• 한국응용곤충학회지
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• 제42권4호
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• pp.353-360
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• 2003

곤충병원세균이 효과적으로 병원력을 발휘하는 데 대상 곤충의 면역저하가 요구될 수 있다. 본 연구는 대상곤충의 면역저하가 병원세균의 살충능력에 직접 연관된다는 가설을 세웠다. 곤충병원세균을 5령 누에(Bombyx mori)의 혈강에 접종하였을 때, X. nematophilus는 다른 곤충병원세균인 Staphyiococcus gallinarum 보다 1,200배 높은 병원력을 보였다. 비록, 두 곤충병원세균은 누에의 혈구세포에 대해서 독성효과를 가지고 있지만, X. nematophiius는 S. gallinarum과 비교해보다 빠르고 높은 세포독성 영향을 보였다. 세포성 면역반응에서 5${\times}$$10^{5}$농도로 세균이 접종되었을 때, 누에는 약 20개 정도의 소낭을 형성하였다. 특히, 살아있는 X. nematophilus가 접종된 누에에서 소낭 형성은 크게 감소하였지만, S. gullinarum은 소낭 형성 감소에 영향을 주지 않았다. 두 세균 모두는 prophenoloxidase (proPO)의 활성화를 억제시켰다. 그러나 X. nematophilus.가 S. gallinarum보다 높게 PO 활성화를 억제시켰다. 라이소자임의 활성유도는 S. gallinarum접종 후 4시간에서 관찰되었으나, X. nematophilus를 접종하였을 때는 라이소자임의 활성이 전혀 관찰되지 않았다 이러한 결과들은 누에에서 X. nematophilus가 S. gallinarum보다 더 큰 면역저하를 유발하여 병원성을 높였다는 것을 보여준다. 따라서 본 연구는 곤충병원세균에 의해서 유발된 면역저하는 곤충병원세균의 병원성과 연관되어 있다는 것을 제시한다.다.

• BMB Reports
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• 제51권2호
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• pp.92-97
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• 2018

B cell leukemia/lymphoma 3 (Bcl3) plays a pivotal role in immune homeostasis, cellular proliferation, and cell survival, as a co-activator or co-repressor of transcription of the $NF-{\kappa}B$ family. Recently, it was reported that Bcl3 positively regulates pluripotency genes, including Oct4, in mouse embryonic stem cells (mESCs). However, the role of Bcl3 in the maintenance of pluripotency and self-renewal activity is not fully established. Here, we report the dynamic regulation of the proliferation, pluripotency, and self-renewal of mESCs by Bcl3 via an influence on Nanog transcriptional activity. Bcl3 expression is predominantly observed in immature mESCs, but significantly decreased during cell differentiation by LIF depletion and in mESC-derived EBs. Importantly, the knockdown of Bcl3 resulted in the loss of self-renewal ability and decreased cell proliferation. Similarly, the ectopic expression of Bcl3 also resulted in a significant reduction of proliferation, and the self-renewal of mESCs was demonstrated by alkaline phosphatase staining and clonogenic single cell-derived colony assay. We further examined that Bcl3-mediated regulation of Nanog transcriptional activity in mESCs, which indicated that Bcl3 acts as a transcriptional repressor of Nanog expression in mESCs. In conclusion, we demonstrated that a sufficient concentration of Bcl3 in mESCs plays a critical role in the maintenance of pluripotency and the self-renewal of mESCs via the regulation of Nanog transcriptional activity.

• Molecular & Cellular Toxicology
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• 제5권1호
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• pp.32-43
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• 2009

