TLR3 and encephalitis: In terms of severe neuroinflammation in TLR3−/− mice, the expression levels of cytokines and chemokines within the CNS can be required for further explain encephalitis, because encephalitis caused by neurotrophic viruses is indirectly derived from CNS degeneration caused by robust immunological responses, such as the uncontrolled secretion of cytokines and chemokines, and resultant activation of microglia and astrocytes [7]–[9].