Immunocytochemical localization of factor VIII-related antigen in tumors of the human central nervous system.
Using both immunohisto- and immunocytochemical techniques with periodate-lysine-paraformaldehyde (PLP) fixation, we have studied the distribution of Factor VIII-related antigen (FVIIIR:Ag) in 12 cases of tumors of the human central nervous system (CNS) and one sample of non-tumor brain tissue. FVIIIR:Ag was found both extracellularly and intracellularly. It was localized in the vascular lumen, between endothelial cells, and in the endothelial cell basement membrane. In the endothelial cell cytoplasm, FVIIIR:Ag was found in the endoplasmic reticulum, perinuclear space, and in intracytoplasmic vacuoles and vesicles. Characteristic of malignant tumors (six out of seven) was a strongly-positive dilated endoplasmic reticulum. This may reflect increased FVIIIR:Ag synthesis in the endothelial cells of malignant tumors. Only one of five benign tumors showed such staining. Six of 12 tumors and the non-tumor brain showed perinuclear FVIIIR:Ag. Both ad- and abluminal vesicles in the tumor endothelial cells contained FVIIIR:Ag suggesting that endocytosis, transcellular transport, and/or endocytosis, as well as FVIIIR:Ag synthesis occurs. The non-tumor brain showed normal capillary structure and very little FVIIIR:Ag immunoreactivity. The relationship of these FVIIIR:Ag abnormalities to the hypercoagulable state seen in some malignant brain tumor patients remains to be clarified.
D000941:Antigens; D001932:Brain Neoplasms / Q000098:blood supply / Q000276:immunology* / Q000648:ultrastructure; D004727:Endothelium / Q000276:immunology; D005169:Factor VIII / Q000276:immunology*; D006651:Histocytochemistry; D006801:Humans; D007120:Immunochemistry; D008577:Meningeal Neoplasms / Q000098:blood supply / Q000276:immunology* / Q000648:ultrastructure; D008854:Microscopy, Electron; D014841:von Willebrand Factor
D000941:Antigens; D014841:von Willebrand Factor; D005169:Factor VIII