SDF-1 expression in endothelial cells lining capillary vessels revealed by immunohistochemical staining.

(A) Umbilical vein: the endothelium lining the vein stains positive for SDF-1. (B) Placenta: capillaries and blood vessels within chorionic villi are positive for SDF-1. (C) Lymph node: SDF-1 staining marks high endothelial venules within T-cell areas. Isolated cells identified morphologically as macrophages–dendritic cells are positive for SDF-1. (D) Lymph node: endothelium and scattered macrophages within Burkitt lymphoma stain positive for SDF-1. (E) Lung: a medium-size occluded vessel (within an area of organizing pneumonia) with evidence of recanalization displays SDF-1–positive endothelium lining the newly formed intraluminal vessels. (F) Skin: the typical lobular capillary network of a pyogenic granuloma (lobular capillary hemangioma) and small capillaries lined by prominent endothelial cells are positive for SDF-1. Original magnification, ×40.