• Journal of Microbiology and Biotechnology
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• v.28 no.10
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• pp.1736-1748
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• 2018

Brucella abortus can survive and replicate within host macrophages, and great efforts have been made to demonstrate the genes involved in pathogenicity, such as internalization, in Brucella research. Here, intracellular responses were compared between THP-1 macrophage cells stimulated with B. abortus wild-type and four mutants (C1, C10, C27, and C32) using microarray to demonstrate the role of genes related to intracellular survival and replication. These mutants were generated by deleting genes encoding BAB_RS13225 (4-hydrobenzoate 3-monooxygenase, PHBH), BAB_RS00455 (heme exporter protein cytochrome C, CcmC), BAB_RS03675 (exopolyphosphatase, PPX), and BAB_RS13225 (peptidase M24). The results showed that mutants C1 and C10 induced significant suppression of survival levels and cytokine expression relative to wild-type in the THP-1 macrophage cells. These findings suggest that the BAB_RS13225 and BAB_RS00455 genes play important roles in survival within human macrophages. Conversely, mutants C27 and C32 induced significantly higher survival level than wild-type in the cells inhibiting cellular signal transduction. It is assumed that the BAB_RS03675 and BAB_RS13225 genes play a role in cellular resistance to B. abortus. Therefore, the disrupted genes are involved in B. abortus intracellular growth, and especially in its survival, and they could be effective targets for understanding the intracellular bacterium, B. abortus.

• Journal of Microbiology and Biotechnology
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• v.29 no.1
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• pp.151-159
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• 2019

Lipoteichoic acid isolated from Lactobacillus plantarum K8 (pLTA) alleviates lipopolysaccharide (LPS)-induced excessive inflammation through inhibition of $TNF-{\alpha}$ and interleukin (IL)-6. In addition, pLTA increases the survival rate of mice in a septic shock model. In the current study, we have found that pLTA contributes to homeostasis through regulation of pro- and anti-inflammatory cytokine production. In detail, pLTA decreased the production of IL-10 by phorbol-12-myristate-13-acetate (PMA)-differentiated THP-1 cells stimulated with prostaglandin E2 (PGE-2) and LPS. However, $TNF-{\alpha}$ production which was inhibited by PGE-2+LPS increased by pLTA treatment. The regulatory effects of IL-10 and $TNF-{\alpha}$ induced by PGE-2 and LPS in PMA-differentiated THP-1 cells were mediated by pLTA, but not by other LTAs isolated from either Staphylococcus aureus (aLTA) or L. sakei (sLTA). Further studies revealed that pLTA-mediated IL-10 inhibition and $TNF-{\alpha}$ induction in PGE-2+LPS-stimulated PMA-differentiated THP-1 cells were mediated by dephosphorylation of p38 and phosphorylation of c-Jun N-terminal kinase (JNK), respectively. Reduction of pLTA-mediated IL-10 inhibited the metastasis of breast cancer cells (MDA-MB-231), which was induced by IL-10 or conditioned media prepared from PGE-2+LPS-stimulated PMA-differentiated THP-1 cells. Taken together, our data suggest that pLTA contributes to inflammatory homeostasis through induction of repressed pro-inflammatory cytokines as well as inhibition of excessive anti-inflammatory cytokines.

• IMMUNE NETWORK
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• v.4 no.2
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• pp.116-122
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• 2004

