Utility of intraperitoneal administration as a route of AAV serotype 5 vector-mediated neonatal gene transfer

✍ Scribed by Tsuyoshi Ogura; Hiroaki Mizukami; Jun Mimuro; Seiji Madoiwa; Takashi Okada; Takashi Matsushita; Masashi Urabe; Akihiro Kume; Hiromi Hamada; Hiroyuki Yoshikawa; Yoichi Sakata; Keiya Ozawa

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 293 KB
• Volume: 8
• Category: Article
• ISSN: 1099-498X
• DOI: 10.1002/jgm.916

✦ Synopsis

Abstract

Background

Gene transfer into a fetus or neonate can be a fundamental approach for treating genetic diseases, particularly disorders that have irreversible manifestations in adulthood. Although the potential utility of this technique has been suggested, the advantages of neonatal gene transfer have not been widely investigated. Here, we tested the usefulness of neonatal gene transfer using adeno‐associated virus (AAV) vectors by comparing the administration routes and vector doses.

Methods

To determine the optimal administration route, neonates were subjected to intravenous (iv) or intraperitoneal (ip) injections of AAV5‐based vectors encoding the human coagulation factor IX (hfIX) gene, and the dose response was examined. To determine the distribution of transgene expression, vectors encoding lacZ or luciferase (luc) genes were used and assessed by X‐gal staining and in vivo imaging, respectively. After the observation period, the vector distribution across tissues was quantified.

Results

The factor IX concentration was higher in ip‐injected mice than in iv‐injected mice. All transgenes administered by ip injection were more efficiently expressed in neonates than in adults. The expression was confined to the peritoneal tissue. Interestingly, a sex‐related difference was observed in transgene expression in adults, whereas this difference was not apparent in neonates.

Conclusions

AAV vector administration to neonates using the ip route was clearly advantageous in obtaining robust transgene expression. Vector genomes and transgene expression were observed mainly in the peritoneal tissue. These findings indicate the advantages of neonatal gene therapy and would help in designing strategies for gene therapy using AAV vectors. Copyright © 2006 John Wiley & Sons, Ltd.