• IMMUNE NETWORK
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• v.13 no.6
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• pp.227-234
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• 2013

The intestinal immune system has an ability to distinguish between the microbiota and pathogenic bacteria, and then activate pro-inflammatory pathways against pathogens for host defense while remaining unresponsive to the microbiota and dietary antigens. In the intestine, abnormal activation of innate immunity causes development of several inflammatory disorders such as inflammatory bowel diseases (IBD). Thus, activity of innate immunity is finely regulated in the intestine. To date, multiple innate immune cells have been shown to maintain gut homeostasis by preventing inadequate adaptive immune responses in the murine intestine. Additionally, several innate immune subsets, which promote Th1 and Th17 responses and are implicated in the pathogenesis of IBD, have recently been identified in the human intestinal mucosa. The demonstration of both murine and human intestinal innate immune subsets contributing to regulation of adaptive immunity emphasizes the conserved innate immune functions across species and might promote development of the intestinal innate immunity-based clinical therapy.

• Korean Journal of Poultry Science
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• v.26 no.2
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• pp.131-144
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• 1999

Coccidiosis, an intestinal infection caused by intracellular protozoan parasites belonging to several different species of Eimeria seriously impairs the growth and feed utilization of livestock and poultry. Due to complex life cycle of organism and intricate host immune responses to Elmeria, coccidia vaccine development has been difficult. Understanding of basic imunobiology of pertinent host-parasite interactions is necessary for the development of novel control strategy. Although chickens infected with Eimeria spp. produce parasite-specific antibodies in both the circulation and mucosal secretions, antibody mediated responses play a minor role in protection gainst coccidiosis. Rather, increasing evidence show that cell-mediated immunity plays a major role in resistance to coccidiosis. T-lymphocytes appear to respond to coccidiosis both through cytokine production and a direct cytotoxic attack on infected cells. The exact mechanisms by which T-cells eliminate the parasites, however, remain to be investigated. Since it is crucial to understand the intestinal immune system in order to develop an immunological control strategy against any intestinal immune system in order to develop an immunological control strategy against any intestinal diseases, this presentation will summarize our current understanding of the avian intestinal immune system and mucosal immune responses to Eimeria, to provide a conceptual overview of the complex molecular and cellular events involved in intestinal immune responses to enteric pathogens.

• IMMUNE NETWORK
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• v.15 no.1
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• pp.1-8
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• 2015

Innate immune cells survey antigenic materials beneath our body surfaces and provide a front-line response to internal and external danger signals. Dendritic cells (DCs), a subset of innate immune cells, are critical sentinels that perform multiple roles in immune responses, from acting as principal modulators to priming an adaptive immune response through antigen-specific signaling. In the gut, DCs meet exogenous, non-harmful food antigens as well as vast commensal microbes under steady-state conditions. In other instances, they must combat pathogenic microbes to prevent infections. In this review, we focus on the function of intestinal DCs in maintaining intestinal immune homeostasis. Specifically, we describe how intestinal DCs affect IgA production from B cells and influence the generation of unique subsets of T cell.

• IMMUNE NETWORK
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• v.22 no.6
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• pp.46.1-46.25
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• 2022

T-helper-17 (Th17) cells and related IL-17-producing (type17) lymphocytes are abundant at the epithelial barrier. In response to bacterial and fungal infection, the signature cytokines IL-17A/F and IL-22 mediate the antimicrobial immune response and contribute to wound healing of injured tissues. Despite their protective function, type17 lymphocytes are also responsible for various chronic inflammatory disorders, including inflammatory bowel disease (IBD) and colitis associated cancer (CAC). A deeper understanding of type17 regulatory mechanisms could ultimately lead to the discovery of therapeutic strategies for the treatment of chronic inflammatory disorders and the prevention of cancer. In this review, we discuss the current understanding of the development and function of type17 immune cells at the intestinal barrier, focusing on the impact of microbiota-immune interactions on intestinal barrier homeostasis and disease etiology.

