Cross-linked low molecular weight glycopeptide-mediated gene delivery: Relationship between DNA metabolic stability and the level of transient gene expression in vivo

✍ Scribed by Yongsheng Yang; Youmie Park; Shouchin Man; Yahong Liu; Kevin G. Rice

• Publisher: John Wiley and Sons
• Year: 2001
• Tongue: English
• Weight: 231 KB
• Volume: 90
• Category: Article
• ISSN: 0022-3549
• DOI: 10.1002/jps.1152

✦ Synopsis

DNA co-condensates were formed by reacting [ 125 I]DNA with an admixture of a high-mannose glycopeptide (Man9-CWK 18 ) and either of two poly (ethylene glycol) peptides (PEG-VS-CWK 18 or PEG-SS-CWK 18 ) followed by crosslinking with 6±50 mol equiv of glutaraldehyde. [ 125 I]DNA co-condensates were administered intravenously in mice to determine the in¯uence of peptide DNA formulation parameters on speci®c targeting to Kupffer cells. Optimal targeting to Kupffer cells required the combined use of 50 mol % Man9-CWK 18 and PEG-CWK 18 to mediate speci®c recognition by the mannose receptor to Kupffer cells. The cellular uptake of cross-linked Man9-CWK 18 /PEG-CWK 18 DNA co-condensates was receptor mediated since Kupffer cell targeting was inhibited by pre-administration of Manbovine serum albumin (BSA) but not BSA. An optimized formulation targeted 60% of the dose to the liver, with 80% of the liver-targeted DNA localized to Kupffer cells. Crosslinking with either 6, 15, or 50 mol equiv of glutaraldehyde led to a corresponding decrease in the metabolism rate of DNA in liver as measured by half-live-of 4, 6, and 39 h, respectively. Tail vein dosing of 50 mg of DNA co-condensates cross-linked with 6 mol equiv of glutaraldehyde produced detectable levels of human a 1 -antitrypsin in blood after 12 h, which peaked at day six and persisted for 10 days. The level of human a 1 -antitrypsin was elevated two-fold each day when dosing with DNA co-condensates cross-linked with 15 mol equiv of glutaraldehyde, revealing a correlation between the metabolic stability of the DNA in liver and level of gene expression. In addition to possessing greater metabolic stability, DNA co-condensates cross-linked with 50 mol equiv of glutaraldehyde, but lacking a targeting ligand, avoided rapid liver uptake and possessed a prolonged pharmacokinetic half-life, providing insight into a means to target DNA condensates to peripheral tissues.