• IMMUNE NETWORK
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• v.11 no.1
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• pp.11-41
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• 2011

The discovery of microRNA (miRNA) is one of the major scientific breakthroughs in recent years and has revolutionized current cell biology and medical science. miRNAs are small (19~25nt) noncoding RNA molecules that post-transcriptionally regulate gene expression by targeting the 3' untranslated region (3'UTR) of specific messenger RNAs (mRNAs) for degradation of translation repression. Genetic ablation of the miRNA machinery, as well as loss or degradation of certain individual miRNAs, severely compromises immune development and response, and can lead to immune disorders. Several sophisticated regulatory mechanisms are used to maintain immune homeostasis. Regulatory T (Treg) cells are essential for maintaining peripheral tolerance, preventing autoimmune diseases and limiting chronic inflammatory diseases. Recent publications have provided compelling evidence that miRNAs are highly expressed in Treg cells, that the expression of Foxp3 is controlled by miRNAs and that a range of miRNAs are involved in the regulation of immunity. A large number of studies have reported links between alterations of miRNA homeostasis and pathological conditions such as cancer, cardiovascular disease and diabetes, as well as psychiatric and neurological diseases. Although it is still unclear how miRNA controls Treg cell development and function, recent studies certainly indicate that this topic will be the subject of further research. The specific circulating miRNA species may also be useful for the diagnosis, classification, prognosis of diseases and prediction of the therapeutic response. An explosive literature has focussed on the role of miRNA. In this review, I briefly summarize the current studies about the role of miRNAs in Treg cells and in the regulation of the innate and adaptive immune response. I also review the explosive current studies about clinical application of miRNA.

• Biomolecules & Therapeutics
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• v.23 no.4
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• pp.345-349
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• 2015

Betulinic acid, a pentacyclic triterpene isolated from Jujube tree (Zizyphus jujuba Mill), has been known for a wide range of biological and medicinal properties such as antibacterial, antimalarial, anti-inflammatory, antihelmintic, antinociceptive, and anticancer activities. In the study, we investigated the antiviral activity on influenza A/PR/8 virus infected A549 human lung adenocarcinoma epithelial cell line and C57BL/6 mice. Betulinic acid showed the anti-influenza viral activity at a concentration of $50{\mu}M$ without a significant cytotoxicity in influenza A/PR/8 virus infected A549 cells. Also, betulinic acid significantly attenuated pulmonary pathology including increased necrosis, numbers of inflammatory cells and pulmonary edema induced by influenza A/PR/8 virus infection compared with vehicle- or oseltamivir-treated mice in vivo model. The down-regulation of IFN-${\gamma}$ level, which is critical for innate and adaptive immunity in viral infection, after treating of betulinic acid in mouse lung. Based on the obtained results, it is suggested that betulinic acid can be the potential therapeutic agent for virus infection via anti-inflammatory activity.

• Journal of Microbiology and Biotechnology
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• v.32 no.5
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• pp.612-620
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• 2022

Recent studies have revealed that probiotics and their metabolites are present under various conditions; however, the role of probiotic metabolites (i.e., postbiotics in pathological states) is controversial. Natural killer (NK) cells play a key role in innate and adaptive immunity. In this study, we examined NK cell activation influenced by a postbiotics mixture in response to gut microbiome modulation in stress-induced mice. In vivo activation of NK cells increased in the postbiotics mixture treatment group in accordance with Th1/Th2 expression level. Meanwhile, the Red Ginseng treatment group, a reference group, showed very little expression of NK cell activation. Moreover, the postbiotics mixture treatment group in particular changed the gut microbiome composition. Although the exact role of the postbiotics mixture in regulating the immune system of stress-induced mice remains unclear, the postbiotics mixture-induced NK cell activation might have affected gut microbiome modulation.

• IMMUNE NETWORK
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• v.21 no.6
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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.

