HSV Amplicon Vectors

Name the two non-coding sequences derived from HSV that are included in HSV amplicon vectors. 

Saeki Y, Fraefel C, Ichikawa T, Breakefield XO, Chiocca EA (2001) Improved helper virus-free packaging system for HSV amplicon vectors using an ICP27-deleted, oversized HSV-1 DNA in a bacterial ardficial chromosome. Mol Ther 3 591-601. 

Bowers WJ, Howard DF, Federoff HJ (2000) Discordance between expression and genome transfer titering of HSV amplicon vectors Recommendation for standardized enumeration. Mol Ther 1 294-299. 

Epstein AL, Marconi P, Argnani R, Manservigi R. 2005. HSV-1 derived recombinant and amplicon vectors for gene transfer and gene therapy. Curr Gene Ther. 5 445-448. 

Liu, Y. X., Rabinovitch, A., SuarezPinzon, W., Muhkerjee, B., Brownlee, M., Edelstein, D. and Federoff, H. J. (1996). Expression of the bcl-2 gene from a defective HSV-1 amplicon vector protects pancreatic beta-cells from apoptosis. Hum. Gene Ther. 7, 1719-1726. 

The development of vectors based on HSV-1 has produced two different viral vector systems recombinant HSV-1 vectors and HSV-1 amplicons. 

The major problem of recombinant HSV-1 vectors is their cytopathic effect and the induction of an immune response by viral gene expression. The development of amplicon vectors and a helper vims-free packaging system has overcome this problem to a great extent (123-125). However, additional deletion of nonessential genes from the bac packaging system may be necessary to further prevent the cytotoxicity of this vector system. 

Johnston KM, Jacoby D, Pechan PA, et al. HSV/AAV hybrid amplicon vectors extend transgene expression in human glioma cells. Hum Gene Ther 1997 ... 

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