Measles virus-induced autoimmune reactions against brain antigen.

Recovery from viral infection is a result of very complex interactions between specific and nonspecific immune reactions and the infectious agent. A variety of immune mechanisms are undoubtedly important factors in this event and operate together in overcoming the infectious process. However, despite much available information about these viral defense mechanisms, it has proved remarkably difficult to assign a determinative role in vivo to any single antiviral immunological mechanism in recovery from a single viral disease, particularly since the immune response to the virus itself may frequently contribute to the pathology of the disease. Furthermore, if virus-induced immune responses are also directed against normal host components, this may set the stage for an autoimmune disease. In this context acute measles encephalomyelitis is of interest since in this disease autoimmune reactions against brain antigens have been observed and considered of pathogenetic importance. In this short review, virological and immunological findings of measles virus infections in a rat model in relation to autoimmune reactions will be presented and the mechanisms by which measles virus may alter host reactivity against self-antigens discussed.