Acetaminophen (APAP) overdose is known to cause severe hepatotoxicity mainly through the depletion of glutathione. In this study, we compared the cytotoxic effects of APAP on both a normal murine hepatic cell line, BNL CL.2, and its SV40-transformed cell line, BNL SV A.8. Gene expression profiles for APAP-treated cells were also obtained using microarray and analyzed to identify differences in genes or profiles that may explain the differences of susceptibility to APAP in these cell lines. These two cell lines exhibited different susceptibilities to APAP (0-$5,000{\mu}M$); BNL SV A.8 cells were more susceptible to APAP treatment compared to BNL CL.2 cells. A dose of $625{\mu}M$ APAP, which produced significant differences in cytotoxicity in these cell lines, was tested. Microarray analysis was performed to identify significant differentially expressed genes (DEGs) irrespective of APAP treatment. Genes up-regulated in BNL SV A.8 cells were associated with immune response, defense response, and apoptosis, while down-regulated genes were associated with catalytic activity, cell adhesion and the cytochrome P450 family. Consistent with the cytotoxicity data, no significant DEGs were found in BNL CL.2 cells after treatment with $625{\mu}M$ APAP, while cell cycle arrest and apoptosis-related genes were up-regulated in BNL SV A.8 cells. Based on the significant fold-changes in their expression, a genes were selected and their expressions were confirmed by quantitative real-time RT-PCR; there was a high correlation between them. These results suggest that gene expression profiles may provide a useful method for evaluating drug sensitivity of cell lines and eliciting the underlying molecular mechanism. We further compared the genes identified from our current in vitro studies to the genes previously identified in our lab as regulated by APAP in both C57BL/6 and ICR mice in vivo. We found that a few genes are regulated in a similar pattern both in vivo and in vitro. These genes might be useful to develop as in vitro biomarkers for predicting in vivo hepatotoxicity. Based on our results, we suggest that gene expression profiles may provide useful information for elucidating the underlying molecular mechanisms of drug susceptibility and for evaluating drug sensitivity in vitro for extrapolation to in vivo.

• Asian-Australasian Journal of Animal Sciences
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• 제15권7호
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• pp.1066-1070
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• 2002

10 male piglets at 5-6 weeks old with similar body weight (BW) were randomly assigned into the experimental (EXP) and control (CON) groups. The animals in EXP received intro-muscular injection with daidzein (DA) at the dose of 0.5 mg DA per kg start BW on day 1. The same procedures were repeated once every 3 days for eight times. The animals in CON received the injection only with same volume of control peanut oil. The animals were weighted on day 14 and 28 and the blood samples were obtained at different stages of the treatment for determining IGF-I levels and blood parameters. At the end of the experiment, the thymus and spleen from all the animals were surgically taken out and weighted. The results showed that BW and average daily gain (ADG) were not significantly different between the groups in term of the whole period, but ADG between days 14-28 was higher in EXP than in CON (p<0.05). On days 18, 21 and 25, IGF-I levels in EXP group were 20.53% (p<0.05), 15.92% (p>0.05) and 23.46% (p<0.05), respectively, higher than those in CON. The weights of thymus and spleen, the ratios of their weights to BW and red blood count (RBC) did not significantly differ between the groups at all stages. White blood count (WBC) in EXP steadily increased from day 22, reached its apex on day 24, which was higher than in CON (p<0.05) and its own levels on day 20 and 22 (p<0.01 or p<0.05), and remained higher on the later time (p=0.058). The results of percentage of T-Lymphocytes also demonstrated similar trend to WBC, but TLymphocyte transformation rate (%) appeared no significant change between the groups. In conclusion, Daidzein could stimulate male piglet growth and elevate serum IGF-I levels at certain stages of the treatment. It could also increase WBC and T-Lymphocyte rates, but had no significant impacts on RBC and T-Lymphocyte transformation rate.

• Parasites, Hosts and Diseases
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• 제30권1호
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• pp.43-48
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• 1992

폐흡충(Paragonimus westermani) 피낭유충을 마우스에 감염시킨 후 in vitro상에서 비장 림프구에 폐흡충 항원, phytohemagglutinin(PHA) 및 혈청 첨가시 림프구 아세포화 반응을 관찰하였다. PHA로 자극시킨 감염 마우스의 비장 림프구는 비감염군에 비해 감염 1 주 후에 평균 53.6%의 유의한 증식 억제를 관찰하였고, 폐흡충 성충항원으로 자극시킨 경우 감염 마우스의 비장 림프구의 증식은 감염 1 주 후부터 6 주까지 비감염군에 비해 중가되었으며 특히 감염 1 주와 4 주 후에는 각각 평균 200.9% 및 280.2%의 유의한 수준으로 증가되었다. 또한 피낭유충 항원으로 감염 마우스의 비장 림프구를 자극시에도 비감염군의 림프구의 증식에 비해 전반적으로 증가되었으며 특히 감염 4 주 째에는 평균 180.5%의 유의한 수준으로 증가하였다. 폐홉충에 감염된 마우스의 감염 4 주 째 혈청을 PHA로 자극시킨 비감염 마우스 비장 림프구에 첨가하였을 때 유의한 수준의 증식의 억제를 관찰하였다. 이러한 결과들로 보아 폐흡충 감염 마우스에서 림프구가 세포 매개성 면역에 관여하며 감염 혈청이 PHA에 대한 T 림프구의 증식을 억제함을 알 수 있었다.

