• 한국식품과학회지
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• 제31권4호
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• pp.1035-1043
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• 1999

김치, 젓갈 등 전통 발효식품에서 분리한 유용 박테리오신 생산균주 및 이 균주가 생산하는 박테리오신에 의한 식품에서 발생하기 쉬운 주요 부패 및 병원성 세균에 대한 항균효과를 검정하여, 무독성 천연방부제로서의 향후 식품 및 생물산업에서의 활용 가능성을 검토하였다. 젓갈에서 분리한 LAB NK24는 Lactococcus lactis NK24로 잠정적으로 동정되었으며, 이 박테리오신 생산균주는 deferred method에서는 모든 대상균주에 대해서 항균활성을 보였으며, 김치에서 분리한 L. lactis BH5, L. lactis A164 균주에 비해 대체적으로 높은 항균활성을 나타내었다. 젓갈유래 박테리오신인 lacticin NK24는 75%황산암모늄침전법으로 부분정제되었으며, 부분정제된 lacticin NK24는 E. faecalis ATCC 19433 등 그람양성균 10균주, 그람음성균은 E. coli KCCM 32396, P. aeruginosa ATCC 15442 및 S. paucimobilis BNJ 9664 등 3균주에 대하여 항균활성을 보였으며, 효모와 곰팡이에는 활성을 보이지 않았다. 따라서 전통 발효식품인 젓갈에서 분리한 본 박테리오신은 비교적 항균범위가 넓고 식품에서 발생하기 쉬운 주요 부패 및 병원성 세균에 대해 뚜렷한 항균효과를 보이고 있으므로 향후 무독성 천연방부제로서 활용이 가능하리라 판단된다.

• 한국식품과학회지
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• 제44권4호
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• pp.488-492
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• 2012

전통방식으로 숙성되고 있는 한식간장의 표면으로부터 분리된 바위꽃과 메밀꽃이라 불리는 미생물을 18S rDNA ITS1과 ITS4 지역의 염기서열를 분석한 결과, 각각 Cladosporium 종들과 S. halophilus의 염기서열과 높은 상동성을 보였다. 이에 따라 바위꽃 미생물은 Cladosporium sp. NK1로, 메밀꽃 미생물은 S. halophilus NK2로 명명하였다. YPD 액체 배지를 이용한 최적 생장 pH와 온도에 있어서 Cladosporium sp. NK1은 각각 pH 6과 22-$27^{\circ}C$였고, S. halophilus NK2는 각각 pH 5-7과 $22^{\circ}C$였다. Cladosporium sp. NK1는 NaCl를 첨가하지 않은 YPD 액체배지에서 가장 잘 생장하였으나, protease 및 amylase 효소활성에 있어서는 각각 10%와 15% NaCl이 첨가된 YPD 배양액 시료에서 가장 높았다. S. halophilus NK2는 10% NaCl이 첨가된 YPD 액체배지까지 매우 잘 생장하였으며, protease 활성은 10% NaCl이 첨가된 YPD 배양액 시료에서, amylase 활성은 5% NaCl이 첨가된 배양액 시료에서 가장 높았다. Cladosporium sp. NK1과 S. halophilus NK2의 lipase 활성은 보이지 않았다. 간장의 관능평가 결과 Cladosporium sp. NK1 균주는 간장의 맛에서, S. halophilus NK2는 향미에서 유의적 차이를 보였다.

• The Korean Journal of Pain
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• 제31권1호
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• pp.43-49
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• 2018

Background: Chronic pain reportedly exerts complex effects on immune function. Natural killer (NK) cells are lymphocytes that play a critical role in cellular and innate immunity. This study examined changes in the subset populations and cytotoxic activity of peripheral blood NK cells in patients with chronic pain. Methods: Thirty patients with chronic moderate-to-severe pain (group P) and age-matched pain-free subjects (group NoP) were enrolled. Peripheral whole blood was analyzed for the percentage and expression of NK cell surface markers (CD56 and CD16) by flow cytometry. Cytotoxic activity was assayed by evaluating CD69 expression on $CD3^-/CD56^+NK$ cells. Results: The percentage of NK cells among total lymphocytes was not significantly different between groups P and NoP ($16.3{\pm}9.3$ vs. $20.2{\pm}10.5%$). Likewise, the percentages of two major NK cell subsets, $CD56^{bright}$ and $CD56^{dim}$, were also not significantly different between the two groups. However, the percentage of $CD56^{bright}/CD16^+$ subset, was slightly but significantly increased in group P ($1.0{\pm}0.9%$; P< 0.01) compared with group NoP ($0.5{\pm}0.6%$). The cytotoxicity of NK cells was not different between the two groups, showing similar CD69 expression (P vs. $NoP=29.2{\pm}15.2$ vs. $32.0{\pm}15.0%$). These findings were not influenced by pain intensity, opioid use, or disease causing pain in group P. Conclusions: NK cell cytotoxic activity and major subset populations, with the exception of an increased percentage of the $CD56^{bright}/CD16^+$ subset, are not significantly altered in patients with chronic severe pain.