Background: LIGHT (TNFSF14) is a member of tumor necrosis factor superfamily and is the ligand for TR2 (TNFRSF14/HVEM). LIGHT is known to have proinflammatory roles in atherosclerosis. Methods: To find out the expression pattern of LIGHT in atherosclerotic plaques, immunohistochemical analysis was performed on human carotid atherosclerotic plaque specimens. LIGHT induced atherogenic events using human monocytic cell line THP-1 were also investigated. Results: Immunohistochemical analysis revealed expression of LIGHT and TR2 in foam cell rich regions in the atherosclerotic plaques. Double immunohistochemical analysis further confirmed the expression of LIGHT in foam cells. Stimulation of THP-1 cells, which express TR2, with either recombinant LIGHT or immobilized anti-TR2 monoclonal antibody induced interleukin-8 and matrix metalloproteinase(MMP)-9. Electrophoretic mobility shift assay demonstrated that LIGHT induces nuclear localization of transcription factor, nuclear factor $(NF)-{\kappa}B$. LIGHT induced activation of MMP-9 is mediated by $NF-{\kappa}B$, since treatment of THP-1 cells with the $NF-{\kappa}B$ inhibitor PDTC (pyrrolidine dithiocarbamate) completely blocked the activation of MMP-9. Conclusion: These data indicate that LIGHT is expressed in foam cells in atherosclerotic plaques and is involved in atherogenesis through activation of pro-atherogenic cytokine IL-8 and destabilization of plaque by inducing matrix degrading enzyme.

• Journal of Nutrition and Health
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• v.53 no.5
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• pp.452-463
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• 2020

Purpose: Aster tataricus (AT) is one of the Asteraceae perennial herbs used in traditional Chinese medicine. The herb contains various bioactive substances, such as flavonoids, isoflavonoids, and phenolic compounds in the roots, and exhibits a range of effects including anti-bacterial, anti-oxidant, and anti-inflammatory activities. This study compared the immunomodulatory effects of ethanol and water extracts of whole AT, except the roots, and analyzed the molecular mechanisms for the regulatory effects on cytokine secretion from THP-1 cells. Methods: The effects of AT extract on the cell viability and proliferation of THP-1 cells were analyzed using the Cell Counting Kit-8 method. The concentrations of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) in the cell culture supernatant of the AT-treated THP-1 cells were measured using an enzyme-linked immunosorbent assay. The protein levels of cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), inhibitor of nuclear factor kappa B (IκBα), and mitogen-activated protein kinase (MAPK) phosphorylation in the cell lysates were determined by western blotting. Results: The water extract and the ethanol extract of AT did not affect the cell viability, and increased the proliferation of THP-1 cells significantly compared to the vehicle. The water extract increased the secretion of IL-1β from THP-1 cells in a dose-dependent manner, but the ethanol extract had no effect. The expression of COX-2 and iNOS protein and the phosphorylation of MAPK and Akt were induced in AT-treated cells. In addition, IκBα was degraded by AT in a concentration-dependent manner. IL-1β secretion by AT was reduced by extracellular-signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK) inhibitors, while TNF-α secretion was decreased by inhibitors of ERK, p38 MAPK, and JNK. Interestingly, the p38 MAPK inhibitor increased the production of IL-1β by AT further. Conclusion: The water extract of the above-ground parts of AT contains immunomodulatory bioactive substances that stimulate immune cells through the MAPK signaling pathway.

• Molecules and Cells
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• v.38 no.9
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• pp.821-828
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• 2015

Monocytes are the major inflammatory cells that infiltrate most solid tumors in humans. The interaction of tumor cells with infiltrating monocytes and their adhesion to these monocytes play a significant role in altering the tumor to become more aggressive. Recently, exposure to lipopolysaccharide (LPS) was suggested to promote cancer cell adhesion to monocytes; however, little is known about the details of the signaling mechanism involved in this process. In this study, we found that LPS up-regulates ICAM-1 expression in MDA-MB-231 breast cancer cells, which facilitates their adhesion to THP-1 monocytes. In addition, we analyzed the signaling mechanism underlying the up-regulation of ICAM-1 and found that the siRNA-mediated depletion of BLT2 markedly suppressed the LPS-induced expression of ICAM-1 in MDA-MB-231 cells and the subsequent adhesion of these cells to THP-1 monocytes. Moreover, we demonstrated that myeloid differentiation primary response gene 88 (MyD88) lies downstream of LPS/TLR4 and upstream of BLT2 and that this 'MyD88-BLT2' cascade mediates ERK activation and subsequent ICAM-1 expression, which is critical for the adhesion of MDA-MB-231 cells to THP-1 monocytes. Taken together, our results demonstrate for the first time that LPS up-regulates ICAM-1 expression in breast cancer cells via a MyD88-BLT2-ERK-linked signaling cascade, leading to the increased adhesion of breast cancer cells to monocytes.

