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1.
Br J Cancer ; 130(12): 1979-1989, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38643339

ABSTRACT

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy with a poor survival rate, largely due to the lack of early diagnosis. Although myeloid cells are crucial in the tumour microenvironment, whether their specific subset can be a biomarker of PDAC progression is unclear. METHODS: We analysed IL-22 receptor expression in PDAC and peripheral blood. Additionally, we analysed gene expression profiles of IL-10R2+/IL-22R1+ myeloid cells and the presence of these cells using single-cell RNA sequencing and murine orthotropic PDAC models, respectively, followed by examining the immunosuppressive function of IL-10R2+/IL-22R1+ myeloid cells. Finally, the correlation between IL-10R2 expression and PDAC progression was evaluated. RESULTS: IL-10R2+/IL-22R1+ myeloid cells were present in PDAC and peripheral blood. Blood IL-10R2+ myeloid cells displayed a gene expression signature associated with tumour-educated circulating monocytes. IL-10R2+/IL-22R1+ myeloid cells from human myeloid cell culture inhibited T cell proliferation. By mouse models for PDAC, we found a positive correlation between pancreatic tumour growth and increased blood IL-10R2+/IL-22R1+ myeloid cells. IL-10R2+/IL-22R1+ myeloid cells from an early phase of the PDAC model suppressed T cell proliferation and cytotoxicity. IL-10R2+ myeloid cells indicated tumour recurrence 130 days sooner than CA19-9 in post-pancreatectomy patients. CONCLUSIONS: IL-10R2+/IL-22R1+ myeloid cells in the peripheral blood might be an early marker of PDAC prognosis.


Subject(s)
Biomarkers, Tumor , Carcinoma, Pancreatic Ductal , Interleukin-10 Receptor beta Subunit , Myeloid Cells , Neoplasm Recurrence, Local , Pancreatic Neoplasms , Receptors, Interleukin , Carcinoma, Pancreatic Ductal/genetics , Carcinoma, Pancreatic Ductal/pathology , Carcinoma, Pancreatic Ductal/diagnosis , Carcinoma, Pancreatic Ductal/blood , Humans , Animals , Pancreatic Neoplasms/pathology , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/diagnosis , Pancreatic Neoplasms/blood , Mice , Biomarkers, Tumor/genetics , Biomarkers, Tumor/blood , Receptors, Interleukin/genetics , Myeloid Cells/metabolism , Myeloid Cells/pathology , Neoplasm Recurrence, Local/genetics , Neoplasm Recurrence, Local/pathology , Interleukin-10 Receptor beta Subunit/genetics , Female , Male , Tumor Microenvironment/genetics , Cell Line, Tumor
2.
BMC Med ; 22(1): 122, 2024 Mar 14.
Article in English | MEDLINE | ID: mdl-38486246

ABSTRACT

BACKGROUND: Patients with fibro-calcific aortic valve disease (FCAVD) have lipid depositions in their aortic valve that engender a proinflammatory impetus toward fibrosis and calcification and ultimately valve leaflet stenosis. Although the lipoprotein(a)-autotaxin (ATX)-lysophosphatidic acid axis has been suggested as a potential therapeutic target to prevent the development of FCAVD, supportive evidence using ATX inhibitors is lacking. We here evaluated the therapeutic potency of an ATX inhibitor to attenuate valvular calcification in the FCAVD animal models. METHODS: ATX level and activity in healthy participants and patients with FCAVD were analyzed using a bioinformatics approach using the Gene Expression Omnibus datasets, enzyme-linked immunosorbent assay (ELISA), immunohistochemistry, and western blotting. To evaluate the efficacy of ATX inhibitor, interleukin-1 receptor antagonist-deficient (Il1rn-/-) mice and cholesterol-enriched diet-induced rabbits were used as the FCAVD models, and primary human valvular interstitial cells (VICs) from patients with calcification were employed. RESULTS: The global gene expression profiles of the aortic valve tissue of patients with severe FCAVD demonstrated that ATX gene expression was significantly upregulated and correlated with lipid retention (r = 0.96) or fibro-calcific remodeling-related genes (r = 0.77) in comparison to age-matched non-FCAVD controls. Orally available ATX inhibitor, BBT-877, markedly ameliorated the osteogenic differentiation and further mineralization of primary human VICs in vitro. Additionally, ATX inhibition significantly attenuated fibrosis-related factors' production, with a detectable reduction of osteogenesis-related factors, in human VICs. Mechanistically, ATX inhibitor prohibited fibrotic changes in human VICs via both canonical and non-canonical TGF-ß signaling, and subsequent induction of CTGF, a key factor in tissue fibrosis. In the in vivo FCAVD model system, ATX inhibitor exposure markedly reduced calcific lesion formation in interleukin-1 receptor antagonist-deficient mice (Il1rn-/-, P = 0.0210). This inhibition ameliorated the rate of change in the aortic valve area (P = 0.0287) and mean pressure gradient (P = 0.0249) in the FCAVD rabbit model. Moreover, transaortic maximal velocity (Vmax) was diminished with ATX inhibitor administration (mean Vmax = 1.082) compared to vehicle control (mean Vmax = 1.508, P = 0.0221). Importantly, ATX inhibitor administration suppressed the effects of a high-cholesterol diet and vitamin D2-driven fibrosis, in association with a reduction in macrophage infiltration and calcific deposition, in the aortic valves of this rabbit model. CONCLUSIONS: ATX inhibition attenuates the development of FCAVD while protecting against fibrosis and calcification in VICs, suggesting the potential of using ATX inhibitors to treat FCAVD.


