A contrast agent recognizing activated platelets reveals murine cerebral malaria pathology undetectable by conventional MRI
J. Clin. Invest. Constantin von zur Muhlen, et al. 118:1198 doi:10.1172/JCI33314 [Go to this article.]

Figure 7
Platelet and leukocyte accumulation in the brain following the intrastriatal injection of TNF. (A) Top: Platelets localized within blood vessel in the brain close to the injection site (brown, DAB), visualized by cresyl-violet counterstain. Bottom: Confocal triple-labeling immunocytochemistry identified platelets (red) and ED-1–positive cells (green) inside a vessel with an intact endothelium, as revealed by GLUT1 (blue) staining. (B) Number of GPIIb/IIIa-positive elements in the injected hemisphere following microinjection into the striatum of 1 μg TNF (diamonds), 1 ng IL-1 (triangles), or saline (squares) in a volume of 1 μl for rats or 0.5 μl for mice. (C–E) Total brain leukocytes, as identified by leukocyte common antigen (LCA; C), ED-1–positive recruited monocytes and activated microglial cells present in the brain parenchyma (D), and ED-1–positive recruited monocytes associated with the luminal portion of the brain vasculature (E), detected by immunohistochemistry over 24 h following intrastriatal injection of TNF (squares) or saline vehicle (diamonds). (F–H) Representative photographs showing the absence of leukocytes in the meninges (F) or parenchyma (G) and their presence in the parenchyma following injection of TNF (H) after immunohistochemical labeling for leukocyte common antigen. (I–L) Double-labeling immunocytochemistry (I and K) and confocal imaging (J and L) of ED-1–positive cells and the brain vasculature (as identified by GLUT-1) highlight the differences in mononuclear cell recruitment patterns in the parenchyma (I and J) and meninges (K and L). Note in the meninges the presence of large numbers of ED-1–positive cells (blue, VIP; red, FITC) that appear to have free passage from the vasculature (brown, DAB; blue, AF-636) compared with the same cells in the parenchyma that appear vessel associated. (K, inset) High-power view of extravascular ED-1–positive cells. ELISA results are expressed as pg MCP-1/mg total protein ± SEM. Cell numbers in brain are expressed per mm² ± SEM. *P < 0.05 versus vehicle control. Scale bars: 20 μm (A and F–J); 40 μm (K and L); 10 μm (K, inset).