• IMMUNE NETWORK
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• v.20 no.1
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• pp.5.1-5.15
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• 2020

The γδ T cells are unconventional lymphocytes that function in both innate and adaptive immune responses against various intracellular and infectious stresses. The γδ T cells can be exploited as cancer-killing effector cells since γδ TCRs recognize MHC-like molecules and growth factor receptors that are upregulated in cancer cells, and γδ T cells can differentiate into cytotoxic effector cells. However, γδ T cells may also promote tumor progression by secreting IL-17 or other cytokines. Therefore, it is essential to understand how the differentiation and homeostasis of γδ T cells are regulated and whether distinct γδ T cell subsets have different functions. Human γδ T cells are classified into Vδ2 and non-Vδ2 γδ T cells. The majority of Vδ2 γδ T cells are Vγ9δ2 T cells that recognize pyrophosphorylated isoprenoids generated by the dysregulated mevalonate pathway. In contrast, Vδ1 T cells expand from initially diverse TCR repertoire in patients with infectious diseases and cancers. The ligands of Vδ1 T cells are diverse and include the growth factor receptors such as endothelial protein C receptor. Both Vδ1 and Vδ2 γδ T cells are implicated to have immunotherapeutic potentials for cancers, but the detailed elucidation of the distinct characteristics of 2 populations will be required to enhance the immunotherapeutic potential of γδ T cells. Here, we summarize recent progress regarding cancer immunology of human γδ T cells, including their development, heterogeneity, and plasticity, the putative mechanisms underlying ligand recognition and activation, and their dual effects on tumor progression in the tumor microenvironment.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.36 no.6
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• pp.481-489
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• 2010

Introduction: TLR-5, a member of the toll-like receptor (TLR) family, is a element of the type I transmembrane receptors, which are characterized by an intracellular signaling domain homolog to the interleukin-1 receptor. These receptors recognize microbial components, particularly bacterial flagellin. All-trans retinoic acid (atRA, tretinoin), a natural metabolite of vitamin A, acts as a growth and differentiation factor in many tissues, and is also needed for immune functions. In this study, THP-1 human macrophage-monocytes were used to examine the mechanisms by which atRA regulated the expression of TLR-5. Because the molecular mechanism underlying this regulation at the transcriptional level is also unclear, this study examined which putative transcription factors are responsible for TLR-5 expression by atRA in immune cells. Materials and Methods: This study examined whether atRA induces the expression of TLR-5 in THP-1 cells using reverse transcription-polymerase chain reaction (RT-PCR), and which transcription factors are involved in regulating the TLR-5 promoter in RAW264.7 cells using a reporter assay system. Western blot analysis was used to determine which signal pathway is involved in the expression of TLR-5 in atRA-treated THP-1 cells. Results: atRA at a concentration of 10 nM greatly induced the expression of TLR-5 in THP-1 cells. Human TLR-5 promoter contains three Sp-1/GC binding sites around -50 bp and two NF-kB binding sites at -380 bp and -160 bp from the transcriptional start site of the TLR-5 gene. Sp-1/GC is primarily responsible for the constitutive TLR-5 expression, and may also contribute to NF-kB at -160 bp to induce TLR-5 after atRA stimulation in THP-1 cells. The role of NF-kB in TLR-5 expression was further confirmed by inhibitor pyrrolidine dithiocarbamate (PDTC) experiments, which greatly reduced the TLR-5 transcription by 70-80%. Conclusion: atRA induces the expression of the human TLR-5 gene and NF-kB is a critical transcription factor for the atRA-induced expression of TLR-5. Accordingly, it is conceivable that retinoids are required for adequate innate and adaptive immune responses to agents of infectious diseases. atRA and various synthetic retinoids have been used therapeutically in human diseases, such as leukemia and other cancers due to the antiproliferative and apoptosis inducing effects of retinoids. Therefore, understanding the molecular regulatory mechanism of TLR-5 may assist in the design of alternative strategies for the treatment of infectious diseases, leukemia and cancers.

