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1.
Int J Mol Sci ; 22(19)2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34638548

RESUMO

CLEC12A is a myeloid inhibitory receptor that negatively regulates inflammation in mouse models of autoimmune and autoinflammatory arthritis. Reduced CLEC12A expression enhances myeloid cell activation and inflammation in CLEC12A knock-out mice with collagen antibody-induced or gout-like arthritis. Similarly to other C-type lectin receptors, CLEC12A harbours a stalk domain between its ligand binding and transmembrane domains. While it is presumed that the cysteines in the stalk domain have multimerisation properties, their role in CLEC12A expression and/or signaling remain unknown. We thus used site-directed mutagenesis to determine whether the stalk domain cysteines play a role in CLEC12A expression, internalisation, oligomerisation, and/or signaling. Mutation of C118 blocks CLEC12A transport through the secretory pathway diminishing its cell-surface expression. In contrast, mutating C130 does not affect CLEC12A cell-surface expression but increases its oligomerisation, inducing ligand-independent phosphorylation of the receptor. Moreover, we provide evidence that CLEC12A dimerisation is regulated in a redox-dependent manner. We also show that antibody-induced CLEC12A cross-linking induces flotillin oligomerisation in insoluble membrane domains in which CLEC12A signals. Taken together, these data indicate that the stalk cysteines in CLEC12A differentially modulate this inhibitory receptor's expression, oligomerisation and signaling, suggestive of the regulation of CLEC12A in a redox-dependent manner during inflammation.


Assuntos
Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Proteínas de Membrana/metabolismo , Células Mieloides/metabolismo , Multimerização Proteica/genética , Receptores Mitogênicos/genética , Receptores Mitogênicos/metabolismo , Linhagem Celular Tumoral , Cisteína/metabolismo , Células HEK293 , Células HeLa , Humanos , Inflamação/genética , Lectinas Tipo C/biossíntese , Proteínas de Membrana/genética , Mutagênese Sítio-Dirigida , Fosforilação , Domínios Proteicos/genética , Transporte Proteico/genética , Receptores Mitogênicos/biossíntese , Transdução de Sinais/imunologia
2.
J Am Chem Soc ; 143(42): 17465-17478, 2021 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-34652144

RESUMO

The C-type lectin receptor DC-SIGN is a pattern recognition receptor expressed on macrophages and dendritic cells. It has been identified as a promiscuous entry receptor for many pathogens, including epidemic and pandemic viruses such as SARS-CoV-2, Ebola virus, and HIV-1. In the context of the recent SARS-CoV-2 pandemic, DC-SIGN-mediated virus dissemination and stimulation of innate immune responses has been implicated as a potential factor in the development of severe COVID-19. Inhibition of virus binding to DC-SIGN, thus, represents an attractive host-directed strategy to attenuate overshooting innate immune responses and prevent the progression of the disease. In this study, we report on the discovery of a new class of potent glycomimetic DC-SIGN antagonists from a focused library of triazole-based mannose analogues. Structure-based optimization of an initial screening hit yielded a glycomimetic ligand with a more than 100-fold improved binding affinity compared to methyl α-d-mannopyranoside. Analysis of binding thermodynamics revealed an enthalpy-driven improvement of binding affinity that was enabled by hydrophobic interactions with a loop region adjacent to the binding site and displacement of a conserved water molecule. The identified ligand was employed for the synthesis of multivalent glycopolymers that were able to inhibit SARS-CoV-2 spike glycoprotein binding to DC-SIGN-expressing cells, as well as DC-SIGN-mediated trans-infection of ACE2+ cells by SARS-CoV-2 spike protein-expressing viruses, in nanomolar concentrations. The identified glycomimetic ligands reported here open promising perspectives for the development of highly potent and fully selective DC-SIGN-targeted therapeutics for a broad spectrum of viral infections.


Assuntos
Antivirais/farmacologia , COVID-19/tratamento farmacológico , Moléculas de Adesão Celular/metabolismo , Lectinas Tipo C/metabolismo , Receptores de Superfície Celular/metabolismo , COVID-19/metabolismo , COVID-19/virologia , Humanos , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/metabolismo
3.
Int J Mol Sci ; 22(19)2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34638920

RESUMO

Glycan-lectin interactions play an essential role in different cellular processes. One of their main functions is involvement in the immune response to pathogens or inflammation. However, cancer cells and viruses have adapted to avail themselves of these interactions. By displaying specific glycosylation structures, they are able to bind to lectins, thus promoting pathogenesis. While glycan-lectin interactions promote tumor progression, metastasis, and/or chemoresistance in cancer, in viral infections they are important for viral entry, release, and/or immune escape. For several years now, a growing number of investigations have been devoted to clarifying the role of glycan-lectin interactions in cancer and viral infections. Various overviews have already summarized and highlighted their findings. In this review, we consider the interactions of the lectins MGL, DC-SIGN, selectins, and galectins in both cancer and viral infections together. A possible transfer of ways to target and disrupt them might lead to new therapeutic approaches in different pathological backgrounds.


