Identification of Apoptotic Cells
Next, we sought to determine which types of cells were affected by apoptosis. Since apoptotic cells were observed around vessels, we labeled sections using markers for vascular endothelial cells, pericytes and astrocytes. CD31-expressing cells were consistent with apoptotic cells bound to vessels (Fig. 4), while cells expressing NG2- or GFAP were not stained. There results indicate that the HPV vaccine induced vascular endothelial cell apoptosis.