• Journal of Microbiology and Biotechnology
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• v.33 no.3
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• pp.288-298
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• 2023

Host defense peptides are expressed in various immune cells, including phagocytic cells and epithelial cells. These peptides selectively alter innate immune pathways in response to infections by pathogens, such as bacteria, fungi, and viruses, and modify the subsequent adaptive immune environment. Consequently, they play a wide range of roles in both innate and adaptive immune responses. These peptides are of increasing importance due to their broad-spectrum antimicrobial activity and their functions as mediators linking innate and adaptive immune responses. This review focuses on the pleiotropic biological functions and related mechanisms of action of human host defense peptides and discusses their potential clinical applications.

• Animal Bioscience
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• v.34 no.11
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• pp.1839-1848
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• 2021

Objective: The objective of the present study was to investigate the comparative effects of dietary functional nutrients including glutamine (Gln), chromium picolinate (Cr picolinate), vitamin C (Vit C), betaine (Bet), and taurine (Tau) on growth performance, meat quality, immune responses, and stress biomarkers in broiler chickens raised under heat stress conditions. Methods: A total of 420 21-d-old Ross 308 male broiler chickens (initial body weight = 866±61.9 g) were randomly allotted to 1 of 7 treatment groups with 6 replicates. One group was kept under thermoneutral conditions and was fed a basal diet (PC, positive control). Other 6 groups were exposed to a cyclic heat stress condition. One of the 6 groups was fed the basal diet (NC, negative control), whereas 5 other groups were fed the basal diet supplemented with 0.5% Gln, 500 ppb Cr picolinate, 250 mg/kg Vit C, 0.2% Bet, or 1.0% Tau. The diets and water were provided ad libitum for 21 d. Results: Broiler chickens in NC group had decreased (p<0.05) growth performance and immune responses measured based on cutaneous basophil hypersensitivity (CBH), but increased (p<0.05) stress responses measured based on feather corticosterone concentrations and blood heterophil:lymphocyte than those in PC group. However, none of dietary functional nutrients had a positive effect on growth performance of broiler chickens. Dietary supplementation of 250 mg/kg Vit C improved (p<0.05) CBH responses of broiler chickens, but other functional nutrients had no such an improvement in CBH responses. All functional nutrients decreased (p<0.05) stress responses of broiler chickens. Conclusion: Functional nutrients including Gln, Cr picolinate, Vit C, Bet, and Tau at the supplemental levels used in this study decrease stress responses of broiler chickens to a relatively similar extent. However, this reduction in stress responses could not fully ameliorate decreased productive performance of broiler chickens raised under the current heat stress conditions.

• The Journal of Internal Korean Medicine
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• v.24 no.2
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• pp.315-328
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• 2003

This study was performed to investigate the effect of Bunsimgieum on antitumor effect after sarcoma-180 cells transplantation into peritoneal cavity or left groin and immune responses on the depressed immunity induced by methotrexate in mice. The Bunsimgieum extract of 10mg/kg was orally administered 14 days for antitumor effects and 21 days for immune responses. 50% inhibitory concentration($IC_{50}$) of SUN-1, SUN-C4, and SUN-396 cancer cell, mean sunvival days and body weight of tumor bearing mice, and growth of tumor mass for antitumor effect; delayed type hypersentivity, hemagglutinin titer, hemolysis titer, rosette forming cells, natured killer cell activity, lymphocyte transformation, productivity of interleukin-2, and phagocytic activity for their immune responses were measured in ICR mice. Significance in antitumor effect is noted in the enlongation of mean life days and inhibition of tumor growth(p<0.01, respectively). Significance of immune responses is also noted in hemolysis titer, lymphocyte transfumotion, IL-2 productivity, phagocytic activity, and natural killer cell activity at E/T ratio 100:1(p<0.01, respectively). Significant in rosette cell formation was seen at dosage of 20mg/kg(p<0.01). However, Difference of body weight as antitumor effect, delayed type hypersensitivity, and hemagglutinin titer were not shown significantly. According to the above results, it could be suggested that Bunsimgieum has prominent antitumor and immunity enhancing effect.

• IMMUNE NETWORK
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• v.14 no.4
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• pp.182-186
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• 2014

Lymphatic vessels are routes for leukocyte migration and fluid drainage. In addition to their passive roles in migration of leukocytes, increasing evidence indicates their active roles in immune regulation. Tissue inflammation rapidly induces lymphatic endothelial cell proliferation and chemokine production, thereby resulting in lymphangiogenesis. Furthermore, lymphatic endothelial cells induce T cell tolerance through various mechanisms. In this review, we focus on the current knowledge on how inflammatory cytokines affect lymphangiogenesis and the roles of lymphatic vessels in modulating immune responses.

• Journal of Nutrition and Health
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• v.35 no.6
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• pp.635-642
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• 2002

This study was performed to investigate the effects of isoflavone consumption on plasma and liver lipid profiles and immune responses in Sprague-Dawley male rats. Experimental animals fed isoflavone at various doses for 4 weeks (0, 1095, 2190, 4380 isoflavone mg/kg diet). Exposure to isoflavone decreased the food consumption and final body weights of rats without decreasing the relative weights of organs, hemoglobin and hematocrit. And the plasma cholesterol and LDL-cholesterol, liver total lipid, cholesterol and triglyceride concentrations were significantly decreased by isoflavone intakes. The absolute and relative weights of thymus were significantly decreased in groups fed isoflavone than in control. Also splenocyte proliferations with Con A or PHA were decreased according to isoflavone consumption in rats, although there was not significant. These results demonstrate that isoflavone intakes significantly improve lipid profiles in plasma and liver. But the effects of isoflavone intakes on immune responses are needed further experiments.

