• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제19권2호
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• pp.137-170
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• 2015

In this paper, we propose and analyze three viral infection models with humoral immunity including an eclipse stage of infected cells. The incidence rate of infection is represented by bilinear incidence and saturated incidence in the first and second models, respectively, while it is given by a more general function in the third one. The neutralization rate of viruses is giv0en by bilinear form in the first two models, while it is given by a general function in the third one. For each model, we have derived two threshold parameters, the basic infection reproduction number which determines whether or not a chronic-infection can be established without humoral immunity and the humoral immune response activation number which determines whether or not a chronic-infection can be established with humoral immunity. By constructing suitable Lyapunov functions we have proven the global asymptotic stability of all equilibria of the models. For the third model, we have established a set of conditions on the threshold parameters and on the general functions which are sufficient for the global stability of the equilibria of the model. We have performed some numerical simulations for the third model with specific forms of the incidence and neutralization rates and have shown that the numerical results are consistent with the theoretical results.

• 약학회지
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• 제37권1호
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• pp.9-17
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• 1993

Immune functions of mice bearing Lewis Lung Carcinoma (LLC) were significantly suppressed when evaluated with mitogen responsiveness, IL-2 production and non-specific suppressor activity. Based on these immunosuppressive characteristics of LLC bearing mice, immunomodulating activates of Copolang were investigated in this model. After 15 days of LLC inoculation, Copolang was intraperitoneally administered for 7 consecutive days with doses of 20 or 200 mg/kg. Immune functions were evaluated 3 days after the final administration of Copolang. The results showed that the growth of LLC solid tumor was not inhibited by Copolang. But, mitogens-induced proliferation, IL-2 production and responsiveness to recombinant IL-2 of splenocytes were significantly augmented by the treatment of Copolang. However suppressor cell activity was not affected by Copolang. These results indicate that Copolang expresses potent immunomodulating activates through the augmentations of IL-2 production and responsiveness to recombinant IL-2, which have been generally known to be suppressed in tumor bearing mice, without affecting the growth of tumor.

• 약학회지
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• 제50권4호
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• pp.244-253
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• 2006

Effects of chrysene on immune functions were studied in female BALB/c mice. When mice were treated po with chrysene for 7 consecutive days, the antibody response was suppressed dose-dependently. Chrysene induced the enzyme activities of CYP LA and 2B time- and dose-dependently. In ex vivo lymphocyte proliferation, chrysene inhibited splenocyte proliferation by LPS and Con A. Moreover, the numbers of $CD4^+IL-2^+$ cells were reduced by chrysene. In conclusion, chrysene-induced immunotoxicity might be mediated, at least in part, via IL-2 production, and caused by mechanisms associated with metabolic activation.

• IMMUNE NETWORK
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• 제24권1호
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• pp.4.1-4.19
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• 2024

TNF, a pleiotropic proinflammatory cytokine, is important for protective immunity and immunopathology during Mycobacterium tuberculosis (Mtb) infection, which causes tuberculosis (TB) in humans. TNF is produced primarily by phagocytes in the lungs during the early stages of Mtb infection and performs diverse physiological and pathological functions by binding to its receptors in a context-dependent manner. TNF is essential for granuloma formation, chronic infection prevention, and macrophage recruitment to and activation at the site of infection. In animal models, TNF, in cooperation with chemokines, contributes to the initiation, maintenance, and clearance of mycobacteria in granulomas. Although anti-TNF therapy is effective against immune diseases such as rheumatoid arthritis, it carries the risk of reactivating TB. Furthermore, TNF-associated inflammation contributes to cachexia in patients with TB. This review focuses on the multifaceted role of TNF in the pathogenesis and prevention of TB and underscores the importance of investigating the functions of TNF and its receptors in the establishment of protective immunity against and in the pathology of TB. Such investigations will facilitate the development of therapeutic strategies that target TNF signaling, which makes beneficial and detrimental contributions to the pathogenesis of TB.

