• 생명과학회지
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• 제13권1호
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• pp.118-127
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• 2003

Phenylalanine의 구조유사체인 p-fluotophenylalanine (FPA)은 인체 급성백혈병세포주인 Jurkat T 세포의 세포자살을 유도한다. FPA에 의한 세포자살에 미치는 Bcl-2 또는 Bcl-xL의 영향을 조사하기 위해, Bcl-2 또는 Bcl-xL을 stable transfection하거나 empty vectors만을 Transfection한 Jurkat 세포를 이용하여 FPA의 세포독성과 FPA에 의한 세포내 세포자살 신호전달경로를 비교 분석하였다. Jurkt T 세포에 0.63∼3.0 mLf의 FPA를 처리하였을 때 세포의 생육도는 농도에 비례하여 감소하였다. 또한 세포자살관련 DNA fragmentation, caspase-8 activatoin, Bid cleavage, mitochondria로 부터의 cytochrome c 방출, caspase-9 및 -3 activation, PARP degradation 등이 유도되었다. 한편, FPA에 의해 유도되는 이러한 일련의 생화학적 현상들은 Bcl-2 또는 Bcl-xL의 overexpression에 의해 현저히 저해되었다. 이상의 결과들은 caspase-8 activation, Bid cleavage, mitochondnal cytochrome c 방출에 의해 활성화되는 casuase cascade 등의 현상이, Bcl-2 또는 Bcl-xL에 의해 억제됨을 나타내며 FPA에 의해 유도되는 세포자살에 필요한 과정임을 시사한다.

• Clinical and Experimental Pediatrics
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• 제48권5호
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• pp.495-499
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• 2005

목 적 : IL-4는 Th2 면역 반응의 중요한 매개체로 IL4 유전자의 promoter 일배체형(haplotype)은 한국인 소아에서 RSV에 의한 심한 모세기관지염과 연관된다고 알려져 있다. 본 연구는 IL4 유전자의 promoter 다형성에 따른 IL-4 단백의 기능적인 변화를 분석하여 심한 RSV 하기도 감염증에 기여하는 IL4 유전자의 발병 기전의 연관성을 연구하고자 시행하였다. 방 법 : 면역 기능이 정상인 소아 20명을 대상으로 전혈을 채취한 후 genomic DNA를 추출하여 IL4 유전자 promoter 약 1.2 kb 부위를 증폭시켰다. 염기서열 분석을 통하여 IL4 유전자 promoter의 유전형을 결정하고, PHASE 분석으로 일배체형을 결정하였다. 각 일배체형별로 $5{\mu}g$의 DNA를 Jurkat T 세포에 핵형질변환 시켜서 정상 Jurkat T 세포와 PMA(50 ng/mL)로 자극한 세포에서의 luciferase 활성도를 분석하여 IL4 유전자 promoter의 전사능을 결정하였다. 결 과 : 한국인 소아의 일배체형은 3가지 유형 GCC(7%), TCC(17%), 및 TTT(76%)로 분포하였다. Jurkat T 세포의 절대 luciferase 활성도는 GCC형이 가장 낮았고 TTT형이 가장 높았다. GCC 일배체형을 기준으로 하여 나타낸 Jurkat T 세포의 상대 luciferase 활성도는 TCC형이 4.2배, TTT형이 5.3배로 증가되었다. PMA로 자극한 후에 측정한 각 일배체형의 luciferase 활성도 역시 GCC형에 비하여 TCC형이 3.0배, TTT형이 4.1배로 증가되어 자극하지 않은 세포에서와 유사한 활성도의 차이를 보였다. 결 론 : 소아의 심한 RSV 하기도 감염증과 연관된 IL4 유전자의 promoter 일배체형 TTT는 IL4 유전자의 promoter의 전사능을 증가시킴으로써 영아 및 소아의 RSV 하기도 감염증의 병인에 중요한 역할을 할 것으로 생각된다.

• Molecules and Cells
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• 제37권5호
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• pp.426-434
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• 2014

Peptidylarginine deiminase type 2 (PADI2) deiminates (or citrullinates) arginine residues in protein to citrulline residues in a $Ca^{2+}$-dependent manner, and is found in lymphocytes and macrophages. Vimentin is an intermediate filament protein and a well-known substrate of PADI2. Citrullinated vimentin is found in ionomycin-induced macrophage apoptosis. Citrullinated vimentin is the target of anti-Sa antibodies, which are specific to rheumatoid arthritis, and play a critical role in the pathogenesis of the disease. To investigate the role of PADI2 in apoptosis, we generated a Jurkat cell line that overexpressed the PADI2 transgene from a tetracycline-inducible promoter, and used a combination of 12-O-tetradecanoylphorbol-13-acetate and ionomycin to activate Jurkat cells. We found that PADI2 overexpression reduced the cell viability of activated Jurkat cells in1a dose- and time-dependent manner. The PADI2-overexpressed and -activated Jurkat cells presented typical manifestations of apoptosis, and exhibited greater levels of citrullinated proteins, including citrullinated vimentin. Vimentin overexpression rescued a portion of the cells from apoptosis. In conclusion, PADI2 overexpression induces apoptosis in activated Jurkat cells. Vimentin is involved in PADI2-induced apoptosis. Moreover, PADI2-overexpressed Jurkat cells secreted greater levels of vimentin after activation, and expressed more vimentin on their cell surfaces when undergoing apoptosis. Through artificially highlighting PADI2 and vimentin, we demonstrated that PADI2 and vimentin participate in the apoptotic mechanisms of activated T lymphocytes. The secretion and surface expression of vimentin are possible ways of autoantigen presentation to the immune system.