Assuntos
Lectinas/metabolismo , Neoplasias/metabolismo , Polissacarídeos/metabolismo , Viroses/metabolismo , Animais , Moléculas de Adesão Celular/química , Moléculas de Adesão Celular/metabolismo , Galectinas/química , Galectinas/metabolismo , Humanos , Lectinas/química , Lectinas Tipo C/química , Lectinas Tipo C/metabolismo , Polissacarídeos/química , Ligação Proteica , Receptores de Superfície Celular/química , Receptores de Superfície Celular/metabolismo , Selectinas/química , Selectinas/metabolismo , Viroses/virologia
4.
Nat Commun ; 12(1): 5932, 2021 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-34635656

RESUMO

Domestic ducks are raised for meat, eggs and feather down, and almost all varieties are descended from the Mallard (Anas platyrhynchos). Here, we report chromosome-level high-quality genome assemblies for meat and laying duck breeds, and the Mallard. Our new genomic databases contain annotations for thousands of new protein-coding genes and recover a major percentage of the presumed "missing genes" in birds. We obtain the entire genomic sequences for the C-type lectin (CTL) family members that regulate eggshell biomineralization. Our population and comparative genomics analyses provide more than 36 million sequence variants between duck populations. Furthermore, a mutant cell line allows confirmation of the predicted anti-adipogenic function of NR2F2 in the duck, and uncovered mutations specific to Pekin duck that potentially affect adipose deposition. Our study provides insights into avian evolution and the genetics of oviparity, and will be a rich resource for the future genetic improvement of commercial traits in the duck.


Assuntos
Adipogenia/genética , Proteínas Aviárias/genética , Fator II de Transcrição COUP/genética , Patos/genética , Genoma , Lectinas Tipo C/genética , Tecido Adiposo/citologia , Tecido Adiposo/metabolismo , Animais , Proteínas Aviárias/classificação , Proteínas Aviárias/metabolismo , Cruzamento , Fator II de Transcrição COUP/metabolismo , Domesticação , Casca de Ovo/metabolismo , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Ontologia Genética , Lectinas Tipo C/metabolismo , Metabolismo dos Lipídeos/genética , Masculino , Anotação de Sequência Molecular , Mutação , Zigoto/metabolismo
5.
Elife ; 102021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34609281

RESUMO

Brain microglia and border-associated macrophages (BAMs) display distinct spatial, developmental, and phenotypic features. Although at steady state, the origins of distinct brain macrophages are well-documented, the dynamics of their replenishment in neurodegenerative disorders remain elusive, particularly for activated CD11c+ microglia and BAMs. In this study, we conducted a comprehensive fate-mapping analysis of murine microglia and BAMs and their turnover kinetics during Alzheimer's disease (AD) progression. We used a novel inducible AD mouse model to investigate the contribution of bone marrow (BM) cells to the pool of fetal-derived brain macrophages during the development of AD. We demonstrated that microglia remain a remarkably stable embryonic-derived population even during the progression of AD pathology, indicating that neither parenchymal macrophage subpopulation originates from, nor is replenished by, BM-derived cells. At the border-associated brain regions, bona fide CD206+ BAMs are minimally replaced by BM-derived cells, and their turnover rates are not accelerated by AD. In contrast, all other myeloid cells are swiftly replenished by BM progenitors. This information further elucidates the turnover kinetics of these cells not only at steady state, but also in neurodegenerative diseases, which is crucial for identifying potential novel therapeutic targets.


Assuntos
Doença de Alzheimer/metabolismo , Lectinas Tipo C/metabolismo , Macrófagos/metabolismo , Lectinas de Ligação a Manose/metabolismo , Microglia/metabolismo , Receptores de Superfície Celular/metabolismo , Doença de Alzheimer/embriologia , Animais , Modelos Animais de Doenças , Camundongos
6.
Glycoconj J ; 38(5): 611-623, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34542788

RESUMO

The severe acute respiratory syndrome-related coronavirus-2 (SARS-CoV-2) infection displays a wide array of clinical manifestations. Although some risk factors for coronavirus disease 2019 (COVID-19) severity and outcomes have been identified the underlying biologic mechanisms are still not well understood. The surface SARS-CoV-2 proteins are heavily glycosylated enabling host cell interaction and viral entry. Angiotensin-converting enzyme 2 (ACE2) has been identified to be the main host cell receptor enabling SARS-CoV-2 cell entry after interaction with its S glycoprotein. However, recent studies report SARS-CoV-2 S glycoprotein interaction with other cell receptors, mainly C-type lectins which recognize specific glycan epitopes facilitating SARS-CoV-2 entry to susceptible cells. Here, we are summarizing the main findings on SARS-CoV-2 interactions with ACE2 and other cell membrane surface receptors and soluble lectins involved in the viral cell entry modulating its infectivity and potentially playing a role in subsequent clinical manifestations of COVID-19.


