Modulation of CD8⁺ T cell populations.

<p>(A) Upper panels: representative images of infiltrated islets stained for CD4 (red), CD8 (green) and DNA (blue) on pancreatic sections from mice treated with either vehicle or 100 U/kg/day of DM199 for 18 weeks. Lower panels: representative images of islets immuno-stained for insulin (brown) and counterstained with H&E. (B) CD4⁺/CD8⁺ ratios in islets. Pancreatic sections from all treatment groups at the indicated time points were fluorescently stained for CD4 and CD8; positive cells were manually counted in a blinded fashion (15 islets/mouse; n = 3–10 mice/group). Data are presented as the mean +/− SEM of the CD4⁺/CD8⁺ ratios for each treatment group. (C) DM199 treatment reduces activated CD8⁺ T cells (CTLs) in pancreatic lymph nodes (PLN). Single cell suspensions of PLN from treated mice were stained against CD3, CD8 and CD44, analyzed by FACS and the percentages of CD44⁺CD8⁺ cells within the CD3⁺ T cell population were calculated. Data are mean ± SEM (n = 4–10 mice/group). *<i>P</i><0.05 <i>vs.</i> control, ***<i>P</i><0.001 <i>vs.</i> control, using a one-way ANOVA with Tukey post-hoc multiple comparisons test.