• Preventive Nutrition and Food Science
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• v.22 no.2
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• pp.100-106
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• 2017

To elucidate new biological ingredients in cold-brew coffee extracted with cold water, crude polysaccharide (CCP-0) was isolated by ethanol precipitation, and its immune-stimulating activities were assayed. CCP-0 mainly comprised galactose (53.6%), mannose (15.7%), arabinose (11.9%), and uronic acid (12.4%), suggesting that it might exist as a mixture of galactomannan and arabinogalactan. CCP-0 significantly increased cell proliferation on both murine peritoneal macrophages and splenocytes in a dose dependent manner. CCP-0 also significantly augmented nitric oxide and reactive oxygen species production by murine peritoneal macrophages. In addition, macrophages stimulated by CCP-0 enhanced production of various cytokines such as tumor necrosis factor-${\alpha}$, interleukin (IL)-6, and IL-12. In an in vitro assay for intestinal immune-modulating activity, CCP-0 showed higher bone-marrow cell-proliferation activity through Peyer's patch cells at $100{\mu}g/mL$ than the negative control. These results suggest that CCP-0 may potentially enhance macrophage functions and the intestinal immune system.

• IMMUNE NETWORK
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• v.8 no.2
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• pp.46-52
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• 2008

Background: Oral tolerance is defined by the inhibition of immune responsiveness to a protein previously exposed via the oral route. Protein antigens exposed via the oral route can be absorbed through the mucosal surfaces of the gastrointestinal tract and can make physical contact with immune cells residing in the intestinal lamina propria (LP). However, the mechanisms of oral tolerance and immune regulation in the intestines currently remain to be clearly elucidated. Methods: In order to determine the effect of oral protein antigen intake (ovalbumin, OVA) on the intestinal LP, we assessed the expression profile of the T cell receptor and the co-receptors on the cells from the intestines of the tolerant and immune mouse groups. Results: We determined that the proportion of OVA-specific B cells and ${\gamma}{\delta}$ T cells had decreased, but the CD8${\alpha}{\beta}$ and D8${\alpha}{\alpha}$ T cells were increased in the LP from the tolerant group. The proportion of CD8＋ T cells in the spleen did not evidence any significant differences between treatment groups. Conclusion: These results indicate that CD8＋ T cells in the intestinal LP may perform a regulatory role following antigen challenge via the oral route.

• Parasites, Hosts and Diseases
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• v.55 no.6
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• pp.587-599
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• 2017

The immune response against Trichinella spiralis at the intestinal level depends on the $CD4^+$ T cells, which can both suppress or promote the inflammatory response through the synthesis of diverse cytokines. During the intestinal phase, the immune response is mixed (Th1/Th2) with the initial predominance of the Th1 response and the subsequent domination of Th2 response, which favor the development of intestinal pathology. In this context, the glucocorticoids (GC) are the pharmacotherapy for the intestinal inflammatory response in trichinellosis. However, its therapeutic use is limited, since studies have shown that treatment with GC suppresses the host immune system, favoring T. spiralis infection. In the search for novel pharmacological strategies that inhibit the Th1 immune response (proinflammatory) and assist the host against T. spiralis infection, recent studies showed that resiniferatoxin (RTX) had anti-inflammatory activity, which decreased the serum levels of IL-12, $INF-{\gamma}$, $IL-1{\beta}$, $TNF-{\alpha}$, NO, and $PGE_2$, as well the number of eosinophils in the blood, associated with decreased intestinal pathology and muscle parasite burden. These researches demonstrate that RTX is capable to inhibit the production of Th1 cytokines, contributing to the defense against T. spiralis infection, which places it as a new potential drug modulator of the immune response.

