Polycation-based DNA complexes for tumor-targeted gene delivery in vivo

✍ Scribed by Ralf Kircheis; Susanne Schüller; Sylvia Brunner; Manfred Ogris; Karl-Heinz Heider; Wolfgang Zauner; Ernst Wagner

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 651 KB
• Volume: 1
• Category: Article
• ISSN: 1099-498X
• DOI: 10.1002/(sici)1521-2254(199903/04)1:2<111::aid-jgm22>3.0.co;2-y

✦ Synopsis

Background Ef®cient and target-speci®c in vivo gene delivery is a major challenge in gene therapy. Compared to cell culture application, in vivo gene delivery faces a variety of additional obstacles such as anatomical size constraints, interactions with biological ¯uids and extracellular matrix, and binding to a broad variety of non-target cell types.

Methods Polycation-based vectors, including adenovirus-enhanced transferrinfection (AVET) and transferrin-polyethylenimine (Tf-PEI), were tested for gene delivery into subcutaneously growing tumors after local and systemic application. DNA biodistribution and reporter gene expression was measured in the major organs and in the tumor.

Results Gene transfer after intratumoral application was 10±100 fold more ef®cient with Tf-PEI/DNA or AVET complexes in comparison to naked DNA. Targeted gene delivery into subcutaneously growing tumors after systemic application was achieved using electroneutral AVET complexes and sterically stabilized PEGylated Tf-PEI/DNA complexes, whereas application of positively charged polycation/DNA complexes resulted in predominant gene expression in the lungs and was associated by considerable toxicity.

Conclusion

For systemic application, the physical and colloidal parameters of the transfection complexes, such as particle size, stability, and surface charge, determine DNA biodistribution, toxicity, and transfection ef®cacy. By controlling these parameters, DNA biodistribution and gene expression can be targeted to different organs.