• IMMUNE NETWORK
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• 제11권5호
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• pp.268-280
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• 2011

Background: Dengue virus, which belongs to the Flavivirus genus of the Flaviviridae family, causes fatal dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS) with infection risk of 2.5 billion people worldwide. However, approved vaccines are still not available. Here, we explored the immune responses induced by alternating prime-boost vaccination using DNA vaccine, adenovirus, and vaccinia virus expressing E protein of dengue virus type 2 (DenV2). Methods: Following immunization with DNA vaccine (pDE), adenovirus (rAd-E), and/or vaccinia virus (VV-E) expressing E protein, E protein-specific IgG and its isotypes were determined by conventional ELISA. Intracellular CD154 and cytokine staining was used for enumerating CD4+ T cells specific for E protein. E protein-specific CD8+ T cell responses were evaluated by in vivo CTL killing activity and intracellular IFN-${\gamma}$ staining. Results: Among three constructs, VV-E induced the most potent IgG responses, Th1-type cytokine production by stimulated CD4+ T cells, and the CD8+ T cell response. Furthermore, when the three constructs were used for alternating prime-boost vaccination, the results revealed a different pattern of CD4+ and CD8+ T cell responses. i) Priming with VV-E induced higher E-specific IgG level but it was decreased rapidly. ii) Strong CD8+ T cell responses specific for E protein were induced when VV-E was used for the priming step, and such CD8+ T cell responses were significantly boosted with pDE. iii) Priming with rAd-E induced stronger CD4+ T cell responses which subsequently boosted with pDE to a greater extent than VV-E and rAd-E. Conclusion: These results indicate that priming with live viral vector vaccines could induce different patterns of E protein-specific CD4+ and CD8+ T cell responses which were significantly enhanced by booster vaccination with the DNA vaccine. Therefore, our observation will provide valuable information for the establishment of optimal prime-boost vaccination against DenV.

• 대한임상약리학회:학술대회논문집
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• 대한임상약리학회 2006년도 제15차 추계학술대회
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• pp.29-30
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• 2006

• Journal of Microbiology and Biotechnology
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• 제29권4호
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• pp.651-657
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• 2019

Although smallpox was eradicated in 1980, it is still considered a potential agent of biowarfare and bioterrorism. Smallpox has the potential for high mortality rates along with a major public health impact, eventually causing public panic and social disruption. Passive administration of neutralizing monoclonal antibodies (mAbs) is an effective intervention for various adverse reactions caused by vaccination and the unpredictable nature of emerging and bioterrorist-related infections. Currently, vaccinia immune globulin (VIG) is manufactured from vaccinia vaccine-boosted plasma; however, this production method is not ideal because of its limited availability, low specific activity, and risk of contamination with blood-borne infectious agents. To overcome the limitations of VIG production from human plasma, we isolated two human single-chain variable fragments (scFvs), (SC34 and SC212), bound to vaccinia virus (VACV), from a scFv phage library constructed from the B cells of VACV vaccine-boosted volunteers. The scFvs were converted to human IgG1 (VC34 and VC212). These two anti-VACV mAbs were produced in Chinese Hamster Ovary (CHO) DG44 cells. The binding affinities of VC34 and VC212 were estimated by competition ELISA to $IC_{50}$ values of $2{\mu}g/ml$ (13.33 nM) and $22{\mu}g/ml$ (146.67 nM), respectively. Only the VC212 mAb was proven to neutralize the VACV, as evidenced by the plaque reduction neutralization test (PRNT) result with a $PRNT_{50}$ of ~0.16 mg/ml (${\sim}1.07{\mu}M$). This VC212 could serve as a valuable starting material for further development of VACV-neutralizing human immunoglobulin for a prophylactic measure against post-vaccination complications and for post-exposure treatment against smallpox.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1994년도 춘계학술대회 and 제3회 신약개발 연구발표회
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• pp.153-163
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• 1994

P450s are a superfamily of heme-containing monooxygenases and important in the metabolism of numerous physiological substrates and foreign compounds. It has been established that tilers are at least 30 distinct human isoforms of P450. Four families containing numerous individual P450s are mainly responsible for metabolizing foreign compounds, A cDNA expression system in which individual human P450s are synthesized in cultured human hepatoma (Hep G2) cells infected with a recombinant vaccinia virus containing human P450 cDNA has been constructed.

