期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1982
卷号：79
期号：4
页码：1298-1302
DOI：10.1073/pnas.79.4.1298
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：A number of field isolates of reovirus 3 were examined to determine their relative neurovirulence after intracerebral inoculation. One isolate was found that had decreased neurovirulence. This "avirulent" strain showed the typical type 3 neural tropism but grew significantly less well in brain tissue than T3 (Dearing) and the other type 3 reoviruses. The avirulent virus was not temperature-sensitive, and its yield in mouse L cells in vitro was similar to that of the laboratory strains. To determine the reason that this clone was avirulent, we isolated a series of reassortant progeny clones from crosses between the avirulent strain and T1 (Lang) and T3 (Dearing). Using these reassortants, we showed that avirulence was a property of the M 2 gene segment. The M2 segment was also responsible for conferring greater sensitivity to chymotryptic digestion on the avirulent strain, compared to more virulent strains. Prior studies have determined that the localization of virus in different cell types in the brain (tropism) is a property of the viral hemagglutinin, the product of the S1 RNA genome segment. Our studies thus indicate that the basis for relative neurovirulence does not reside in the viral hemagglutinin and clearly illustrate the multigenic nature of neurovirulence.