• 동의생리병리학회지
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• 제18권4호
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• pp.995-1000
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• 2004

This study was purposed to investigate the effect of Gamgung-tang(GGT) on immune responses induced by glucocorticoid in mice. GGT solution was treated by intraperitoneal injection for 7 days after glucocorticoid treatment(80㎎/㎏). And then B and T cell proliferation and cytolytic activity of natural killer(NK) cells were measured. There was 25% inhibition in B cell proliferation with treatment of glucocorticoid. However, B cell proliferation was not influenced by GGT treatment. T cell proliferation was also inhibited by 18.4% with treatment of glucocorticoid. On the other hand, T cell proliferation was increased dose-dependent manner in GGT treated group. Furthermore in purified T cell, the proliferation was furtherly increased than non-purified T cell. At concentration of 18㎎/mouse GGT, purified T cell proliferation was increase to above level of normal group. The cytotoxic activity of NK cell was decreased by 35.3% with treatment of glucocorticoid. In GGT treated group, the cytotoxic activity of NK cell was increased to the normal level. In purified NK cell, the cytolytic activity of NK cell was further increased than non-purifed NK cell. These results suggest that GGT may proliferate T cell that is suppressed by glucocorticoid, and activate NK cell activity.

• IMMUNE NETWORK
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• 제7권3호
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• pp.133-140
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• 2007

Background: It is well established that cross talk between natural killer (NK) cells and myeloid dendritic cells (DC) leads to NK cell activation and DC maturation. In the present study, we investigated whether type 1-polarized DC (DC1) matured in the presence of IFN-${\gamma}$ and type 2-polarized DC (DC2) matured in the presence of PGE2 can differentially activate NK cells. Methods: In order to generate DC, plastic adherent monocytes were cultured in RPMI 1640 containing GM-CSF and IL-4. At day 6, maturation was induced by culturing the cells for 2 days with cytokines or PGE2 in the presence or absence of LPS. Each population of DC was cocultured with NK cells for 24 h. The antigen expression on DC was analyzed by flow cytometry and cytokine production in culture supernatant was measured by ELISA or a bioassay for TNF-${\alpha}$ determination. NK cell-mediated lysis was determined using a standard 4h chromium release assay. Results: DC2, unlike DC1, had weak, if any, ability to induce NK cell activation as measured by IFN-${\gamma}$ production and cytolytic activity. DC2 were weakly stimulated by activated NK cells compared to DC1. In addition, IFN-${\gamma}$-primed mature DC appeared to be most resistant to active NK cell-mediated lysis even at a high NK cell/DC ratio. On the other hand, PGE2-primed DC were less resistant to feedback regulation by NK cells than IFN-${\gamma}$-primed mature DC. Finally, we showed that the differential effect of two types of DC population on NK cell activity is not due to differences in their ability to form conjugates with NK cells. Conclusion: These results suggest that different combinations of inflammatory mediators differentially affect the effector function of DC and, as a result, the function of NK cells, eventually leading to distinct levels of activation in adaptive immunity.

• IMMUNE NETWORK
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• 제6권1호
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• pp.6-12
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• 2006

Background: The Hypothalamo-Pituitary-Adrenal (HPA) axis is an important regulator for the body's stress response. As a primary stress responsive system, HPA-axis secretes various neurotransmitters, hormones, and cytokines, which regulates the immune system. Natural killer (NK) cell which is plays an important role in the innate immune response, is specially decreased their numbers and loose cytolytic activity in response to stress. However, the effect of HPA-axis secreted proteins on NK cell activity has not been defined. Herein, we studied the effect of adrenal secreted adiponectin on NK cell cytotoxicity. Adiponectin which is well-known metabolic control protein, plays important roles in various diseases, including hypertension, cardiovascular diseases, inflammatory disorders, and cancer. Methods: Signal sequence trap was used to find stress novel secretory protein from HP A-axis. Selected adiponectin was treated mouse mature primary NK cells and then examined the effect of adiponectin to NK cell cytotoxicity and cytokine expression level. Results: We found that adiponectin which is secreted from adrenal gland, suppress IL-2 induced NK cell cytotoxicity. And also investigated cytolytic cytokines are suppressed by adiponectin. Conclusion: These data suggest that adiponectin inhibites NK cell cytotoxicity via suppression of cytotoxicity related target gene.