• Journal of Animal Science and Technology
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• v.64 no.6
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• pp.1184-1198
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• 2022

In this study, Rubus coreanus (R. coreanus) byproducts with high polyphenol content were fermented with R. coreanus-derived lactic acid bacteria (Lactobacillus plantarum GBL 16 and 17). Then the effect of R. coreanus-derived lactic acid bacteria fermented feed (RC-LAB fermented feed) with probiotics (Bacillus subtills, Aspergillus oryzae, Yeast) as a feed additive for pigs on the composition of intestinal microbes and the regulation of intestinal immune homeostasis was investigated. Seventy-two finishing Berkshire pigs were randomly allotted to four different treatment groups and 18 replicates. RC-LAB fermented feed with probiotics increased the genera Lactobacillus, Streptococcus, Mitsuokella, Prevotella, Bacteroides spp., Roseburia spp., and Faecalibacterium prausnitzii, which are beneficial bacteria of the digestive tract of pigs. Also, RC-LAB fermented feed with probiotics decreased the genera Clostridium, Terrisporobacter, Romboutsia, Kandleria, Megasphaera and Escherichia, which are harmful bacteria. In particular, the relative abundance of the genera Lactobacillus and Streptococcus increased by an average of 8.51% and 4.68% in the treatment groups and the classes Clostridia and genera Escherichia decreased by an average of 27.05% and 2.85% in the treatment groups. In mesenteric lymph nodes (MLN) and spleens, the mRNA expression of transcription factors and cytokines in Th1 and Treg cells increased and the mRNA expression of Th2 and Th17 transcription factors and cytokines decreased, indicating a regulatory effect on intestinal immune homeostasis. RC-LAB fermented feed regulates gut immune homeostasis by influencing the composition of beneficial and detrimental microorganisms in the gut and regulating the balance of Th1/Th2 and Th17/Treg cells.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.5
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• pp.701-707
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• 2012

Immune stress is the loss of immune homeostasis caused by external forces. The purpose of this experiment was to investigate the effects of immune stress on the growth performance, small intestinal enzymes and peristalsis rate, and mRNA expression of nutrient transporters in broiler chickens. Four hundred and thirty-two 1-d-old broilers (Cobb500) were randomly assigned to four groups for treatment; each group included nine cages with 12 birds per cage. Group 1 = no vaccine (NV); Group 2 = conventional vaccine (CV); group 3 = lipopolysaccharide (LPS)+conventional vaccine (LPS); group 4 = cyclophosphamide (CYP)+conventional vaccine (CYP). The results demonstrated that immune stress by LPS and CYP reduced body weight gain (BWG), feed intake (FI), small intestine peristalsis rate and sIgA content in small intestinal digesta (p<0.05). However, the feed conversion ratio (FCR) remained unchanged during the feeding period. LPS and CYP increased intestinal enzyme activity, relative expression of SGLT-1, CaBP-D28k and L-FABP mRNAs (p<0.05). LPS and CYP injection had a negative effect on the growth performance of healthy broiler chickens. The present study demonstrated that NV and CV could improve growth performance while enzyme activity in small intestine and relative expression of nutrient transporter mRNA of NV and CV were decreased in the conditions of a controlled rational feeding environment. It is generally recommended that broilers only need to be vaccinated for the diseases to which they might be exposed.

• Food Science and Biotechnology
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• v.14 no.1
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• pp.147-151
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• 2005

Purified compound with intestinal immune system-modulating properties, GWE-2c, was isolated from methanol extract of Gelidium amansii by sequential procedures with silica gel column, LH-20 Sephadex gel column, and thin-layer chromatographies. In the presence of GWE-2c, strong immunoactivity in Peyers patch cell-mediated bone marrow cells was observed in vitro. In vivo intestinal immune-modulating activity was also enhanced by crude phenolic compound (GWE) of G. amansii in a dose-dependent manner. Investigation of production of several cytokines in Peyer's patch cells upon stimulation with GWE in vivo revealed the levels of granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin (IL)-6 increased. Results suggest that the phenolic compound from G. amansii represents immunopotentiator and biological response modifier at in vitro and in vivo levels.