• Preventive Nutrition and Food Science
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• v.8 no.1
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• pp.29-35
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• 2003

A crude polysaccharide fraction (GU-3) from the roots of Glycyrrhiza uralensis (licorice root), a screened herbal plant used in the preparation of herbal kimchi, enhanced Peyer's patch mediated bone marrow cell proliferation and NK cell-mediated tumor cytotoxicity against Yac-1 cells. GU-3 was further purified by DEAE-Sepharose CL-6B yielding fractions designated as GU-3I, and 3IIa∼3IIe. GU-3IIa is mainly composed of arabinose, galactose and galacturonic acid, and showed the highest bone marrow cell proliferation activity. In addition, GU-3IIb had arabinose, galactose, rhamnose and galacturonic acid as the component sugars with a small quantity of protein; GU-3IIb also enhanced activity of NK cell-mediated tumor cytotoxicity. After these fractions were further fractionated via gel filtration on Sepharose CL-6B or Sephacryl S-300, two immunological active polysaccharides, GU-3IIa-2 and 3IIb-1 were purified from the respective fractions. GU-3IIa-2 mostly contained neutral sugars (75%) such as arabinose and galactose (molar ratio; 1.0 : 0.7) in addition to a considerable amount of galacturonic acid (20%), whereas GU-3IIb-1 was composed of arabinose, galactose, rhamnose and galacturonic acid (molar ratio; 0.3 : 0.5 : 0.1 : 1.0). Methylation analysis indicated that GU-3IIa-2 was composed mainly of terminal, 4- or 5-linked and 3,4- or 3,5-branched arabinose, 3-linked, 4-linked and 3,6-branched galactose, and terminal and 4-linked galacturonic acid whereas GU-3IIb-1 contained various glycosidic linkages such as terminal and 4- or 5-linked arabinose, 2,4-branched rhamnose, terminal and 4-linked galactose, and terminal and 4-galacturonic arid. Single radial gel diffusion indicated that only GU-3IIa-2 strongly reacted with β-D-glucosyl-Yariv antigen. These results suggest that bone marrow cell proliferating activity and enhancement of NK cell-mediated tumor cytotoxicity of GU-3 are caused by polysaccharides containing a pectic arabinogalactan (GU-3IIa-2) and pectic polysaccharide (GU-3IIb-1).

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.9
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• pp.4039-4044
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• 2014

Background: The aim of this study was to investigate the anti-cancer effects and mechanisms of immunochemotherapy of 5-fluorouracil (5-FU) and interleukin-2 (IL-2) on non-small cell lung cancer (NSCLC) A549 cells. Materials and Methods: In order to detect whether 5-FU+IL-2 could effectively inhibit tumor growth in vivo, we established an A549-bearing nude mouse model. The cytotoxicity of natural killer (NK) cells was evaluated using a standard chromium release assay. To evaluate the relevance of NK cells in 5-FU+IL-2-mediated tumor inhibitory effects, we depleted NK cells in A549-bearing mice by injecting anti-asialo-GM-1 antibodies. Effects of 5-FU+IL-2 on the expression and promoter activity of NKG2D ligands (MICA/MICB) in A549 cells in vitro were also assessed. Results: In A549-bearing nude mice, combination therapy significantly inhibited tumor growth in comparison with monotherapy with 5-FU or IL-2 and enhanced the recognition and lysis of tumor cells by NK cells. Further study of mechanisms showed that NK cells played a vital role in the anticancer immune response of 5-FU+IL-2 immunochemotherapy. In addition, the combination therapy synergistically stimulated the expression and promoter activity of MICA/MICB. Conclusions: 5-FU and IL-2 immunochemotherapy significantly inhibited tumor growth and activated NK cytotoxicity in vivo, and these effects were partly impaired after depleting NK cells in tumor-bearing mice. Combination treatment of 5-FU and IL-2 upregulated the expression and the promoter activity of MICA/MICB in A549 cells, which enhanced the recognition of A549 cells by NK cells. All of the data indicated that immunochemotherapy of 5-FU and IL-2 may provide a new treatment option for patients with lung cancer.

