title: Aminoclay as a highly effective cationic vehicle for enhancing adenovirus-mediated gene transfer through nanobiohybrid complex formation.
abstract: Electrostatic complexation of adenovirus (Ad) with cationic lipids or polymers has been shown to be an effective means for overcoming the limitations of adenoviral vectors and enhancing gene-transfer efficacy. However, such complexation causes cytotoxicity, limiting the use of this strategy. The present study explored the potential of 3-aminopropyl functionalized magnesium phyllosilicate (aminoclay) as a cationic vehicle for improving Ad-mediated gene transfer without inducing cytotoxicity. Aminoclay complexation produced a dose-dependent increase in Ad-mediated transgene expression in both Ad infection-sensitive and -refractory cells, thereby greatly lowering the Ad dose required for transgene expression. Unlike the case for cationic lipids (Lipofectamine) or polymers (Polybrene), the enhancement effect of aminoclay was not accompanied by significant cytotoxicity regardless of cell lines and it was not observed for nonviral plasmid vectors. Physical characterization studies revealed that nanobiohybrid complexes formed between aminoclay and Ad particles through electrostatic interactions, creating aggregates of Ad particles whose surface was shielded with aminoclay nanosheet oligomers. It appears that aminoclay complexation changes the surface charge of Ad particles from a negative to a highly positive value and thus increases Ad binding to cellular membranes, thereby providing an additional cellular entry mechanism, namely caveolae-dependent endocytosis. Aminoclay-Ad nanobiohybrids may serve as a next-generation efficient, versatile and biocompatible gene-delivery carrier.
  
  
  
  Electrostatic complexation of adenovirus with cationic materials has been shown to be an effective means for enhancing gene-transfer efficacy in vitro. However, such complexation causes cytotoxicity, limiting the use of this strategy. The present study explored the potential of a synthesized organoclay 3-aminopropyl functionalized magnesium phyllosilicate (aminoclay) as a cationic vehicle for improving Ad-mediated gene transfer. Our data indicate that nanobiohybrid complexes form between aminoclay and Ad particles through electrostatic interactions, thereby greatly enhancing Ad-mediated gene transfer. Unlike the case for either cationic lipids or cationic polymers, the enhancement effect of aminoclay was not accompanied by significant cytotoxicity regardless of cell lines. Our findings in this work highlight that aminoclay-Ad nanobiohybrids may serve as a next-generation efficient and biocompatible gene-delivery carrier.
authors.affiliation: Department of Integrative Bioscience and Bioengineering, Sejong University, Seoul, 98 Kunja-dong, Kwangjin-gu, Seoul 05006, Republic of Korea.
authors.forename: Soo-Yeon
authors.initials: SY
authors.lastname: Kim
authors.affiliation: Genitourinary Cancer Branch, Research Institute, National Cancer Center, 323 Ilsan-ro, Ilsandong-gu, Goyang-si, Gyeonggi-do 10408, Republic of Korea.
authors.forename: Sang-Jin
authors.initials: SJ
authors.lastname: Lee
authors.affiliation: College of Pharmacy, Dongguk University-Seoul, Siksa-dong, Ilsan-Donggu, Goyang, Gyunggi-do 10326, Republic of Korea. Electronic address: hkhan@dongguk.edu.
authors.forename: Hyo-Kyung
authors.initials: HK
authors.lastname: Han
authors.affiliation: Department of Integrative Bioscience and Bioengineering, Sejong University, Seoul, 98 Kunja-dong, Kwangjin-gu, Seoul 05006, Republic of Korea. Electronic address: sjlim@sejong.ac.kr.
authors.forename: Soo-Jeong
authors.initials: SJ
authors.lastname: Lim
mesh_terms: D000256:Adenoviridae / Q000378:metabolism*; D000538:Aluminum Silicates / Q000737:chemistry*; D000588:Amines / Q000737:chemistry*; D002412:Cations; D016923:Cell Death; D045744:Cell Line, Tumor; D000077215:Clay; D004705:Endocytosis; D018014:Gene Transfer Techniques; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006801:Humans; D008546:Melanoma, Experimental / Q000473:pathology; D053758:Nanoparticles / Q000737:chemistry*; D019076:Transgenes
chemical_list: D000538:Aluminum Silicates; D000588:Amines; D002412:Cations; D049452:Green Fluorescent Proteins; D000077215:Clay
keywords: 3-Aminopropyl functionalized magnesium phyllosilicate; Adenovirus; Cationic; Gene delivery; Nanobiohybrid