Subject(s)
Aortic Valve Stenosis , Aortic Valve/pathology , Calcinosis , Humans , Animals , Mice , Rabbits , Aortic Valve Stenosis/drug therapy , Osteogenesis , Calcinosis/drug therapy , Cells, Cultured , Fibrosis , Cholesterol , Receptors, Interleukin-1 , Lipids
3.
Cell Commun Signal ; 21(1): 213, 2023 08 18.
Article in English | MEDLINE | ID: mdl-37596575

ABSTRACT

BACKGROUND: Toll-like receptor 4 (TLR4) conducts a highly regulated inflammatory process by limiting the extent of inflammation to avoid toxicity and tissue damage, even in bone tissues. Thus, it is plausible that strategies for the maintenance of normal bone-immunity to prevent undesirable bone damage by TLR4 activation can exist, but direct evidence is still lacking. METHODS: Osteoclast precursors (OCPs) obtained from WT or Slit3-deficient mice were differentiated into osteoclast (OC) with macrophage colony-stimulating factor (M-CSF), RANK ligand (RANKL) and lipopolysaccharide (LPS) by determining the number of TRAP-positive multinuclear cells (TRAP+ MNCs). To determine the alteration of OCPs population, fluorescence-activated cell sorting (FACS) was conducted in bone marrow cells in mice after LPS injection. The severity of bone loss in LPS injected WT or Slit3-deficient mice was evaluated by micro-CT analysis. RESULT: We demonstrate that TLR4 activation by LPS inhibits OC commitment by inducing the concomitant expression of miR-218-2-3p and its host gene, Slit3, in mouse OCPs. TLR4 activation by LPS induced SLIT3 and its receptor ROBO1 in BMMs, and this SLIT3-ROBO1 axis hinders RANKL-induced OC differentiation by switching the protein levels of C/EBP-ß isoforms. A deficiency of SLIT3 resulted in increased RANKL-induced OC differentiation, and the elevated expression of OC marker genes including Pu.1, Nfatc1, and Ctsk. Notably, Slit3-deficient mice showed expanded OCP populations in the bone marrow. We also found that miR-218-2 was concomitantly induced with SLIT3 expression after LPS treatment, and that this miRNA directly suppressed Tnfrsf11a (RANK) expression at both gene and protein levels, linking it to a decrease in OC differentiation. An endogenous miR-218-2 block rescued the expression of RANK and subsequent OC formation in LPS-stimulated OCPs. Aligned with these results, SLIT3-deficient mice displayed increased OC formation and reduced bone density after LPS challenge. CONCLUSION: Our findings suggest that the TLR4-dependent concomitant induction of Slit3 and miR-218-2 targets RANK in OCPs to restrain OC commitment, thereby avoiding an uncoordinated loss of bone through inflammatory processes. These observations provide a mechanistic explanation for the role of TLR4 in controlling the commitment phase of OC differentiation. Video Abstract.


Subject(s)
Osteoclasts , Toll-Like Receptor 4 , Animals , Mice , CCAAT-Enhancer-Binding Protein-beta , Lipopolysaccharides/pharmacology , Macrophages , Membrane Proteins/genetics , Nerve Tissue Proteins/genetics , Receptors, Immunologic/genetics
4.
Int Immunol ; 33(12): 723-729, 2021 11 25.
Article in English | MEDLINE | ID: mdl-34611705

ABSTRACT

The interleukin-17 (IL-17) family consists of six family members (IL-17A-IL-17F) and all the corresponding receptors have been identified recently. This family is mainly involved in the host defense mechanisms against bacteria, fungi and helminth infection by inducing cytokines and chemokines, recruiting neutrophils, inducing anti-microbial proteins and modifying T-helper cell differentiation. IL-17A and some other family cytokines are also involved in the development of psoriasis, psoriatic arthritis and ankylosing spondylitis by inducing inflammatory cytokines and chemokines, and antibodies against IL-17A as well as the receptor IL-17RA are being successfully used for the treatment of these diseases. Involvement in the development of inflammatory bowel disease, multiple sclerosis, rheumatoid arthritis and tumors has also been suggested in animal disease models. In this review, we will briefly review the mechanisms by which IL-17 cytokines are involved in the development of these diseases and discuss possible treatment of inflammatory diseases by targeting IL-17 family members.


