Differences between the intracellular polypeptides of measles and subacute sclerosing panencephalitis virus

Abstract

MEASLES virus is thought to be responsible for the rare childhood disease subacute sclerosing panencephalitis (SSPE)^1–4, which is a slowly progressive degenerative disease of the central nervous system occurring several years after an acute episode of measles. The physical and serological characteristics of SSPE virions isolated following cocultivation of infected brain cells bears a striking similarity to conventional measles virus^1,2. Some SSPE strains, however, have been found to differ from measles virus in biological properties and RNA homologies^5–10. There is also a report comparing the polypeptides of measles and SSPE virions in which an aberrant migration of the M polypeptide was noted¹¹. Unfortunately, no polypeptide profiles were presented and better documentation of the finding has not been published. Several theories have been advanced to explain the mechanism by which measles virus can persist and produce SSPE. These include an abnormal host immune response to a measles virus infection, a second viral agent acting in coinfection with a measles-like virus, and a mutation of the parental measles virus^12,13. In order to gain further insight into the nature of SSPE, we have compared the intracellular polypeptides of five SSPE isolates with those of measles virus.