FIGURE 2

Tenascin (TN) (light brown) and CD68-positive macrophages/microglia (dark red) in gliomas (double immunohistochemistry: anti-TN/3,3′-diaminobenzidine + CD68/3-amino-9-ethylcarbazole). A, TN-positive area (vascular and interstitial TN expression) in a glioblastoma is heavily infiltrated by CD68-positive macrophages, 100 ×. B, a higher number of macrophages are present in the TN-positive area (left and middle) compared with TN-negative area (at right), where only occasional macrophages are present, 100 ×. C, TN-negative area in a glioblastoma. Most of the CD68-positive cells are microglia (arrowheads). A small cluster of macrophages (empty arrow) are seen in the lower part of the figure, 200 ×. D, glioblastoma. Streaming of macrophages via weak TN-positive extracellular matrix (arrowheads) toward necrosis (N). Edge of the necrotic area is showing homogenization of TN; a ribbon of newly forming stromal vessels (V) is seen at the edge of necrosis; no CD68-positive cells are present in this area, 100 ×. E, higher magnification (400 ×) from framed area from D. F, glioblastoma. Macrophages are adhering to TN-positive basement membrane zone (light brown) of newly forming stromal vessel tube (arrowheads), whereas in the opposite side, basement membrane zone is lacking TN (empty arrows) and there are no macrophages, 400 ×.