Subject(s)
Arthritis, Rheumatoid/immunology , Inflammatory Bowel Diseases/immunology , Interleukin-17/immunology , Multiple Sclerosis/immunology , Neoplasms/immunology , Animals , Humans
5.
Int J Mol Sci ; 22(9)2021 Apr 30.
Article in English | MEDLINE | ID: mdl-33946381

ABSTRACT

Understanding the host anti-fungal immunity induced by beta-glucan has been one of the most challenging conundrums in the field of biomedical research. During the last couple of decades, insights on the role of beta-glucan in fungal disease progression, susceptibility, and resistance have been greatly augmented through the utility of various beta-glucan cognate receptor-deficient mouse models. Analysis of dectin-1 knockout mice has clarified the downstream signaling pathways and adaptive effector responses triggered by beta-glucan in anti-fungal immunity. On the other hand, assessment of CR3-deficient mice has elucidated the compelling action of beta-glucans in neutrophil-mediated fungal clearance, and the investigation of EphA2-deficient mice has highlighted its novel involvement in host sensing and defense to oral mucosal fungal infection. Based on these accounts, this review focuses on the recent discoveries made by these gene-targeted mice in beta-glucan research with particular emphasis on the multifaceted aspects of fungal immunity.


Subject(s)
Fungi/immunology , Mycoses/immunology , beta-Glucans/immunology , Adaptive Immunity , Animals , Disease Models, Animal , Gene Deletion , Humans , Immunity , Lectins, C-Type/genetics , Lectins, C-Type/immunology , Macrophage-1 Antigen/genetics , Macrophage-1 Antigen/immunology , Mice , Mice, Knockout , Mycoses/genetics , Mycoses/microbiology , Receptor, EphA2/genetics , Receptor, EphA2/immunology
6.
J Immunol ; 201(1): 167-182, 2018 07 01.
Article in English | MEDLINE | ID: mdl-29794016

ABSTRACT

IL-36α (gene symbol Il1f6), a member of the IL-36 family, is closely associated with inflammatory diseases, including colitis and psoriasis. In this study, we found that Il1f6-/- mice developed milder psoriasiform dermatitis upon treatment with imiquimod, a ligand for TLR ligand 7 (TLR7) and TLR8, whereas Il1f6-/- mice showed similar susceptibility to dextran sodium sulfate-induced colitis to wild-type mice. These effects were observed in both cohoused and separately housed conditions, and antibiotic treatment did not cancel the resistance of Il1f6-/- mice to imiquimod-induced dermatitis. Bone marrow (BM) cell transfer revealed that IL-36α expression in skin-resident cells is important for the pathogenesis of dermatitis in these mice. Following stimulation with IL-36α, the expression of Il1f6 and Il1f9 (IL-36γ), but not Il1f8 (IL-36ß), was enhanced in murine BM-derived Langerhans cells (BMLCs) and murine primary keratinocytes but not in fibroblasts from mice. Upon stimulation with agonistic ligands of TLRs and C-type lectin receptors (CLRs), Il1f6 expression was induced in BMLCs and BM-derived dendritic cells. Furthermore, IL-36α stimulation resulted in significantly increased gene expression of psoriasis-associated Th17-related cytokines and chemokines such as IL-1α, IL-1ß, IL-23, CXCL1, and CXCL2 in BMLCs and fibroblasts, and IL-1α, IL-1ß, IL-17C, and CXCL2 in keratinocytes. Collectively, these results suggest that TLR/CLR signaling-induced IL-36α plays an important role for the development of psoriasiform dermatitis by enhancing Th17-related cytokine/chemokine production in skin-resident cells via a local autoamplification loop.


