Diabetogenic CTL arrest in postcapillary pancreatic venules.
(A and B) Pancreas sections from prediabetic RIP-LCMV.GP animals (n = 6) stained for CD8 and CD4. Autofluorescence shows general morphology. Red arrows indicate vascular structures with maximum diameter (μm). (C and D; corresponds to Supplemental Video 1) Vascular staining in naive animals. w/h = 1.52/d = 5/z = 32. (E) MIP image corresponds to Supplemental Video 2. w/h = 0.56/d = 4/z = 25. CTL can be seen in virtual arrest within postcapillary venules (red arrows). Inset represents a single Z-plane. (F) Cellular tracking shows immotile cells in the vascular bed (red arrows), lacking the “dragontails” that signify motility. (G) MIP image corresponds to Supplemental Video 3. w/h = 1.52/d = 5/z = 21. Setup analogous to E in another prediabetic animal. Green arrows indicate arrested cells in contact with the vascular wall. Cyan arrows show cells “crawling” against the vascular wall. White arrow shows endogenous “ghost” cells in arrest against the endothelium. Yellow arrow shows freely flowing transferred cell. Red arrow shows leakage of the vascular dye. (H) MIP image corresponds to Supplemental Video 4. w/h = 1.52/d = 5/z = 26. Setup analogous to E and G in another prediabetic animal. Green arrows point toward arrested transferred cells. (I) Image of the same region shown in H 8 minutes after dye injection demonstrates vascular leakage of the dextran–Texas Red dye (red arrows). Scale bars: 100 μm (A–E, G–I); 50 μm (F, insets in E, G).