Beta cell destruction of pancreatic islets transplanted into diabetic BB/OK rats may be reflected by increased antibody-mediated anti-islet cytotoxicity.
Neonatal rat pancreatic islets can be affected in vitro by ADCC mediated by serum and mononuclear cells from diabetic BB/OK rats or complement-dependent antibody-mediated cytotoxicity (C'AMC) of BB rat serum as revealed by enhanced 51Cr-release. Using a syngeneic islet transplantation system in BB/OK rats this study addressed the question whether the destruction of islets of Langerhans in vivo is reflected by the appearance of ADCC or C'AMC in vitro. The frequency of the appearance of enhanced anti-islet ADCC in newly diagnosed diabetic BB/OK rats amounted to 33% whereas ADCC was not detectable in long-term diabetic rats with a diabetes duration in a range between 50 and 90 days. After transplantation of syngeneic islets beneath the kidney capsule of long-term diabetic BB/OK rats held without immunosuppression the destruction of the islet graft and the persistence of hyperglycaemia was accompanied by an increase of anti-islet ADCC in 66.6% of the animals. While only 18.7% of the long-term diabetic BB/OK rats showed C'AMC against islet cells before transplantation this frequency raised after transplantation and 62.8% of the animals exhibited increased C'AMC within a period of 21 days but with a pronounced individual variability of the time-course. Increased anti-islet cytotoxicity (ADCC or C'AMC) parallels newly initiated or reactivated beta-cell destruction after transplantation and thus seems to reflect this process.
Schröder
D
D
Department of Experimental Diabetes Research, Central Institute of Diabetes, Gerhardt Katsch, Karlsburg, German Democratic Republic.
Wanka
H
H
Hehmke
B
B
Klöting
I
I
Köhler
E
E
Knospe
S
S
Schmidt
S
S
D000818:Animals; D000831:Animals, Newborn; D000920:Antibody-Dependent Cell Cytotoxicity; D003921:Diabetes Mellitus, Experimental / Q000276:immunology* / Q000601:surgery*; D016381:Islets of Langerhans Transplantation / Q000276:immunology / Q000473:pathology*; D051381:Rats; D011913:Rats, Inbred BB; D011917:Rats, Inbred Lew; D013997:Time Factors; D014185:Transplantation, Isogeneic