Subject(s)
Adjuvants, Immunologic/toxicity , Chemokines/biosynthesis , Colitis/pathology , Imiquimod/toxicity , Interleukin-1/metabolism , Keratinocytes/metabolism , Psoriasis/pathology , Skin/pathology , Th17 Cells/immunology , Animals , Bone Marrow Cells/cytology , Bone Marrow Transplantation , Cells, Cultured , Colitis/chemically induced , Dendritic Cells/metabolism , Dextran Sulfate/toxicity , Fibroblasts/metabolism , Interleukin-1/genetics , Langerhans Cells/metabolism , Membrane Glycoproteins/metabolism , Mice , Mice, Inbred C57BL , Mice, Knockout , Psoriasis/drug therapy , Psoriasis/genetics , Skin/cytology , Toll-Like Receptor 7/metabolism , Toll-Like Receptor 8/metabolism
8.
Immunity ; 32(5): 681-91, 2010 May 28.
Article in English | MEDLINE | ID: mdl-20493731

ABSTRACT

Dectin-2 (gene symbol Clec4n) is a C-type lectin expressed by dendritic cells (DCs) and macrophages. However, its functional roles and signaling mechanisms remain to be elucidated. Here, we generated Clec4n(-/-) mice and showed that this molecule is important for host defense against Candida albicans (C. albicans). Clec4n(-/-) DCs had virtually no fungal alpha-mannan-induced cytokine production. Dectin-2 signaling induced cytokines through an FcRgamma chain and Syk-CARD9-NF-kappaB-dependent signaling pathway without involvement of MAP kinases. The yeast form of C. albicans induced interleukin-1beta (IL-1beta) and IL-23 secretion in a Dectin-2-dependent manner. In contrast, cytokine production induced by the hyphal form was only partially dependent on this lectin. Both yeast and hyphae induced Th17 cell differentiation, in which Dectin-2, but not Dectin-1, was mainly involved. Because IL-17A-deficient mice were highly susceptible to systemic candida infection, this study suggests that Dectin-2 is important in host defense against C. albicans by inducing Th17 cell differentiation.


Subject(s)
Candida albicans/immunology , Candidiasis/immunology , Cell Differentiation , Interleukin-17/metabolism , Lectins, C-Type/immunology , Mannans/immunology , T-Lymphocytes, Helper-Inducer , Animals , Cells, Cultured , Immunoassay , Interleukin-1beta/immunology , Interleukin-23/immunology , Lectins, C-Type/genetics , Male , Mice , Mice, Knockout , Signal Transduction , T-Lymphocytes, Helper-Inducer/cytology , T-Lymphocytes, Helper-Inducer/immunology
9.
Crit Rev Food Sci Nutr ; 58(3): 405-419, 2018 Feb 11.
Article in English | MEDLINE | ID: mdl-27245816

ABSTRACT

Nowadays, viruses of foodborne origin such as norovirus and hepatitis A are considered major causes of foodborne gastrointestinal illness with widespread distribution worldwide. A number of foodborne outbreaks associated with food products of animal and non-animal origins, which often involve multiple cases of variety of food streams, have been reported. Although several viruses, including rotavirus, adenovirus, astrovirus, parvovirus, and other enteroviruses, significantly contribute to incidence of gastrointestinal diseases, systematic information on the role of food in transmitting such viruses is limited. Most of the outbreak cases caused by infected food handlers were the source of 53% of total outbreaks. Therefore, prevention and hygiene measures to reduce the frequency of foodborne virus outbreaks should focus on food workers and production site of food products. Pivotal strategies, such as proper investigation, surveillance, and reports on foodborne viral illnesses, are needed in order to develop more accurate measures to detect the presence and pathogenesis of viral infection with detailed descriptions. Moreover, molecular epidemiology and surveillance of food samples may help analysis of public health hazards associated with exposure to foodborne viruses. In this present review, we discuss different aspects of foodborne viral contamination and its impact on human health. This review also aims to improve understanding of foodborne viral infections as major causes of human illness as well as provide descriptions of their control and prevention strategies and rapid detection by advanced molecular techniques. Further, a brief description of methods available for the detection of viruses in food and related matrices is provided.


Subject(s)
Food Microbiology , Foodborne Diseases/prevention & control , Animals , Disease Outbreaks/prevention & control , Food Handling/methods , Foodborne Diseases/epidemiology , Foodborne Diseases/virology , Humans , Prevalence
10.
J Immunol ; 194(12): 5681-91, 2015 Jun 15.
Article in English | MEDLINE | ID: mdl-25926676

ABSTRACT

Dendritic cell immunoreceptor (DCIR) is a C-type lectin receptor mainly expressed in DCs. Dcir (-/-) mice spontaneously develop autoimmune enthesitis and ankylosis accompanied by fibrocartilage proliferation and ectopic ossification. However, the mechanisms of new bone/cartilage formation in Dcir (-/-) mice remain to be elucidated. In this study, we show that DCIR maintains bone homeostasis by regulating IFN-γ production under pathophysiological conditions. DCIR deficiency increased bone volume in femurs and caused aberrant ossification in joints, whereas these symptoms were abolished in Rag2(-/-)Dcir(-/-) mice. IFN-γ-producing T cells accumulated in lymph nodes and joints of Dcir(-/-) mice, and purified Dcir(-/-) DCs enhanced IFN-γ(+) T cell differentiation. The ankylotic changes and bone volume increase were suppressed in the absence of IFN-γ. Thus, IFN-γ is a positive chondrogenic and osteoblastogenic factor, and DCIR is a crucial regulator of bone metabolism; consequently, both factors are potential targets for therapies directed against bone metabolic diseases.