• Molecules and Cells
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• v.24 no.1
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• pp.1-8
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• 2007

Natural killer (NK) cells play a crucial role in innate immune system and tumor surveillance. NK cells are derived from $CD34^+$hematopoietic stem cells and undergo differentiation via precursor NK cells in bone marrow (BM) through sequential acquisition of functional surface receptors. During differentiation of NK cells, many factors are involved including cytokines, membrane factors and transcription factors as well as microenvironment of BM. NK cells express their own repertoire of receptors including activating and inhibitory receptors that bind to major histocompatibility complex (MHC) class I or class I-related molecules. The balance between activating and inhibitory receptors determines the function of NK cells to kill targets. Binding of NK cell inhibitory receptors to their MHC class I-ligand renders the target cells to be protected from NK cell-mediated cytotoxicity. Thus, NK cells are able to discriminate self from non-self through MHC class I-binding inhibitory receptor. Using intrinsic properties of NK cells, NK cells are emerging to apply as therapeutic agents against many types of cancers. Recently, NK cell alloactivity has also been exploited in killer cell immunoglobulin-like receptor mismatched haploidentical stem cell transplantation to reduce the rate of relapse and graft versus host disease. In this review, we discuss the basic mechanisms of NK cell differentiation, diversity of NK cell receptors, and clinical applications of NK cells for anti-cancer immunotherapy.

• Korean Journal of Pharmacognosy
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• v.32 no.3 s.126
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• pp.226-232
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• 2001

To explore the possible cancer therapeutic application of "Bo-yang-hwan-oh-tang" (BH), a herbal medicinal recipe used for improvement of blood stasis, we have examined its direct cytotoxicity against tumor cell, and induction of cytotoxic activity of lymphocytes. Water extract of BH alone did not exhibit direct cytotoxicity to Yac-1 target cells even with high concentrations (10 mg/ml). By exposure for 3 days, BH did not induce any nonspecific cytotoxic activity of mouse spleen cells, either, when assessed in a 4 hr $^{51}Cr-release$ assay. However, when BH was added during CD3 stimulation of non-adherent spleen cells, non-specific CTL activity was markedly promoted in a dose dependent manner. In contrast, BH did not alter activated NK cell activity following IL-2 stimulation. These data suggest that BH does not induce but upregulates non-specific CTL effecter function and that activated NK cell does not respond to BH. For elucidation of the mechanism underlying this function of BH, time kinetic study for IL-2 production using ELISA was undertaken. IL-2 production following CD3 stimulation was significantly augmented and higher level of IL-2 is sustained over 3 days in the culture medium by BH treatment. Moreover, addition of exogenous IL-2 during CD3 stimulation resulted in a similar level of cytotoxicity between control and BH-treated culture. These data indicate that the BH-mediated upregulation of non-specific CTL activity is contributed by augmentation of IL-2 production. Our data imply the possible application of BH for combination therapy of cancer with non-specific activator.

• Microbiology and Biotechnology Letters
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• v.35 no.2
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• pp.118-127
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• 2007

Germanium-fortified yeast (GY) is a organic germanium-fortified yeast with potent immune modulating activities including anti-inflammatory effect. Through cell line studies, we observed that GY can modulate the diverse immune activity but little evidence was provided on the mechanism of GY in modulating immune activities in other higher animals. In this study, we investigated the effect of GY on modulation of immune function in mice. GY was administered in normal mice or tumor-bearing mice and then effect of GY on modulation of host immune system was analyzed by using ex vivo isolated macrophages, B cells, NK cells. Admistration of GY in mice induced macrophage activation thereby increased effector function of macrophage such as increased phagocytosis, chemotaxis, adherence, $O_2-release$, NO, $TNF-{\alpha}$ production. In addition, GY administration Increased B lymphocyte activation and plaque forming cells. Furthermore, GY administration increased NK-cell mediated cytotoxicity. Furthermore, GY administration suppressed progression of tumor in mice by increasing $TNF-{\alpha}$ production and effector function of NK cells. Our results showed that GY has a potent immunostimulatory function in vivo mice model. Proper modulation and administration of GY in human could be helpful to maintaining immunological homeostasis by modulating host immune system.

• Food Science and Biotechnology
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• v.14 no.4
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• pp.479-486
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• 2005

