Electron Microscopy of Early Cytoplasmic Changes Due to Influenza Virus

Abstract

Recently improved methods for visualization of thin tissue sections by electron microscopy have been applied to the study of early changes in the bronchial epithelium of mice infected by inhalation of aerosols of influenza virus. In confirmation of previous findings by the authors, inclusion bodies have been demonstrated in ciliated and non-ciliated cells of infected bronchial epithelium. In addition to 3 strains of mouse-adapted Type A virus, 2 unadapted strains gave qualitatively the same results. The inclusion bodies were found to be composed largely of particles of a size estimated to correspond to the known size of influenza virus. The viral lesion of the cytoplasm was also associated with linear formations which were thought to be abnormal forms of endoplasmic reticulum. Well developed microvilli were found on the ciliated borders of ciliated cells, but no evidence was found of viral growth in this region.

Electron Microscopy of Monkey Kidney Cell Cultures Infected with Rubella Virus

“…It is reasonable to assume that the lamellar structures are induced by infection with rubella virus, since they are not present in uninfected cell cultures. Although the appearance of a variety of membranous structures in tissue culture cells as a result of virus infection has been reported (1, 4, 5,10,12), the appearance of annulate lamellae is unusual. The laminated structures observed in tissue culture cells infected with herpes virus (18), adenoviruses (10,19), and other viruses (1,4,12) do not appear to be of the type reported here.…”

“…Although the appearance of a variety of membranous structures in tissue culture cells as a result of virus infection has been reported (1, 4, 5,10,12), the appearance of annulate lamellae is unusual. The laminated structures observed in tissue culture cells infected with herpes virus (18), adenoviruses (10,19), and other viruses (1,4,12) do not appear to be of the type reported here. The possible exception is the complex laminated structure observed by Lapis (14), in the cytoplasm of KB cells infected with adenovirus 12. It is interesting to note that annulate lamellae have been described for a variety of cells (3, 7, 8, 11,26) and, in particular, are quite frequent in invertebrate eggs (24,27).…”

Electron Microscopy of Hela Cells Infected With Adenoviruses

“…of the electron microscope were essentially the same as used in previous work (23). The fixative in most of the experiments consisted of 1 per cent osmium tetroxide buffered to pH 7.4-7.5 (Palade (24)).…”

Electron microscopic observations of influenzal pneumonitis.

“…Bronchial epithelial cells became necrotic leaving only the basal layer intact. These changes are well advanced by the third day (Spencer, 1972 Possible granular osmiophilic bodies, which were described as a microscopy of virus particles by Harford, Hemlin and Parker (1955), appeared in the cytoplasm of bronchial epithelial cells on the 2nd and 3rd days in this experiment.…”