• Biomolecules & Therapeutics
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• 제18권3호
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• pp.262-270
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• 2010

CD95 receptor is a member of tumor necrosis factor receptor family that mediates apoptosis in many cell types when bound by CD95 ligand or cross-linked by agonistic anti-CD95 antibodies. To determine the role of neutral sphingomyelinase (nSMase) on CD95-mediatd apoptosis, human Jurkat T lymphocytes were exposed to recombinant human CD95 ligand. Treatment with CD95 ligand induced cell death in a concentration and time-dependent manner. CD95-induced cell death was suppressed by inhibitors of SMase such as AY9944 or desipramine. Transfection with human nSMase1 siRNA plasmid into CD95 ligand-treated cells significantly prevented CD95-mediated cell death. CD95-mediated elevation of intracellular ceramide level detected by FACS analysis with anti-ceramide antibody was also decreased by nSMase1 siRNA. Knock-down of nSMase1 expression also blocked cytochrome c release into cytosol and caspase-3 cleavage in CD95-treated cells. Taken together, these results suggest that nSMase1 may play an important role in CD95-mediated apoptotic cell death in Jurkat T cells.

• 약학회지
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• 제48권2호
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• pp.153-158
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• 2004

Paecilomyces tenuipes is one of the famous Chinese medicinal entomopathogenic fungi that parasite in the lavae of silkworm. A cytotoxic compound, 4$\beta$-acetoxyscirpendiol (ASD) was isolated from a methanolic extracts of Paecilomyces tenuipes. The ASD compound belongs to scirpenol subfamily of trichothecene mycotoxin. In a continuation of the elucidation of the mechanism of ASD, we report here the evidences of induction of apoptosis by ASD in human Jurkat T cell line. In MTT reduction assay for monitoring cell viability, ASD showed strong toxicity. The 50 percent inhibitory concentrations of ASD against human T lymphoid Jurkat cell was 59.5 ng/$m\ell$. Phosphatidylserine externalization was increased by ASD at 3 and 6 hrs when compared with that of 6 hrs in the cell line showing in a time-dependent manner. When whole lysates of cells treated with ASD were subjected to western blot assay, 113 kDa poly(ADP-ribose) polymerase (PARP) was significantly cleaved to 89 kDa fragment. Time-dependent DNA fragmentation was also observed when Jurkat T cells were treated with ASD at 100 ng/$m\ell$ for 6 hrs and 18 hrs at the ratios of 8.5% and 15.0%, respectively. From these data, Jurkat T lymphocytes treated with ASD from Paecilomyces tenuipes underwent typical cascades of apoptotic cell death.

• 생명과학회지
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• 제11권1호
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• pp.8-18
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• 2001

The purpose of this study was to evaluate the genotypic characterization of Actinobacillus actinomycetemcomitans (A. actinomycetemcomitans) using arbitrarily primed polymerase chain reaction (AP-PCR), to investigate the cytotoxicity of both clinical isolates and standard strains of A. actinomycetemcomitans for the human Jurkat T cells, and to measure the osteoclastogenic cytokines released by Jurkat cells infected with these bacterial strains. The random sequence primer 15 and 16 could distinguish different AP-PCR profiles between clinical isolates of A. actinomycetemcomitans. A. actinomycetemcomitans significantly suppressed Jurkat cell viability in time dependent fashion and the results of DNA fragmentation assay indicated that this bacterial species induced apoptosis in Jurkat cells undergoing apoptosis released the osteoclastogenic cytokine, IL-1$\beta$, IL-6, TNF-$\alpha$. These data support the hypothesis that induction of apoptosis is at least one essential step in A. actinomycetemcomitans induced local immunosuppressive pathway, and that A. actinomycetemcomitans can modulate the immunomodulatory cell population in the periodontal tissue by inducing T cell death through apoptosis, and that apoptosis of local resident T cells may play an active role in bone resorption by releasing osteoclastogenic cytokines, e.g. IL-1$\beta$, IL-6, TNF-$\alpha$.