• Biomedical Science Letters
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• v.24 no.2
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• pp.134-137
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• 2018

S100A8 and S100A9 are involved in pathogenesis of cancer by induction or inhibition of cancer as well as inflammation. In this study, we investigated the association of S100A8 and S100A9 with pathogenesis of leukemia using human monocytic leukemia cells, THP-1. The expression of TLR4, which is a known receptor of S100A8 and S100A9, was examined by using flow cytometry and Western blotting. THP-1 cells have high surface and cytosol expression of TLR4. S100A8 and S100A9 suppressed the cell survival, and this suppression was found to be associated with apoptosis because they increased the number of apoptotic cells in a dose- and a time-dependent manners. However, S100A8 and S100A9 had no effect on the survival and apoptosis of monocytes isolated from the peripheral blood. We next examined the apoptotic effect of lipopolysaccharide (LPS) and monophosphoryl lipid A (MPLA), which are other ligands of TLR4, in THP-1 cells. Lipopolysaccharide had no effect on cell survival, but MPLA is effective on the cell apoptosis. These results suggest that S100A8 and S100A9 may regulate leukemia cell survival via TLR4, which is an essential receptor in the pro-apoptotic mechanism induced by S100A8 and S100A9. These findings may shed light on development of a possible therapeutic drug for leukemia treatment.

• IMMUNE NETWORK
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• v.10 no.5
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• pp.173-180
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• 2010

Background: APRIL, originally known as a cytokine involved in B cell survival, is now known to regulate the inflammatory activation of macrophages. Although the signal initiated from APRIL has been demonstrated, its role in cellular activation is still not clear due to the presence of BAFF, a closely related member of TNF superfamily, which share same receptors (TACI and BCMA) with APRIL. Methods: Through transfection of siRNA, BAFF-deficient THP-1 cells (human macrophage-like cells) were generated and APRIL-mediated inflammatory activities were tested. The expression patterns of APRIL were also tested in vivo. Results: BAFF-deficient THP-1 cells responded to APRIL-stimulating agents such as monoclonal antibody against APRIL and soluble form of TACI or BCMA. Furthermore, co-incubation of the siBAFF-deficient THP-1 cells with a human B cell line (Ramos) resulted in an activation of THP-1 cells which was dependent on interactions between APRIL and TACI/BCMA. Immunohistochemical analysis of human pathologic samples detected the expression of both APRIL and TACI in macrophage-rich areas. Additionally, human macrophage primary culture expressed APRIL on the cell surface. Conclusion: These observations indicate that APRIL, which is expressed on macrophages in pathologic tissues with chronic inflammation, may mediate activation signals through its interaction with its counterparts via cell-to-cell interaction.

• The Journal of Korean Medicine
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• v.41 no.4
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• pp.12-26
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• 2020

Objectives: The aim of this study is to investigate the mechanisms involved in the anti-inflammatory and anti-tumor effects of Rhus verniciflua Stokes (RVS) on PMA-differentiated human monocytic leukemia THP-1 cells. Methods: Cells were treated with various concentrations of RVS decoction (0-300㎍/ml) for 24, 48, and 72h. Cell viability was evaluated by MTS/PMS assay. The expressions of MMP-2, MMP-9, TIMP-1, TIMP-2, iNOS and COX-2 mRNA and proteins were measured using RT-PCR and western blotting, respectively. Results: RVS suppressed expression of MMP-2 and MMP-9 mRNA. It also down-regulated iNOS and COX-2 mRNA and protein expression. RVS inhibited NF-𝜅B p65 activity and the phosphorylation of Akt and MAPK (ERK and p38 MAPK). Instead, the phosphorylation of JNK is increased at a very low concentration but decreased at higher concentrations. Conclusion: RVS is regarded to inhibit the expression of MMP and TIMP as well as iNOS and COX-2 gene expression via directly inhibiting the activation of NF-𝜅B and phosphorylation of MAPK pathway in THP-1 cells. This suggests RVS have potential to be used as a therapeutic agent for acute myeloid leukemia (AML).

