VIRAL DEFECTIVE VACCINE PRODUCED BY TRANSCOMPLEMENTING CELL LINE

摘要

A mutant virus for use as a vaccine, wherein the genome of the virus is defective in respect of a gene essential for the pro- duction of infectious virus. In one aspect the mutant virus is capable of protecting a susceptible species immunized therewith against infection by the corresponding wild-type virus. In another aspect, t he mutant virus acts as a vector for an immunogenic protein derived from a pathogen and which is encoded by foreign DNA incorporated in the mutant virus. The mutant virus can be produced in a recombinant host cell which expresses a gene complementing the defect. The mutant virus is preferably infec- tious for the host to be protected, but the defective gene allows expression in the infected host of at least some of the viral genes, which can provoke a cell-mediated immune response.