Subject(s)
Bone and Bones/metabolism , Homeostasis/genetics , Homeostasis/immunology , Interferon-gamma/biosynthesis , Lectins, C-Type/genetics , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/metabolism , Age Factors , Animals , Ankylosis/diagnostic imaging , Ankylosis/genetics , Ankylosis/immunology , Ankylosis/pathology , Bone Density/genetics , Bone and Bones/diagnostic imaging , Bone and Bones/pathology , Cell Differentiation/genetics , Cell Differentiation/immunology , Chondrocytes/cytology , Chondrocytes/metabolism , DNA-Binding Proteins/deficiency , Dendritic Cells/immunology , Dendritic Cells/metabolism , Male , Mice , Mice, Knockout , Osteoblasts/cytology , Osteoblasts/metabolism , T-Lymphocyte Subsets/cytology , X-Ray Microtomography
11.
Food Microbiol ; 46: 307-313, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25475300

ABSTRACT

We investigated the survival and growth patterns of Aspergillus flavus and Fusarium graminearum, as well as mycotoxin production, on Korean rice as affected by the degree of milling (rough, brown, and white rice) and storage conditions (21 °C/85% relative humidity [RH], 21 °C/97% RH, and 30 °C/85% RH). When rice was stored at 21 °C/85% RH, the population of A. flavus remained constant and aflatoxin was not produced, regardless of the degree of milling. At 21 °C/97% RH and 30 °C/85% RH, the populations of A. flavus increased significantly (P ≤ 0.05) and aflatoxins were produced. The highest population of A. flavus and highest amount of aflatoxin B1 were observed on brown rice stored at 21 °C/97% RH. For F. graminearum, when stored at 85% RH, the populations were reduced to less than a detectable level (5 CFU/g of rice) within 120 days and no deoxynivalenol (DON) was produced, regardless of the degree of milling and storage temperature. However, at 21 °C/97% RH, the population of F. graminearum increased significantly (P ≤ 0.05) and DON was produced on all types of rice. Findings from this study provide insights concerning storage conditions necessary to prevent growth and mycotoxin production by A. flavus and F. graminearum on Korean rice with different degrees of milling.


Subject(s)
Aspergillus flavus/growth & development , Food Contamination/analysis , Food Storage/methods , Fusarium/growth & development , Oryza/microbiology , Spores, Fungal/growth & development , Aflatoxins/analysis , Aflatoxins/biosynthesis , Aspergillus flavus/metabolism , Food Handling , Fusarium/metabolism , Humidity , Oryza/chemistry , Oryza/classification , Particle Size , Temperature
12.
Front Immunol ; 14: 1159058, 2023.
Article in English | MEDLINE | ID: mdl-37266426

ABSTRACT

Dendritic cell immunoreceptor (DCIR) is an inhibitory C-type lectin receptor that acts as a negative regulator in the immune system and bone metabolism. We previously revealed that DCIR deficiency enhanced osteoclastogenesis and antigen presentation of dendritic cells, and that asialo-biantennary N-glycan (NA2) functions as a ligand for DCIR. NA2 binding to DCIR suppressed murine and human osteoclastogenesis that occurs in the presence of M-CSF and RANKL. The DCIR-NA2 axis, therefore, plays an important role in regulating osteoclastogenesis in both mice and humans, although the underlying mechanisms remain unclear. Here we found that Dcir -/- bone marrow-derived macrophages (BMMs) exhibited greater proliferative and differentiation responses to M-CSF and RANKL, respectively, than wild-type (WT) BMMs. Moreover, Dcir -/- osteoclasts (OCs) increased resorptive activity and cell fusion more significantly than WT OCs. DCIR deficiency affects gene expression patterns in OCs, and we found that the expression of neuraminidase 4 was increased in Dcir -/- OCs. Furthermore, DCIR-NA2 interaction in WT BMMs, but not Dcir -/- BMMs, decreased Akt phosphorylation in response to M-CSF and RANKL. These data suggest that DCIR regulates osteoclastogenesis by downregulating M-CSF and RANKL signaling, and that DCIR-mediated signaling may contribute to the terminal modification of oligosaccharides by controlling the expression of glycosylation enzymes.


