• Journal of Life Science
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• v.33 no.3
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• pp.295-303
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• 2023

Immune and metabolic systems are important factors in maintaining homeostasis. Immune response and metabolic regulation are highly associated, so, when the normal metabolism is disturbed, the immune response changed followed the metabolic diseases occur. Likewise, obesity is highly related to immune response. Obesity, which is caused by an imbalance in energy metabolism, is associated with metabolic diseases, such as insulin resistance, type 2 diabetes, fatty liver diseases, atherosclerosis and hypertension. As known, obesity is characterized in chronic low-grade inflammation. In obesity, the microenvironment of immune cells became inflammatory by the unique activation phenotypes of immune cells such as macrophage, natural killer cell, T cell. Also, the immune cells interact each other in cellular or cytokine mechanisms, which intensify the obesity-induced inflammatory response. This phenomenon suggests the possibility of regulating the activation of immune cells as a pharmacological therapeutic strategy for obesity in addition to the common pharmacological treatment of obesity which is aimed at inhibiting enzymes such as pancreatic lipase and α-amylase or inhibiting differentiation of preadipocytes. In this review, we summarize the activation phenotypes of macrophage, natural killer cell and T cell, and their aspects in obesity. We also summarize the pharmacological substances that alleviates obesity by regulating the activation of immune cells.

• BMB Reports
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• v.55 no.2
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• pp.57-64
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• 2022

Autoimmune disease is known to be caused by unregulated self-antigen-specific T cells, causing tissue damage. Although antigen specificity is an important mechanism of the adaptive immune system, antigen non-related T cells have been found in the inflamed tissues in various conditions. Bystander T cell activation refers to the activation of T cells without antigen recognition. During an immune response to a pathogen, bystander activation of self-reactive T cells via inflammatory mediators such as cytokines can trigger autoimmune diseases. Other antigen-specific T cells can also be bystander-activated to induce innate immune response resulting in autoimmune disease pathogenesis along with self-antigen-specific T cells. In this review, we summarize previous studies investigating bystander activation of various T cell types (NKT, γδ T cells, MAIT cells, conventional CD4⁺, and CD8⁺ T cells) and discuss the role of innate-like T cell response in autoimmune diseases. In addition, we also review previous findings of bystander T cell function in infection and cancer. A better understanding of bystander-activated T cells versus antigen-stimulated T cells provides a novel insight to control autoimmune disease pathogenesis.

• Journal of Life Science
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• v.10 no.4
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• pp.362-364
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• 2000

Opuntia ficus-indca(Op) extract has been claimed to have several therapeutic properties in oriental medicine including anti-inflammatory and anti-rheumatoid arthritis effects. Little is known of its effect on the activation of immune cells such as T cells and macrophages. To evaluate the functional effect of Op extract on immune cells, we examined whether Op extract stimulates the proliferation of T cells and the secretion of cytokines including IL-1 beta, IL-6 and tumor necrosis factor-alpha in THP-1 cell lines by RT-PCR. Op extract significantly enhanced the proliferation of T cell clone(D10S). Transcription of cytokines including IL-1 beta, IL-6, and TNF-alpha peaked 6 hrs after exposure to Op extract(100g/ml) in the THP-1 cell line and declined and declined thereafter. In an experiment to test the dose dependency of transcription of cytokines, transcription increased at a dose of 10 g/ml and the maximum expression was obtained at 100 g/ml, 6 hrs after exposure to Op extract. These findings suggest that Op extract is a potent stimulant of immune cells including T cells and macrophages, which acts by stimulating T cell proliferation and upregulating cytokines. These phenomena imply that some edible plants may be beneficial to living animals through the activation of immune functions.

• The Korean Journal of Food And Nutrition
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• v.20 no.2
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• pp.125-133
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• 2007

Ginger(Zingiber officinale Roscoe) has long been used as a food source in Korea, and it is widely used as a dietary condiment throughout the world. The present study focused on the immunomodulative effects of ginger extracts via in vitro experiments. To identify the immune-activation fractions of the plant, we performed the systematic fractionation of ginger with methanol, hexane, chloroform, butanol and water for separation and refining. The results showed that the chloroform fraction had the highest immune cell activation properties. In conclusion, this study suggests that ginger extracts may enhance immune function by regulating the splenocyte proliferation as well as the cytokine production capacity of activated macrophages.

• Journal of Animal Science and Technology
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• v.47 no.1
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• pp.29-38
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• 2005

Effect of dietary brown seaweed(Undaria pinnatifida) levels on the anti-oxidant enzyme system was evaluated in blood of broiler chicks activated innate immune response. Day-old broiler chicks were fed diets containing 0.0(basal), 1.0, 2.0 and 4.0 % of brown seaweed for 4 weeks. The innate immune response was activated by injecting Salmonella typhymurium lipopolysaccharide(LPS) i.p. at 8, 10 and 12 day of age. The activation of innate immune response enhanced(p< 0.01) and the brown seaweed 1.0 and 2.0 % diets reduced(P< 0.05) the superoxide dismutase(SOD) activity in erythrocyte cytosol significantly. The activation of innate immune response elevated significantly the levels of peroxide and the activity of peroxidase in plasma, while the levels of dietary brown seaweed resulted in a significant linear increase in peroxidase activity in plasma of normal bird. Experience of the innate immune response in 4 week-old chicks reduced linearly the plasma level of peroxide with the level of brown seaweed and enhanced the plasma peroxidase activity. Also, the plasma of normal birds fed the brown seaweed showed higher level of peroxide and lower activity of peroxidase. The results indicated that dietary brown seaweed affected SOD and peroxidase activities in blood of broiler chicks during activation of innate immune response.

