Figure 4.

Fluorescence microscopy and immunohistology of 9L-GFP-34-1 tumor sections (8 µm). Tumors were implanted in the brain of Fischer rats stereotactically as described in Materials and Methods. (A) Double-channel fluorescent microscopy of brain tissue isolated from rats that received injection of Hoechst dye immediately before euthanasia. Green—GFP; Blue—Hoechst. (B) Anti-CD31 immunohistology of a parallel section. Blood vessels are delineated using secondary antibody-peroxidase/DAB stain with subsequent counter staining with hematoxylin. Magnification 100x.