FIG. 11.

Morphological analysis of lung tissues by transmission electron microscopy. Studies were conducted in infected immunocompetent (A and B) and leukopenic (D and E) mice on day 3 postinfection. Normal ultrastructure of endothelia and epithelia was observed in noninfected immunocompetent (C) and leukopenic (F) mice. Abbreviations: A, alveolar space; B, bacteria; BL, basal lamina; E, edema; En, endothelia; Ep, epithelia; F, fibrosis; N, necrotized tissue; P, polymorphonuclear cell; S, surfactant; V, blood vessel. Scale bar = 1 μm.