GENERATION OF RECOMBINANT ADENOVIRUS VECTORS WITH MODIFIED FIBERS FORALTERING VIRAL TROPISM

To expand the utility of recombinant adenovirus vectors for gene thera py applications, methods to alter native viral tropism to achieve cell -specific transduction would be beneficial. To this end, we are pursui ng genetic methods to alter the cell recognition domain of the adenovi rus fiber, To incorporate these modified fibers into mature virions, w e have developed a method based on homologous DNA recombination betwee n two plasmids, A fiber-deleted, propagation-defective rescue plasmid has been designed for recombination with a shuttle plasmid encoding a variant fiber gene. Recombination between the two plasmids results in the derivation of recombinant viruses containing the variant fiber gen e. To establish the utility of this method, we constructed a recombina nt adenovirus containing a fiber gene with a silent mutation, In addit ion, we generated an adenovirus vector containing chimeric fibers comp osed of the tail and shaft domains of adenovirus serotype 5 and the kn ob domain of serotype 3. This modification was shown to alter the rece ptor recognition profile of the virus containing the fiber chimera. Th us, this two-plasmid system allows for the generation of adenovirus ve ctors containing variant fibers. This method provides a rapid and faci le means of generating fiber-modified recombinant adenoviruses. In add ition, it should be possible to use this system in the development of adenovirus vectors with modified tropism to allow cell-specific target ing.