Abstract
Rods and spheres believed to represent viral particles were observed at the free surface of entodermal cells of the chorioallantoic membrane 6 to 44 hours after infection. Although occasional short rods revealed poorly defined internal bodies, the majority, as well as all the longer rods (filaments), exhibited no visible internal structure. The spheres presumed to lie central to the plane of section contained an inner body 20 to 22 mµ in diameter. Both forms possessed a dense, sharply defined limiting membrane 30 A thick and a diffuse external coat of lesser density. Where superimposition within the section was minimal, the viral particles were separated by a relatively constant distance. Measured to include this spacing, on the assumption that it reflected the presence of a component of the outer coat, the diameters of a majority of the rods were 50 to 60 mµ, whereas the spheres averaged 60 to 70 mµ. The rods appeared to form by a process of extrusion from the cell wall and became detached either singly or in bundles of variable length. The spheres seemed to differentiate at the cell surface and to acquire the inner body, limiting membrane, and outer coat as they migrated through the membrane of the host cell. No characteristic changes were seen in the nuclei or adjacent cytoplasm, and recognizable viral particles were never encountered in these areas of the cell. No support was obtained for the assumption that the spheres developed primarily by segmentation of the rods. It is suggested that the spherical form of the virus is the elemental infectious unit and that the filamentous form is largely or completely non-infective.
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Selected References
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- ARCHETTI I. Appearances associated with filamentous forms of influenza viruses. Arch Gesamte Virusforsch. 1955;6(1):29–35. doi: 10.1007/BF01242050. [DOI] [PubMed] [Google Scholar]
- BANG F. B. Morphology of viruses. Annu Rev Microbiol. 1955;9:21–44. doi: 10.1146/annurev.mi.09.100155.000321. [DOI] [PubMed] [Google Scholar]
- BURNET F. M. Filamentous forms of influenza virus. Nature. 1956 Jan 21;177(4499):130–130. doi: 10.1038/177130a0. [DOI] [PubMed] [Google Scholar]
- CHU C. M., DAWSON I. M., ELFORD W. J. Filamentous forms associated with newly isolated influenza virus. Lancet. 1949 Apr 9;1(6554):602–602. doi: 10.1016/s0140-6736(49)91699-2. [DOI] [PubMed] [Google Scholar]
- DONALD H. B., ISAACS A. Some properties of influenza virus filaments shown by electron microscopic particle counts. J Gen Microbiol. 1954 Oct;11(2):325–331. doi: 10.1099/00221287-11-2-325. [DOI] [PubMed] [Google Scholar]
- EDDY B. E., WYCKOFF R. W. G. Influenza virus in sectioned tissues. Proc Soc Exp Biol Med. 1950 Oct;75(1):290–293. doi: 10.3181/00379727-75-18174. [DOI] [PubMed] [Google Scholar]
- Francis T., Stuart-Harris C. H. STUDIES ON THE NASAL HISTOLOGY OF EPIDEMIC INFLUENZA VIRUS INFECTION IN THE FERRET : I. THE DEVELOPMENT AND REPAIR OF THE NASAL LESION. J Exp Med. 1938 Oct 31;68(6):789–802. doi: 10.1084/jem.68.6.789. [DOI] [PMC free article] [PubMed] [Google Scholar]
- HARFORD C. G., HAMLIN A., PARKER E. Electron microscopy of early cytoplasmic changes due to influenza virus. J Exp Med. 1955 Jun 1;101(6):577–590. doi: 10.1084/jem.101.6.577. [DOI] [PMC free article] [PubMed] [Google Scholar]
- MORGAN C., ELLISON S. A., ROSE H. M., MOORE D. H. Structure and development of viruses as observed in the electron microscope. I. Herpes simplex virus. J Exp Med. 1954 Aug 1;100(2):195–202. doi: 10.1084/jem.100.2.195. [DOI] [PMC free article] [PubMed] [Google Scholar]
- MORGAN C., ELLISON S. A., ROSE H. M., MOORE D. H. Structure and development of viruses observed in the electron microscope. II. Vaccinia and fowl pox viruses. J Exp Med. 1954 Sep 1;100(3):301–310. doi: 10.1084/jem.100.3.301. [DOI] [PMC free article] [PubMed] [Google Scholar]
- MURPHY J. S., BANG F. B. Observations with the electron microscope on cells of the chick chorio-allantoic membrane infected with influenza virus. J Exp Med. 1952 Mar;95(3):259–268. doi: 10.1084/jem.95.3.259. [DOI] [PMC free article] [PubMed] [Google Scholar]
- MURPHY J. S., KARZON D. T., BANG F. B. Studies of influenza A (pr8) infected tissue cultures by electron microscopy. Proc Soc Exp Biol Med. 1950 Apr;73(4):596–599. doi: 10.3181/00379727-73-17756. [DOI] [PubMed] [Google Scholar]
- PALADE G. E. A study of fixation for electron microscopy. J Exp Med. 1952 Mar;95(3):285–298. doi: 10.1084/jem.95.3.285. [DOI] [PMC free article] [PubMed] [Google Scholar]
- PORTER K. R., BLUM J. A study in microtomy for electron microscopy. Anat Rec. 1953 Dec;117(4):685–710. doi: 10.1002/ar.1091170403. [DOI] [PubMed] [Google Scholar]
- WATSON B. K., COONS A. H. Studies of influenza virus infection in the chick embryo using fluorescent antibody. J Exp Med. 1954 May 1;99(5):419–428. doi: 10.1084/jem.99.5.419. [DOI] [PMC free article] [PubMed] [Google Scholar]
- WYCKOFF R. W. G. Formation of the particles of influenza virus. J Immunol. 1953 Feb;70(2):187–196. [PubMed] [Google Scholar]