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2008년도 International Meeting of the Microbiological Society of Korea
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• pp.42-44
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• 2008

Bacterial biofilms are analogous to multi-cellular organisms or to clonal communities of higher organisms. In this respect, it can be demonstrated that biofilms display the type of genetic variation associated with macroorganisms. The formation of genetic variants from biofilms is the result of internally produced and regulated signals and the appearance of these variants coincides with dispersal from the biofilm. Moreover, the generation of such variation, has similar outcomes for the bacterial community, where diversification of phenotypic traits ensures that the bacterial community optimizes its chances of success when dispersing or surviving when challenged with environmental stress. These observations increase the complexity with which we view bacteria and also suggest that microbial systems can serve as models for the testing of eukaryotic ecological theories.

• 한국식품위생안전성학회지
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• 제22권1호
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• pp.1-14
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• 2007

The term, "food safety", has traditionally been viewed as a practical science aimed at assuring the prevention acute illnesses caused by biological microorganisms, and only to a minor extent, chronic diseases cause by chronic low level exposures to natural and synthetic chemicals or pollutants. "food safety" meant to prevent microbiological agents/toxins in/on foods, due to contamination any where from "farm to Fork", from causing acute health effects, especially to the young, immune-compromised, genetically-predisposed and elderly. However, today a broader view must also include the fact that diet, perse (nutrients, vitamins/minerals, calories), as well as low level toxins and pollutant or supplemented synthetic chemicals, can alter gene expressions of stem/progenitor/terminally-differentiated cells, leading to chronic inflammation and other mal-functions that could lead to diseases such as cancer, diabetes, atherogenesis and possibly reproductive and neurological disorders. Understanding of the mechanisms by which natural or synthetic chemical toxins/toxicants, in/on food, interact with the pathogenesis of acute and chronic diseases, should lead to a "systems" approach to "food safety". Clearly, the interactions of diet/food with the genetic background, gender, and developmental state of the individual, together with (a) interactions of other endogenous/exogenous chemicals/drugs; (b) the specific biology of the cells being affected; (c) the mechanisms by which the presence or absence of toxins/toxicants and nutrients work to cause toxicities; and (d) how those mechanisms affect the pathogenesis of acute and/or chronic diseases, must be integrated into a "system" approach. Mechanisms of how toxins/toxicants cause cellular toxicities, such as mutagenesis; cytotoxicity and altered gene expression, must take into account (a) irreversible or reversal changes caused by these toxins or toxicants; (b)concepts of thresholds or no-thresholds of action; and (c) concepts of differential effects on stem cells, progenitor cells and terminally differentiated cells in different organs. This brief Commentary tries to illustrate this complex interaction between what is on/in foods with one disease, namely cancer. Since the understanding of cancer, while still incomplete, can shed light on the multiple ways that toxins/toxicants, as well as dietary modulation of nutrients/vitamins/metals/ calories, can either enhance or reduce the risk to cancer. In particular, diets that alter the embryo-fetal micro-environment might dramatically alter disease formation later in life. In effect "food safety" can not be assessed without understanding how food could be 'toxic', or how that mechanism of toxicity interacts with the pathogenesis of any disease.

• 대한소아치과학회지
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• 제37권3호
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• pp.275-287
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• 2010

치아 우식증은 범발성 질환이고 이에 대한 생체반응은 단순하지 않으며 질병 과정과 숙주의 활성 모두를 반영하는 복합적인 반응이다. 이러한 반응을 이해하기 위해서는 질병의 세포학적, 분자학적인 면을 이해하는 것이 필수적이다. 이에 본 연구는 임상적으로 건강한 치아와 우식이 진행된 치아로부터 얻어진 치수 안의 유전자 발현을 규명하고 우식 병소에서 일어나는 치유 및 재생에 관계되는 분자와 면역 세포들 사이의 분자 생화학적 상호작용을 규명하기 위해서 우식치아와 건전치아의 치수를 이용하여 cDNA 미세배열(microarray) 분석과 역전사효소 중합효소 연쇄반응 (RT-PCR) 분석, 그리고 면역화학염색법 (immunohistochemistry)을 시행하여 다음과 같은 결론을 얻었다. 1. cDNA 미세배열 분석 결과, 건전치아군인 대조군에서는 143개의 유전자가, 우식치아군인 실험군에서는 377개의 유전자가 1.6배이상 발현되었다. 2. 역전사효소 중합효소 연쇄반응 분석에서 14개의 유전자를 선택하였고 cDNA 미세배열 분석결과와 동일한 결과를 확인하였다. 3. TGF-${\beta}1$의 면역조직화학적 관찰 결과, 건전치에 비해 우식치의 상아모세포와 치수에서 특히 강하게 발현되었다.

