• IMMUNE NETWORK
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• 제13권3호
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• pp.94-101
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• 2013

Amorphous silica particles, whose applications are increasing in many biomedical fields, are known to be less toxic than crystalline silica. In this study, the inflammatory effects of amorphous silica nanoparticles were investigated using 30-nm amorphous silica nanoparticles and human peripheral blood mononuclear cells (PBMCs) or purified monocytes. As a result, production of IL-$1{\beta}$ and IL-8 were increased. In addition, the mitochondrial reactive oxygen species (ROS) was detected, which may lead to mitochondrial membrane disruption. Most importantly, inflammasome formation was observed. Therefore, these results provide immunological information about amorphous silica nanoparticles and suggest that amorphous silica nanoparticles can evoke innate immune reactions in human monocytes through production of IL-$1{\beta}$ and IL-8.

• 대한의생명과학회지
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• 제19권4호
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• pp.344-347
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• 2013

The S100A8 and S100A9 proteins play important roles in inflammatory diseases. The house dust mite acts as a major allergen that induces allergic diseases. We investigated the effect of the house dust mite on S100A8 and S100A9 protein expression in monocytes. We also examined the effect of CCL2, a powerful monocyte chemoattractant, on the expression of both proteins. Extract of Dermatophagoides pteronissinus (DP), recombinant Der p 1 and Der p 2, or CCL2 had no effect on S100A8 and S100A9 expression in human monocytic THP-1 cells. Monocytes were isolated from healthy donors and treated with DP, Der p 1, and Der p 2. S100A8 expression in monocytes increased after a 24 h stimulation with DP, Der p 1, and Der p 2, and CCL2 also increased S100A8 production. However, S100A9 expression in monocytes was not altered by DP, Der p 1, Der p 2, or CCL2. These results indicate that house dust mite and CCL2 may trigger an inflammatory response by altering S100A8 expression.

• 대한의생명과학회지
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• 제29권2호
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• pp.66-74
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• 2023

Triglyceride (TG) accumulation can cause monocytic death and suppress innate immunity. However, the signaling pathways involved in this phenomenon are not fully understood. This study aimed to examine whether inducible nitric oxide synthase (iNOS) is involved in the TG-induced death of THP-1 monocytes. Results showed that iNOS was upregulated in TG-treated THP-1 monocytes, and iNOS inhibition blocked TG-induced monocytic death. In addition, TG-induced poly (ADP-ribose) polymerase (PARP) cleavage and caspase-3 and -7 activation were suppressed by iNOS inhibition. Furthermore, the expression of X-linked inhibitor of apoptosis protein (XIAP) and survivin, which inhibit caspase-3 and -7, was reduced in TG-treated THP-1 monocytes, but iNOS inhibition recovered the TG-induced downregulation of XIAP and survivin expression. Considering that TG-induced monocytic death is triggered by caspase2 and -8, we investigated whether caspase-2 and -8 are linked to the TG-induced expression of iNOS in THP-1 monocytes. When the activities of caspase-2 and -8 were inhibited by specific inhibitors, the TG-induced upregulation of iNOS and downregulation of XIAP and survivin were restored in THP-1 monocytes. These results suggest that TG-induced monocytic death is mediated by the caspase-2/caspase-8/iNOS/XIAP and survivin/executioner caspase/PARP pathways.

• Journal of Periodontal and Implant Science
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• 제30권4호
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• pp.895-913
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• 2000

It is becoming increasingly clear that human gingival fibroblasts(HGF) may play a role in regulating immune responsiveness in inflammatory periodontal lesions. Stimulation of HGF with locally-secreted T cell cytokine $IFN_{\gamma}$ induces human leukocyte antigen class II(HLA II) expression on HGF, which is one of the characteristic feature of professional antigen presenting cells(pAPC). However, $IFN_{\gamma}$-treated HGF and other nonprofessional antigen presenting cells(npAPC) are known to be ineffective or less effective antigen presenter to resting T cells. This study, therefore, was undertaken in an effort to elucidate the differences in expression of cell surface molecules between npAPC in periodontal tissues, such as HGF and periodontal ligament fibroblasts(PDLF), and pAPC such as monocytes/macrophages. Using flow cytometry, the levels of cell surface expression of HLA-D, ICAM-1, LFA-3, and B7-1, which are involved in antigen presentation, were determined in HGF, PDLF and human myelomonocytic cell line THP-1. $IFN_{\gamma}$ clearly induced HLA-D expression on both of fibroblasts and monocytes dose dependently. However, expression level on monocytes were 4 to 5 times higher than that on fibroblasts, and induction rate was faster in monocytes than in fibroblasts. The levels of ICAM-1 expression on fibroblasts and monocytes were enhanced by $IFN_{\gamma}$ in a dose dependent manner. On the other hand, the expression of LFA-3 molecule, which could be detected in fibroblasts and monocytes without cytokine stimulation, was no more enhanced by addition of $IFN_{\gamma}$. B7-1, important costimulatory molecule in T cell activation and proliferation, was not detected on both of fibroblasts and monocytes even when stimulated with $IFN_{\gamma}$, except on monocytes fully differentiated by pretreatment of PMA and treated by $IFN_{\gamma}$. These results suggest that delayed expression of HLA-D and absence of B7-1 on $IFN_{\gamma}$ - treated fibroblasts may at least in part be involved in the ineffectiveness of fibroblasts as primary APC. And it is postulated that although periodontal fibroblasts may not serve as primary APC in normal periodontium, sustained expression of HLA II on ubiquitous fibroblasts in inflammatory lesions may perpetuate immune responses and produce chronic inflammation and tissue injury.