Subject(s)
Bone Resorption , Macrophage Colony-Stimulating Factor , Animals , Humans , Mice , Bone Resorption/metabolism , Cell Proliferation , Macrophage Colony-Stimulating Factor/pharmacology , Macrophage Colony-Stimulating Factor/metabolism , Osteoclasts/metabolism , Signal Transduction
13.
Exp Anim ; 71(3): 288-304, 2022 Aug 05.
Article in English | MEDLINE | ID: mdl-35135958

ABSTRACT

Clec1A, a member of C-type lectin receptor family, has a carbohydrate recognition domain in its extracellular region, but no known signaling motif in the cytoplasmic domain. Clec1a is highly expressed in endothelial cells and weakly in dendritic cells. Although this molecule was reported to play an important role in the host defense against Aspergillus fumigatus by recognizing 1,8-dihydroxynaphthalene-melanin on the fungal surface, the roles of this molecule in un-infected animals remain to be elucidated. In this study, we found that Clec1a-/- mice develop milder symptoms upon induction of experimental autoimmune encephalomyelitis (EAE), an animal model for multiple sclerosis. The maximum disease score was significantly lower, and demyelination and inflammation of the spinal cord were much milder in Clec1a-/- mice compared to wild-type mice. No abnormality was detected in the immune cell composition in the draining lymph nodes and spleen on day 10 and 16 after EAE induction. Recall memory T cell proliferation after restimulation with myelin oligodendrocyte glycoprotein peptide (MOG35-55) in vitro was decreased in Clec1a-/- mice, and antigen presenting ability of Clec1a-/- dendritic cells was impaired. Interestingly, RNA-Seq and RT-qPCR analyses clearly showed that the expression of inflammatory cytokines including Il17a, Il6 and Il1b was greatly decreased in Clec1a-/- mice after induction of EAE, suggesting that this reduced cytokine production is responsible for the amelioration of EAE in Clec1a-/- mice. These observations suggest a novel function of Clec1A in the immune system.


Subject(s)
Antigen Presentation , Dendritic Cells , Encephalomyelitis, Autoimmune, Experimental , Interleukin-17 , Lectins, C-Type , Animals , Cytokines/metabolism , Dendritic Cells/metabolism , Encephalomyelitis, Autoimmune, Experimental/metabolism , Encephalomyelitis, Autoimmune, Experimental/pathology , Endothelial Cells/metabolism , Interleukin-17/metabolism , Lectins, C-Type/genetics , Lectins, C-Type/metabolism , Mice , Mice, Inbred C57BL
14.
Cell Rep ; 40(5): 111158, 2022 08 02.
Article in English | MEDLINE | ID: mdl-35926458

ABSTRACT

Dendritic cell immunoreceptor (DCIR; Clec4a2), a member of the C-type lectin receptor family, plays important roles in homeostasis of the immune and bone systems. However, the intestinal role of this molecule is unclear. Here, we show that dextran sodium sulfate (DSS)-induced colitis and azoxymethane-DSS-induced intestinal tumors are reduced in Clec4a2-/- mice independently of intestinal microbiota. STAT5 phosphorylation and expression of Csf2 and tight junction genes are enhanced, while Il17a and Cxcl2 are suppressed in the Clec4a2-/- mouse colon, which exhibits reduced infiltration of neutrophils and myeloid-derived suppressor cells. Granulocyte-macrophage colony-stimulating factor (GM-CSF) administration ameliorates DSS colitis associated with reduced Il17a and enhanced tight junction gene expression, whereas anti-GM-CSF exacerbates symptoms. Furthermore, anti-NA2, a ligand for DCIR, ameliorates colitis and prevents colorectal tumors. These observations indicate that blocking DCIR signaling ameliorates colitis and suppresses colonic tumors, suggesting DCIR as a possible target for the treatment of these diseases.


Subject(s)
Colitis , Colorectal Neoplasms , Animals , Colitis/pathology , Dextran Sulfate , Disease Models, Animal , Granulocyte-Macrophage Colony-Stimulating Factor/metabolism , Lectins, C-Type/genetics , Lectins, C-Type/metabolism , Mice , Mice, Inbred C57BL , Mice, Knockout , STAT5 Transcription Factor/metabolism
15.
Biotechnol Lett ; 33(5): 957-60, 2011 May.
Article in English | MEDLINE | ID: mdl-21246252

ABSTRACT

A simple and reliable method based on thermogravimetric analysis has been developed for determining triacylglycerol content in Chlorella sp. KR-1. There are two decomposing steps during pyrolysis of the microalgal cells and the second step of weight loss may be attributed to degradation and volatilization of triacylglycerols. The second peak height in the temperature derivatives of weight loss increased with the triacylglycerol content of the microalgal cells and the peak was around 390 °C regardless of the triacylglycerol contents. Based on these findings, a linear equation for determining triacylglycerol content was derived. The proposed method gives satisfactory results, showing small variance and a good interpolation capability.


