Aberrant expression of HLA-DR antigens by insulin-containing beta-cells in recent-onset type I diabetes mellitus.
The pancreases of 14 children who died of type I diabetes were studied immunohistochemically for aberrant expression of HLA-DR antigens on islet endocrine cells. Two cases in which no residual insulin-secreting beta-cells were present had no evidence of HLA-DR expression on endocrine cells. Insulin-containing islets were present in the remainder, and HLA-DR-positive endocrine cells were demonstrable in all of them. Endocrine cells expressing HLA-DR were present in 171 of 630 insulin-containing islets from all the cases. However, HLA-DR-positive endocrine cells were not seen in 2060 insulin-deficient islets, providing evidence that of the four hormone-producing cells in the pancreas only the beta-cells expressed HLA-DR. Sections double stained for HLA-DR and the pancreatic hormones confirmed this view. Most islets in which HLA-DR-positive endocrine cells were seen had no evidence of insulitis, suggesting that within an individual islet, aberrant expression of HLA-DR on beta-cells may precede the inflammatory infiltrate.
D002648:Child; D002675:Child, Preschool; D003922:Diabetes Mellitus, Type 1 / Q000235:genetics* / Q000276:immunology; D005260:Female; D006681:HLA-D Antigens / Q000235:genetics*; D006684:HLA-DR Antigens / Q000235:genetics*; D006801:Humans; D007124:Immunoenzyme Techniques; D007223:Infant; D007328:Insulin / Q000378:metabolism; D007515:Islets of Langerhans / Q000276:immunology*; D008297:Male
D006681:HLA-D Antigens; D006684:HLA-DR Antigens; D007328:Insulin