• BMB Reports
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• 제28권3호
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• pp.243-248
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• 1995

Cholesteryl ester transfer protein (CETP), a hydrophobic glycoprotein promoting transfer of cholesteryl esters (CE) from high-density lipoproteins (HDL) to lower-density lipoproteins in the plasma, has been recognized a potent atherogenic factor during the development of coronary artery diseases. This study demonstrated a possible utilization of antisense RNA to inhibit expression of the CETP gene using vaccinia virus as an expression system. The CETP cDNA was inserted into a transfer vector (pSC11) in sense and antisense orientations and used to generate recombinant viruses. Recombinants containing sense or antisense orientations of the CETP cDNA were isolated by $TK^-$ selection and X-gal test. The inserted CETP cDNAs in the recombinants were identified by Southern blot analysis and allowed to transcribe in host cells (CV-1). Expressions of the exogenous CETP mRNA, extracted from the CV-1 cells coinfected with viruses containing sense and antisense DNAs, were monitored by Northern blot analysis using the CETP cDNA probe, by Western blot analysis using monoclonal antibody against the C-terminal active region of the CETP and by the CETP assay. Decreased expressions of the exogenous CETP cDNA were clearly evident in the Northern and Western blot analyses as the dose of antisense expression increased. In the CETP assay, the CETP activities decreased compared to the activity obtained from the cell extracts infected with sense construct only.

• KSBB Journal
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• 제13권1호
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• pp.83-89
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• 1998

Cellulose로 만들어진 다공성 미립담체를 이용하여 HeLa cell을 working volume 100mL의 spinner flask에서 배양하였으며, 세포가 완전히 자란 미립담제를 계대배양하기 위하여 담체간 세포 전이 배양 방법을 시도하였다. 부유세포의 농도는 다공성 미립담체-HeLa 시스템의 경우에 담체간 세포 전이 배양에 영향을 미치는 중요한 인자로 작용하였으며, 낮은 칼슘농도의 배지인 RPMI-1640과 빠른 교반 속도를 이용하여 활성을 유지한 많은 세포가 떨어지도록 유도하였으며, 담체간 세포 전이 배양을 효과적으로 3회 이상 실시할 수 있었다. 이렇게 배양한 세포에 재 조합 Vaccinia virus를 감염하여 그 수율을 비교한 결과 T-flask에서 떼어낸 세포로 접종한 미립담체 배양과 거의 비슷한 재조합 단백질($\beta$-galactosidase) 수율을 나타내었다. Trypsin 처리 방법에 의한 미립담체 계대 배양도 경우에 따라서는 유용한 미립담체 계대 배양 방법이 될 수 있지만 실제 생산 규모에의 적용에는 공정이 복잡해지고 정확한 제어가 필요하다는 등의 문제가 있다. 따라서, 추가적인 비용이나 공정이 필요 없는 간편한 방법인 담체간 세포 전이 배양은 동물세포 배양을 이용한 유용 단백질 및 바이러스 생산 공정의 규모 증대에 매우 유용한 수단이다.

• 생명과학회지
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• 제26권7호
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• pp.835-846
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• 2016

항암제 내성은 화학적 치료법의 가장 큰 난관의 하나로 효과적인 항암치료를 위해서 반드시 극복 되야 할 문제이다. ABCG2는 다약제 내성과 이를 특징으로 하는 암 줄기세포와의 연관성도 매우 높다고 보고되고 있다. 최근 암용해 바이러스가 다양한 암종과 항암제내성을 보이는 암 치료에 새로운 대안으로 대두되고 있다. 이에 본 연구에서는 항암제 내성 암 치료를 위해 새로운 암용해 백시니아 바이러스 SLJ-496을 개발하였다. 본 연구에서, cytophathic effect, plaque assay, viability assay를 통하여 야생형 바이러스에 비교하여 증가된 종양친화성을 확인하였다. 또한, invitro 환경에서 대장암 세포주(HT-29, HCT-116, HCT-8)를 비롯하여 위암 세포주(AGS, NCI-N87, MKN-28), 간암 세포주(SNU-449, SNU-423, SNU-475, HepG2) 그리고 난치성 암 종인 중피 세포종(NCI-H226, NCI-H28, MSTO-211h)에서 유의적인 세포독성효능을 입증하였다. ABCG2의 발현이 높은 HT-29세포의 3차원 구형배양을 통하여 ABCG2와 암줄기세포 특성의 연관성을 증명하였으며, 항암제 내성세포 모델에서 SLJ-496GFP가 유의한 세포독성을 나타내며 암세포내 복제능을 가지는 것을 입증하였다. ABCG2를 과발현 시킨 세포주 내 야생형 바이러스에 비교하여 유의적으로 낮은 세포 생존율을 증명하였으며, 바이러스의 복제능 또한 검증하였다. 또한, 지속적인 항암제 투여를 통하여 ABCG2의 발현이 높은 항암제 내성 세포주에서의 항종양 효능 또한 입증하였다. 이상의 결과를 토대로 ABCG2가 과발현 된 암 줄기세포 및 항암제 내성에 새로운 항종양 바이러스 SLJ-496 백시니아 바이러스 치료법이 새로운 치료 대안이 될 수 있을 것이라 제안한다.