• 대한기관식도과학회:학술대회논문집
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• 대한기관식도과학회 1991년도 제25차 학술대회 연제순서 및 초록
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• pp.20-20
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• 1991

악성종양의 발생과 진행에 면역 방어기능이 중요한 역할을 하리라는 가설은 모두가 공감하는 사실이다. 이중 T-lymphocyte와 Natural killer cell (이하 NK cell이라함)은 종양 면역학에 특히 중요한 임파구로 이런 임파구의 혈액분포양상은 면역방어기능을 짐작할 수 있는 간접적인 자료가 될 수 있다. 저자들은 치료전 두경부 악성종양환자에서 혈액을 채취하여 T-lymphocyte와NK cell의 분포양상을 검사하고, 방사선치료 환자에서는 NK cell activity를 측정하였기에 다음과 같은 결과를 보고하는 바이다. 1) 두경부 악성 종양 환자군에서 CD3+ cell은 감소하고 NK cell은 증가하며 CD4/CD8 비율은 변화가 없었다. 2) 병변이 진행되면서 CD3+ cell과 CD4+ cell은 감소하고 NK cell은 증가하였으며 CD4/CD8 비율의 변화는 없었다. 3) 방사선치료에 의해 CD3+ cell과 CD4+ cell, CD4/CD8 비율은 감소하였고, NK cell과CD8+cell은 증가하였다. 4) 방사선치료에 의한 CD4/CD8 비율의 감소와, CD8+ cell의 증가는 NK cell의 증가에 의한 것이라 추정되고, NK cell을 제외하면 CB4/CD8 비율의 변화는 없었다. 5) 방사선치료 환자에서 NK cell activity는 증가하였고, 이런 증가가 T-lymphocyte기능의 감소를 보상해 주고 있었다.

• 대한한의학회지
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• 제25권4호
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• pp.161-170
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• 2004

Objective : The purpose of this study was to investigate the effects of Armillaria mellea extract (AME) on immune modulation focused on anti-cancer activity. Methods : To prove the effects of AME, we performed NO assay, NK cytotoxicity assay and RT-PCR of cytokine related with macrophage and NK cell activity. Results : AME increased NO production produced by macrophages in part. AME also enhanced the NK cell activities in destroying target cells (YAC-1 cells). AME up-regulated gene expression of IL-l, iNOS, TNF-a in RAW 264.7 cells and IL-l, IL-2, IFN-(equation omitted), TNF-a in splenocytes, respectively. Conclusion : From the above results, we assumed that AME is a potential drug for anti-cancer by activation of the macrophages and NK cells.

• Food Science and Biotechnology
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• 제15권2호
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• pp.227-231
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• 2006

Strain NK181 was isolated for probiotic use from jeotkal and based on results of API 50 CHL kit and 16S rDNA sequencing was tentatively named Lactobacillus plantarum NK181. L. plantarum NK181 was highly resistant to artificial gastric juice (pH 2.5) and bile acid and demonstrated strong adherence to Caco-2 cells. In test using API ZYM kit, eight enzymes were produced. Supernatant of L. plantarum NK181 exhibited about 30% 1,1-diphenyl-2-picyryl hedrazyl (DPPH) radical-scavenging activity and reduced cholesterol by 70%. These results demonstrate potential use of L. plantarum NK181 as health-promoting probiotic.

• Nutrition Research and Practice
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• 제11권1호
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• pp.43-50
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• 2017

BACKGROUND/OBJECTIVES: The present study investigated the hypothesis that a highly pure linear ${\beta}$-1,3-glucan produced by Agrobacterium sp. R259 enhances human natural killer (NK) cell activity and suppresses pro-inflammatory cytokines. SUBJECTS/METHODS: In an eight-week, double-blind, randomized, placebo-controlled clinical trial, 83 healthy adults with white blood cell counts of $4,000-8,000cells/{\mu}L$ were participated and randomly assigned to take two capsules per day containing either 350 mg ${\beta}$-1,3-glucan or placebo. Six participants withdrew their study consent or were excluded due to NK cell activity levels outside the normal range. NK cell activity and serum levels of immunoglobulin G (IgG) and cytokines, such as interferon (IFN)-${\gamma}$, interleukin (IL)-2, IL-4, IL-6, IL-10, IL-12 and tumor necrosis factor (TNF)-${\alpha}$ were measured. RESULTS: NK cell activity and the serum levels of IL-10 were significantly higher from baseline to week 8 in the ${\beta}$-glucan group compared with the placebo group (P = 0.048, P = 0.029). Consumption of ${\beta}$-1,3-glucan also significantly increased NK cell activity compared with placebo after adjusting for smoking and stress status (P = 0.009). In particular, the effect of ${\beta}$-1,3-glucan on NK cell activity was greater in participants with severe stress than in those experiencing mild stress. However, the administration ${\beta}$-1,3-glucan did not significantly modulate the levels of IFN-${\gamma}$, IL-2, IL-4, IL-6, IL-12, TNF-${\alpha}$ and IgG compared with the placebo. CONCLUSION: The results showed that supplementation with bacterial ${\beta}$-1,3-glucan significantly increased NK cell activity without causing any adverse effects. Additionally, the beneficial effect of ${\beta}$-1,3-glucan on NK cell activity was greater in participants experiencing severe stress.