Arabinoxylan, a complex polysaccharide in cereal cell walls, has recently received research attention as a biological response modifier. The immunomodulating effect of arabinoxylans from rice bran (AXrb) was studied using a combined process of extrusion and commercial hemicellulase treatment in order to elucidate the augmentation mechanism of cell-mediated immunity in vitro. The cytotoxicity of mouse spleen lymphocytes against YAC-1 tumor cells was significantly enhanced by treatment with AXrb at $10-100\;{\mu}g/mL$. In an attempt to investigate the mechanism by which AXrb enhance NK cytotoxicity, we examined the effect of AXrb on cytokine production by spleen lymphocytes. Culture supernatants of the cells incubated with AXrb were collected and analyzed for IL-2 and IFN-${\gamma}$ synthesis by ELISA. IL-2 and IFN-${\gamma}$ production were increased significantly. These results suggest that AXrb may induce Th1 immune responses. Macrophages play an important role in host defenses against tumors by killing them and producing secretory products, which protect against bacterial, viral infection and malignant cell growth. AXrb were examined for their ability to induce secretory and cellular responses in murine peritoneal macrophages. When macrophages were treated with various concentrations ($10-100\;{\mu}g/mL$) of AXrb, AXrb induced tumoricidal activity, as well as increasing phagocytosis and the production of NO, $H_2O_2$, TNF-${\alpha}$, IL-$1{\beta}$, and IL-6. These results indicate that reactive oxygen species, reactive nitrogen species, and inflammatory cytokines are likely to be the major mediators of tumoricidal activity in AXrb-treated macrophages. Therefore, AXrb may be useful in cancer immunotherapy and it is anticipated that AXrb obtained using extrusion and subsequent enzyme treatment can be used as an ingredient in nutraceuticals and cereal-based functional food.

• Food Science of Animal Resources
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• v.42 no.5
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• pp.903-914
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• 2022

Probiotics are currently considered as one of tools to modulate immune responses under specific clinical conditions. The purpose of this study was to evaluate whether oral administration of three different probiotics (Lactiplantibacillus plantarum CJLP243, CJW55-10, and CJLP475) could evoke a cell-mediated immunity in immunodeficient mice. Before conducting in vivo experiments, we examined the in vitro potency of these probiotics for macrophage activation. After co-culture with these probiotics, bone marrow derived macrophages (BMDMs) produced significant amounts of proinflammatory cytokines including interleukin-6 (IL-6), IL-12, and tumor necrosis factor-α (TNF-α). Levels of inducible nitric oxide synthase (inos) and co-stimulatory molecules (CD80 and CD86) were also upregulated in BMDMs after treatment with some of these probiotics. To establish an immunocompromised animal model, we intraperitoneally injected mice with cyclophosphamide on day 0 and again on day 2. Starting day 3, we orally administered probiotics every day for the last 15 d. After sacrificing experimental mice on day 18, splenocytes were isolated and co-cultured with these probiotics for 3 d to measure levels of several cytokines and immune cell proliferation. Results clearly indicated that the consumption of all three probiotic strains promoted secretion of interferon-γ (IFN-γ), IL-1β, IL-6, IL-12, and TNF-α. NK cell cytotoxicity and proliferation of immune cells were also increased. Taken together, our data strongly suggest that consumption of some probiotics might induce cell-mediated immune responses in immunocompromised mice.

• The Journal of the Korean Society for Microbiology
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• v.17 no.1
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• pp.7-14
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• 1982

A model of induction of neoplasia by viruses has develpoed from experimental studies in animals and in cultured cells and oncogenic transformation of cells is the result of integration of viral genetic information into the cellular DNA. The evidence for these associations was derived primarily from seroepidemiologic investigation. However, data indicating that the relation between HSV-2 and cervical cancer fits the model derived from experimental animal studies are not yet sufficient to draw conclusion with regard to the etiologic role the virus in the development of the neoplasms. In other hand, the K562 tumor cell is highly susceptible target for natural killer cell lysis by the lymphocytes of human and murine periperal blood. The characteristics of this effector cell type has been investigated. A study on natural killer cell mediated cytotoxicity(NKMC) against $^{51}Cr$-K562 as target cell was studed in HSV-2 infected ICR mouse. We have studied for susceptibility of HSV-2 against mouse embryo fibroblast(MEF) cells and NKMC from HSV-2 infected mouse. The results obtained that the mouse embryo fibroblast cells culture, the number and size of the cells were markedly increased and formed a monolayers relatively rapid, and become complete monolayer sheet around 72 hrs. Duration of cytopathic effect on MEF cells was rapid by serial passing of HSV-2. The morphology of the HSV-2 infected cells appear to be mainly round, ovium, spindle form and some of them was forming large giant cells. The NKMC was decrease in mouse with HSV-2 and comparison between effector/target cells ratio as 25:1 and 50:1 respectively, the NKMC was found to be more significantly decreased than normal control we have concluded that the natural killer cell activity of the viral infected mouse was shown as a suppressed during the HSV-2 infection, day 7th and 14th.