Immunohistochemical staining of Lewis lung carcinoma tumor sections with anti-CD160 mAb demonstrating CD160⁺ vessels. (A) Vessel network staining in brown was localized at the periphery of the tumor. Blood vessels in the periphery (B) and the center of the tumor (C-D) were also stained with CD160 mAb, whereas tumor cells remained unstained. Original magnification, × 400. (Inset magnification, × 4000)