Hepatitis delta virus compositions and expression vectors

摘要

Hepatitis delta is used as a vector for inhibition of viral infection and to express proteins in vivo in a cell-specific manner. The scope of delta's use as a vector is broadened in the present invention in several important ways. For example, a delta RNA genome capable of self-replication is enlarged to carry additional information, either coding for messenger RNA for a protein, or for a targeted ribozyme, which can be delivered to liver cells using delta's normally infectious properties, or to other cell types using chimeric delta viral agents carrying altered surface proteins. In another embodiment, the delta vector is made self-limiting, so that its role in delivering targeted information is separated from its viral property of unlimited infectious replication. Targeting is achieved through the use of sequences flanking the delta sequences that have affinity for sites on RNA to be cleaved.