Subject(s)
Chlorella/chemistry , Thermogravimetry/methods , Triglycerides/analysis
16.
Food Microbiol ; 28(7): 1402-8, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21839392

ABSTRACT

Aflatoxins are toxic secondary metabolites produced commonly by Aspergillus flavus and Aspergillus parasiticus. In this study, the possibility of using multiplex PCR was investigated to speed up and specify the detection of aflatoxigenic Aspergillus species in meju, a traditional Korean fermented soybean food starter. Two different sets of three primers were designed specifically for the omtB, ver-1, aflR, and omtA genes present in the aflatoxin biosynthesis cluster. The optimized multiplex PCR showed that only aflatoxigenic Aspergillus species gave three band patterns in both primer sets. The detection limits were determined as 125 pg/µl for genomic DNA from aflatoxigenic A. parasiticus KCCM 35078, and 10(5) spores/g of meju sample for DNA extracted directly from meju. A total of 65 Aspergillus isolates from meju were tested for the presence of aflatoxigenic fungi by the application of multiplex PCR, and were analyzed by TLC and HPLC for the aflatoxin production in the culture filtrates. Results showed a good correlation between the presence of the aflatoxin biosynthesis genes analyzed by multiplex PCR and aflatoxin production by TLC and HPLC. This suggests that this multiplex PCR method may provide an accurate and specific detection of aflatoxigenic Aspergillus species in fermented soybean foods.


Subject(s)
Aflatoxins/biosynthesis , Aspergillus/isolation & purification , Fermentation , Glycine max/microbiology , Multiplex Polymerase Chain Reaction/methods , Aspergillus/pathogenicity , Food Microbiology , Korea , Sensitivity and Specificity
17.
Toxins (Basel) ; 13(9)2021 09 18.
Article in English | MEDLINE | ID: mdl-34564672

ABSTRACT

Aflatoxins (AFs) are biologically active toxic metabolites, which are produced by certain toxigenic Aspergillus sp. on agricultural crops. In this study, five edible mushroom-forming fungi were analyzed using high-performance liquid chromatography fluorescence detector (HPLC-FLD) for their ability to remove aflatoxin B1 (AFB1), one of the most potent naturally occurring carcinogens known. Bjerkandera adusta and Auricularia auricular-judae showed the most significant AFB1 removal activities (96.3% and 100%, respectively) among five strains after 14-day incubation. The cell lysate from B. adusta exhibited higher AFB1 removal activity (35%) than the cell-free supernatant (13%) after 1-day incubation and the highest removal activity (80%) after 5-day incubation at 40 °C. In addition, AFB1 analyses using whole cells, cell lysates, and cell debris from B. adusta showed that cell debris had the highest AFB1 removal activity at 5th day (95%). Moreover, exopolysaccharides from B. adusta showed an increasing trend (24-48%) similar to whole cells and cell lysates after 5- day incubation. Our results strongly suggest that AFB1 removal activity by whole cells was mainly due to AFB1 binding onto cell debris during early incubation and partly due to binding onto cell lysates along with exopolysaccharides after saturation of AFB1 binding process onto cell wall components.


Subject(s)
Aflatoxin B1/metabolism , Aflatoxin B1/toxicity , Agaricales/metabolism , Aspergillus/chemistry , Aspergillus/metabolism , Biodegradation, Environmental , Food Contamination , Auricularia/metabolism , Coriolaceae/metabolism , Crops, Agricultural/microbiology , Hericium/metabolism , Republic of Korea , Shiitake Mushrooms/metabolism , Wolfiporia/metabolism
18.
J Exp Med ; 218(12)2021 12 06.
Article in English | MEDLINE | ID: mdl-34817551

ABSTRACT

Dendritic cell immunoreceptor (DCIR) is a C-type lectin receptor with a carbohydrate recognition domain and an immunoreceptor tyrosine-based inhibitory motif. Previously, we showed that Dcir-/- mice spontaneously develop autoimmune enthesitis and sialadenitis, and also develop metabolic bone abnormalities. However, the ligands for DCIR functionality remain to be elucidated. Here we showed that DCIR is expressed on osteoclasts and DCs and binds to an asialo-biantennary N-glycan(s) (NA2) on bone cells and myeloid cells. Osteoclastogenesis was enhanced in Dcir-/- cells, and NA2 inhibited osteoclastogenesis. Neuraminidase treatment, which exposes excess NA2 by removing the terminal sialic acid of N-glycans, suppressed osteoclastogenesis and DC function. Neuraminidase treatment of mice ameliorated collagen-induced arthritis and experimental autoimmune encephalomyelitis in a DCIR-dependent manner, due to suppression of antigen presentation by DCs. These results suggest that DCIR activity is regulated by the modification of the terminal sialylation of biantennary N-glycans, and this interaction is important for the control of both autoimmune and bone metabolic diseases.


