibodies / Q000032:analysis; D007515:Islets of Langerhans / Q000276:immunology*; D051381:Rats; D011913:Rats, Inbred BB
D000941:Antigens; D007330:Insulin Antibodies; D003165:Complement System Proteins