• Korean Journal of Plant Resources
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• v.33 no.3
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• pp.183-193
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• 2020

Recently, as a natural substance has been emphasized interest in research to enhance the immune function. Green lettuce (Lactuca sativa L.) is a popular vegetable used fresh and it contains various phytochemicals and antioxidant compounds, and has been reported to have various physiological activities such as antibacterial, antioxidant, antitumor and anti-mutagenic. However, only a few studies have investigated on the mechanism of action of immune-enhancing activity of lettuce. Therefore, in this study, the immunomodulatory activities and potential mechanism of action of Green lettuce extracts (GLE) were evaluated in the murine macrophage cell line RAW264.7. GLE significantly increased NO levels by RAW264.7 cells, as well as expressions of immunomodulators such as iNOS, COX-2, IL-1β, IL-6, IL-12, TNF-α and MCP-1. Although GLE activated ERK1/2, p38, JNK and NF-κB, GLE-mediated expressions of immunomodulators was dependent on p38, JNK and NF-κB. In addition, TLR4 inhibition blocked GLE-mediated expressions of immunomodulators and activation of p38, JNK and NF-κB. Taken together, these results demonstrated that TLR4-MAPK/NF-κB signalling pathways participated in GLE-induced macrophage activation and GLE could be developed as a potential immunomodulating functional food.

• Biomedical Science Letters
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• v.29 no.4
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• pp.376-381
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• 2023

Abscopal effect is a form of secondary immune response that occurs in ionizing radiation therapy, resulting in changes in the immune response through activation of immune cells such as macrophages and T lymphocytes. UVB causes DNA damage similar to ionizing radiation and causes similar intracellular reactions, so it is often used as an alternative in research on the effects of ionizing radiation. In a previous study, we found that pro-inflammatory cytokines, including TNF-α, increased in Jurkat T cells exposed to TGs. In this study, we confirmed the effects of UVB irradiation on T lymphocytes exposed to TGs, similar to the effects of ionizing radiation. As a result, it was shown that the mRNA expression of pro-inflammatory cytokines such as IL-1β and IFN-γ in Jurkat T cells exposed to TGs increased by UVB irradiation. In addition, it was confirmed that the increase in the expression of pro-inflammatory cytokines caused by UVB was caused by the activation of iNOS protein. This is very similar to the immune response that occurs when T lymphocytes are exposed to TGs. These results suggest that activation of iNOS protein is involved in the increase in pro-inflammatory cytokines caused by UVB irradiation in T lymphocytes exposed to TGs.

• Toxicological Research
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• v.25 no.4
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• pp.159-173
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• 2009

Nuclear factor erythroid derived 2-related factor-2 (Nrf2) is a master transcription regulator of antioxidant and cytoprotective proteins that mediate cellular defense against oxidative and inflammatory stresses. Disruption of cellular stress response by Nrf2 deficiency causes enhanced susceptibility to infection and related inflammatory diseases as a consequence of exacerbated immune-mediated hypersensitivity and autoimmunity. The cellular defense capacity potentiated by Nrf2 activation appears to balance the population of $CD4^+$ and $CD8^+$ of lymph node cells for proper innate immune responses. Nrf2 can negatively regulate the activation of pro-inflammatory signaling molecules such as p38 MAPK, NF-${\kappa}B$, and AP-1. Nrf2 subsequently functions to inhibit the production of pro-inflammatory mediators including cytokines, chemokines, cell adhesion molecules, matrix metalloproteinases, COX-2 and iNOS. Although not clearly elucidated, the antioxidative function of genes targeted by Nrf2 may cooperatively regulate the innate immune response and also repress the expression of pro-inflammatory mediators.

• BMB Reports
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• v.52 no.7
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• pp.415-423
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• 2019

Signal transducer and activator of transcription 3 (STAT3) is a cytoplasmic transcription factor that regulates cell proliferation, differentiation, apoptosis, angiogenesis, inflammation and immune responses. Aberrant STAT3 activation triggers tumor progression through oncogenic gene expression in numerous human cancers, leading to promote tumor malignancy. On the contrary, STAT3 activation in immune cells cause elevation of immunosuppressive factors. Accumulating evidence suggests that the tumor microenvironment closely interacts with the STAT3 signaling pathway. So, targeting STAT3 may improve tumor progression, and anti-cancer immune response. In this review, we summarized the role of STAT3 in cancer and the tumor microenvironment, and present inhibitors of STAT3 signaling cascades.

• Biomolecules & Therapeutics
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• v.13 no.3
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• pp.174-180
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• 2005

Antigen presenting cells (APCs), dendritic cells (DCs) and macrophages, playa critical role not only in the initiation of immune responses, but also in the induction of immune tolerance. In an effort to regulate immune responses through the modulation of APC function, we searched for and characterized APC function modulators from natural products. Bifidobacterium pseudocatenulatum SPM1204 (SPM1204) isolated from feces of healthy Korean in the age of 20s was used in this experiment. DCs and macrophages were cultured in the presence of supernatants of SPM 1204 and then examined for their activities for the presentation exogenous antigen in association with major histocompatibility complexes (MHC) and macrophage activation. SPM1204 increased class I MHC-restricted presentation of exogenous antigen (cross-presentation) in a DC cell line, DC2.4 cells. The RAW 264.7 cell line was used to test the nonspecific effect of immune reinforcement of SPM1204 as a source of biological regulating modulator for the macrophage activation, include nitric oxide (NO) production and cytokine production. Results showed that the production of NO, tumor necrosis factor (TNF)-$\alpha$, interleukin 1 (IL-1)-$\beta$ and morphological changes in macrophages were largely affected by SPM1204 in a dose-dependent manner. Our results demonstrated that SPM1204 promote cross-presentation of dendritic cells as well as the induction of NO, TNF-$\alpha$ production, and activation of macrophage.