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Biotech / Medical : Gene therapy -- Ignore unavailable to you. Want to Upgrade?

To: Mike McFarland who wrote (168)	9/29/1999 9:30:00 PM
From: Mike McFarland	Read Replies (1) \| Respond to of 319

I got a note asking what a MAb trial was-- the point I wanted to ask was this, and then I'll need some help from the biotech guys: Biotech is often about deleting or adding a protein...or in gene therapy, going right to the gene responsible for that protein. So I wanted to point out that certainly there have been violent immune responses to other types of therapy--MAb's, monoclonal antibodies, the so called magic bullets we are always hearing about--these would be the sort of thing that has probably killed some patients in early trials from severe immune response, right? I don't want to sound like I am diminishing the importance of this fellow's death, it must have been a terrible day for everybody involved, I even started to cry when I read the article at the Washington Post. However, I would imagine with experimental therapies there are often surprise deaths like this one. How often does a cancer patient die from the therapy before the cancer actually kills him, it must happen fairly often. The CEGE thread is fairily active, I'll see what the reaction is over there--seems like for every couple steps forward with Gene Therapy, there is a step back...this must have been an incredible disappointment for the scientists at Upenn.

To: Mike McFarland who wrote (168)	9/30/1999 5:46:00 AM
From: SnowShredder	Respond to of 319

Hi Mike, Thanks for the sad, yet interesting information...I wonder if they are going to release more details. In return, I contribute this abstract...Best of Luck, Where'd He Go? <<<<<<<<<>>>>>>>>> J Virol 1999 Sep;73(9):7582-9 An adenovirus-Epstein-Barr virus hybrid vector that stably transforms cultured cells with high efficiency. Tan BT, Wu L, Berk AJ Department of Microbiology and Molecular Genetics, Molecular Biology Institute, University of California, Los Angeles, Los Angeles, California 90095, USA. EBV episomes are nuclear plasmids that are stably maintained through multiple cell divisions in primate and canine cells (J. L. Yates, N. Warren, and B. Sugden, Nature 313:812-815, 1985). In this report, we describe the construction and characterization of an E1-deleted recombinant adenovirus vector system that delivers an EBV episome to infected cells. This adenovirus-EBV hybrid vector system utilizes Cre-mediated, site-specific recombination to excise an EBV episome from a target recombinant adenovirus genome. We demonstrate that this vector system efficiently delivers the EBV episome and stably transforms a large fraction of infected canine D-17 cells. Using a colony-forming assay, we demonstrate stable transformation of 37% of cells that survive the infection. However, maximal transformation efficiency is achieved at doses of the E1-deleted recombinant adenoviruses that are toxic to the infected cells. Consequently, E1-deleted vector toxicity imposes a limitation on our current vector system. PMID: 10438848, UI: 99370202