• Parasites, Hosts and Diseases
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• v.28 no.2
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• pp.91-100
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• 1990

Paragonimus westermani is a tissue migrating parasite in the early stage until arriving at lung, and most of the parasites spend their life spans there. Considerable immune responses including activation of macrophages are taken place during the residence of parasites in the host. However, concerning the immunologic defense mechanisms of the host against this parasite, only a few document is available so far. In this study, the cytotoxic effect of peritoneal macrophages under the presence of antibody and/or complement against metacercariae of F. westermani was investigated in vitro. Metacercarlae were collected from the crayfish, Cambaroides similis and hatched out in Tyrode solution (pH 7.4). Plastic adherent cells from normal or infected rat (Wistar) peritoneal exudates were used as experimental macrophages. Polyclonal antibodies were obtained from infected rats and a cat. Cat IgG was fractioned with ion exchange chromatography. Fresh rabbit complement was used according to experimental scheme. Various combinations of peritoneal macrophages, normal or infected rat serum, complement and cat IgG were incubated at $36^{\circ}C$ in 5% $CO_2$ incubator for 6, 14, 24 and 48 hours. The results obtained were as follows: 1. P. westermani infection activated peritoneal macrophages non-specifically and this activation induced increases of cell adherence and cytotoxicity on metacercariae. 2. In the presence of infected rat serum the antibody.dependent cell-mediated cytotoxicity of peritoneal macrophages on metacercariae was significantly increased and showed a peak at 6-hour incubation. But the cytotoxic effect was markedly reduced after inactivation of complement and heat.labile IgE antibody by the heating of infected serum at 56$^{\circ}C$ for 30 minutes. 3. The highest cytotoxic effect (100%) of concomitant incubation with IgG and complement showed 24 hours after incubation, although cell adherence was relatively low at 6-hour incubation and 0% at 24-hour incubation. 4. Coordinative functions of complement with serum and IgG were effective in cell adherence and in cytotoxicity, but it is not clear the independent role of complement on the macrophage- mediated cytotoxicity in this study- With these results it is assumed that P. westermani infection can induce the non-specific activation of peritoneal macrophages, and strum antibodies including IgE antibody might enhance the cytotoxicity by macrophages,

• Animal cells and systems
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• v.8 no.2
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• pp.125-133
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• 2004

We have extended our previous work that cross-linking CD4 molecules using specific MAb induced antigen nonspecific, MHC unrestricted killing of virally infected target cells by CD$4^+$We have extended our previous work that cross-linking CD$4^+$ molecules using specific MAb induced antigen nonspecific, MHC unrestricted killing of virally infected target cells by CD$4^+$ T cells. The killing activity of antibody activated CD$4^+$T cells was completely blocked by herbimycin A, a protein tyrosine kinase (PTK) inhibitor, but not by bisindolylamaleimide, a protein kinase C (PKC) inhibitor. Herbimycin A treated human or bovine peripheral blood CD$4^+$T cells lacked PTK activity and failed to kill virally infected target cells even after cross-linking of CD4 molecules. The CD$4^+$cross-linking failed to induce effector cell proliferation or the transcription of TNF${\beta}$ Upregulation of TNF${\beta}$ was induced by incubating the antibody activated effector cells with BHV-1 infected D17 target cells for 10 h. Anti-TNF${\beta}$ antibody partially abolished (13-44%) the direct effector cell-mediated antiviral cytotoxicity. However, this antibody neutralized 70 to 100% of antiviral activity of effector and target cell culture supernatants against BHV-1 infected D17 cells. The inhibition level of the antiviral activity by the antibody was dependent on the effector and target cell ratio. These results support the hypothesis that increased p$56^ICK enzyme activity in effector cells transduces a signal critical for effector cell recognition of viral glycoproteins expressed on the target cells. Following target cell recognition, lytic cytokines known to participate in target cell killing were produced. A better understanding of the killing activity displayed by CD$4^+$T lymphocytes following surface receptor cross-linking will provide insight into the mechanisms of cytotoxic activity directed toward virally-infected cells.T cells. The killing activity of antibody activated CD$4^+$T cells was completely blocked by herbimycin A, a protein tyrosine kinase (PTK) inhibitor, but not by bisindolylamaleimide, a protein kinase C (PKC) inhibitor. Herbimycin A treated human or bovine peripheral blood CD4T cells lacked PTK activity and failed to kill virally infected target cells even after cross-linking of CD4molecules. The CD4 cross-linking failed to induce effector cell proliferation or the transcription of TNF$\beta$. Upregulation of TNF$\beta$ was induced by incubating the antibody activated effector cells with BHV-1 infected D17 target cells for 10 h. Anti-TNF$\beta$ antibody partially abolished (13-44%) the direct effector cell-mediated antiviral cytotoxicity. However, this antibody neutralized 70 to 100% of antiviral activity of effector and target cell culture supernatants against BHV-1 infected D17 cells. The inhibition level of the antiviral activity by the antibody was dependent on the effector and target cell ratio. These results support the hypothesis that increased $56^ICK enzyme activity in effector cells transduces a signal critical for effector cell recognition of viral glycoproteins expressed on the target cells. Following target cell recognition, lytic cytokines known to participate in target cell killing were produced. A better understanding of the killing activity displayed by CD$4^+$T lymphocytes following surface receptor cross-linking will provide insight into the mechanisms of cytotoxic activity directed toward virally-infected cells.