Assuntos
Enzima de Conversão de Angiotensina 2/metabolismo , COVID-19/metabolismo , Glicoproteínas/metabolismo , Lectinas Tipo C/metabolismo , SARS-CoV-2/fisiologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Internalização do Vírus , Glicosilação , Humanos
7.
Cells ; 10(9)2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34572076

RESUMO

Coronavirus disease 19 (COVID-19) is caused by an enveloped, positive-sense, single-stranded RNA virus, referred to as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which belongs to the realm Riboviria, order Nidovirales, family Coronaviridae, genus Betacoronavirus and the species Severe acute respiratory syndrome-related coronavirus. This viral disease is characterized by a myriad of varying symptoms, such as pyrexia, cough, hemoptysis, dyspnoea, diarrhea, muscle soreness, dysosmia, lymphopenia and dysgeusia amongst others. The virus mainly infects humans, various other mammals, avian species and some other companion livestock. SARS-CoV-2 cellular entry is primarily accomplished by molecular interaction between the virus's spike (S) protein and the host cell surface receptor, angiotensin-converting enzyme 2 (ACE2), although other host cell-associated receptors/factors, such as neuropilin 1 (NRP-1) and neuropilin 2 (NRP-2), C-type lectin receptors (CLRs), as well as proteases such as TMPRSS2 (transmembrane serine protease 2) and furin, might also play a crucial role in infection, tropism, pathogenesis and clinical outcome. Furthermore, several structural and non-structural proteins of the virus themselves are very critical in determining the clinical outcome following infection. Considering such critical role(s) of the abovementioned host cell receptors, associated proteases/factors and virus structural/non-structural proteins (NSPs), it may be quite prudent to therapeutically target them through a multipronged clinical regimen to combat the disease.


Assuntos
COVID-19 , Interações entre Hospedeiro e Microrganismos , SARS-CoV-2/patogenicidade , Enzima de Conversão de Angiotensina 2/química , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , COVID-19/patologia , COVID-19/virologia , Sistemas de Liberação de Medicamentos , Furina/química , Furina/metabolismo , Humanos , Lectinas Tipo C/química , Lectinas Tipo C/metabolismo , Estrutura Molecular , Neuropilinas/química , Neuropilinas/metabolismo , Peptidil Dipeptidase A/química , Peptidil Dipeptidase A/metabolismo , Ligação Proteica , Receptores Virais/química , Receptores Virais/metabolismo , Serina Endopeptidases/química , Serina Endopeptidases/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismo , Resultado do Tratamento , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/metabolismo , Internalização do Vírus
8.
Int J Mol Sci ; 22(17)2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34502134

RESUMO

The current spreading coronavirus SARS-CoV-2 is highly infectious and pathogenic. In this study, we screened the gene expression of three host receptors (ACE2, DC-SIGN and L-SIGN) of SARS coronaviruses and dendritic cells (DCs) status in bulk and single cell transcriptomic datasets of upper airway, lung or blood of COVID-19 patients and healthy controls. In COVID-19 patients, DC-SIGN gene expression was interestingly decreased in lung DCs but increased in blood DCs. Within DCs, conventional DCs (cDCs) were depleted while plasmacytoid DCs (pDCs) were augmented in the lungs of mild COVID-19. In severe cases, we identified augmented types of immature DCs (CD22+ or ANXA1+ DCs) with MHCII downregulation. In this study, our observation indicates that DCs in severe cases stimulate innate immune responses but fail to specifically present SARS-CoV-2. It provides insights into the profound modulation of DC function in severe COVID-19.


Assuntos
COVID-19/imunologia , Moléculas de Adesão Celular/genética , Células Dendríticas/imunologia , Regulação da Expressão Gênica/imunologia , Lectinas Tipo C/genética , Receptores de Superfície Celular/genética , SARS-CoV-2/imunologia , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/metabolismo , COVID-19/diagnóstico , COVID-19/patologia , COVID-19/virologia , Moléculas de Adesão Celular/metabolismo , Conjuntos de Dados como Assunto , Células Dendríticas/metabolismo , Estudo de Associação Genômica Ampla , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Humanos , Imunidade Inata , Lectinas Tipo C/metabolismo , Pulmão/imunologia , Pulmão/patologia , Pulmão/virologia , Análise da Randomização Mendeliana , Nasofaringe/imunologia , Nasofaringe/patologia , Nasofaringe/virologia , RNA-Seq , Receptores de Superfície Celular/metabolismo , Índice de Gravidade de Doença , Análise de Célula Única
9.
Sci Rep ; 11(1): 17737, 2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-34489491

