Format

Send to

Choose Destination
J Gene Med. 2006 Jan;8(1):35-41.

An ex vivo human model system to evaluate specificity of replicating and non-replicating gene therapy agents.

Author information

1
Department of Therapeutic Gene Modulation, Groningen University Institute for Drug Exploration, 9713 AV Groningen, The Netherlands. m.g.rots@rug.nl

Abstract

BACKGROUND:

Inefficiency, aspecificity and toxicity of gene transfer vectors hamper gene therapy from showing its full potential. On this basis significant research currently focuses on developing vectors with improved infection and/or expression profiles. Screening assays with validity to the clinical context to determine improved characteristics of such agents are not readily available since this requires a close relationship to the human situation. We present a clinically relevant tissue slice technology to preclinically test improved vector characteristics.

METHODS:

Slices were prepared from rat, mouse and human liver samples and from tumor tissue. Specificity of gene expression and replication was determined by infecting target and non-target tissue slices with transcriptionally retargeted adenoviruses and oncolytic viruses.

RESULTS:

Using rat liver slices, we demonstrate efficient knob-mediated adenoviral infectivity. A favorable tumor-on/liver-off profile, resembling in vitro and mouse in vivo data, was shown for a tumor-specific transcriptionally retargeted adenovirus by infecting slices prepared from tumor or liver tissue. Similar liver-off data were found for mouse, rat and human samples (over 3-log lower activity of the tumor-specific promoter compared to cytomegalovirus (CMV)). More importantly, we show that this technology when applied to human livers is a powerful tool to determine aspecific replication of oncolytic viruses in liver tissue. A 2- to 6-log reduction in viral replication was observed for a tumor-specific oncolytic virus compared to the wild-type adenovirus.

CONCLUSIONS:

The precision-cut tissue slice technology is a powerful method to test specificity and efficiency of gene transfer as well as of viral replication using human tissue.

PMID:
16044485
DOI:
10.1002/jgm.815
[Indexed for MEDLINE]

Supplemental Content

Loading ...
Support Center