• IMMUNE NETWORK
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• 제6권2호
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• pp.67-75
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• 2006

Background: Cytotoxic function of killer cells is inhibited by specific recognition of class I MHC molecules on target cells by inhibitory killer Ig-like receptors (KIR) expressed on NK cells and some cytotoxic T cells. The inhibitory effect of KIR is accomplished by recruitment of SH2-containing protein tyrosine phosphatase (SHP) to the phosphotyrosine residues in the cytoplasmic tail. Methods: By in vitro coprecipitation experiments and transfection analysis, we investigated the association of KIR with an adaptor protein Shc in Jurkat T cells. Results: The cytoplasmic tail of KIR appeared to associate with an adaptor protein Shc in Jurkat T celilysates. Similar in vitro experiments showed that phosphorylated KIR cytoplasmic tail bound SHP-1 and Shc in Jurkat T cell lysates. The association of KIR with Shc was further confirmed by transfection analysis in 293T cells. Interestingly, however, Shc appeared to be replaced by SHP-2 upon engagement of KIR in 293T cells. Conclusion: Our data indicate that KIR associate with an adaptor protein Shc in Jurkat T cells, and suggest that KIR might have an additional role which is mediated by this adaptor protein.

• Parasites, Hosts and Diseases
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• 제59권5호
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• pp.501-505
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• 2021

The pathogenic free-living amoeba Naegleria fowleri causes primary amoebic meningoencephalitis, a fatal infection, by penetrating the nasal mucosa and migrating to the brain via the olfactory nerves. N. fowleri can induce host cell death via lytic necrosis. Similar to phosphorylation, O-linked β-N-acetylglucosamine (O-GlcNAc) glycosylation (O-GlcNAcylation) is involved in various cell-signaling processes, including apoptosis and proliferation, with O-GlcNAc addition and removal regulated by O-GlcNAc transferase and O-GlcNAcase (OGA), respectively. However, the detailed mechanism of host cell death induced by N. fowleri is unknown. In this study, we investigated whether N. fowleri can induce the modulation of O-GlcNAcylated proteins during cell death in Jurkat T cells. Co-incubation with live N. fowleri trophozoites increased DNA fragmentation. In addition, incubation with N. fowleri induced a dramatic reduction in O-GlcNAcylated protein levels in 30 min. Moreover, pretreatment of Jurkat T cells with the OGA inhibitor PUGNAc prevented N. fowleri-induced O-deGlcNAcylation and DNA fragmentation. These results suggest that O-deGlcNAcylation is an important signaling process that occurs during Jurkat T cell death induced by N. fowleri.

• 대한의생명과학회지
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• 제29권4호
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• pp.376-381
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• 2023

Abscopal effect is a form of secondary immune response that occurs in ionizing radiation therapy, resulting in changes in the immune response through activation of immune cells such as macrophages and T lymphocytes. UVB causes DNA damage similar to ionizing radiation and causes similar intracellular reactions, so it is often used as an alternative in research on the effects of ionizing radiation. In a previous study, we found that pro-inflammatory cytokines, including TNF-α, increased in Jurkat T cells exposed to TGs. In this study, we confirmed the effects of UVB irradiation on T lymphocytes exposed to TGs, similar to the effects of ionizing radiation. As a result, it was shown that the mRNA expression of pro-inflammatory cytokines such as IL-1β and IFN-γ in Jurkat T cells exposed to TGs increased by UVB irradiation. In addition, it was confirmed that the increase in the expression of pro-inflammatory cytokines caused by UVB was caused by the activation of iNOS protein. This is very similar to the immune response that occurs when T lymphocytes are exposed to TGs. These results suggest that activation of iNOS protein is involved in the increase in pro-inflammatory cytokines caused by UVB irradiation in T lymphocytes exposed to TGs.

• 대한임상검사과학회지
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• 제47권4호
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• pp.182-187
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• 2015

야생 생강 Zingiber zerumbet Smith의 정유에 포함되어 있는 주요 성분인 zerumbone은 면역세포를 포함한 여러 종류의 세포기능에 영향을 미치는 것으로 알려져 있다. 또한, 종양, 염증을 포함한 여러 생물학적 환경에서 기능을 나타냄이 보고되었다. 본 연구에서는 zerumbone이 SDF-$1{\alpha}$로 유도된 T림프구 세포주 Jurkat 세포의 이동을 감소시키는 것을 transwell system을 이용하여 확인하였다; 100 ng/mL의 SDF-$1{\alpha}$로 유발시킨 이동은 약 25%, 200 ng/mL의 SDF-$1{\alpha}$로 유발시킨 경우에는 약 17%의 감소를 나타냈다. 반면에, Jurkat 세포의 기본 증식에는 큰 변화를 유발하지 않는다는 점을 WST assay를 통해 확인하였다. 이는 zerumbone이 지닌 새로운 기능이지만, 향후 생리적 세포를 통해 다시 확인해야 하며, zerumbone에 의한 세포자멸사 유발, CXCR4 발현 감소 등 세포학적 기전 연구와 ZAP-70, Erk1/2의 인산화 변화 측정 등 생화학적 기전 연구가 필요하다.