RESUMO

Lactic acid bacteria (LAB) are most generally used as probiotics and some strains of LAB are known to have anti-inflammatory effects. A specific strain of lactic acid bacteria, Lactobacillus paracasei KW3110 (KW3110), activates macrophages to produce interleukin-10 (IL-10), an anti-inflammatory cytokine; however, the biological mechanism remains unclear. In this study, we showed that the amount of incorporated KW3110 into a macrophage cell line, RAW 264.7, was higher than other genetically related strains using fluorescence microscopy. RNA-seq analysis indicated that treatment of macrophages with KW3110 induced Dectin-2 gene expression, which is a pattern recognition receptor, recognizing α-mannose. In addition, antibody treatment and knock down of Dectin-2, or factors downstream in the signaling pathway, decreased the amount of incorporated KW3110 and IL-10 production. Substantial lectin array analysis also revealed that KW3110 had higher binding affinities to lectins, which recognize the carbohydrate chains comprised of α-mannose, than two other LAB. In conclusion, KW3110 is readily incorporated into macrophages, leading to IL-10 production. Dectin-2 mediated the phagocytosis of KW3110 into macrophages and this may be involved with the characteristic carbohydrate chains of KW3110.


Assuntos
Interleucina-10/metabolismo , Lactobacillus paracasei , Lectinas Tipo C/metabolismo , Macrófagos/metabolismo , Fagocitose/fisiologia , Animais , Lectinas Tipo C/genética , Macrófagos/microbiologia , Camundongos , Microscopia de Fluorescência , Células RAW 264.7
10.
J Med Chem ; 64(19): 14332-14343, 2021 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-34524803

RESUMO

In addition to a variety of viral-glycoprotein receptors (e.g., heparan sulfate, Niemann-Pick C1, etc.), dendritic cell-specific intercellular adhesion molecule-3-grabbing nonintegrin (DC-SIGN), from the C-type lectin receptor family, plays one of the most important pathogenic functions for a wide range of viruses (e.g., Ebola, human cytomegalovirus (HCMV), HIV-1, severe acute respiratory syndrome coronavirus 2, etc.) that invade host cells before replication; thus, its inhibition represents a relevant extracellular antiviral therapy. We report two novel p-tBu-calixarene glycoclusters 1 and 2, bearing tetrahydroxamic acid groups, which exhibit micromolar inhibition of soluble DC-SIGN binding and provide nanomolar IC50 inhibition of both DC-SIGN-dependent Jurkat cis-cell infection by viral particle pseudotyped with Ebola virus glycoprotein and the HCMV-gB-recombinant glycoprotein interaction with monocyte-derived dendritic cells expressing DC-SIGN. A unique cooperative involvement of sugar, linker, and calixarene core is likely behind the strong avidity of DC-SIGN for these low-valent systems. We claim herein new promising candidates for the rational development of a large spectrum of antiviral therapeutics.


Assuntos
Calixarenos/química , Moléculas de Adesão Celular/antagonistas & inibidores , Glicoconjugados/metabolismo , Glicoproteínas/antagonistas & inibidores , Ácidos Hidroxâmicos/química , Lectinas Tipo C/antagonistas & inibidores , Fenóis/química , Receptores de Superfície Celular/antagonistas & inibidores , Proteínas Virais/antagonistas & inibidores , Antivirais/química , Antivirais/metabolismo , Antivirais/farmacologia , Moléculas de Adesão Celular/metabolismo , Linhagem Celular , Citomegalovirus/metabolismo , Células Dendríticas/citologia , Células Dendríticas/metabolismo , Ebolavirus/fisiologia , Glicoconjugados/química , Glicoconjugados/farmacologia , Glicoproteínas/genética , Glicoproteínas/metabolismo , Humanos , Células Jurkat , Lectinas Tipo C/metabolismo , Modelos Biológicos , Ligação Proteica , Receptores de Superfície Celular/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Proteínas Virais/genética , Proteínas Virais/metabolismo
11.
Int J Mol Sci ; 22(16)2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34445130

