FIG. 2.
Immunohistochemical detection of poliovirus antigen in infected mice. Poliovirus antigens were detected in PVR-transgenic (A, C, and E) and PVR-transgenic/Ifnar knockout (B, D, and E) mice with a rabbit polyclonal antibody recognizing the poliovirus capsid antigen. The mice were intravenously inoculated with 2 × 107 PFU of poliovirus. (A) Liver of the PVR-transgenic mice on day 1 p.i. Poliovirus antigen-positive cells, indicated by arrows, were focally observed with slight cellular infiltration around the infected cell. (B) Liver of PVR-transgenic/Ifnar knockout mice on day 1 p.i. Hepatic cells positive for poliovirus were observed in a zonal pattern. (C) Spleen of PVR-transgenic mice on day 1 p.i. A few very weakly stained cells are observed in the marginal zone, indicated by arrowheads. (D) Spleen of PVR-transgenic/Ifnar knockout mice on day 1 p.i. Many poliovirus antigen-positive large cells are localized in the marginal zone. The cells were identified as macrophages on the basis of the detection of CD11. (E) Pancreas of PVR-transgenic mice on day 3 p.i. A small cluster of cells positive for poliovirus antigen was observed in the lobulus in association with a slight inflammatory reaction. The poliovirus antigen was observed constantly in all mice. (F) Pancreas of PVR-transgenic/Ifnar knockout mice on day 3 p.i. Numerous acinar cells positive for the poliovirus antigen were distributed in many lobuli of the pancreas. Only a few poliovirus antigen-positive cells were observed in Langerhans' islets in the bottom left. (A) Bar, 125 μm.