Systematic lactose-functionalization of amphiphilic octaamine macrocycle as a gene carrier. Optimization of the charge, size, toxicity, and receptor factors for hepatocyte targeting

    loading  Checking for direct PDF access through Ovid


We investigated the transfection properties of singly and triply lactose-functionalized derivatives, Lac(1) and Lac(3), and non-glycosidated one, Lac(0), of calix[4]resorcarene-based amphiphilic octaamine 1 in light of those previously reported for more extensively glycosidated compounds Lac(5) and Lac(8). They all strongly bind to the luciferase-encoding plasmid DNA pCMVluc (7040 base-pairs) with a saturation stoichiometry of Lac(n)/P 0.5 (n = 0, 1, or 3) or 0.7 (n = 5 or 8), where P stands for a phosphate moiety of the plasmid DNA. The resulting carrier–DNA conjugates are positively charged and monomeric (monomolecular with respect to DNA) as such when n = 0 or 1, neutral and monomeric when n = 3, or neutral and aggregated when n = 5 or 8. Transfection of HeLa (uterine) and HepG2 (hepatic) cell lines shows a general trend of decreasing luciferase expression efficiencies (E) in lively cells as well as cytotoxicities with increasing n's. The cell selectivities for HepG2 over HeLa sharply increase with increasing n's; EHepG2 / EHeLa = 0.3, 0.6, 7, 14, and 120 for Lac(0), Lac(1), Lac(3), Lac(5), and Lac(8), respectively, as a result of specific receptor pathway involving the asialoglycoprotein receptors on the hepatic (HepG2) cell surfaces and clustering lactose moieties of the carrier–DNA conjugates. The toxicity-corrected, overall efficiency of gene delivery to hepatocytes is optimized at Lac(3), which forms compactly packed (˜ 40 nm), charge-masked (ξ 0 mV), and less toxic virus-like particles capable of receptor-mediated hepatocyte targeting.

    loading  Loading Related Articles