• Toxicological Research
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• v.11 no.1
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• pp.15-21
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• 1995

Several populations of lymphocytes possess receptors for autonomic neurotransmitter, which make lymphocytes susceptible to autonomic stimulation. This study was to evaluate the functional alternation of effector cells of the immune system. Female Balb/C mice, 15-20 g, were injected with MA subcutaneously under various conditions. Mixed lymphocyte reaction (MLR) showed certain T cell subsets were affected by MA. The level of interleukin-2 (IL-2) production was inhibited due to a defect in expression of the IL-2 receptor. In mice injected with 20 mg MA/kg, 1 day before assay, phagocytosis of peritoneal macrophages showed $14.07\pm3%$, which was similar degree to 5 mg MA/kg treatment for 4 consecutive days. Phagocytosis was almost recovered to that of control after 4 day in 20 mg/kg injected mice. Maximum inhibition of plaque forming cell (PFC) occurred when MA was given early, indicating the inductive time point of antibody production was affected. The cortisol level increased in the MA treated group (0.05, 0.20, and $0.08{\mu}g$/dl for control, low, and high dose-MA treated mice, respectively). Based on these results, MA has general suppression effects on the immune systems by functional alteration of effector cells. Considering the increment of serum cortisol levels, MA partially impacts the neuroendocrine system to lead to failure of immune response.

• Korean Journal of Veterinary Service
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• v.44 no.3
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• pp.141-148
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• 2021

The objective of this research was to evaluate the immune response to Salmonella Gallinarum experimentally infected layers fed with Guanosine 5'-monophosphate-chelated calcium and iron feed additives. Hy-Line brown, 34 week-olds layers were assigned to 3 groups; Group 1: basal diet feed, Group 2 (CaFe-GMP): basal diet feed mixed with chelated calcium and iron, and Group 3 (Fe-OCHT): basal diet feed mixed with chitosan for 4 weeks. There were challenged with 1.0×10⁸ CFU/mL of the cultured Salmonella Gallinarum (SG) by oral administration on 28th feeding days. After SG challenge, Flow cytometric profiles showed that the CD4+/CD8+ T lymphocyte activation of Group 2 was much higher than Group 1 and Group 3 (P<0.05). In addition, the levels of interleukin-2 (13.37 mg/dl) and interferon-γ (2.35 mg/dl) in Group 2 were higher than Group 1 and Group 2. Populations of Lactic acid bacteria (3.5×10¹⁰ CFU/g) from cecum was highest observed in group 2. Re-isolation of SG from cecum in group 2 (8×10⁵ CFU/g) was lower than group 1 (1.83×10¹⁰ CFU/g). The result of this study demonstrated that CaFe-GMP feed additive may be one of the potential candidates to control salmonellosis and functional feeds in layers.

• YAKHAK HOEJI
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• v.38 no.6
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• pp.715-720
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• 1994

${\alpha}2-macroglobulin$ $({\alpha}2-M)$ has been shown to have a variety of activities. One of those activities is the suppression of immune response. Characterization of the immunosuppressive factor secreted by a T cell hybridoma showed that ${\alpha}2-M$ was produced and secreted from the T cell hybridoma. ${\alpha}2-M$ was produced abundantly from the T cell hybridoma when cultured as ascites. The isolation and identification of the ${\alpha}2-M$ were studied using affinity chromatography and N-terminal amino acid sequencing. The extended observations were that the ${\alpha}2-M$ produced by the T cell hybridoma suppresses mixed lymphocyte reaction.

• Toxicological Research
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• v.17
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• pp.217-218
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• 2001

In a series of our screening for immunomodulating substances, we isolated prodigiosin from the culture broth qf Serratia marcescens B-1231. This compound inhibited the T cell-mediated immune responses such as concanavalin A-induced proliferation, mixed lymphocyte response, local graft versus host reaction and T-dependent antibody response at nontoxic concentrations. However. prodigiosin did not effect B cell-mediated immune functions such as lipopolysaccharide-induced proliferation and -activated polyclonal antibody production at the same concentrations. Prodigiosin did not cause death in vitro to lymphocytes at effective concentrations (＜100 nM) and also did not show toxicity in vivo to lymphoid organs at effective dos-ages (10 and 30 mg/kg). The pharmacological potencies were comparable to the activities of well-known T-cell specific immunosuppressants such as cyclosporin A. In our continuing study, mechanism of action of PDG is investigated with respect to the effect of PDG on IL-2/IL-2R pathway and transcription factor.

