• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2008년도 International Meeting of the Microbiological Society of Korea
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• pp.62-64
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• 2008

A major hurdle to the development of RNA interference as therapy for HIV infection is the delivery of siRNA to T lymphocytes which are difficult cells to transfect even in vitro. We have employed a single chain antibody to the pan T cell surface antigen CD7 was conjugated to an oligo-9-arginine peptide (scFvCD7-9R) for T cell-specific siRNA delivery in NOD/SCIDIL2${\gamma}$-/- mice reconstituted with human peripheral blood lymphocytes (Hu-PBL). Using a novel delivery, we first show that scFvCD7-9R efficiently delivered CD4 siRNA into human T cells in vitro. In vivo administration to Hu-PBL mice resulted in reduced levels of surface CD4 expression on T cells. Mice infected with HIV-1 and treated on a weekly basis with scFvCD7-9R-siRNA complexes targeting a combination of viral genes and the host coreceptor molecule CCR5 successfully maintained CD4/CD3 T cell ratios up to 4 weeks after infection in contrast to control mice that displayed a marked reduction in CD4 T cell numbers. p24 antigen levels were undetectable in 3 of the 4 protected mice. scFvCD7-9R/antiviral siRNA treatment also helped maintain CD4 T cell numbers with reduced plasma viral loads in Hu-PBL mice reconstituted with PBMC from donors seropositive for HIV, indicating that this method can contain viral replication even in established HIV infections. Our results show that scFvCD7-9R could be further developed as a potential therapeutic for HIV-1 infection.

• Biomolecules & Therapeutics
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• 제24권3호
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• pp.244-251
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• 2016

Understanding the developmental mechanisms of humoral immunity against intranasal antigens is essential for the development of therapeutic approaches against air-borne pathogens as well as allergen-induced pulmonary inflammation. Follicular helper T (Tfh) cells expressing CXCR5 are required for humoral immunity by providing IL-21 and ICOS costimulation to activated B cells. However, the regulation of Tfh cell responses against intranasal antigens remains unclear. Here, we found that the generation of Tfh cells and germinal center B cells in the bronchial lymph node against intranasal proteinase antigens was independent of $TGF-{\beta}$. In contrast, administration of STAT3 inhibitor STA-21 suppressed the generation of Tfh cells and germinal center B cells. Compared with wild-type OT-II T cells, STAT3-deficient OT-II T cells transferred into recipients lacking T cells not only showed significantly reduced frequency Tfh cells, but also induced diminished IgG as well as IgE specific for the intranasal antigens. Cotransfer study of wild-type OT-II and STAT3-deficient OT-II T cells revealed that the latter failed to differentiate into Tfh cells. These findings demonstrate that T cell-intrinsic STAT3 is required for the generation of Tfh cells to intranasal antigens and that targeting STAT3 might be an effective approach to ameliorate antibody-mediated pathology in the lung.

• 대한두경부종양학회:학술대회논문집
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• 대한두경부종양학회 1991년도 제8차 학술대회 연제순서 및 초록집
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• pp.22.2-24
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• 1991

• Asian Pacific Journal of Cancer Prevention
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• 제14권2호
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• pp.631-637
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• 2013

Luteolin is a naturally occurring flavonoid present in many plants with diverse applications in pharmacology. Despite several studies elucidating its significant anti-cancer activity against various cancer cells, the mechanism of action in skin cancer is not well addressed. Hence, we investigated the effects of luteolin in HaCaT (human immortalized keratinocytes) and A375 (human melanoma) cells. The radical scavenging abilities of luteolin were determined spectrophotometrically, prior to a cytotoxic study (XTT assay). Inhibitory effects were assessed by colony formation assay. Further, the capability of luteolin to induce cell cycle arrest and apoptosis were demonstrated by flow cytometry and cellular DNA fragmentation ELISA, respectively. The results revealed that luteolin possesses considerable cytotoxicity against both HaCaT and A375 cells with $IC_{50}$ values of 37.1 ${\mu}M$ and 115.1 ${\mu}M$, respectively. Luteolin also inhibited colony formation and induced apoptosis in a dose and time-dependent manner by disturbing cellular integrity as evident from morphological evaluation by Wright-Giemsa staining. Accumulation of cells in G2/M (0.83-8.14%) phase for HaCaT cells and G0/G1 (60.4-72.6%) phase for A375 cells after 24 h treatment indicated cell cycle arresting potential of this flavonoid. These data suggest that luteolin inhibits cell proliferation and promotes cell cycle arrest and apoptosis in skin cancer cells with possible involvement of programmed cell death, providing a substantial basis for it to be developed into a potent chemopreventive template for skin cancer.

