• KSBB Journal
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• 제19권5호
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• pp.341-347
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• 2004

Several gene delivery therapies are being developed for treatment of serum protein deficiency. EPO is one of the most promising therapeutic agent for this treatment which is currently being investigated in depth. This study has the ultimate purpose of improving the gene delivery system for an increase of red blood cell production. A plasmid DNA was constructed smaller than other plasmids for an increase in penetration into animal cells, and two genes were cloned into each vector as a co-delivery system to express erythropoietin, and interluekin-3 or thrombopoietin, which can act on erythroid cell, thus activating hematopoiesis synergically. This co-delivery system has an advantage of decreasing the labour required for industrial production of DNA vaccine. A new plasmid vector, pVAC, in size 2.9 kb, was constructed with the essential parts from PUC 19 and pSectagB, which is much smaller than other plasmid vector and is the size of 2.9 kb. Co-delivery system was constituted by cloning human erythropoietin with each of human interluekin-3 gene or human thrombopoietin gene into both pVAC and pSectagB. As a result, the transfection efficiency of pVAC was higer than that of pSectagB in vitro, and hematocrit level of the mice injected with pVAC is higher than that of other mice. And co-delivery system, made of several plasmid DNAs, was expressed in vitro.

• International Journal of Oral Biology
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• 제38권4호
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• pp.155-160
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• 2013

The major issue in the development of nucleic acid based therapeutics is the inefficient delivery of these agents into cells. We prepared cholesterol conjugated spermine and evaluated its usefulness as a delivery modality for antisense oligonucleotides in HeLa-Luc cells. A 2'-O-methyl antisense oligonucleotide sequence, designed to correct splicing at an aberrant intron inserted into a normal luciferase reporter gene, was used for complex formation with cholesterol conjugated spermine. Effective delivery of this antisense agent into nucleus would results in the expression of a luciferasereporter gene product. The cholesterol-spermine formed stable complexes with the antisense oligonucleotide and showed modest delivery activity. Furthermore, this delivery activity was maintained even in the presence of serum proteins, mimicking in vivo conditions. Cholesterol-spermine thus has potential as a delivery system for antisense oligonucleotides into cells.

• Korean Chemical Engineering Research
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• 제47권5호
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• pp.538-545
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• 2009

본 총설에서는 주사형프로브현미경의 원리와 응용에 관하여 간략히 설명하고 최근 본 그룹에 의하여 활발하게 연구되고 있는 나노탐침과 AFM(원자간력현미경 atomic force microscopy)을 이용한 저침습성(low-invasive) 단일세포 조작기술과 고효율 유전자 도입기술을 소개하고자 한다. 시판 AFM 탐침을 침상구조로 가공한 나노탐침과 AFM을 이용하였을 경우, 탐침의 세포삽입의 성공여부를 force-distance curve 상의 척력소실의 유무로 판단할 수 있다. 침상 나노탐침을 사용하면 대부분의 세포에서 80~90%의 고효율 세포삽입이 가능하여 마이크로인젝션용 미세관을 이용하는 경우보다 세포삽입효율이 높았다. 또한 나노탐침의 직경이 400 nm 이하의 경우에는 세포 종류에 관계없이 장시간 나노탐침의 삽입에도 세포활성에 큰 영향이 없었다. 침상나노탐침을 이용하여 DNA를 도입하였을 경우에도 기존의 DNA 도입방법과 비교하여 높은 도입효율과 유전자 발현율로 DNA를 도입할 수 있는 가능성을 확인하였다.

• Bulletin of the Korean Chemical Society
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• 제34권9호
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• pp.2589-2593
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• 2013

Gene therapy using nonviral gene delivery carriers has focused on the development and modification of synthetic carriers such as liposomes and polymers. Most polymers that are commercially used are taking advantage of their polycationic character which allows not only strong ligand-DNA affinity but also competent cell penetration. Despite the relatively high transfection efficiencies, high cytotoxicity is continuously pointed out as one of the major shortcomings of polycationic polymers such as PEI. Studies on the utilization of peptides have therefore been carried out recently to overcome these problems. For these reasons, the human transcription factor Hph-1, which is currently known as a protein transduction domain (PTD), was investigated in this study to evaluate its potential as a gene delivery carrier. Although its transfection efficiency was about 10-fold lower than PEI, it displayed almost no cytotoxicity even at concentrations as high as $100{\mu}M$. Hph-1 was oxidatively polymerized to yield poly-Hph-1. The cell viability of poly-Hph-1 transfected U87MG and NIH-3T3 cells was almost as high as the control (untreated) groups, and the transfection efficiency was about 10-fold higher than PEI. This study serves as a preliminary evaluation of Hph-1 and encourages further investigation.

• Journal of Microbiology and Biotechnology
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• 제22권6호
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• pp.866-871
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• 2012

A novel cholesterol-based cationic lipid containing a tri-2-hydroxyethylamine head group and ether linker (Chol-THEA) was synthesized and examined as a potent gene delivery vehicle. In the preparation of cationic liposome, the addition of DOPE as helper lipid significantly increased the transfection efficiency. To find the optimum transfection efficiency, we screened various weight ratios of DOPE and liposome/DNA (N/P). The best transfection efficiency was found at the Chol-THEA:DOPE weight ratio of 1:1 and N/P weight ratio of 10~15. Most of the plasmid DNA was retarded by this liposome at the optimum N/P weight ratio of 10. The transfection efficiency of Chol-THEA liposome was compared with DOTAP, Lipofectamine, and DMRIE-C using the luciferase assay and GFP expression. Chol-THEA liposome with low toxicity had better or similar potency of gene delivery compared with commercial liposomes in COS-7, Huh-7, and MCF-7 cells. Therefore, Chol-THEA could be a useful non-viral vector for gene delivery.