• Journal of Microbiology and Biotechnology
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• v.7 no.1
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• pp.56-61
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• 1997

A strain producing immunosuppressive substances was isolated from a soil in Cheju island. By morphological, cultural, and physiological studies, the strain was identified as Streptomyces lydicus MCY-524. Cultured broth was purified by silica gel, sephadex LH-20 and preparative HPLC and gave two immunosuppressive compounds, MCH-22 and MCH-32. They dramatically suppressed the B cell activation with lipopolysaccharide, T cell activation by mixed lymphocyte response, and primary T-dependent antibody response at a final concentration of 1 ${\mu}g$/ml. They also markedly suppressed the proliferation of lymphocytes induced by lipopolysaccharide, pokeweed mitogen, and concanavaline A at the same concentration. Their suppressive activities, which were comparable to those of cyclosporin A, suggested that they were potent and broad immunotoxic agents on the immune functions of murine lymphocytes.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.3
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• pp.465-479
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• 2020

Objective: This study performed a meta-analysis of published trials to determine the effects of zinc on the immune response and production performance of broilers. Methods: A database was built from published literature regarding the addition of zinc forms or doses and their relation to the immune response and production performance of broilers. Different doses or forms of zinc were identified in the database. The recorded parameters were related to the immune response and production performance. The database contained a total of 323 data points from 41 studies that met the criteria. Then, the data were processed for a meta-analysis using a mixed model methodology. The doses or different forms of zinc were considered fixed effects, different studies were treated as random effects, and p-values were used as the model statistics. Results: An increase in zinc dose increased (p<0.05) pancreas metallothionein (MT) and zinc concentrations in the plasma, tibia and meat, all in quadratic patterns, but linearly decreased (p<0.05) the heterophil/lymphocyte (H/L) ratio. Regarding the different zinc forms, both inorganic and organic zinc increased (p<0.05) the zinc concentrations in the plasma and tibia, the calcium and phosphorus contents in the tibia, and the antioxidant activity of superoxide dismutase in meat as compared to control. An increase in zinc dose increased average daily gain (ADG) and decreased feed conversion ratio (FCR) following a quadratic pattern (p<0.05). Inorganic and organic zinc decreased (p<0.05) FCR and H/L ratio than that of control, but these two forms were similar for these parameters. Conclusion: Zinc addition has a positive impact on immunity and broiler production. Zinc can suppress stress and inhibit the occurrence of lipid peroxidation in broilers, and it can also improve ADG, FCR, and the quality of broiler carcasses.

• Journal of Microbiology and Biotechnology
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• v.29 no.3
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• pp.489-499
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• 2019

Subunit vaccines are safer and more stable than live vaccines although they have the disadvantage of eliciting poor immune response. To develop a subunit vaccine, an effective delivery system targeting the key elements of the protective immune response is a prerequisite. In this study, oxidized carbon nanospheres (OCNs) were used as a subunit vaccine delivery system and tuberculosis (TB) was chosen as a model disease. TB is among the deadliest infectious diseases worldwide and an effective vaccine is urgently needed. The ability of OCNs to deliver recombinant Mycobacterium tuberculosis (Mtb) proteins, Ag85B and HspX, into bone marrow derived macrophages (BMDMs) and dendritic cells (BMDCs) was investigated. For immunization, OCNs were mixed with the two TB antigens as well as the adjuvant monophosphoryl lipid A (MPL). The protective efficacy was analyzed in vaccinated mice by aerosol Mtb challenge with a virulent strain of Mtb and the bacterial burdens were measured. The results showed that OCNs are highly effective in delivering Mtb proteins into the cytosol of BMDMs and BMDCs. Upon immunization, this vaccine formula induced robust Th1 immune response characterized by cytokine profiles from restimulated splenocytes and specific antibody titer. More importantly, enhanced cytotoxic $CD8^+$ T cell activation was observed. However, it did not reduce the bacteria burden in the lung and spleen from the aerosol Mtb challenge. Taken together, OCNs are highly effective in delivering subunit protein vaccine and induce robust Th1 and $CD8^+$ T cell response. This vaccine delivery system is suitable for application in settings where cell-mediated immune response is needed.