• 대한의생명과학회지
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• 제20권3호
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• pp.162-167
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• 2014

Tuberculosis (TB) is one of the major global health problems and it has been estimated that in 5~10% of Mycobacterium tuberculosis (MTB)-infected individuals, the infection progresses to an active disease. Numerous cytokines and chemokines regulate immunological responses at cellular level including stimulation and recruitment of wide range of cells in immunity and inflammation. In the present study, the mRNA expression levels of eight host immune markers containing of IFN-${\gamma}$, TNF-${\alpha}$, IL-2R, IL-4, IL-10, CXCL9, CXCL10, and CXCL11 in whole blood cells from active pulmonary TB patients were measured after T-cell mitogen (PHA) and MTB specific antigens (ESAT-6, CFP-10, and TB7.7). Among the TH1-type factors, IFN-${\gamma}$ mRNA expression was peaked at 4 h, TNF-${\alpha}$ and IL-2R mRNA expression was significantly high at the late time points (24 h) in active TB patients, TH2-type cytokine (IL4 and IL10) mRNA expression levels in both active TB and healthy controls samples did not changed significantly, and the mRNA expression of the three IFN-${\gamma}$-induced chemokines (CXCL9, CXCL10, and CXCL11) were peaked at the late time points (24 h) in active TB patients after MTB specific antigen stimulation. In conclusion, the mRNA expression patterns of the TB-related immune markers in response to the T-cell mitogen (PHA) differed from those in response to MTB specific antigens and these findings may helpful for understanding the relationship between MTB infection and host immune markers in a transcripts level.

• Natural Product Sciences
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• 제2권2호
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• pp.123-129
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• 1996

Chemical carcinogenesis is associated with the increase of intracellular polyamine levels, and 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced mouse epidermal ODC activity are essential to skin tumor promotion by TPA. Therefore, for the discovery of new cancer chemopreventive agents, we have evaluated about 73 kinds of natural products to study inhibitory effects against ODC activity induced by TPA in T24 cell culture system. The total methanol extracts of plants fractionated into three layers (hexane, ethyl acetate and water layer) were tested and the hexane fraction of Angelica gigas $(root\;bark,\;IC_{50}:\;7.4\;{\mu}g/ml)$ and the ethyl acetate fraction of Corydalis ternata $(root,\;IC_{50}:\;7.5\;{\mu}g/ml)$ were the most effective on the inhibition of TPA-induced ODC activity, These active fractions are under investigation with further sequential fractionation using column chromatography.

• 생명과학회지
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• 제29권7호
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• pp.779-784
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• 2019

도라지의 탈모예방 효과를 검증하기 위해 몇가지 용매를 이용하여 도라지 분획물을 준비하였다. 산화적 스트레스는 두피혈관을 좁게 하여 모근으로의 영양공급을 방해함으로써 탈모를 유발한다. 본 연구에 사용된 분획물인 BF와 WF는 DPPH 라디칼 소거능의 $IC_{50}$값이 각각 16.2 mg/ml와 121.8 mg/ml로, 모두 농도의존적으로 소거능이 증가하는 것으로 나타났다. 또한 ABTS 라디칼 소거능 실험결과에서도 BF와 WF 처리시 $IC_{50}$값이 각각 4.9 mg/ml와 39.8 mg/ml로 높은 항산화활성을 나타내었다. 또한 인간피부세포인 HaCaT cell 증식 실험결과, 24시간 BF와 WF 처리 시 각각 최대 31%($1{\mu}g/ml$)와 18%($1{\mu}g/ml$)로 HaCaT cell 증식을 촉진시키는 것으로 나타나 추출물이 피부재생효과가 있음을 증명하였다. 탈모의 원인중의 하나인 두피의 염증에 대한 분획물의 효능을 확인하고자, RAW264.7 cell을 이용하여 염증반응 생성물인 NO와 $PGE_2$ 생성정도를 관찰하였다. 그 결과, BF와 WF 각각 최대 88.5%($0.1{\mu}g/ml$)와 88.0%($50{\mu}g/ml$)까지 NO와 $PGE_2$ 생성을 저해하는 것으로 나타났다. 모낭을 구성하는 모유두세포인 HFDPC cell 증식 실험 결과, 4, 48, 72시간 처리 시 모두 HFDPC cell 증식을 농도의존적으로 증가시키는 것으로 나타났다. 이상의 결과를 토대로 본 연구에 사용된 도라지로부터 추출한 부탄올 분획물과 물 분획물이 탈모예방에 효과적이며, 그중에서도 특히 부탄올 분획물이 탈모예방제품의 유용한 천연재료로써의 가치가 있음을 증명하였다.

