• Oncology Letters
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• 제17권3호
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• pp.2576-2582
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• 2019

Gestational trophoblastic disease (GTD) is an unusual disease occurring in pregnancy that originates from abnormal trophoblastic cells and comprises a group of diseases with different properties of invasion, metastasis and recurrence. The GTD group includes hydatidiform moles and gestational trophoblastic neoplasms (GTNs), with GTNs being divided into invasive moles, choriocarcinoma, placental site trophoblastic tumors and epithelioid trophoblastic tumors. The present review focuses on current effective treatments for GTD, including conventional and novel promising direct enzyme prodrug therapies (DEPTs). Conventional therapies, such as chemotherapy and hysterectomy, are currently used in a clinical setting; however, the use of diverse DEPTs, including antibody-DEPT and gene-DEPT is also being attempted to cure GTNs. In addition, gene delivery tools using genetically engineered neural stem cells (NSCs) are presently being examined for the treatment of GTNs. The tumor-tropism of NSCs by chemoattractant factors is a unique characteristic of these cells and can serve as a vehicle to deliver anticancer agents. Previous studies have demonstrated that injection with NSC-expressing suicide genes into xenograft animal models has a significant inhibitory effect on tumor growth. Stem cells can be genetically engineered to express anticancer genes, which migrate to the metastatic sites and selectively target cancer cells, and are considered to effectively target metastatic GTNs. However, the safety issue of stem cell therapy, such as tumorigenesis, remains a challenge. Novel therapies comprising a combination of conventional and novel promising treatments are anticipated to be definitive treatments for metastasized and/or recurrent patients with GTNs.

• 대한생식의학회:학술대회논문집
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• 대한불임학회 제1차 연수강좌
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• pp.229-234
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• 2000

Transgenic animal technology has provided new opportunities in many aspects of biotechnology and medicine during two decades. Several gene delivery systems including pronuclear injection, retroviral vectors, sperm vectors, and somatic cell cloning have been tried to generate new functional animals. In the future somatic cell cloning technology will be a major method in the transgenic animal production. Many factors enhancing overall transgenic efficiency should be overcome to facilitate the industrial applications of transgenic technology. Transgenic animal technology has settled down in some areas of the medicine, especially the mass production of pharmaceutical proteins and xenotransplantation. Thus, animal biotechnology will contribute to welfare of human being.

• 한국수정란이식학회:학술대회논문집
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• 한국수정란이식학회 2000년도 추계학술대회 및 정기총회
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• pp.64-65
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• 2000

• 한국가축번식학회지
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• 제22권4호
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• pp.419-424
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• 1998

토끼 수정란의 전핵에 MT-hGH 유전자를 주입하고 핵이식 기법으로 형질전환 복제수정란의 생산효율과 PCR 검색으로 복제수정란에서 유전자존재 여부를 조사한 바 다음과 같은 결론을 얻었다. 1. MT-hGH 유전자를 주입하여 8- 및 16- 세포기로 자란 수정란을 공핵란으로 사용하여 핵이식을 실시하였던 바, 세포융합률은 각각 60.0%, 62.8% 로 비슷하였으나 정상수정란을 공급핵으로 사용한 80.4% 보다 유의적으로 낮은 융합률을 보였다. 그러나 이들 복제수정란의 체외발달률은 처리군간에 유의적인 차이는 인정되지 않았다. 2. 유전자 주입 후 8- 및 16- 세포기로 자란 수정란의 할구를 이용하여 핵이식으로 복제하고 체외에서 배반포까지 자란 수정란을 PCR -screening으로 유전자를 검출한 결과, 각각 23% 와 33% 의 유전자 양성 수정란을 감별하였다.

• 한국수정란이식학회지
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• 제17권1호
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• pp.45-53
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• 2002