• IMMUNE NETWORK
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• v.3 no.4
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• pp.302-309
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• 2003

Background: CTLA4 (CD152), which is expressed on the surface of T cells following activation, has a much higher affinity for B7 molecules comparing to CD28, and is a negative regulator of T cell activation. In contrast to stimulating and agonistic capabilities of monoclonal antibodies specific to CTLA-4, CTLA4Ig fusion protein appears to act as CD28 antagonist and inhibits in vitro and in vivo T cell priming in variety of immunological conditions. We've set out to confirm whether inhibition of the CD28-B7 costimulatory response using a soluble form of human CTLA4Ig fusion protein would lead to persistent inhibition of alloreactive T cell activation. Methods: We have used CHO-$dhfr^-$ cell-line to produce CTLA4Ig fusion protein. After serum free culture of transfected cell line we purified this recombinant molecule by using protein A column. To confirm characterization of fusion protein, we carried out a series of Western blot, SDS-PAGE and silver staining analyses. We have also investigated the efficacy of CTLA4Ig in vitro such as mixed lymphocyte reaction (MLR) & cytotoxic T lymphocyte (CTL) response and in vivo such as experimental autoimmune encephalomyelitis (EAE), graft versus host disease (GVHD) and skin-graft whether this fusion protein could inhibit alloreactive T cell activation and lead to immunosuppression of activated T cell. Results: In vitro assay, CTLA4Ig fusion protein inhibited immune response in T cell-specific manner: 1) Human CTLA4Ig inhibited allogeneic stimulation in murine MLR; 2) CTLA4Ig prevented the specific killing activity of CTL. In vivo assay, human CTLA4Ig revealed the capacities to induce alloantigen-specific hyporesponsiveness in mouse model: 1) GVHD was efficiently blocked by dose-dependent manner; 2) Clinical score of EAE was significantly decreased compared to nomal control; 3) The time of skin-graft rejection was not different between CTLA4Ig treated and control group. Conclusion: Human CTLA4Ig suppress the T cell-mediated immune response and efficiently inhibit the EAE, GVHD in mouse model. The mechanism of T cell suppression by human CTLA4Ig fusion protein may be originated from the suppression of activity of cytotoxic T cell. Human CTLA4Ig could not suppress the rejection in mouse skin-graft, this finding suggests that other mechanism except the suppression of cytotoxic T cell may exist on the suppression of graft rejection.

• The Journal of Korean Medicine
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• v.18 no.2
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• pp.43-57
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• 1997

It was claimed that the herbal medicine with the function of strengthening the body resistance exerts to enhance the immunity. And the medicine with the effect of eliminating the pathogenic factor is stated to inhibit the immune response. To evaluate the the effects of the herbal medicine on the immune response, the mice were administrated with the herbal medicine for 2 weeks. And the responses were analyzed. As the result, water extract of Radix Astragali, Fructus Psoraleae, Cortex Acanthopanacis, Semen Coicis, Herba Ecliptae, Spica Prunellae, and Radix Sophorae increased the ROI production, while Radix Tripterygia inhibited it. Phagocytic activity was increased after administration of Radix Astragal, Fructus Psoraleae, Cortex Acanthopanacis, Herba Ecliptae, Spica Prunellae and Radix Sophorae. NK cell activity was also significantly inhibited by Radix Tripterygia. Administration of Radix Astragali, Fructus Psoraleae, Cortex Acanthopanacis, Herba Ecliptae, Spica Prunellae and Semen Coicis enhanced the antibodies(hemagglutinin and hemolysin) formation and the appearance of rosette forming cells of the spleen, while Radix Sophorae and Radix Tripterygia decreased it. Radix Sophorae and Radix Tripterygia also decreased the allogenic immune response and mixed-lymphocyte reaction. And all the experimental herbs decreased contact hypersensitivity against dinitroflurobenzene. These results show Radix Astragali, Fructus Psoraleae, Spica Prunellae, Cortex Acanthopanacis, Semen Coicis and Herba Ecliptae enhanced innate immunity, humoral and cellular immune responses. However Radix Sophorae and Radix Tripterygia exert imunosuppressive action. Also these results indicate that the medicine with the action of the strengthening the body resistance enhances the immunity. And the the some of drugs belonging to the eliminating the pathogenic factor also increase the immune responses.

• Archives of Pharmacal Research
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• v.28 no.3
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• pp.343-350
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• 2005

Gamma radiation causes suppression of the immune function, and immune properties are related to cytokine production. In the present study, the polysaccharide, Ginsan, purified from an ethanol-insoluble fraction of Ginseng (Panax ginseng C.A. Meyer, Araliaceae) water extract was studied to assess its effects on the immunosuppressive activities of gamma radiation. Gin­san was found to stimulate murine normal splenocytes by inducing the mRNA expressions of Th1 and Th2 type cytokines, and also restore the mRNA expression of IFN-$/gamma$, Th1 cytokine, after its inhibition by whole-body gamma irradiation. Therefore, Ginsan was found to restore the T lymphocytes function that had been suppressed by gamma irradiation in allogenic MLR (mixed lymphocyte reactions). However, Ginsan exhibited no excessive stimulatory effects on the control group. The above results indicated that Ginsan may constitute a new noble agent for the improvement of gamma radiation-induced immunosuppression.