• Journal of Life Science
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• v.30 no.2
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• pp.113-121
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• 2020

Macrophages are initiators for regulating a host's defenses to eliminate pathogens and trigger tissue repair. Macrophages are classified into two types: classically (M1) activated macrophages and alternatively (M2) activated macrophages. M1-phenotype macrophages directly or indirectly kill infectious organisms and tumor cells via pro-inflammatory responses, whereas M2-phenotype macrophages remodel wounded tissue through anti-inflammatory responses. In this paper, we investigated how Phellinus linteus hot water extract passed from Diaion HP-20 resin (PLEP) regulates polarization of M1-like or M2-like macrophages in human THP-1 cells. PLEP did not have cytotoxicity at a high concentration of 300 ㎍/ml. We observed morphological alteration of the THP-1 cells, which are stimulated by PLEP, LPS/INF-γ (M1 stimulators) or IL-4/IL13 (M2 stimulators). PLEP exposure induced morphology contiguous with LPS/INF-γ. qPCR was also performed to determine whether PLEP influences M1 or M2 polarization-related genes. M1-phenotype macrophage-specific genes, such as TNF-α, IL-1β, IL-6, IL-8, CXCL10 and CCR7, were enhanced by PLEP in a dose-dependent manner similar to LPS/INF-γ. Conversely, M2-phenotype-specific genes, such as MRC-1, DC-SIGN, CCL17 and CCL22, were suppressed by PLEP. PLEP also significantly up-regulated secretory inflammation cytokines related to M1 polarization of macrophages, including TNFα, IL-1β and IL-6, which was similar to the gene expression. Further, MAPK and NF-κB signaling were increased by treatment with PLEP, resulting in enhancement of cytokine secretion. PLEP might therefore be used as a promising booster of pro-inflammatory responses through M1 polarization of human THP-1 cells.

• Journal of Haehwa Medicine
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• v.15 no.2
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• pp.135-148
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• 2006

Sophorae Radix (SFR) is known as a therapeutic drug that has been used in Oriental traditional medicine for the treatment of skin and mucosal ulcers, gastrointestinal hemorrhage, diarrhea, inflammation and arrhythmia. In the present study, we examined the effects of the aqueous extract of SFR on anti-inflammation, anti-allergic and anti-oxidant effect in various cell lines; they include mouse lung fibroblast cells (hFCs), human mast cells (HMC-1), human monocytic cells (THP-1), and RAW 264.7 cells. Treatment with SFR extract at a concentration of 250 ${\mu}g$/ml for 24h showed no significant decrease in the survival rate of the hFCs. SFR decreased the mRNA expression of IL-8, TNF-$\alpha$, and IL-6 in HMC-1 cells. SFR extract treatment significantly inhi-bited the protein expression of IL-6 and, IL-8 induced by mite in THP-1 cells and it also did MCP-1 expression. We examined the alternation of histamine release in HMC-1 cells for investigating anti-allergic effect of SFR. Histamine secretion decreased after the treatment with SFR. In addition, SFR extract treatment at a concentration of 10 ${\mu}g$/ml, 100 ${\mu}g$ /ml, and 200 ${\mu}g$/ml lowered the $\beta$-hexosaminidase to 10.3%, 21.7%, and 50.8%, respectively. IC50 of SFR extract in RBL-2H3 cells was 196.85 ${\mu}g$/ml. Both activity of NF-$\kappa$B promoter in RBL-2H3 cells significantly diminished after the dose-dependent treatment of SFR. Therefore, our results indicate that SFR has anti-inflammatory and it may be useful for treating allergic diseases such as atopic dermatitis.