NK cells are not required for the progression to diabetes.

<p>A) The left panel shows the rate of spontaneous diabetes in NOD.NK1.1 littermates that received either anti-NK1.1 or an isotype-matched control IgG from 3 through 10 weeks of age (10 litters). In the middle panel, purified CD4⁺ T cells from diabetic NOD mice were transferred into <i>Rag2^−/−</i> NOD.NK1.1 mice and treated with anti-NK1.1 or an isotype-matched control IgG. Both groups in the adoptive transfer experiments also received anti-CD8 to ensure exclusively CD4⁺ T cell-mediated disease. The far right panel shows the incidence of disease in unmanipulated NOD mice and NOD.NK1.1 mice in our colony. P values were calculated using the Mann-Whitney U test. B) Five hundred micrograms of BrdU was in injected intravenously and mice were sacrificed one hour later. Flow cytometric plots of cells isolated from the pancreas from one representative experiment are shown. Graphs are cumulative of 3 independent experiments involving littermates. C) NOD.NK1.1 mice were sacrificed after 10 weeks after receiving noted treatment regimens. Isolated leukocytes from the pancreatic lymph node or pancreas with stimulation with PMA and ionomycin for 3 hours in the presence of GolgiStop and assayed for intracellular IFNγ or IL-17 production by CD4⁺ T cells or CD8⁺ T cells, as indicated. Graphs are cumulative of 3 independent experiments involving littermates. No significant difference between groups was demonstrated in any parameter assayed.