Different lymphocyte subset distribution within "insulitis" islets of normoglycaemic and prediabetic BB/OK rats of similar age.
The fact that insulitis occurs also in normoglycaemic BB rats led us to investigate the phenotypes of lymphocytes invading the pancreatic islets of prediabetic BB/OK rats in comparison to age- and sex-matched normoglycaemic animals in a retrospective analysis. By using a panel of monoclonal antibodies we investigated the number of pan T-cells, T-helper cells, cytotoxic T-cells and NK-cells and determined the number of activated cells by measurement of class I, class II and IL-2 receptor positive cells. The bound primary antibodies were visualized using the APAAP-technique. The prediabetic rats showed a significantly decreased pancreatic insulin content which was drastically reduced at diagnosis of diabetes. This was accompanied by reduction of the B-cell volume density. The prediabetic as well as the long-term normoglycaemic BB rats showed an accumulation of mononuclear cells (all phenotypes investigated) within the pancreatic islets. Concerning the phenotypes of infiltrating cells there was no qualitative difference between long-term normoglycaemic and prediabetic rats but quantitatively an enhanced amount of W3/25+, OX-8+, OX-6+ and ART-18+ cells could be observed in the prediabetic animals. From our results we conclude that an immunological B-cell destructive process occurs also in long-term normoglycaemic BB rats by participation of mononuclear cells qualitatively not different from those observed in prediabetic animals. Activated T-cells (OX-19+, OX-8+, W3/25+) expressing class II antigens (OX-6+) and the IL-2 receptor (ART-18+) seem to play a significant role in the amplified immunological pancreatic B-cell destruction.
Central Institute of Diabetes, Gerhardt Katsch, Karlsburg/GDR.
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S
Lucke
T
T
Diamantstein
H J
HJ
Hahn
D000818:Animals; D001786:Blood Glucose; D003921:Diabetes Mellitus, Experimental / Q000175:diagnosis; D005260:Female; D007328:Insulin / Q000378:metabolism; D008214:Lymphocytes / Q000166:cytology*; D008297:Male; D010194:Pancreatin / Q000276:immunology*; D011236:Prediabetic State / Q000276:immunology* / Q000378:metabolism; D051381:Rats; D011913:Rats, Inbred BB / Q000235:genetics*; D011919:Rats, Inbred Strains / Q000235:genetics*; D012189:Retrospective Studies
D001786:Blood Glucose; D007328:Insulin; D010194:Pancreatin