Subject(s)
Dendritic Cells/physiology , Lectins, C-Type/metabolism , Membrane Glycoproteins/metabolism , Osteoclasts/metabolism , Osteogenesis/physiology , Polysaccharides/metabolism , Receptors, Immunologic/metabolism , Animals , Arthritis, Experimental/chemically induced , Arthritis, Experimental/drug therapy , Cells, Cultured , Dendritic Cells/immunology , Encephalomyelitis, Autoimmune, Experimental/drug therapy , HEK293 Cells , Humans , Lectins, C-Type/genetics , Membrane Glycoproteins/genetics , Mice, Inbred C57BL , Mice, Mutant Strains , Mice, Transgenic , N-Acetylglucosaminyltransferases/genetics , N-Acetylglucosaminyltransferases/metabolism , Neuraminidase/metabolism , Neuraminidase/pharmacology , Receptors, Immunologic/genetics
19.
Nat Commun ; 12(1): 94, 2021 01 04.
Article in English | MEDLINE | ID: mdl-33397982

ABSTRACT

TARM1 is a member of the leukocyte immunoglobulin-like receptor family and stimulates macrophages and neutrophils in vitro by associating with FcRγ. However, the function of this molecule in the regulation of the immune system is unclear. Here, we show that Tarm1 expression is elevated in the joints of rheumatoid arthritis mouse models, and the development of collagen-induced arthritis (CIA) is suppressed in Tarm1-/- mice. T cell priming against type 2 collagen is suppressed in Tarm1-/- mice and antigen-presenting ability of GM-CSF-induced dendritic cells (GM-DCs) from Tarm1-/- mouse bone marrow cells is impaired. We show that type 2 collagen is a functional ligand for TARM1 on GM-DCs and promotes DC maturation. Furthermore, soluble TARM1-Fc and TARM1-Flag inhibit DC maturation and administration of TARM1-Fc blocks the progression of CIA in mice. These results indicate that TARM1 is an important stimulating factor of dendritic cell maturation and could be a good target for the treatment of autoimmune diseases.


Subject(s)
Arthritis, Experimental/metabolism , Arthritis, Experimental/pathology , Collagen/metabolism , Dendritic Cells/pathology , Receptors, Immunologic/metabolism , Animals , Antigen Presentation , Granulocyte-Macrophage Colony-Stimulating Factor/pharmacology , Green Fluorescent Proteins/metabolism , Immunization , Ligands , Mice, Inbred C57BL , Receptors, Immunologic/deficiency
20.
J AOAC Int ; 92(2): 496-501, 2009.
Article in English | MEDLINE | ID: mdl-19485209

ABSTRACT

Following previous observations of apparent instability of fumonisin B1 in corn starch and corn meal, immunoaffinity column (IAC) cleanup, of the type used in the analysis of commercial starch-containing corn foods for fumonisins, was investigated. Foods analyzed for naturally occurring fumonisins B1, B2, and B3 included corn flour (3 different products), corn meal, and corn flakes. In 2 series of experiments, fractions were eluted by gravity or vacuum from narrow- or wide-bore Fumonitest IACs either with 2 x 2 mL methanol, followed by 2 mL methanol-water (8 + 2, v/v), or with 2 mL methanol, then 2 mL methanol-water (8 + 2, v/v). The ratio (%) of fumonisin B1 concentration in the first methanol eluate to the total concentration measured from all eluates in most cases varied from 25-70%. Incomplete recoveries were also observed for fumonisins B2 and B3. It is concluded that there can be a major underestimation of naturally occurring fumonisins in methods using only methanol elution for IAC cleanup, as in AOAC INTERNATIONAL Official Method 2001.04 (accuracy of these methods had been determined only by spiking the food with fumonisins). Elution with 2 x 2 mL methanol-water (8 + 2, v/v) was chosen as a practical procedure; means of 81-98% of the total fumonisin B1 concentration were found in the first eluate, except for corn flakes and 2 experiments with corn meal.


Subject(s)
Chromatography, Affinity/methods , Food Contamination/analysis , Fumonisins/isolation & purification , Zea mays/chemistry , Chromatography, High Pressure Liquid , Fumonisins/toxicity , Methanol , Solvents , Water , Zea mays/toxicity
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