• IMMUNE NETWORK
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• v.5 no.4
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• pp.205-214
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• 2005

Background: We examined global gene expression profiles of peripheral blood mononuclear cells (PBMCs) in patients with ulcerative colitis (DC), and tested whether the identified genes with the altered expression might be associated with susceptibility to UC. Methods: PBMCs from 8 UC and 8 normal healthy (NH) volunteers were collected, and total RNAs were subjected to the human 8.0K cDNA chip for the micro array analysis. Real time-PCR (RT-PCR) was performed to verify the results of micro array. One hundred forty UC patients and 300 NH controls were recruited for single nucleotide polymorphism (SNP) analysis. Results: Twenty-five immune function-related genes with over 2-fold expression were identified. Of these genes, two chemokines, namely, CXCL1 and CCL20, were selected because of their potential importance in the evocation of host innate and adaptive immunity. Four SNPs were identified in the promoter and coding regions of CXCL1, while there was no significant difference between all patients with UC and controls in their polymorphisms, except minor association at g.57A>G (rs2071425, p=0.02). On the other hand, among three novel and one known SNPs identified in the promoter region of CCL20, g. -1,706 G>A (p=0.000000055), g. -1,458 G>A (p=0.0048), and g. -962C>A (p=0.0006) were found to be significantly associated with the susceptibility of Uc. Conclusion: Altered gene expression in mononuclear cells may contribute to IBD pathogenesis. Although the findings need to be confirmed in other populations with larger numbers of patients, the current results demonstrated that polymorphisms in the promoter region of CCL20 are positively associated with the development of Uc.

• Journal of Korean Academic Society of Home Health Care Nursing
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• v.8 no.2
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• pp.109-120
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• 2001

This study has been done in order to help the people understand the cancer patients and provide the basic materials for the care of cancer patients by deeply understanding the living experience of the practice of alternative therapy for cancer patients. Data were collected with several in depth interviews and observations. Collected datas were analyzed by using phenomenological method of study by Giorgi (1970). The trial experience of alternative therapy for cancer patients has been classified into the one of having concerns, following, being infatuated, and coming out by pushing, and the experience of having concerns appeared as the meaning of the limit of modern medicine, despair, loneliness. hope, emotional support. dissolution of the feeling of uneasiness. the feeling of burden of the medical expense, self-treating, the subject of treatment. and indifference while the experience of following appeared as the meaning of blind following, temptation, going outside to look for something, wandering. following unconditionally, advise of the professionals, mistaken belief. self-abandonment, powerlessness. disconnection of dialogue with the medical staff. elevation of immunity, strengthening the physical power, absence of the source of examined information, clinging, self-responsibility. the experience of being infatuated appeared as the meaning of thorough trial. affirmative experience. devotion. diverse efforts, faithful trial. affirmative self-suggestion. change of the style of life. the feeling of burden of expense, being envious, bitter feeling toward the family, considering family, family discords, and difficulty of enforcement. The experience of coming out by pushing appeared as the meaning of waiting. self-reflection. maintaining the distance. cutting attachment, throwing the greed away, coming out by pushing. being thoughtful. accepting disease. individual difference of physical quality, and ambivalence. But they return to the experience of being concerned all over again in case of recurrence or metastasis of the disease even though they come out of such stage, and they always have ambivalence even in the condition with no recurrence and metastasis. In conclusion, the trial of alternative therapy for cancer patients could be explained as the adaptive behavior to the disease which is difficult to be cured. the cancer. The cancer patients are exposed to the side effects and harm without the examined information resources. Therefore the nurse should well aware of the alternative therapy and be able to do the appropriative management through the open communication with the patients who are under the trial of alternative therapy.

