Abstract: A mammalian expression system comprising an attenuated, recombinant Ranavirus that has at least one foreign expression element using a unique combination of mammalian transcriptional and translational enhancement elements is disclosed. In other contemplated embodiments, a mammalian expression system comprising a virus, wherein the virus is engineered to express at least two vaccine antigens is disclosed. In addition, methods of delivering human antigens to a mammal are disclosed that include: providing a non-mammalian virus, engineering a recombinant virus that can express at least one foreign molecule by modifying the non-mammalian virus, and using the recombinant Ranavirus to express and deliver foreign antigens to a mammal.

Abstract: A mammalian expression system comprising an attenuated, recombinant ranavirus strain that has at least one expression element is disclosed. A method of delivering antigens to a mammal is disclosed that includes: providing a mammalian expression system comprising an attenuated, recombinant ranavirus strain that has at least one expression element; and administering to the mammal a therapeutic amount of the attenuated, recombinant ranavirus strain that has at least one expression element.

Abstract: A vaccine vector comprising an attenuated, recombinant ranavirus that has at least one foreign expression element is disclosed. In other contemplated embodiments, a vaccine vector comprising a virus, wherein the virus is engineered to express at least two vaccine antigens is disclosed. In addition, methods of delivering human antigens to a mammal are disclosed that include: providing a non-mammalian virus, engineering a recombinant virus that can express at least one foreign molecule by modifying the non-mammalian virus, and using the recombinant ranavirus to deliver human antigens to a mammal.

Abstract: The present invention provides reagents and methods for improved homologous recombination.

Abstract: The present invention provides reagents and methods for improved homologous recombination.

Abstract: The present invention relates to vaccines having an increased level of safety comprising recombinant vaccinia viruses containing an inactivated E3L region. The invention also relates to methods for stimulating a protective immune response in an immunized host using the vaccines of the invention. The invention is based on the discovery that vaccinia virus mutants having deletions in the E3L region exhibit dramatically reduced pathogenesis while remaining highly immunogenic. In addition, the invention relates to modified recombinant vaccinia viruses engineered to express heterologous polypeptides and the use of such viruses in vaccines designed to stimulate a protective immune response against such polypeptides in a host. The invention further relates to an interferon-sensitive recombinant vaccinia virus with broad host range wherein a salamander eIF2? is inserted into the viral genome in place of at least a portion of the E3L gene.

Abstract: The present invention relates to vaccines having an increased level of safety comprising recombinant vaccinia viruses containing an inactivated E3L region. The invention also relates to methods for stimulating a protective immune response in an immunized host using the vaccines of the invention. The invention is based on the discovery that vaccinia virus mutants having deletions in the E3L region exhibit dramatically reduced pathogenesis while remaining highly immunogenic. In addition, the invention relates to modified recombinant vaccinia viruses engineered to express heterologous polypeptides and the use of such viruses in vaccines designed to stimulate a protective immune response against such polypeptides in a host. The invention further relates to an interferon-sensitive recombinant vaccinia virus with broad host range wherein a salamander eIF2? is inserted into the viral genome in place of at least a portion of the E3L gene.