Platelet CypD mediates PNA accumulation in brain tissue following cerebral ischemia-reperfusion injury. Male and female CypD^plt−/− mice or littermate controls (CypD^plt+/+) were subjected to 1 hour of cerebral ischemia followed by 23 hours of reperfusion (tMCAO). (A) Representative images of platelet-neutrophil complexes, as costained by GPIb (platelet, green) and myeloperoxidase (neutrophils, red), in ischemic brain tissue 24 hours after stroke. Blue staining shows nuclei (DAPI). The boxed areas in each panel are shown enlarged (insets). (B) Representative dot plots of flow cytometric analysis of PNAs in brain tissue. (C) Quantification of the number of PNAs in the ischemic hemisphere analyzed by flow cytometry 24 hours after stroke.