• 생명과학회지
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• 제26권9호
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• pp.1027-1032
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• 2016

항원은 병원체로부터 유래한 질병인자다. 생명체는 항원에 대항하는 방어계인 면역계를 가지고 있다. 항원은 식세포작용, 항체, 보체 활성화, NK세포 혹은 MHC 분자를 통한 세포독성 T세포와 같은 방법을 통해서 처리된다. 림프절은 스트로마세포와 3차원 네트워크를 통해서 구성되어 있다. Fibroblastic reticular cells (FRC)는 림프절 T zone에서 T세포와 상호작용한다. FRC는 세포외 기질 생산과 homing 케모카인을 생산하여 감염에 대비한다. 하지만, FRC가 항원처리과정에 관련되어있다는 보고는 없다. 본 연구는 FRC의 항원처리 관련성에 대한 연구이다. 이를 위해 FRC는 대식세포, T세포, LPS, 그리고 TNFα와 같은 다양한 감염상황에 노출시켜 연구를 진행하였다. FRC가 대식세포 및 T세포와 공배양 했을 때 FRC가 형태적 변화와 FRC간 빈 공간 형성이 관찰 되었다. MMP 활성은 Y27632와 T세포에 의해 조절 되었다. 더욱이, 염증물질인 TNFα를 FRC에 처리 후 마이크로어레이를 통한 결과에서 부착분자와 MHC I antigen transporter의 발현을 조절하는 것으로 나타났다. FRC 단일층에 LPS와 대식 세포를 공배양 했을 때 NO 생성력이 크게 향상되었다. GFP antigen을 FRC와 대식세포 공배양군에 처리 했을 때 항원 흡수율이 증가되었다. 이러 결과는 FRC가 항원처리에 관여하고 있다는 것을 의미하며 이는 림프절이 항원처리과정에 연관되어 있다는 것을 제시한다.

• Molecules and Cells
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• 제26권1호
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• pp.67-73
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• 2008

Herpetic stromal keratitis (HSK) is an inflammatory disorder induced by HSV-1 infection and characterized by T cell-dependent destruction of corneal tissues. It is not known what triggers $CD4^+$ T cell migration into the stroma of HSV-1-infected corneas. The keratocyte is a fibroblast-like cell that can function as an antigen-presenting cell in the mouse cornea by expressing MHC class II and costimulatory molecules after HSV-1 infection. We hypothesized that chemokines produced by stromal keratocytes are involved in $CD4^+$ T cell infiltration into the cornea. We found that keratocytes produce several cytokines and chemokines, including MCP-1, RANTES, and T cell activation (TCA)-3. HSV-1 infection increased the production of MCP-1 and RANTES by keratocytes, and these acted as chemoattractants for HSV-1-primed $CD4^+$ T cells expressing CCR2 and CCR5. ExpreHerpetic stromal keratitis (HSK) is an inflammatory disorder induced by HSV-1 infection and characterized by T cell-dependent destruction of corneal tissues. It is not known what triggers $CD4^+$ T cell migration into the stroma of HSV-1-infected corneas. The keratocyte is a fibroblast-like cell that can function as an antigen-presenting cell in the mouse cornea by expressing MHC class II and costimulatory molecules after HSV-1 infection. We hypothesized that chemokines produced by stromal keratocytes are involved in $CD4^+$ T cell infiltration into the cornea. We found that keratocytes produce several cytokines and chemokines, including MCP-1, RANTES, and T cell activation (TCA)-3. HSV-1 infection increased the production of MCP-1 and RANTES by keratocytes, and these acted as chemoattractants for HSV-1-primed $CD4^+$ T cells expressing CCR2 and CCR5. Expression of MCP-1 in the corneal stroma was confirmed in vivo. Finally, when HSV-1-primed $CD4^+$ T cells were adoptively transferred into wild type and MCP-1-deficient mice that had been sublethally irradiated to minimize chemokine production from immune cells, infiltration of $CD4^+$ T cells was markedly reduced in the MCP-1-deficient mice, suggesting that it is the MCP-1 from HSV-1-infected keratocytes that attracts $CD4^+$ T cells into the cornea.