• Clinical and Experimental Pediatrics
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• v.53 no.12
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• pp.985-988
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• 2010

The innate immune response is the first line of defense against microbial infections. Innate immunity is made up of the surface barrier, cellular immunity and humoral immunity. In newborn, immunologic function and demands are different to adults. Neonatal innate immunity specifically suppresses Th1-type immune responses, and not Th2-type immune responses, which are enhanced. And the impaired response of macrophages is associated with the defective innate immunity in newborn period. Toll-like receptors (TLRs) play a key roles in the detection of invading pathogens and in the induction of innate immune responses. In newborn, the expression of TLRs is age dependent, so preterm has low expression of TLRs. Also, there are defects in signaling pathways downstream of TLRs. As a consequence, the defects of TLRs activity cause the susceptibility to infection in the neonatal period.

• Proceedings of the Materials Research Society of Korea Conference
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• 2009.05a
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• pp.47.1-47.1
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• 2009

Nanostructured biomaterials have increased those potential for utilizing in many medical applications. In this study, benefit of nanotechnology for the response with biological targets will be described in terms of size, effective surface area and surface energy (physical aspect). Also, correlations between physical and biological interactions (greater protein adsorption on nano surface roughness) will be discussed for understanding biocompatibility of nanostructured biomaterials including carbon nanotube composites and nanostructured titanium surfaces. In the application parts, various major tissue cells, such as bone, cartilage, vascular and bladder cell responses will be discussed with suggested nanomaterials. Lastly, immune responses with macrophage (adhesion and several major cytokines) on nanostructured biomaterials will be described for evasive immune response.

• YAKHAK HOEJI
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• v.43 no.5
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• pp.635-641
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• 1999

In this study, we investigated the immunopotent activities of lepidan, a water soluble proteoglycan from Lentinus lepideus. To examine whether lepidan may affect nonspecific immune responses, we determined the effect on the production of nitric oxide (NO). Lepidan effectively increased the NO production in IFN-${\gamma}$ and LPS triggered RAW 264.7 cells. To further demonstrate the evidence that lepidan activates various immune cells, we determined the alkaline phosphatase activity, plaque-forming cell number and secretion of interleukine-4 (IL-4) and granulocyte/macrophage-colony stimulating factor (GM-CSF) after lepidan treatment in murine splenocytes. The results showed that lepidan increased alkaline phosphatase activity and the number of plaque-forming cells, which indicates that lepidan can lead B lymphocytes to late stage of differentiation. Also, when the splenocytes were cultured with lepidan for 48 hr, the level of IL-4 and GM-CSF in the supernatant dramatically increased. Taken together, these data suggest that lepidan is a biological response modulator that is able to activate immune responses.

• Biomolecules & Therapeutics
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• v.17 no.4
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• pp.388-394
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• 2009

The cytokines which is produced by allergen-specific T helper (Th) cells play a pivotal role in the pathogenesis of asthma. Asthma is caused by exaggerated T-helper 2 (Th2)-based immune responses. It is suggested that controlling such Th2-based response is necessary for asthma therapy. The current therapies for asthma focus primarily on control of symptoms and suppression of inflammation, without affecting the underlying cause. So, we examined that anti-asthmatic drugs might have play a certain role in Th2/Th1 balance. Splenocytes isolated from ovalbumin (OVA)-sensitized mice cultured with anti-asthmatic drugs. It is well known that Th2 and Th1 immune responses can balance one another, as Th2 mediators suppress Th1 responses and Th1 mediators similarly inhibit Th2 responses. But salmeterol inhibits both of Th1 and Th2 mediators, which salmeterol is a suppressor of immune responses not only a suppressor of Th2-based immune responses. Aminophylline is a weak suppressor of immune responses. But ipratropium and cromoglycate don't have any suppressor effect to Th2-driven responses. They only have suppressor effect to Th1 immune responses. Salmeterol, ipratropium, aminophylline, and cromoglycate augmented mRNA levels of CRTH2, EP2, and IP2 receptors in OVA-sensitized splenocytes. It is well known that the up-regulation of CRTH2 - $PGD_2$ receptor - results in restraint of eosinophil recruitment and that the increment of IP and EP2 - $PGI_2$ and $PGE_2$ receptor, respectively - may induce the accumulation of cAMP that decrease the effector function of T cells. Moreover salmeterol and cromoglycate increase the mRNA expression of $PGD_2$ synthase. These findings indicate that anti-asthma agents may alleviate the immunological responses that cause the asthmatic diseases.

• BMB Reports
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• v.55 no.10
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• pp.473-480
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• 2022

Neutrophils, the most abundant innate immune cells, play essential roles in the innate immune system. As key innate immune cells, neutrophils detect intrusion of pathogens and initiate immune cascades with their functions; swarming (arresting), cytokine production, degranulation, phagocytosis, and projection of neutrophil extracellular trap. Because of their short lifespan and consumption during immune response, neutrophils need to be generated consistently, and generation of newborn neutrophils (granulopoiesis) should fulfill the environmental/systemic demands for training in cases of infection. Accumulating evidence suggests that neutrophils also play important roles in the regulation of adaptive immunity. Neutrophil-mediated immune responses end with apoptosis of the cells, and proper phagocytosis of the apoptotic body (efferocytosis) is crucial for initial and post resolution by producing tolerogenic innate/adaptive immune cells. However, inflammatory cues can impair these cascades, resulting in systemic immune activation; necrotic/pyroptotic neutrophil bodies can aggravate the excessive inflammation, increasing inflammatory macrophage and dendritic cell activation and subsequent T_H1/T_H17 responses contributing to the regulation of the pathogenesis of autoimmune disease. In this review, we briefly introduce recent studies of neutrophil function as players of immune response.