Cytopathogenic Effect of Poliomyelitis Viruses In vitro on Human Embryonic Tissues. ∗

Summary and discussion

The experiments which have been described demonstrate the capacity of the Lansing and Brunhilde strains of poliomyelitis virus to cause cell injury and death. This cytopathogenic property is revealed (1) by degenerative changes produced in infected tissue fragments in flask cultures and apparent on histologic examination; (2) by failure of such tissue fragments to exhibit normal cell migration when explanted to plasma cultures; (3) by degeneration of newly emigrated cells in roller-tube cultures; (4) by decreased acid production by infected cells. The conclusion that certain of these manifestations of injury are induced as a result of infection by the virus is further supported by the fact that type specific immune serum prevents their development. These phenomena are of interest from two general points of view. First, they leave no doubt that poliomyelitis virus in vitro can multiply in cells other than those of the nervous system and cause profound injury of such cells. Secondly, they provide criteria by which the presence of the virus can be recognized in vitro and hence may afford a basis of technics for isolating virus from patients or animals, for the quantitative assay of virus, for serologic typing and possibly for the screening of chemotherapeutic and antibiotic substances. Further study will be required of the reliability and practicability of the application of these phenomena to such ends.†