• Nutrition Research and Practice
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• 제10권4호
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• pp.418-423
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• 2016

BACKGROUND/OBJECTIVES: Spirulina, a blue-green alga, is widely produced and commercialized as a dietary supplement with bio- and immune-modulatory functions. We have previously shown that spirulina had favorable effects on lipid profiles, immune functions, and antioxidant capacity in healthy Korean elderly. Despite favorable effect of spirulina supplementation, some sub-populations have shown a poor response to supplementation. Obesity is a factor related to poor-response. Therefore, the purpose of this study was to determine the immuno-modulation, antioxidant capacity, and lipid-lowering effect of spirulina in obese and non-obese Korean elderly. SUBJECTS/METHODS: The subjects were 78 elderly aged 60-87 years. In a randomized double blind, placebo-controlled study, subjects were fed either placebo or spirulina daily, at 8 g for 12 weeks. Subjects were divided into the non-obese group and the obese group based on body mass index (BMI) criteria for Asians suggested by the International Obesity Task Force: $BMI<25kg/m^2$ (non-obese) and $BMI{\geq}25kg/m^2$ (obese). RESULTS: In the non-obese group, spirulina supplementation showed a significant lowering effect on plasma concentration of total cholesterol and LDL-cholesterol, a significant increase in interleukin (IL)-2 concentration (P < 0.01) and a significant increment (P < 0.05) in IL-2/IL-6 ratio, and a significant increase in total antioxidant status level and a significant decrease in thiobarbituric acid reactive substances level. However, these effects were not observed in the obese group. CONCLUSION: These results demonstrated that blood lipid lowering and immune and antioxidant improving response for spirulina supplement was affected by obesity in Korean elderly.

• Asian-Australasian Journal of Animal Sciences
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• 제22권3호
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• pp.448-458
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• 2009

It has been well documented from animal and human studies that conjugated linoleic acid (CLA) has numerous beneficial effects on health. In chickens, CLA exerts many effects on performance ranging from egg quality and yolk lipids to meat quality. Although there are several CLA isomers available, not all CLA isomers have the same incorporation rates into egg yolk: cis-9,trans-11 and trans-10,cis-12 CLA isomers are more favorably deposited into egg yolk than other isomers investigated, but of the two isomers, the former has a higher incorporation rate than the latter. CLA alters the amounts and profiles of lipids in plasma, muscles and liver. Furthermore, increased liver weight was reported in chickens fed dietary CLA. As observed in egg yolk, marked reduction in intramuscular lipids as well as increased protein content was observed in different studies, leading to elevation in protein-to-fat ratio. Inconsistency exists for parameters such as body weight gain, feed intake, feed conversion ratio, egg production rate and mortality, depending upon experimental conditions. One setback is that hard-cooked yolks from CLA-consuming hens have higher firmness as refrigeration time and CLA are increased, perhaps owing to alterations in physico-chemistry of yolk. Another is that CLA can be detrimental to hatchability when provided to breeders: eggs from these breeders have impaired development in embryonic and neonatal stages, and have increased and decreased amounts of saturated fatty acids and monounsaturated fatty acids (MUFAs), respectively. Thus, both problems can be fully resolved if dietary sources rich in MUFAs are provided together with CLA. Emerging evidence suggests that CLA exerts a critical impact on stress and immune functions as it can completely nullify some of the adverse effects produced by immune challenges and reduce mortality in a dose-dependent manner. Finally, CLA is a key regulator of genes that may be responsible for lipid metabolism in chickens. CLA down-regulates both expression of the gene encoding stearoyl-CoA desaturase-1 and its protein activity in the chicken liver while up-regulating mRNA of sterol regulatory element-binding protein-l.

• Journal of Ginseng Research
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• 제36권4호
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• pp.383-390
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• 2012

Ginseng has been used as an herbal medicine, widely used in Asian countries, for long time. Recently, beneficial effects for immune functions of Korean red ginseng (KRG) have been reported in adults. This study was performed to investigate the effects of ginseng on immune functions in children after cessation of chemotherapy or stem cell transplantation for advanced cancer. Thirty patients, who were diagnosed and treated for leukemia and solid cancer at the department of pediatrics and adolescence of the Yeungnam University Hospital from June 2004 to June 2009, were enrolled for the study. The study group consisted of 19 patients who received KRG extract (60 mg/kg/d) for 1 yr and 11 patients who did not receive KRG extract were the control group. Blood samples were collected every 6 mo. Immune assays included circulating lymphocyte subpopulation, serum cytokines (IL-2, IL-10, IL-12, TNF-alpha, and IFN-gamma), and total concentrations of serum IgG, IgA, and IgM subclasses. Age at diagnosis ranged from 2 mo to 15 yr (median 5 yr). Nine patients received stem cell transplantation. The cytokines of the KRG treated group were decreasing more rapidly than that of the control group. Lymphocyte subpopulations (T cell, B cell, NK cell, T4, T8, and T4/T8 ratio) and serum immunoglobulin subclasses (IgG, IgA, and IgM) did not show significant differences between the study and the control groups. This study suggests that KRG extract might have a stabilizing effect on the inflammatory cytokines in children with cancer after chemotherapy.