RESUMO

Background: Naltrexone is an opioid receptor antagonist commonly used to treat opioid and alcohol dependence. The use of low dose naltrexone (LDN) was found to have anti-inflammatory properties for treatment of diseases such as fibromyalgia, Crohn's disease, multiple sclerosis and regional pain syndromes. Related to its anti-neuroinflammatory properties, the mechanism of action is possibly mediated via Toll-like receptor 4 antagonism, which is widely expressed on microglial cells. The aim of the present study was to assess the immunometabolic effects of naltrexone on microglia cells in in vitro conditions. METHODS: All experiments were performed in the BV-2 microglial cell line. The cells were treated with naltrexone at 100 µM concentrations corresponding to low dose for 24 h. Cell viability was assessed for every drug dose. To induce additional activation, the cells were pretreated with LPS and IFN-γ. Immunofluorescence was used to analyse the classical microglial activation markers iNOS and CD206, while Seahorse was used for real-time cellular metabolic assessments. mTOR activity measured over the expression of a major direct downstream target S6K was assessed using western blot. RESULTS: LDN induced a shift from highly activated pro-inflammatory phenotype (iNOShighCD206low) to quiescent anti-inflammatory M2 phenotype (iNOSlowCD206high) in BV-2 microglia cells. Changes in the inflammatory profile were accompanied by cellular metabolic switching based on the transition from high glycolysis to mitochondrial oxidative phosphorylation (OXPHOS). LDN-treated cells were able to maintain a metabolically suppressive phenotype by supporting OXPHOS with high oxygen consumption, and also maintain a lower energetic state due to lower lactate production. The metabolic shift induced by transition from glycolysis to mitochondrial oxidative metabolism was more prominent in cells pretreated with immunometabolic modulators such as LPS and IFN-γ. In a dose-dependent manner, naltrexone also modulated mTOR/S6K expression, which underlies the cell metabolic phenotype regulating microglia immune properties and adaptation. CONCLUSION: By modulating the phenotypic features by metabolic switching of activated microglia, naltrexone was found to be an effective and powerful tool for immunometabolic reprogramming and could be a promising novel treatment for various neuroinflammatory conditions.


Assuntos
Microglia/efeitos dos fármacos , Naltrexona/farmacologia , Antagonistas de Entorpecentes/farmacologia , Anti-Inflamatórios/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Humanos , Lectinas Tipo C/metabolismo , Lectinas de Ligação a Manose/metabolismo , Microglia/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Fosforilação Oxidativa/efeitos dos fármacos , Receptores de Superfície Celular/metabolismo , Transdução de Sinais/efeitos dos fármacos
12.
Cancer Invest ; 39(9): 777-782, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34344244

RESUMO

OBJECTIVE: Multiple myeloma is an incurable hematological malignancy. Currently, the use of proteasome inhibitors could be superior to chemotherapy-based regimen in the treatment of this disease. However, resistance to bortezomib combination therapy still occurs in some patients. So, this research work aims to assess CD69 and CD56 expression in these cases and their relation to the response to therapy. MATERIALS AND METHODS: Immunophenotyping by 4-color multi-parameter flow cytometry was carried out on 98 multiple myeloma cases. Clonal plasma cells were gated by co-expression of CD38 with CD138 with low SSC, negative or dim CD45. RESULTS: Double negative CD69 and CD56 (47.9%) multiple myeloma cases were associated with high serum ß2 microglobulin, creatinine, calcium and low serum albumin. There was also a significant correlation between the absence of these markers with osteolytic lesions and unfavorable cytogenetic t (4;14) (p < 0.001). Moreover, there was a highly significant correlation between CD69- and CD56- with non-response to bortezomib combination therapy in multiple myeloma patients (p < 0.0001). Regression analysis for the prediction of non- response to treatment in these cases using different prognostic indicators revealed that high serum ß2 microglobulin, unfavorable cytogenetic, advanced stage, and low expression of CD69 and CD56 were poor predictors of non-response. CONCLUSION: CD69 in association with CD56 could be an independent prognostic factor in multiple myeloma cases. It could be used in the routine laboratory assessment for refining stratification and timely therapeutic decision for highly cost therapy in developing countries.


Assuntos
Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Antineoplásicos/uso terapêutico , Antígeno CD56/metabolismo , Lectinas Tipo C/metabolismo , Mieloma Múltiplo/tratamento farmacológico , Idoso , Bortezomib/administração & dosagem , Feminino , Citometria de Fluxo/métodos , Humanos , Imunofenotipagem/métodos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/metabolismo , Prognóstico
13.
Biomed Res Int ; 2021: 7988320, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34337052

