Abstract: A mutant virus for use as a vaccine for prophylaxis or therapy, wherein the genome of the virus is defective in respect of a gene essential for the production of infectious virus. In one aspect the mutant virus, e.g. a herpesvirus, e.g HSV-1 or HSV-2, is capable of protecting a susceptible species immunised therewith against infection by the corresponding wild-type virus. In another aspect, the mutant virus acts as a vector for an immunogenic protein derived from a pathogen, encoded by foreign DNA incorporated in the mutant virus. The mutant virus can be produced by a recombinant host cell which expresses a gene complementing the defect. The mutant virus can be infectious for the host to be protected, and the genetic defect can allow expression in the infected host of at least some of the viral genes, which can provoke a cell-mediated immune response. The defect can be in a glycoprotein gene such as gH.

Abstract: Live or killed preparations of attenuated mutant Neisseria bacteria, e.g. N. meningitidis, have the following mutations: (a) an auxotrophic attenuating mutation, e.g. AroA or AroB mutation, (b) a capsule mutation, e.g. synX or galE mutation, and also (c) a mutation which reduces bacterial recombination or exogenous DNA uptake, such as RecA and/or comA mutations. The mutants and their preparations can be used in vaccine compositions.

Abstract: A process of harvesting a herpesvirus from a cell culture infected therewith comprises treating said culture with a hypertonic aqueous salt solution to yield a virus suspension, e.g. to give improved yield of virus for live virus vaccine where otherwise cell-disruption might be used to harvest the virus by disrupting virus-infected cells. The harvesting step can be followed e.g. by nuclease treatment, diafiltration and lyophilisation.

Abstract: Hapten-carrier conjugates capable of eliciting anti-hapten antibodies in vivo by administering, in a therapeutic composition, are disclosed. Methods of preparing said conjugates and therapeutic compositions are also disclosed. Where the hapten is a drug of abuse, a therapeutic composition containing the hapten-carrier conjugate is particularly useful in the treatment of drug addiction, more particularly, cocaine addiction. Passive immunization using antibodies raised against conjugates of the instant invention is also disclosed. The therapeutic composition is suitable for co-therapy with other conventional drugs.

Abstract: A mutant virus for use as a vaccine, wherein the genome of the virus is defective in respect of a gene essential for the production 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, the 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 infectious 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.

Abstract: Culture of human oranimal herpesviruses, e.g. disabled mutant herpesviruses, can be carried out on primary cells which have been made recombinant so as to express a first gene that extends their culturable life and a second gene derived from the virus. The virus products can be used in vaccines or gene delivery to cells.