• Biomolecules & Therapeutics
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• 제17권2호
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• pp.168-174
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• 2009

Epilepsy is one of the most common neurological disorders, and topiramate (TPM) is one of the most effective drugs that can render patients seizure-free. The focus of the present study was to evaluate the immunological safety of TPM in a mouse model. We examined the in vitro effect of TPM on immune functions of BV2 microglial cells, RAW 264.7 macrophages, B cells, T cells, and dendritic cells. We also examined the in vivo effect of TPM on mouse immune organs, such as lymph node, spleen, and thymus. When cells were directly treated with TPM at concentrations from 1 to $30{\mu}g/ml$, TPM did not affect nitrite production by BV2 cells and macrophages, proliferation of B cells and T cells, or maturation of dendritic cells. In addition, TPM did not change the weight and cellularity of lymph nodes, spleen, and thymus in vivo at doses from 3 to 100 mg/kg injected i.p. into mice once a day for 4 consecutive days. These data showed that TPM, which is widely used as an anti-epileptic drug, is immunologically safe.

• Fisheries and Aquatic Sciences
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• 제26권2호
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• pp.97-104
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• 2023

CD96 is a membrane-bound receptor discovered in humans in 1992 that is mainly present in natural killer cells and T cells derived from haematopoietic cells and performs immune functions. Based on the sequence of CD96 obtained from red seabream (Pagrus major), phylogenetic analysis with other species, infections of normal fish, Streptococcus iniae and red sea bream iridovirus (RSIV), and expression analysis was conducted using real-time polymerase chain reaction. Phylogenetic analysis showed the highest homology with Sparus aurata, and multiple sequence analysis confirmed the conservation of major domains between different fish species. Normal fish high expression results were confirmed in the head kidney, and spleen, which are the haematopoietic organs of the fish. High expression levels were confirmed in the gills, liver, spleen, and kidney on day three after RSIV infection. After S. iniae infection, high expression was confirmed in the gills and liver on day one, and high expression was confirmed in the spleen from 12 hours. These results show that PmCD96 functions as an immune gene in P. major and is considered a basic research case for CD96 in fish's hematopoietic organ immune system.

• IMMUNE NETWORK
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• 제21권6호
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• pp.42.1-42.20
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• 2021

Eosinophils play critical roles in the maintenance of homeostasis in innate and adaptive immunity. Although primarily known for their roles in parasitic infections and the development of Th2 cell responses, eosinophils also play complex roles in other immune responses ranging from anti-inflammation to defense against viral and bacterial infections. However, the contributions of pattern recognition receptors in general, and NOD-like receptors (NLRs) in particular, to eosinophil involvement in these immune responses remain relatively underappreciated. Our in vivo studies demonstrated that NLRC4 deficient mice had a decreased number of eosinophils and impaired Th2 responses after induction of an allergic airway disease model. Our in vitro data, utilizing human eosinophilic EoL-1 cells, suggested that TLR2 induction markedly induced pro-inflammatory responses and inflammasome forming NLRC4 and NLRP3. Moreover, activation by their specific ligands resulted in caspase-1 cleavage and mature IL-1β secretion. Interestingly, Th2 responses such as secretion of IL-5 and IL-13 decreased after transfection of EoL-1 cells with short interfering RNAs targeting human NLRC4. Specific induction of NLRC4 with PAM3CSK4 and flagellin upregulated the expression of IL-5 receptor and expression of Fc epsilon receptors (FcεR1α, FcεR2). Strikingly, activation of the NLRC4 inflammasome also promoted expression of the costimulatory receptor CD80 as well as expression of immunoregulatory receptors PD-L1 and Siglec-8. Concomitant with NLRC4 upregulation, we found an increase in expression and activation of matrix metalloproteinase (MMP)-9, but not MMP-2. Collectively, our results present new potential roles of NLRC4 in mediating a variety of eosinopilic functions.