FIG 9.

Histopathological analysis of tissues collected from NHPs after WT CO92 aerosol challenge. Lungs, pleurae, mediastinal lymph nodes, liver, and spleen tissues were collected from the control (3 or 4 days after WT CO92 challenge) and immunized (82 days after WT CO92 challenge) NHPs after euthanization and processed for histopathological analysis. The inset from lungs revealed the presence of coccobacilli, presumptively Y. pestis, by Gram staining. The magnifications of the images are indicated.