Control of Neurotropic MHV by Multifactorial Mechanisms
Cornelia C. Bergmann and Stephen A. Stohlman
from: Coronaviruses: Molecular and Cellular Biology (Edited by: Volker Thiel). Caister Academic Press, U.K. (2007)
Infection of the central nervous system (CNS) by mouse hepatitis virus (MHV) can result in fatal encephalitis. Rapid viral growth especially in neurons leads to death prior to effective immunity. Alternatively, MHV can induce an acute encephalomyelitis that resolves into a persistent infection under immune pressure. During both infections there is a coordinated innate immune response which, although unable to control virus, facilitates adaptive immunity during non-fatal infections. During non-lethal infection, virus is controlled by CD8+ T cells which use both perforin mediated cytolysis and IFN-g, depending upon the specific type of cell infected. In contrast to innate and anti-viral cellular mechanisms evident during acute infection, persistence is maintained via virus neutralizing antibody. CD8+ T cells loose anti-viral function as virus is controlled prior to complete virus elimination. Even memory T cells are insufficient to control persisting virus in the absence of antibody. Retention of virus specific antibody secreting within the CNS, despite their delayed appearance relative to T cells, implies local antibody production in providing protection throughout persistence read more ...