• Journal of fish pathology
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• v.27 no.1
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• pp.1-9
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• 2014

The olive flounder, Paralichthys olivaceus is susceptible to viral hemorrhagic septicaemia virus (VHSV) at $15^{\circ}C$ but no mortality at $20^{\circ}C$ even though the virus can grow well in vitro at $20^{\circ}C$. Thus, we designed an experiment to know immune response of olive flounder against VHSV when the host reared at $15^{\circ}C$ or $20^{\circ}C$. cDNA microarray analysis was performed to compare the gene expression patterns of the kidney cells between the host reared at $15^{\circ}C$ or $20^{\circ}C$. The expression of MHC class I, IL-8, myeloperoxidae and endonuclease G-like having function for the antigen presentation and chemokine-factor were up-regulted both the $15^{\circ}C$ and $20^{\circ}C$ during VHSV infection. MHC class II gene existing on antigen-presenting cells and B cell lymphocytes, immunoglobulin (Ig) genes and phagocytosis related genes were down-regulated at $15^{\circ}C$ but highly expressed at $20^{\circ}C$. It can be thought that innate immune related antigen presentation by MHC class I and phagocytosis reaction against VHSV are efficiently occur both the temperature but macrophage or B cell related antigen presentation via MHC class II fails to induce downstream immune reactions (adaptive immunity) to make antibody, and it can be one of the reason that causes high mortality only at $15^{\circ}C$.

• Proceedings of the Microbiological Society of Korea Conference
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• 2008.05a
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• pp.23-25
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• 2008

Serum complement proteins comprise an important system that is responsible for several innate and adaptive immune defence mechanisms. There were three well described pathways known to lead to the generation of a C3 convertase, which catalyses the proteolysis of complement component C3, and leads to the formation of C3 opsonins (C3b, iC3b and C3d) that fix to bacteria. A pivotal step in the complement pathway is the assembly of a C3 convertase, which digests the C3 complement component to form microbial-binding C3 fragments recognized by leukocytes. The spleen clears microorganisms from the blood. Individuals lacking this organ are more susceptible to Streptococcus pneumoniae. Innate resistance to S. pneumoniae has previously been shown to involve complement components C3 and C4, however this resistance has only a partial requirement for mediators of these three pathways, such as immunoglobulin, factor B and mannose-binding lectin. Therefore it was likely that spleen and complement system provide resistance against blood-borne S. pneumoniae infection through unknown mechanism. To better understand the mechanisms involved, we studied Specific intracellular adhesion molecule-grabbing nonintegrin (SIGN)-R1. SIGN-R1, is a C-type lectin that is expressed at high levels by spleen marginal-zone macrophages and lymph-node macrophages. SIGN-R1 has previously been shown to be the main receptor for bacterial dextrans, as well as for the capsular pneumococcal polysaccharide (CPS) of S. pneumoniae. We examined the specific role of this receptor in the activation of complement. Using a monoclonal antibody that selectively downregulates SIGN-R1 expression in vivo, we show that in response to S. pneumoniae or CPS, SIGN-R1 mediates the immediate proteolysis of C3 and fixation of C3 opsonins to S. pneumoniae or to marginal-zone macrophages that had taken up CPS. These data indicate that SIGN-R1 is largely responsible for the rapid C3 convertase formation induced by S. pneumoniae in the spleen of mice. Also, we found that SIGN-R1 directly binds C1q and that C3 fixation by SIGN-R1 requires C1q and C4 but not factor B or immunoglobulin. Traditionally C3 convertase can be formed by the classical C1q- and immunoglobulin-dependent pathway, the alternative factor-B-dependent pathway and the soluble mannose-binding lectin pathway. Furthermore Conditional SIGN-R1 knockout mice developed deficits in C3 catabolism when given S. pneumoniae or its capsular polysaccharide intravenously. There were marked reductions in proteolysis of serum C3, deposition of C3 on organisms within SIGN-$R1^+$ spleen macrophages, and formation of C3 ligands. The transmembrane lectin SIGN-R1 therefore contributes to innate resistance by an unusual C3 activation pathway. We propose that in the SIGN-R1 mediated complement activation pathway, after binding to polysaccharide, SIGN-R1 captures C1q. SIGN-R1 can then, in association with several other complement proteins including C4, lead to the formation of a C3 convertase and fixation of C3. Therefore, this new pathway for C3 fixation by SIGN-R1, which is unusual as it is a classical C1q-dependent pathway that does not require immuno globulin, contributes to innate immune resistance to certain encapsulated microorganisms.