• 대한핵의학회지
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• 제36권2호
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• pp.110-120
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• 2002

목적: FDG PET은 악성종양의 진단에 유용하게 쓰이고 있으나, 염증에도 섭취되어 진단에 어려움이 있다. 염증에서 F-18-FDG 섭취는 단핵세포에서 포도당대사가 항진되어 나타난다. 이 연구에서는 사람의 암세포와 단핵세포간에 포도당대사에 차이가 있는지 알아보고자 하였다. 대상 및 방법: 사람의 대장암 세포주(SNU-C2A, SNU-C4, SNU-C5)와 폐암 세포주(NCI-H522), 단핵세포를 포도당 농도가 다른 배지에서 각각 배양시키고, FDG 섭취와 포도당운반체 1(Glut1)의 발현, hexokinase 활성도의 변화를 비교 분석하였다. 결과: 포도당이 없는 배지에서는 암세포와 단핵세포 모두에서 FDG 섭취가 증가되나 포도당 고농도(16.7 mM)에서는 섭취가 감소하였다. 이 고농도에서 Glut1 mRNA의 발현은 대장암 세포주, 폐암 세포주에서 감소하였다. 고농도의 포도당 배지에서 Glut1 단백질의 발현도 4종류의 암세포에서 모두 감소하였으나, 단핵세포에서는 변화가 없었다. SNU-C2A, SNU-C4, NCI-H522 세포에서 hexokinase의 활성도는 비슷하였고, 단핵세포와 SNU-C5에서는 약간 증가하였다. 결론: 포도당 섭취에 있어서 사람의 암 세포주와 단핵세포는 서로 다른 기전을 보이고 있다. 대장암 세포는 포도당 농도에 의한 포도당 섭취 변화가 Glut1에 의하여 조절되나, 단핵세포는 다른 기전을 가지고 있다.

• IMMUNE NETWORK
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• 제22권5호
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• pp.40.1-40.24
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• 2022

Mesenchymal stem cells (MSCs) are attractive alternatives to conventional anti-asthmatic drugs for severe asthma. Mechanisms underlying the anti-asthmatic effects of MSCs have not yet been elucidated. This study evaluated the anti-asthmatic effects of intravenously administered MSCs, focusing on macrophages and monocytes. Seven-week-old transgenic (Tg) mice with lung-specific overexpression of IL-13 were used to simulate chronic asthma. MSCs were intravenously administered four days before sampling. We examined changes in immune cell subpopulations, gene expression, and histological phenotypes. IL-13 Tg mice exhibited diverse features of chronic asthma, including severe type 2 inflammation, airway fibrosis, and mucus metaplasia. Intravenous administration of MSCs attenuated these asthmatic features just four days after a single treatment. MSC treatment significantly reduced SiglecF^-CD11c^-CD11b⁺ monocyte-derived macrophages (MoMs) and inhibited the polarization of MoMs into M2 macrophages, especially M2a and M2c. Furthermore, MSCs downregulated the excessive accumulation of Ly6c^- monocytes in the lungs. While an intravenous adoptive transfer of Ly6c^- monocytes promoted the infiltration of MoM and Th2 inflammation, that of MSC-exposed Ly6c^- monocytes did not. Ex vivo Ly6c^- MoMs upregulated M2-related genes, which were reduced by MSC treatment. Molecules secreted by Ly6c^- MoMs from IL-13 Tg mice lungs upregulated the expression of fibrosis-related genes in fibroblasts, which were also suppressed by MSC treatment. In conclusion, intravenously administered MSCs attenuate asthma phenotypes of chronic asthma by modulating macrophages. Identifying M2 macrophage subtypes revealed that exposure to MSCs transforms the phenotype and function of macrophages. We suggest that Ly6c^- monocytes could be a therapeutic target for asthma management.