RESUMO

Age is a key factor in intervertebral disc (IVD) degeneration; however, the changes that occur in IVDs with age are not fully understood. Tissue-resident macrophages are critical for tissue homeostasis and are regulated by transforming growth factor- (TGF-) ß. We examined changes in the proportion of resident macrophages in young versus aged mice and the role of TGF-ß in regulating resident macrophages in IVDs. IVDs were harvested from 4-month (young) and 18-month-old (aged) C57BL/6J mice. The proportion of macrophages in IVDs was determined using flow cytometry (n = 5 for each time point) and the expression of Cd11b, Cd206, and Tgfb genes, which encode CD11b, CD206, and TGF-ß protein, respectively, using real-time PCR. To study the role of TGF-ß in the polarization of resident macrophages, resident macrophages isolated from IVDs from young and aged mice were treated with recombinant TGF-ß with and without a TGF-ß inhibitor (SB431542). Additionally, SB431542 was intraperitoneally injected into young and aged mice, and Cd206 expression was examined using real-time PCR (n = 10 for each time point). The proportion of CD11b+ and CD11b+ CD206+ cells was significantly reduced in aged versus young mice, as was Cd11b, Cd206, and Tgfb expression. TGF-ß/IL10 stimulation significantly increased the expression of Cd206, an M2 macrophage marker, in disc macrophages from both young and aged mice. Meanwhile, administration of a TGF-ß inhibitor significantly reduced Cd206 expression compared to vehicle control in both groups. Conclusion. Resident macrophages decrease with age in IVDs, which may be associated with the concomitant decrease in TGF-ß. Our findings provide new insight into the mechanisms of age-related IVD pathology.


Assuntos
Envelhecimento/metabolismo , Disco Intervertebral/metabolismo , Lectinas Tipo C/metabolismo , Macrófagos/metabolismo , Lectinas de Ligação a Manose/metabolismo , Receptores de Superfície Celular/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Animais , Biomarcadores/metabolismo , Células Cultivadas , Masculino , Camundongos Endogâmicos C57BL
14.
Biomolecules ; 11(8)2021 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-34439744

RESUMO

Galectins are one of the critical players in the tumor microenvironment-tumor crosstalk and the regulation of local immunity. Galectin-9 has been in the limelight in tumor immunology. Galectin-9 possesses its multiplex biological functions both extracellularly and intracellularly, plays a pivotal role in the modulation of adaptive and innate immunity, and induces immune tolerance. NK-92MI cell lines against different malignancies were extensively studied, and recently published trials used genetically chimeric antigen receptor-transfected NK-92MI cells in tumor immunotherapy. Besides the intensive research in tumor immunotherapy, limited information is available on their immune-checkpoint expression and the impact of checkpoint ligands on their effector functions. To uncover the therapeutic potential of modulating Galectin-9-related immunological pathways in NK-cell-based therapy, we investigated the dose-dependent effect of soluble Galectin-9 on the TIM-3 checkpoint receptor and NKG2D, CD69, FasL, and perforin expression of NK-92MI cells. We also examined how their cytotoxicity and cytokine production was altered after Gal-9 treatment and in the presence of different serum supplements using flow cytometric analysis. Our study provides evidence that the Galectin-9/TIM-3 pathway plays an important role in the regulation of NK cell function, and about the modulatory role of Galectin-9 on the cytotoxicity and cytokine production of NK-92MI cells in the presence of different serum supplements. We hope that our results will aid the development of novel NK-cell-based strategies that target Galectin-9/TIM-3 checkpoint in tumors resistant to T-cell-based immunotherapy.


Assuntos
Galectinas/metabolismo , Linfoma não Hodgkin/patologia , Soro/química , Imunidade Adaptativa , Animais , Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Linhagem Celular Tumoral , Citocinas/metabolismo , Proteína Ligante Fas/metabolismo , Expressão Gênica , Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Humanos , Imunidade Inata , Imunoterapia/métodos , Células K562 , Células Matadoras Naturais/metabolismo , Lectinas Tipo C/metabolismo , Linfoma não Hodgkin/metabolismo , Camundongos , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Neoplasias/imunologia , Neoplasias/patologia , Perforina/metabolismo , Fenótipo , Proteínas Recombinantes/química , Microambiente Tumoral
15.
Int J Mol Sci ; 22(16)2021 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-34445445

RESUMO

Ascariasis is a global health problem for humans and animals. Adult Ascaris nematodes are long-lived in the host intestine where they interact with host cells as well as members of the microbiota resulting in chronic infections. Nematode interactions with host cells and the microbial environment are prominently mediated by parasite-secreted proteins and peptides possessing immunomodulatory and antimicrobial activities. Previously, we discovered the C-type lectin protein AsCTL-42 in the secreted products of adult Ascaris worms. Here we tested recombinant AsCTL-42 for its ability to interact with bacterial and host cells. We found that AsCTL-42 lacks bactericidal activity but neutralized bacterial cells without killing them. Treatment of bacterial cells with AsCTL-42 reduced invasion of intestinal epithelial cells by Salmonella. Furthermore, AsCTL-42 interacted with host myeloid C-type lectin receptors. Thus, AsCTL-42 is a parasite protein involved in the triad relationship between Ascaris, host cells, and the microbiota.