• Journal of Microbiology and Biotechnology
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• 제28권6호
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• pp.1022-1029
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• 2018

Tuberculosis (TB) remains a serious health issue around the word. Adenovirus (Ad)-based vaccine and modified vaccinia virus Ankara (MVA)-based vaccine have emerged as two of the most promising immunization candidates over the past few years. However, the performance of the homologous and heterologous prime-boost immunization regimens of these two viral vector-based vaccines remains unclear. In the present study, we constructed recombinant Ad and MVA expressing an Ag85B-TB10.4 fusion protein (AdH4 and MVAH4) and evaluated the impact of their different immunization regimens on the humoral and cellular immune responses. We found that the viral vector-based vaccines could generate significantly higher levels of antigen-specific antibodies, $IFN-{\gamma}$-producing splenocytes, $CD69^+CD8^+$ T cells, and $IFN-{\gamma}$ secretion when compared with bacillus Calmette-$Gu{\acute{e}}rin$ (BCG) in a mouse model. AdH4-containing immunization regimens (AdH4-AdH4, AdH4-MVAH4, and MVAH4-AdH4) induced significantly stronger antibody responses, much more $IFN-{\gamma}$-producing splenocytes and $CD69^+CD8^+$ T cells, and higher levels of $IFN-{\gamma}$ secretion when compared with the MVAH4-MVAH4 immunization regimen. The number of $IFN-{\gamma}$-producing splenocytes sensitive to $CD8^+$ T-cell restricted peptides of Ag85B (9-1p and 9-2p) and Th1-related cytokines ($IFN-{\gamma}$ and $TNF-{\alpha}$) in the AdH4-MVAH4 heterologous prime-boost regimen immunization group was significantly higher than that in the other viral vector-based vaccine- and BCG-immunized groups, respectively. These results indicate that an immunization regimen involving AdH4 may have a higher capacity to induce humoral and cellular immune responses against TB in mice than that by regimens containing BCG or MVAH4 alone, and the AdH4-MVAH4 prime-boost regimen may generate an ideal protective effect.

• IMMUNE NETWORK
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• 제12권3호
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• pp.118-125
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• 2012

CD40-CD40L-mediated help from CD4 T cells is essential to induce primary CD8 T cell responses specific to the non-inflammatory cell-based antigen H60. In this study, using H60 as a model antigen, we generated recombinant vaccinia viruses (rVVs) expressing the H60 CD8 epitope and investigated whether CD4 help was required to activate the CD8 T cell response specific to the virally expressed H60. The immune response after infection with rVVs expressing H60 was similar to that after immunization with H60 congenic splenocytes, with a peak frequency of H60-specific CD8 T cells detected in the blood on day 10 post-infection. A CD8 T cell response specific for virally derived H60 was not induced in CD4-depleted mice, but was in CD40-deficient mice. These results provide insights into the characterization of the CD8 T cell response specifically for antigens originating from cellular sources compared to viral sources.

• 대한수의학회지
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• 제39권4호
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• pp.772-777
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• 1999

The uncaped genomic RNA of bovine viral diarrhea virus (BVDV) initiates translation by recruitment of eukaryotic translation initiation factors at the internal ribosome entry site (IRES). N-terminal protease ($N^{pro}$) is the first translation product of the open reading frame (ORF). By using the vaccinia virus SP6 RNA polymerase transient expression system, we showed previously that deletion of $N^{pro}$ region reduced translation by 21%. To better understand the biological significance of $N^{pro}$ for translation, we carried out a mutational analysis of the $N^{pro}$ region of BVDV cloned in the intercistronic region of a bicistronic reporter plasmid. We constructed a bicistronic expression vector in which the entire 5 UTR and the mutated $N^{pro}$ region (${\Delta}386-901$, ${\Delta}415-901$ and ${\Delta}657-901$) was cloned between two reporter genes, chloramphenicol acetyltransferase (CAT) and luciferase (LUC). In vivo translation analyses showed that $N^{pro}$ region was dispensible for efficient translation. The results indicate that the $N^{pro}$ region is not essential for BVDV RNA translation and the 3' boundary of BVDV IRES is expanded into $N^{pro}$ region, suggesting that $N^{pro}$ may not play a major role in BVDV replication.