• Parasites, Hosts and Diseases
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• v.29 no.1
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• pp.43-54
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• 1991

An in vitro immune effector mechanism against the target encysted metacercariae of Paragonimus westermani was demonstrated in the rat system. Peritoneal exudate cells, mainly macrophages from normal rats, showed adherence to and killing of encysted metacercariae of p. westermani in the presence of complement-independent serum from rats infected with Paragonimus metacercariae. These reactions were specific for the excysted metacercariae, as tissue-migrating juvenile worms were not affected. Damage of encysted metacercariae of p. westermani due to antibody and macrophages was assessed by morphological observation, by cell adherence reaction and by the use of vital dyes. frypan blue dye exclusion proved to be a reliable indicator of judging metacercarial viability. Electron microscopic studies demonstrated that macrophages reacted with fusty material on the tegumental surface and fine structures in the syncytium of the parasites. The tubular tunnels formed between the basement membrane and muscle layers of the damaged parasites were also noticeable. The relevance of these findings to cellular immunity in the early paragonimiasis was discussed.

• BMB Reports
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• v.31 no.4
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• pp.355-363
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• 1998

MHC unrestricted, antigen nonspecific killing by $CD4^+$ T-cells against virally-infected target cells was induced following cross-linking of CD4 molecules. The cytotoxicity of antibody-activated $CD4^+$ T-cells was abolished by genistein (4',5,7-trihydroxyisoflavone), a protein tyrosine kinase (PTK) inhibitor, but not by H-7, a protein kinase C (PKC) inhibitor. Genisteintreated human or bovine peripheral blood $CD4^+$ T-cells lacked PTK activity and failed to kill virally-infected target cells even after cross-linking of CD4 molecules. The cross-linking of CD4 molecules did not induce effector cell proliferation or the transcription of TNF ${\beta}$. TNF ${\beta}$ synthesis was up-regulated by incubating antibody activated effector cells with bovine herpesvirus type 1 (BHV-1) infected D17 target cells. Anti-TNF ${\beta}$ antibody partially abrogated direct effector cell-mediated antiviral cytotoxicity. On the other hand, this antibody effectively neutralized antiviral activity of effector and target cell culture supernatants against BHV-1 infected D17 cells. The inhibition level of the antiviral activity by the antibody was dependent on effector and target cell ratio. These findings have importance to define the mechanisms of how CD4 cytotoxic cells control viral infection.

• Toxicological Research
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• v.18 no.2
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• pp.183-190
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• 2002

The mechanism by which catechin-mediated cytotoxicity against tumor cells remains to be elusive. To elucidate the mechanical mights of anti-tumor effects, (-)epigallocatechin-gallate (EGCG) of catechin was applied to human prostate cancer DU 145 cells. Cell viability was measured by crystal violet staining. Cell lysates were wed to measure the catalytic activity of caspases by using fluorogenic peptide: Ac-DEVD-AMC for caspase-3 protease, Z-IETD-AFC for caspase-8 protease, Ac-LEHD-AFC for caspase-9 protease as substrates. The equal amounts of protein from cell lysate was separated on SDS-PAGE and analyzed by western blotting with anti-Fas antibody, anti-FasL antibody, anti-BCL2 antibody and anti-Bax antibody. (-)EGCG induced the death of DUl45 cells, which was revealed as apoptosis shown by DNA fragmentation. (-)EGCG induced the activation of caspase family cysteine proteases including caspase-3, -8 and -9 proteases in DU145 cells. Also, (-)EGCG increased the expression of Fas and Fas ligand (FasL) protein in DU145 colls. The expression level of BCL2 was decreased in (-)EGCG treated DU145 cells, whereas Bax protein was increased in a time-dependent manner. We suggest that (-)EGCG-induced apoptosis of DU145 cells is mediated by signaling pathway involving caspase family cysteine protease, mitochondrial BCL2-family protein and Fas/FasL.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.8
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• pp.4037-4043
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• 2012