Assuntos
Ascaris suum/metabolismo , Interações Hospedeiro-Parasita , Mucosa Intestinal/metabolismo , Lectinas Tipo C/metabolismo , Lectinas/metabolismo , Salmonella , Animais , Ascaríase/metabolismo , Ascaríase/microbiologia , Ascaris suum/microbiologia , Ascaris suum/fisiologia , Linhagem Celular , Lectinas/fisiologia , Proteínas Recombinantes , Sus scrofa/microbiologia , Sus scrofa/parasitologia
16.
Immunity ; 54(9): 2133-2142.e3, 2021 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-34453880

RESUMO

SARS-CoV-2 mRNA vaccines have shown remarkable clinical efficacy, but questions remain about the nature and kinetics of T cell priming. We performed longitudinal antigen-specific T cell analyses on healthy SARS-CoV-2-naive and recovered individuals prior to and following mRNA prime and boost vaccination. Vaccination induced rapid antigen-specific CD4+ T cell responses in naive subjects after the first dose, whereas CD8+ T cell responses developed gradually and were variable in magnitude. Vaccine-induced Th1 and Tfh cell responses following the first dose correlated with post-boost CD8+ T cells and neutralizing antibodies, respectively. Integrated analysis revealed coordinated immune responses with distinct trajectories in SARS-CoV-2-naive and recovered individuals. Last, whereas booster vaccination improved T cell responses in SARS-CoV-2-naive subjects, the second dose had little effect in SARS-CoV-2-recovered individuals. These findings highlight the role of rapidly primed CD4+ T cells in coordinating responses to the second vaccine dose in SARS-CoV-2-naive individuals.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Vacinas contra COVID-19/imunologia , COVID-19/imunologia , SARS-CoV-2/fisiologia , Células Th1/imunologia , Adulto , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Feminino , Humanos , Imunidade Celular , Imunidade Humoral , Imunização Secundária , Memória Imunológica , Lectinas Tipo C/metabolismo , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Peptídeos/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinação , Adulto Jovem
17.
Sci Rep ; 11(1): 16836, 2021 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-34413427

RESUMO

Fluid resuscitation via colon (FRVC) is a complementary therapeutic procedure for early-stage cases of severe acute pancreatitis (SAP). The expression of intestinal dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin (DC-SIGN) regulates systemic inflammation. This study aimed to investigate the effect of FRVC on the expression of DC-SIGN in the colon tissue of SAP rats and its effect on the early response of systemic inflammatory and multiple organ injury. SAP was induced in rats via retrograde injection of sodium taurocholate into the biliopancreatic duct. DC-SIGN expression of appeared in the proximal and distal colon. Histological characteristics and inflammatory cytokines were examined to compare the effect of FRVC and intravenous fluid resuscitation (IVFR). The results showed that DC-SIGN expression in the proximal colon increased in a time-dependent manner in the early-stage of SAP rats. FRVC inhibited DC-SIGN expression in the proximal colon. Both FRVC and IVFR alleviated histological injuries of the pancreas and colon. However, FRVC had an advantage over IVFR in alleviating lung injury and reducing serum TNF-α, IL-6 and LPS. These results suggest that FRVC treatment might help suppress systemic inflammation and prevent subsequent organ failure in early-stage SAP rats likely through inhibiting DC-SIGN expression in the proximal colon.


Assuntos
Colo/patologia , Hidratação , Inflamação/patologia , Inflamação/terapia , Pancreatite/patologia , Pancreatite/terapia , Animais , Moléculas de Adesão Celular/metabolismo , Citocinas/metabolismo , Lectinas Tipo C/metabolismo , Masculino , Especificidade de Órgãos , Ratos Sprague-Dawley , Receptores de Superfície Celular/metabolismo , Fatores de Tempo
18.
Front Immunol ; 12: 686846, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34408745

RESUMO

Chitooligosaccharide (COS) is an important immune enhancer and has been proven to have a variety of biological activities. Our previous research has established an M1 polarization mode by COS in blunt snout bream (Megalobrama amblycephala) macrophages, but the mechanism of COS activation of blunt snout bream macrophages remains unclear. In this study, we further explored the internalization mechanism and signal transduction pathway of chitooligosaccharide hexamer (COS6) in blunt snout bream macrophages. The results showed that mannose receptor C-type lectin-like domain 4-8 of M. amblycephala (MaMR CTLD4-8) could recognize and bind to COS6 and mediate COS6 into macrophages by both clathrin-dependent and caveolin-dependent pathways. In the inflammatory response of macrophages activated by COS6, the gene expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, and nitric oxide synthase 2 (NOS2) was significantly inhibited after MaMR CTLD4-8-specific antibody blockade. However, even if it was blocked, the expression of these inflammation-related genes was still relatively upregulated, which suggested that there are other receptors involved in immune regulation. Further studies indicated that MaMR CTLD4-8 and Toll-like receptor 4 (TLR4) cooperated to regulate the pro-inflammatory response of macrophages caused by COS6. Taken together, these results revealed that mannose receptor (MR) CTLD4-8 is indispensable in the process of recognition, binding, internalization, and immunoregulation of COS in macrophages of blunt snout bream.


