FIG. 5.
Experimental induction of OPC by JSRVJS7. Lung tissue from a JSRVJS7-inoculated lamb was fixed in neutral formalin, sectioned at 4 to 6 μm, and stained. (A) Microscopic tumor nodule detected in lamb number 1615 (hematoxylin and eosin stain; bar = 40 μm). Note the increased numbers of alveolar macrophages in alveoli surrounding the tumor nodule (arrows). (B) JSRV antigen presence in the same tumor nodule detected by immunohistochemistry using rabbit antiserum to JSRV capsid developed using Vector Red and using Carazzi's hematoxylin as a counterstain (bar = 40 μm).