Measles infection of the central nervous system.

Central nervous system (CNS) complications occurring early and late after acute measles are serious and often fatal. In spite of functional cell-mediated immunity and high antiviral antibody titers, an immunological control of the CNS infection is not achieved in patients suffering from subacute sclerosing panencephalitis (SSPE). The known cellular receptors for measle virus (MV) in humans, CD46 and CD150 (signaling lymphocyte activation molecule, SLAM), are important components of the viral tropism by mediating binding and entry to peripheral cells. Because neural cells do not express SLAM and only sporadically CD46, virus entry to neural cells, and spread within the CNS, remain mechanistically unclear. Mice, hamsters, and rats have been used as model systems to study MV-induced CNS infections, and revealed interesting aspects of virulence, persistence, the immune response, and prerequisites of protection. With the help of recombinant MV and mice expressing transgenic receptors, questions such as receptor-dependent viral spread, or viral determinants of virulence, have been investigated. However, many questions concerning the human MV-induced CNS diseases are still open.