• 생약학회지
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• 제24권2호
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• pp.159-165
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• 1993

The studies were conducted to investigate the effect of Sinhyo-Taklee-San(STS), which is composed of Astragali Radix(AR), Lonicerae Flos(LF), Angelicae gigantis Radix(AGR) and Glycyrrhizae Radix(GR), on the proliferation of fibroblast cell(Balb/c 3T3). STS, GR and glycyrrhizin increased the proliferation of 3T3 cells. The 10% serum obtained from STS, AR, LF, AGR and GR treated mice also increased the proliferation of 3T3 cells markedly. GR, glycyrrhizin and glycyrrhetinic acid inhibited protein synthesis, but did not affect on DNA synthesis.

• Animal cells and systems
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• 제7권4호
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• pp.303-307
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• 2003

The aim of this study is to investigate whether alcohol alters learning and memory processes pertaining to emotional and spatial factors using the active avoidance and T-maze task in zebrafish. In the active avoidance task, zebrafish were trained to escape from one compartment to another to avoid electric shocks (unconditioned stimulus) following a conditioned light signal. Acquisition of active avoidance task appeared to be normal in zebrafish that were treated with 1% alcohol for 30 min for 17 days until the end of the behavioral test, and retention ability of learned behavior, tested 2 days later, was the same as control group. In the T-maze task, the time to find a reservoir was compared. While the latency was similar during the 1 st training session between control and alcohol-treated zebrafish, it was significantly longer in alcohol-treated zebrafish during retention test 24 h later. Furthermore, when alcohol was treated 30 min after 2nd session without prior treatment, zebrafish demonstrated similar retention ability compared to control. These results suggest that chronic alcohol treatment alters spatial learning of zebrafish, but not emotional learning.

• IMMUNE NETWORK
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• 제13권1호
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• pp.16-24
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• 2013

CTLA-4Ig is regarded as an inhibitory agent of the T cell proliferation via blocking the costimulatory signal which is essential for full T cell activation. To improve applicability, we developed the CTLA-4Ig-CTKC in which the c-terminal lysine had been replaced by cysteine through single amino acid change. The single amino acid mutation of c-terminus of CTLA-4Ig was performed by PCR and was checked by in vitro transcription and translation. DNA construct of mutant form was transfected to Chinese hamster ovary (CHO) cells by electroporation. The purified proteins were confirmed by Western blot and B7-1 binding assay for their binding ability. The suppressive capacity of CTLA-4Ig-CTKC was evaluated by the mixed lymphocyte reaction (MLR) and in the allogeneic pancreatic islet transplantation model. CTLA-4Ig-CTKC maintained binding ability to B7-1 molecule and effectively inhibits T cell proliferation in MLR. In the murine allogeneic pancreatic islet transplantation, short-term treatment of CTLA-4Ig-CTKC prolonged the graft survival over 100 days. CTLA-4Ig-CTKC effectively inhibits immune response both in MLR and in allogeneic islet transplantation model, indicating that single amino acid mutation does not affect the inhibitory function of CTLA-4Ig. CTLA-4Ig-CTKC can be used in vehicle-mediated drug delivery system such as liposome conjugation.