Assuntos
Quitosana/metabolismo , Cyprinidae/imunologia , Expressão Gênica , Lectinas Tipo C/metabolismo , Macrófagos/imunologia , Lectinas de Ligação a Manose/metabolismo , Oligossacarídeos/metabolismo , Receptores de Superfície Celular/metabolismo , Animais , Anticorpos/efeitos adversos , Cyprinidae/metabolismo , Interleucina-1beta/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Transdução de Sinais , Linfócitos T Reguladores/imunologia , Receptores Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
19.
Nature ; 598(7880): 342-347, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34464958

RESUMO

SARS-CoV-2 infection-which involves both cell attachment and membrane fusion-relies on the angiotensin-converting enzyme 2 (ACE2) receptor, which is paradoxically found at low levels in the respiratory tract1-3, suggesting that there may be additional mechanisms facilitating infection. Here we show that C-type lectin receptors, DC-SIGN, L-SIGN and the sialic acid-binding immunoglobulin-like lectin 1 (SIGLEC1) function as attachment receptors by enhancing ACE2-mediated infection and modulating the neutralizing activity of different classes of spike-specific antibodies. Antibodies to the amino-terminal domain or to the conserved site at the base of the receptor-binding domain, while poorly neutralizing infection of ACE2-overexpressing cells, effectively block lectin-facilitated infection. Conversely, antibodies to the receptor binding motif, while potently neutralizing infection of ACE2-overexpressing cells, poorly neutralize infection of cells expressing DC-SIGN or L-SIGN and trigger fusogenic rearrangement of the spike, promoting cell-to-cell fusion. Collectively, these findings identify a lectin-dependent pathway that enhances ACE2-dependent infection by SARS-CoV-2 and reveal distinct mechanisms of neutralization by different classes of spike-specific antibodies.


Assuntos
Anticorpos Neutralizantes/imunologia , Lectinas/metabolismo , SARS-CoV-2/metabolismo , SARS-CoV-2/patogenicidade , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , Moléculas de Adesão Celular/metabolismo , Fusão Celular , Linhagem Celular , Cricetinae , Feminino , Humanos , Lectinas/imunologia , Lectinas Tipo C/metabolismo , Fusão de Membrana , Receptores de Superfície Celular/metabolismo , SARS-CoV-2/imunologia , Lectina 1 Semelhante a Ig de Ligação ao Ácido Siálico/metabolismo , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismo
20.
Int J Mol Sci ; 22(13)2021 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-34281249

RESUMO

Regenerating gene (REG) family proteins serve as multifunctional secretory molecules with trophic, antiapoptotic, anti-inflammatory, antimicrobial and probably immuno-regulatory effects. Since their discovery, accumulating evidence has clarified the potential roles of the REG family in the occurrence, progression and development of a wide range of inflammatory and inflammation-associated diseases of the gastrointestinal (GI) tract. However, significant gaps still exist due to the undefined nature of certain receptors, regulatory signaling pathways and possible interactions among distinct Reg members. In this narrative review, we first describe the structural features, distribution pattern and purported regulatory mechanisms of REG family proteins. Furthermore, we summarize the established and proposed roles of REG proteins in the pathogenesis of various inflammation-associated pathologies of the GI tract and the body as a whole, focusing particularly on carcinogenesis in the ulcerative colitis-colitic cancer sequence and gastric cancer. Finally, the clinical relevance of REG products in the context of diagnosis, treatment and prognostication are also discussed in detail. The current evidence suggests a need to better understanding the versatile roles of Reg family proteins in the pathogenesis of inflammatory-associated diseases, and their broadened future usage as therapeutic targets and prognostic biomarkers is anticipated.


Assuntos
Gastroenteropatias/metabolismo , Trato Gastrointestinal/metabolismo , Inflamação/imunologia , Animais , Apoptose/genética , Gastroenteropatias/imunologia , Trato Gastrointestinal/imunologia , Humanos , Inflamação/metabolismo , Doenças Inflamatórias Intestinais , Mucosa Intestinal/metabolismo , Lectinas Tipo C/metabolismo , Litostatina/genética , Litostatina/metabolismo , Proteínas Associadas a Pancreatite/genética , Proteínas Associadas a Pancreatite/metabolismo , Neoplasias Gástricas
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