Authors:
Boris Calderon, Anish Suri, Mark J. Miller, and Emil R. Unanue
Summary:
Islets of Langerhans from normal mice contained dendritic cells (DCs) in the range of 8–10 per islet. DCs were found in several mouse strains, including those from lymphocyte-deficient mice. DCs were absent in islets from colony stimulating factor-1 deficient mice and this absence correlated with small size islets. Most DCs were found next to blood vessels and resided in islets for several days. Some DCs contained insulin-like granules, and most expressed peptide–MHC complexes derived from β cell proteins. Islet DCs were highly effective in presenting β cell antigens to CD4 T cells ex vivo. Presentation of β cell-derived peptide–MHC complexes by DCs neither depended on islet inflammation nor correlated with the extent of spontaneous β cell death. Periislet stroma DCs did not contain β cell peptide–MHC complexes; however, 50% of DCs in pancreatic node were positive. Hence, presentation of high levels of β cell antigens normally takes place by islet DCs, a finding that has to be placed in the perspective of autoimmune diabetes.
Source:
The Proceedings of the National Academy of Sciences of the USA, Vol. 105, No. 16, 6121-6126 (04/22/08)