본 연구는 sperm-mediated gene transfer를 이용하여 ICSI에 의한 형질전환동물 생산의 기초자료로서 활용하기 위해, ICSI에 사용될 정자의 조건과, 그에 따라 적합한 돼지 정자와 외래유전자의 전처리 및 ICSI를 통한 수정을 및 후기 배로의 발달율과 외래유전자의 발현 여부를 조사하여 다음과 같은 결과를 얻었다. ICSI에 이용될 정자의 조건에 따라 정소상체미부정자, 사출정자 및 동결정자를 이용하여 ICSI후 수정율은 각각 72.3%, 64.1% 및 74.1%로 나타나 유의적인 차이를 나타내지 않았으며, 또한 후기배로의 발달율에 있어서도 각각 17.6%, 18.7% 및 15.0%로 나타나 각 처리군간의 유의적인 차이는 나타나지 않았다. 그리고, ICSI후 전기적 자극을 실시한 군과 실시하지 않은 군에서 난자의 활성화에 따른 수정율은 대조구로 이용한 shame injection과 전기적 활성화를 실시하지 않은 군에서 각각 47.1%와 46.3%로 나타나 전기적 활성화를 실시한 군의 79.6%에 비해 유의적인 차이를 나타내었다. 후기배로의 발달율에 있어서도 전기적 활성화를 실시한 군에서는 24.1%로 나타나 전기 적 활성화를 실시하지 않은 군에서의 14.4%와 유의적인 차이를 나타내었다. 그리고 대조구로 이용한 shame injection에 있어서 후기 배로의 발달율은 2.5%로 낮은 결과를 나타내었다. 또한, 정자와 pcDNA LacZ유전자의 처리시 electroporation 방법을 실시하여 ICSI후 난자를 각각 전기적 활성화를 실시한 군과 실시하지 않은 군에 있어서 유전자 발현율은 각각 30.2%와 24.2% 나타났으나, 두 처리군간에 유의적인 차이는 나타나지 않았다. 그러나, 두 군에서 pcDNA LacZ 유전자는 모두 mosaic 발헌 양상을 보였다. 이상의 실험 결과들을 종합해 보면, ICSI에 사용될 수 있는 돼지의 정자는 정소상체미부정자, 사출정자 및 동결정자 모두가 이용 가능하며, ICSI후 추가 전기적 자극에 의한 난자의 활성화가 수정율과 후기 배로의 발달율을 향상시킬 수 있음을 시사하였다. 따라서, 돼지에 있어서 정자의 외래유전자 도입에 대한 정확하고 실용적인 방법은 보고되고 있지는 않은 상태로, 정자와 외래유전자의 처리법을 향상시키기 위하여 다양한 방법으로 많은 연구가 요구된다.

• 한국가축번식학회지
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• 제23권1호
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• pp.13-18
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• 1999

정소내 성숙한 정자를 생산하는 전능성을 가진 정조세포는 체세포와 동일수준으로 외래 유전자를 삽입 가능한 것으로 알려져 있다. 그러나, 이들 세포가 반수체 이후의 단계로 분화한 경우에는 왜래 유전자를 삽입하기보다는 단순히 결합하는 능력이 있는 것으로 알려져 있다 . 따라서, 본 연구는 외래 유전자를 정소실질내 주입함으로써 형질전환 동물생산이 가능한지에 대하여 검토하기 위하여, 한쪽 정소를 거세한 한국 재래산 양을 사용하였다. Liposome /DNA 복합체를 1 : 2의 비율로 희석한 후 정소실실내에 주입하여 정자를 경유한 유전자 전이의 가능성을 확인하였다. 또한 동결보존한 정액을 인공수정하기 위하여 PGF$_2$$\alpha$(0.15mg/kg/BW)를 근육 주사함으로써 인위적으로 발정을 유도한 후, 인공수정을 이용하여 임신과 분만을 유도하였다. 이들 결과를 요약하면 다음과 같다. 1. PCR에 의하여, 유전자 도입 후 채취한 정액에서 외래유전자는 80일 이상 존재하였으며, 가장 높은 전이율은 40 일째 얻어졌다. 이들 결과는 정조세포에 외래 유전자가 성공적으로 삽입되었음을 제안하였다. 2. 23 두 (평균 96 % 의 발정 유기율)의 재래산양에게 인공수정을 실시한 결과 이들 중 4두가 임신되어 7두의 자양이 생산되었다. 3. 생산된 7두의 산자중 genome DNA를 추출하여 PCR 및 Southern blotting을 실시 한 결과 2두가 형질전환으로 확인되었다. 이상의 결과로서 정자를 매개로 한 정소실질내 외래 유전자의 주입법은 형질전환의 생산을 위한 매우 유용한 수단으로 사용 가능함을 제안하였다.

• The Korean Journal of Physiology and Pharmacology
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• 제17권6호
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• pp.505-510
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• 2013

Electroacupuncture (EA) is a modified form of acupuncture that utilizes electrical stimulation. We previously showed that EA stimulated rats were divided into responders that were sensitive to EA and non-responders that were insensitive to EA based on the tail flick latency (TFL) test. The dopamine beta-hydroxylase (DBH) gene was more abundantly expressed in the hypothalamus of responder rats than non-responder rats. To determine whether overexpression of DBH gene expression in the hypothalamus modulate EA analgesia, we constructed a DBH encoding adenovirus and which was then injected into the hypothalamus of SD rats. Microinjection of DBH or control GFP virus into the hypothalamus had no changes on the basal pain threshold measured by a TFL test without EA treatment. However, the analgesic effect of EA was significantly enhanced from seven days after microinjection of the DBH virus, but not after injection of the control GFP virus. DBH expression was significantly higher in the hypothalamus of DBH virus injected rat than control GFP virus or PBS injected rats. Moreover, expression of the DBH gene did not affect the body core temperature, body weight, motor function or learning and memory ability. Although the functional role of DBH in the hypothalamus in the analgesic effect of EA remains unclear, our findings suggest that expression of the DBH gene in the hypothalamus promotes EA analgesia without obvious side-effects.

• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2000년도 국제심포지움
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• pp.7-8
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• 2000

Transgenic animals are very useful for scientific, pharmaceutical, and agricultural purposes. In livestock, transgenic technology has been used forthe genetic alteration of farm animals, the production of human proteins inlarge quantities in the milk of transgenic farm animals, and the generation of animals with organs suitable for xenotransplantation. To date, the transfer of foreign genes into farm animals has been performed mainly by microinjection of DNA into the pronuclei of fertilized eggs. However, the overall success rate of transgenic animals in livestock so far has been disappointingly low, eg., the efficiency is 0∼5% in swine, and less than 1% in sheep and cattle, compared with the rate in mice where 5% microinjected develop into transgenic animals. Recently, McGreath et al. (2000) have succeeded in producing the gene targeted sheep by the use of nuclear transfer from cultured somatic cells transfected with a foreign gene in vitro. However, we may need plenty of time until currently employ this method for gene transfer to farm animals. We have been studying to exploit the method for improving production efficiencies of transgenic animals with emphasis of its application to farm animals. The present paper describes three approaches that we have made in our laboratory to improve production efficiencies of transgenic animals, based on the DNA microinjection method. 1. Co-injection of restriction enzyme with foreign DNA into the pronucleus for elevating production efficiencies of transgenic animals. 2. Efficient selection of transgenic mouse embryos using EGFP as a marker gene. 3. Phenotypes of tansgenic mice expressing WAP/hGH-CAG/EGFP fusion gene produced by selecting transgenic embryos. 4. Efficient site-specific integration of the transgene targeting an endogenous lox like site in early mouse embryos.

• 한국수정란이식학회지
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• 제15권2호
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• pp.167-173
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• 2000

The principal objective of this study was to clone transgenic embryos in order to improve the efficiency of transgenic animal production by the combination of microinjection and nuclear transplantation techniques. Mature female New Zealand White rabbits were superovulated by eCG and hCG treatments, fllowed by natural mating. Zygotes were collected from the oviducts at 18∼22 h after hCG injection by flushing with D-PBS containing 5% fetal calf serum(FCS). Two to three picoliters of green fluorescent protein(GFP) gene wa microinjected into male pronucleus. The foreign gene-injected zygotes were cultured in TCM-199 or RD medium containing 10% FCS with a monolayer of rabbit oviductal epithelial cells in a 5% CO2 incubator. The morulae expressing GFP gene were selected and their blastomeres were separated for the use of nuclear donor. Following nuclear transplantation of fluorescence-positive morula stage blastomeres, 13 (21.3%) out of 61 fused oocytes developed to blastocyst stage and all of the cloned blastocysts expressed GFP. The results indicate that the screening of transgene in rabbit embryos by GFP detection could be a promisible method for the preselection of transgenic embryos. Also the cloning of preselected transgenic embryos by nuclear transplantatin could be efficiently applied to the multiple production of transgenic animals.

• Asian-Australasian Journal of Animal Sciences
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• 제14권2호
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• pp.163-169
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• 2001

Despite the high potency of the retrovirus vector system in gene transfer, one of the main drawbacks of has been difficulty in preparing highly concentrated virus stock. Numerous efforts to boost the virus titer have ended in unsatisfactory results mainly due to fragile property of retrovirus envelope protein. In this study, to overcome this problem, we constructed our own retrovirus vector system producing vector viruses encapsulated with VSV-G (vesicular stomatitis virus G glycoprotein). Concentration process of the virus stock by ultracentrifuge did not sacrifice the virus infectivity, resulting in more than 108 to 109 CFU (colony forming unit) per ml on most of the target cell lines tested. Application of this high-titer retrovirus vector system was tested on chicken embryos. Injection of virus stock beneath the blastoderms of pre-incubated fertilized eggs resulted in chick embryos expressing E. coli LacZ gene with 100% efficiency. Therefore, our results suggest that it is possible to transfer the foreign gene into chicken embryo using our high-titer retrovirus vector.