FIG. 7.

Immunohistology for PVM antigens. Lungs of mice infected with rPVM, ΔNS1, ΔNS2, or ΔNS12 were harvested on day 6 postinfection and were formalin fixed. Paraffin sections were stained with hematoxylin-eosin and antibody specific to PVM. Representative sections are shown for each virus. Note the abundant viral antigen (brown color) in NS1 and rPVM lungs and much less viral antigen in the lungs of NS2- and NS12-infected mice (hematoxylin counterstain; magnification, ×100).