• Journal of Nutrition and Health
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• 제24권2호
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• pp.97-103
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• 1991

에탄올이 면역계의 항원전달세포이며, 동시에 감마인터페론 등의 림포카인에 의해 활성화되면 작동세포의 역활을 하는 단핵구-대식세포의 arachildonic acid 대사의 cyclooxygenasc 경로의 프로스타글라딘 생산에 미치는 영향을 연구하기 위하여 감마 인터페론으로 전처치하여 활성화시킨 단핵구와 대조군 단핵구를 사용하여 방사면역측정법으로 프로스타글라딘들을 측정하였다. 건강한 성인의 말초혈액으로 Ficoll-Hypaque용액을 이용한 농도구배법과 젤라틴 피복 플라스크를 이용하여 단핵구를 순수하게 분리한 다음 800단위의 감마 인터페론을 사용하여 3일동안 단핵구를 활성화시켰다. 감마인터페론으로 활성화 시키지 않은 $10^6$개의 단핵구에 100mM,300mM,600mM의 에탄올을 30분간 반응시킨 후 6시간후에 thromboxane B$_2$, PGEB$_2$ 와 6-keto-PGF1$\alpha$ 와 PGE$_2$ 모두 대조군에 비하여 생산이 증가하였다. 감마인터페론으로 전처치한 경우에는 알코올 처치에 관계없이 세가지 프로스타글란딘들 모두 6시간과 24시간에서 대조군보다 감소되었다. 이와같은 성적들로 미루어 볼 때 감마인터페론 처치가 에탄올로 유발한 단핵구 arachidonic acid 대사의 변화를 억제한다고 사료된다.

• 대한의생명과학회지
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• 제22권4호
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• pp.220-226
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• 2016

Hypertriglyceridemia induces atherosclerosis and accordingly is a major causative factor in cardiovascular diseases. Macrophages that develop into foam cells are a crucial component in the development of atherosclerosis. Monocytes can be differentiated into M1 or M2 macrophages. M1 macrophages promote inflammatory responses, whereas M2 macrophages exhibit anti-inflammatory activity. Recently, we found that triglyceride (TG)-treated THP-1 monocytes express a variety of macrophage-specific surface markers, indicating that TG treatment could trigger the differentiation of monocytes into macrophages. In this study, we investigated whether TG-induced macrophages express the M1 or the M2 macrophage phenotype. THP-1 cells were treated with various concentrations of TG for different times and the expression of M1- and M2-specific markers was evaluated by RT-PCR. We found increased expression of M1 markers (CD40, CD80, and CD86) in TG-treated THP-1 cells in a TG dose- and time-dependent manner. The expression of M2 markers (CD163, CD200R, and CD206) showed variable responses to TG treatment. Taken together, our results indicate that TG treatment triggers the differentiation of monocytes into M1 macrophages, rather than into M2 macrophages, suggesting that TG contributes to pro-inflammatory responses.

• BMB Reports
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• 제42권9호
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• pp.574-579
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• 2009

The regulatory effects of honokiol on the cellular responses of macrophages and monocytes were evaluated. Specifically, we investigated the effects of honokiol with respect to lipopolysaccharide (LPS)-induced cytotoxicity, LPS- or phorbol-12-myristate-13-acetate (PMA)-mediated morphological changes, and relevant events (FITC-dextran-induced phagocytic uptake). Honokiol blocked the LPS-induced cytotoxicity of RAW264.7 cells in a dose-dependent manner. In addition, honokiol appeared to block the production of cytotoxic cytokines such as interleukin (IL)-$1{\beta}$ and tumor necrosis factor (TNF)-$\alpha$, nitric oxide (NO), and reactive oxygen species (ROS). Moreover, honokiol strongly prevented the morphological changes in RAW 264.7 and U937 cells that were induced by LPS and PMA. The surface levels of marker proteins, which are up-regulated under the morphological changes of RAW264.7 and U937 cells, were also diminished. The data presented here strongly suggest that the honokiol modulates various cellular responses managed by macrophages and monocytes.

• Journal of Ginseng Research
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• 제37권3호
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• pp.300-307
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• 2013

20S-dihydroprotopanaxatriol (2H-PPT) is a derivative of protopanaxatrol from ginseng. Unlike other components from Panax ginseng, the pharmacological activity of this compound has not been fully elucidated. In this study, we investigated the modulatory activity of 2H-PPT on the cellular responses of monocytes and macrophages to understand its immunoregulatory actions. 2H-PPT strongly upregulated the release of radicals in sodium nitroprusside-treated RAW264.7 cells and the surface levels of costimulatory molecule CD86. More importantly, this compound remarkably suppressed nitric oxide production, morphological changes, phagocytic uptake, cell-cell aggregation, and cell-matrix adhesion in RAW264.7 and U937 cells in the presence or absence of lipopolysaccharide, anti-CD43 antibody, fibronectin, and phorbal 12-myristate 13-acetate. Therefore, our results suggest that 2H-PPT can be applied as a novel functional immunoregulator of macrophages and monocytes.