Viral spread in the presence of neutralizing antibody: mechanisms of persistence in foamy virus infection.

Several viruses were categorized on the basis of their ability to spread from cell to contiguous cell and form plaques in the presence of antiviral antibody. Herpes simplex virus, cytomegalovirus, and vaccinia, measles, and foamy viruses were able to spread in the presence of neutralizing antibody, whereas coxsackievirus, encephalomyocarditis virus, vesicular stomatitis virus, mumps virus, and simian virus 5 failed to spread. A detailed study of one of these virus groups (simian foamy viruses) suggested that the ability of these viruses to spread from cell to cell in the presence of antiviral antibody, the failure of antiviral antibody and complement to lyse infected cells, and the poor induction and relative resistance of these viruses to the antiviral action of interferon contribute to the persistent nature of this infection.