• BMB Reports
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• 제53권11호
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• pp.565-575
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• 2020

Gene therapy is emerging as a treatment option for inherited genetic diseases. The success of this treatment approach greatly depends upon gene delivery vectors. Researchers have attempted to harness the potential of viral vectors for gene therapy applications over many decades. Among the viral vectors available, gutless adenovirus (GLAd) has been recognized as one of the most promising vectors for in vivo gene delivery. GLAd is constructed by deleting all the viral genes from an adenovirus. Owing to this structural feature, the production of GLAd requires a helper that supplies viral proteins in trans. Conventionally, the helper is an adenovirus. Although the helper adenovirus efficiently provides helper functions, it remains as an unavoidable contaminant and also generates replication-competent adenovirus (RCA) during the production of GLAd. These two undesirable contaminants have raised safety concerns and hindered the clinical applications of GLAd. Recently, we developed helper virus-free gutless adenovirus (HF-GLAd), a new version of GLAd, which is produced by a helper plasmid instead of a helper adenovirus. Utilization of this helper plasmid eliminated the helper adenovirus and RCA contamination in the production of GLAd. HF-GLAd, devoid of helper adenovirus and RCA contaminants, will facilitate its clinical applications. In this review, we discuss the characteristics of adenoviruses, the evolution and production of adenoviral vectors, and the unique features of HF-GLAd as a new platform for gene therapy. Furthermore, we highlight the potential applications of HF-GLAd as a gene delivery vector for the treatment of various inherited genetic diseases.

• Archives of Pharmacal Research
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• 제25권3호
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• pp.229-239
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• 2002

Recent progress in understanding the molecular basis of cancer brought out new materials such as oligonucleotides, genes, peptides and proteins as a source of new anticancer agents. Due to their macromolecular properties, however, new strategies of delivery for them are required to achieve their full therapeutic efficacy in clinical setting. Development of improved dosage forms of currently marketed anticancer drugs can also enhance their therapeutic values. Currently developed delivery systems for anticancer agents include colloidal systems (liposomes, emulsions, nanoparticles and micelles), polymer implants and polymer conjugates. These delivery systems have been able to provide enhanced therapeutic activity and reduced toxicity of anticancer agents mainly by altering their pharmacokinetics and biodistribution. Furthermore, the identification of cell-specific receptor/antigens on cancer cells have brought the development of ligand- or antibody-bearing delivery systems which can be targeted to cancer cells by specific binding to receptors or antigens. They have exhibited specific and selective delivery of anticancer agents to cancer. As a consequence of extensive research, clinical development of anticancer agents utilizing various delivery systems is undergoing worldwide. New technologies and multidisciplinary expertise to develop advanced drug delivery systems, applicable to a wide range of anticancer agents, may eventually lead to an effective cancer therapy in the future.

• Nuclear Medicine and Molecular Imaging
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• 제40권2호
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• pp.96-105
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• 2006

Molecular imaging has its root in nuclear medicine and gene therapy monitoring. Therefore, recent progress in the development of non-invasive imaging technologies, particularly nuclear medicine, should allow molecular imaging to play a major role in the field of gene therapy. These tools have recently been validated in gene therapy models for continuous quantitative monitoring of the location, magnitude, and time-variation of gene delivery and/or expression. This article reviews the use of radionuclide imaging technologies as they have been used in imaging gene delivery and gene expression for gene therapy applications. The studios published to date lend support that noninvasive imaging tools will help to accelerate pre-clinical model validation as well as allow for clinical monitoring of human gene therapy.

• Journal of Microbiology and Biotechnology
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• 제25권6호
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• pp.788-794
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• 2015

Cationic liposomes have been actively used as gene delivery vehicles despite their unsatisfactory efficiencies because of their relatively low toxicity. In this study, we designed novel heterodimeric peptides as nonviral gene delivery systems from TAT and NLS peptides using cysteine-to-cysteine disulfide bonds between the two. Mixing these heterodimeric peptides with DNA before mixing with lipofectamine resulted in higher transfection efficiencies in MCF-7 breast cancer cells than mixing unmodified TAT, NLS, and a simple mixture of TAT and NLS with DNA, but did not show an adverse effect on cell viability. In gel retardation assays, the DNA binding affinities of heterodimeric peptides were stronger than NLS but weaker than TAT. However, this enhancement was only observed when heterodimeric peptides were premixed with DNA before being mixed with lipofectamine. The described novel transfection-enhancing peptide system produced by the heterodimerization of TAT and NLS peptides followed by simple mixing with DNA, increased the gene transfer efficiency of cationic lipids without enhancing cytotoxicity.

• Bulletin of the Korean Chemical Society
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• 제28권1호
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• pp.63-67
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• 2007

Biodegradable cationic poly(ester-amide) polymers were synthesized by double-monomer method, that showed excellent solubility in many organic solvents and water. Different degradation patterns were obtained by the regulation of monomer ratios and overall long period of time of DNA protection up to 12 days was shown by PicoGreen reagent assay. Good transfection profiles in the presence of serum and very low toxicity on mammalian cells may allow these polymers to become suitable for long-term gene delivery systems and therapeutic applications.