64 F. B. BANG 



F. Fluorescent Antibody Staining 87 



1 . Mumps 88 



2. Influenza 88 



3. Fowl Plague 88 



G. Incomplete Virus 89 



IX. Adenoviruses 89 



A. Cytochemistry 89 



B. Electron Microscopy 90 



X. Poliomyelitis and Other Neurotropic Viruses 91 



A. Nerve Cells 91 



1. Classic Findings 91 



2. Tissue Culture 92 



B. Epithelial Cells and Fibroblasts 92 



1. Morphological Changes Observed in Living Cells 92 



2. Relation to Virus Release 93 



3. Other Findings 94 



C. Encephalitis 95 



XI. Tumor Viruses 95 



A. Rous Chicken Sarcoma 96 



1. Effect on Cells in Tissue Culture 96 



2. Electron Microscopy 97 



3. Localization of Virus 98 



B. Mammary Tumors of Mice 99 



1. "Inclusion" and Virus Particles 99 



2. Morphological Evidence of Virus Release 100 



C. Warts (Human Papillomas) 101 



D. Frog Adenocarcinoma 101 



XII. Discussion and Conclusions 103 



References 105 



I. Introduction 



The flood of new studies on cell pathology which has followed the introduc- 

 tion of phase microscopy of living cells, the electron microscopy of thin 

 sections, the staining of viral antigens with fluorescent antibody, and, finally, 

 the discovery of a variety of new viruses of man and other animals is suffi- 

 cient reason for an attempt at a complete reorientation of our ideas of cell 

 pathology. There remains a series of classic contributions which have been 

 thoroughly reviewed in the past (Ludford, 1951; Cowdry, 1928; Eivers, 

 1928), and which this review will not attempt to replace. However, as infor- 

 mation concerning the action of virus and reaction of the cell accumulates, 

 a new framework of reference is needed. Reappraisal could hopefully stimu- 

 late further work, but at the least it may designate the many situations in 

 which recorded observations are lacking. 



We will attempt to describe and analyze the morphological events which 

 are involved in the absorption of virus to a cell, in the action of and reaction 

 to the virus in the periphery of the cell, in the cytoplasm and its organelles, 