Despite progress in elucidating mechanisms associated with colorectal cancer and improvement of treatment methods, it remains a frequent cause of death worldwide. New and more effective therapies are therefore urgently needed. Recent studies have shown that immunogenicity of whole ovarian tumor cells and subsequent T cell response were potentiated by oxidation modification with hypochlorous acid (HOCl) in vitro and ex vivo. These results prompted us to investigate the protective antitumor response with an HOCl treated CT26 colorectal cancer cell vaccine in an in vivo mouse model. Administration of HOCl modified vaccine triggered robust antitumor immunity to autologous tumor cells in mice and prolonged survival period significantly. In addition, increased necrosis and apoptosis were found in tumor tissue from the oxidation group. Interestingly, ELISPOT assays showed that specific T cell responses were not elicited in response to the immunizing cellular antigen, in contrast to raising sera antibody titer and antibody binding activity shown by ELISA assay and flow cytometry. Further evaluation of the mechanisms underlying HOCl modified vaccine mediated humoral immunity highlighted the role of antibody-dependent cell-mediated cytotoxicity. These results combined with previous studies suggest that HOCl oxidation modified whole cell vaccine has wide applicability as a cancer vaccine because it can target both T cell- and B cell-specific responses. It may thus represent a promising approach for the immunotherapy of colorectal cancer.

• Korean Journal of Transplantation
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• v.32 no.4
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• pp.108-112
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• 2018

Antibody-mediated rejection (AMR) is a major complication after ABO-incompatible liver transplantation. According to the 2016 Banff Working Group on Liver Allograft Criteria for the diagnosis of acute AMR, a positive serum donor specific antibody (DSA) is needed. On the other hand, the clinical significance of the histological findings of AMR in the absence of DSA is unclear. This paper describes a 57-year-old man (blood type, O+) who suffered from hepatitis B virus cirrhosis with hepatocellular carcinoma. Pre-operative DSA and cross-matching were negative. After transplantation, despite the improvement of the liver function, acute AMR was observed in the protocol biopsy on postoperative day 7; the cluster of differentiation 19+ (CD19+) count was 0% and anti-ABO antibody titers were 1:2. This paper presents the allograft injury like AMR in the absence of DSA after ABOi living donor liver transplantation with low titers of anti-ABO antibody and depleted serum CD19+ B cells.

• YAKHAK HOEJI
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• v.35 no.3
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• pp.154-164
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• 1991

These experiments were conducted to investigate the effects of Glycyrrhizae Radix extract(GR) on histamine synthesis, lymphocyte blastogenesis in C57BL/6J mice splenocytes, IL-1 production, $Ca^{2+}$ uptake by macrophage-like P388D$_{1}$ cells and plaque forming cell assay against SRBC. Histamine contents, lymphocyte blastogenesis, IL-1 activity, $Ca^{2+}$ uptake and plaque forming cell were determined by enzyme isotope method, [$^{3}$H]-thymidine incorporation, C3H/HeJ mouse thymocytes proliferation, the addition of 5 $\mu$Ci/ml $^{45}Ca^{2+}$ to P388D$_{1}$ cell suspension and assay to sheep red blood cell, respectively. Cytotoxicity, which was expressed as 50% mortality, was occurred by the addition of GR(10$^{-3}$g/ml). Histamine production in mouse spleen cell culture was significantly increased by 48 hour incubation added 0.25$\mu\textrm{g}$/ml of Con A. Con A-dependent T-lymphocyte proliferation was also enhanced by the addition of 0.25 $\mu\textrm{g}$/ml of Con A. GR depressed histamine contents at 10$^{-9}$~10$^{-4}$g/ml. and Con A (0.25 $\mu\textrm{g}$/ml) dependent T-lymphocyte proliferation at 10$^{-5}$~10$^{-4}$g/ml. IL-1 activity was significantly decreased by 10$^{-8}$~10$^{-4}$g/ml of GR. $Ca^{2+}$ uptake was not changed by GR, but antibody production markedly increased at 10.0~50.0 mg/kg of GR. From the above results, it is suggested that GR have immuno-regulatory action; GR decreased cell-mediated immune response and increased antibody production by B lymphocyte at high doses.

