356730.fig.004a
(a)
356730.fig.004b
(b)
356730.fig.004c
(c)
356730.fig.004d
(d)
Figure 4: Immunohistochemical staining of neutrophils (stained with a rat anti-mouse IgG) and macrophages (stained with anti-MAC-2 IgG) in lung tissue excised from a control and a K. pneumonia-infected mouse (42 hr after challenge). Immunostained cells appear dark brown. Control lungs revealed no neutrophils (a) or macrophages (b), only normal alveolar wall structure. Infected lungs had significant neutrophil accumulation (c), with very little macrophage infiltration (d, indicated by arrowheads). Images were taken with a magnification of 400x, black bar indicates 100 μm.