• YAKHAK HOEJI
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• v.35 no.3
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• pp.174-181
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• 1991

These experiments were conducted to investigate the effects of glycyrrhizin(GL) and glycyrrhetinic acid(GA) on histamine synthesis, lymphocyte blastogenesis in C57BL/6J mice splenocytes, IL-1 production, $Ca^{2+}$ uptake by macrophage-like P388D$_{1}$ cells and plaque forming cell assay against SRBC. Histamine contents, lymphocyte blastogenesis, IL-1 activity, $Ca^{2+}$ uptake and plaque forming cell were determined by enzyme isotope method, [sup 3/H]-thymidine incorporation, C3H/HeJ mouse thymocytes proliferation, the addition of 5 $\mu$Ci/ml $^{45}$Ca$^{2+}$ to P388D$_{1}$, cell suspension and assay to sheep red blood cell, respectively. Cytotoxicity, which was expressed as 50% mortality, was occurred by the addition of GL(10$^{-3}$M) and GA(10$^{-4}$M). Histamine production in mouse spleen cell culture was significantly increased by the addition of 0.25 $\mu\textrm{g}$/ml of Con A, after 48 hour incubation. Con A dependent T-lymphocyte proliferation was also enhanced by the addition of 0.25 .mu.g/ml of Con A. The effects of GL on histamine contents and T-lymphocyte proliferation were significantly decreased at high dose (10$^{-5}$M), while IL-1 activity was remarkably suppressed by 10$^{-8}$~10$^{-4}$M of GL. $Ca^{2+}$ uptake was not changed, but antibody production was increased by GL(10 mg/kg). GA inhibited histamine contents at 10$^{-9}$~10$^{-7}$ and depressed Con A (0.25 $\mu\textrm{g}$/ml) dependent T-lymphocyte proliferation at 10$^{-7}$~10$^{-5}$M of GA, but increased suboptimal dose (Con A 0.1 $\mu\textrm{g}$/ml) at 10$^{-9}$~10$^{-7}$M of GA. IL-1 activity was suppressed by 10$^{-8}$~10$^{-4}$M of GA and $Ca^{2+}$ uptake was enhanced by 10$^{-9}$~10$^{-6}$ of GA, but antibody production was not changed by GA. From the above results, it is suggested that GL and GA have immuno-regulatory action. GL decreased cell-mediated immune response, and increased humoral immune response at high dose. On the other hand, low dose of GA enhanced cell-mediated immune response, while high doses of GA decreased humoral immune reaction.

• Korean Journal of Clinical Laboratory Science
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• v.38 no.2
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• pp.82-86
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• 2006

Leukemia arises in hematopoietic progenitor cells and is characterized by impaired or blocked differentiation, uncontrolled proliferation and resistance to apoptosis. Molecular mechanisms underlying cellular functions by $As_2O_3$, however, have been poorly investigated. The consensus of several reports is that $As_2O_3$ induces apoptosis in leukemia cells by activating genes for apoptosis. The present study aimed to investigate the effects of $As_2O_3$ on the cell cycle and its morphological change and a relationship between the caspase-3 and $As_2O_3$-induced apoptosis. Caspase-3 is involved in $As_2O_3$-induced apoptosis in K562 cells. In this study, to address whether $As_2O_3$-induced apoptosis is mediated by caspase-3 activity, the same samples were probed with a specific antibody. The pretreatment of $25{\mu}M$ Z-VAD-fmk, a specific inhibitor of caspase, decreased $As_2O_3$-induced cytotoxicity. And $As_2O_3$ significantly increased the percentages of the cells accumulated in the G2/M phase of the cell cycle in a time- and dose-dependent manner. Chromatin condensational changes were observed with Hoechst 33258 staining after treatment of $As_2O_3$. It was shown that $As_2O_3$-induced apoptosis is controlled through caspase-3 activation. These results may provide a useful rationale for CML treatment.